The Disclaimers, Legal Stuff and Butt-Covering Section: © Copyright 2008 David Sieg
ALL RIGHTS RESERVED. No part of this report may be reproduced or transmitted in any form whatsoever, electronic, or mechanical, including photocopying, recording, or by any informational storage or retrieval system without express written, dated and signed permission from the author.
You are NOT free to give this report away. © 2008 David Sieg - All Rights Reserved. Making Algae Biodiesel at Home™ Liability Disclaimer: By reading this document, you assume all risks associated with using the advice given below, with a full understanding that you, solely, are responsible for anything that may occur as a result of putting this information into action in any way, and regardless of your interpretation of the advice. You further agree that our company cannot be held responsible in any way for the success or failure of your enterprise as a result of the information presented below. It is your responsibility to conduct your own due diligence regarding the safe and successful operation of your enterprise if you intend to apply any of our information in any way to your operations. In summary, you understand that we make absolutely no guarantees regarding the outcome as a result of applying this information, as well as the fact that you are solely responsible for the results of any action taken on your part as a result of this information.
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About the Author David Sieg, and Tram Nguyen authors of the Series “Down and Dirty Guides to...” Covering all aspects of making biodiesel are the Managing Directors of International Biofuel Solutions, LLC. IBS is an American company on the biofuel frontier. We are located in Ho Chi Minh City, (Saigon) Vietnam and Bangkok , Thailand.
IBS specializes in creating biotechnology solutions for developing countries. We are currently looking into the possibilities of bio-fuels using catfish oils and algae as feedstock. In addition David Sieg is a practicing teacher at technical universities in both Vietnam and Thailand. They are the webmasters of www.making-biodiesel-at-home and www.makingbiodiesel-books.com These guides were written with the intent of providing “Down and Dirty” realistic, no BS, info on all aspects of the biodiesel process. If you liked this Ebook, we’d like to hear about it. If you didn’t like it, WE’D REALLY LIKE TO HEAR ABOUT IT. Your comments will help make future editions of this ebook even better. Don’t hesitate to sound off. Send all comments, complaints, criticisms, and compliments to
[email protected] Other Books in the “Down and Dirty” Biodiesel Series:
The Encyclopedia of Making Biodiesel at home Biodiesel Recipes Biodiesel Processors Washing and Quality Testing Biodiesel Algae Biodiesel at home Home Heating with Biodiesel
Acknowledgments No work of this size and scope can be made without the input, and help of many people. Any work, by any author is a collaboration. In this respect, this work in no different. I like to thank the following people. Countless (and nameless) Vietnamese and Thai students contributed to this work in one way or another. (I’m also a teacher) They deserve credit. I’m sorry I can’t list you all by name. You know who you are, and you have my profound thanks. While your grades may not have reflected it (LOL) I couldn’t have done it without you. I owe you so much more than you know. I can honestly say I learned more from each one of you, than you probably did from me. It was my honor, and I, who benefited from knowing you. Thank YOU. Countless (and, by request, nameless) people in the open source community. People who strongly believe knowledge should be shared with everyone, not hoarded for the benefit of a few. People who silently, without thanks or fanfare, put their money where their mouth is. My hat is off to you. I feel humbled by the selfless contributions you made to me. “Thanks” is such an inadequate word when compared against the 1000’s of hours of patience, endless questions and the constant bothering I put you through. With this work, I’m trying to “pay it forward” because of you. I hope it pleases you. A big round of applause also goes to my customers, who also took the time to write to me, share their thoughts and input on this work. I keep updating it, usually every month, based on the feedback I get from you. You’ve also helped me to keep going. Your thoughts and comments have improved this work immeasurably. Keep them coming! Last but not least, my wife Tram, and my son Lennon. Who gave me the respect, privacy, and didn’t complain when I was working 16-20 hours a day for years at a time, on projects they didn’t understand, and truthfully, could care less about. Instead they gave me encouragement not to give up during long years of trials and tribulations, that contributed to this work. Again, a simple “thanks” seems so inadequate.
Introduction OK, I’m not going to BS you. Making biodiesel from algae is a whole different ballgame. First off, let’s get one thing clear, I’m not an “expert” on algae biodiesel. No one is. I’m not even sure there is such a thing. There are no textbooks to study, no college courses or degrees. In this field there is mostly interested tinker’s sharing their knowledge, or huge companies, hoarding their commercial secrets. Mostly I’m a writer and teacher with major bent towards alternative energy. If you’re used to my other books where I have taken a step-by-step approach, this ebook is a radical departure. I’ve tried to outline this process as simple as possible. Some places it worked, in other places, I have been accused of technical gibberish. I’m sorry for that. It’s a constant work in progress. But there is a reason why some things are difficult. It’s because SOME THINGS ARE DIFFICULT. For one, the methods outlined here are experimental. Trial and error in your personal situation is needed, and almost guaranteed. There is no “one-size-fits-all” in algae biodiesel. They are based on methods which have worked, but the variables involved in this undertaking, are too many, and too complex to cover in a short report such as this for all people, everywhere. I’ve tried my best though. Is this difficult? Well, for those of you who think it’s as easy as scraping the pond-scum off the bird bath and turning into heating oil, yeah, you’re in for a surprise. If you’re looking to click on a link inside this ebook and get all the algal oil you’ll ever need flowing from your computer, you’re going to be disappointed. You’re dealing with different processes here. These processes involve living organisms. When you introduce life into the equation, the capacity for variation increases dramatically. This is not a “static” process, like making biodiesel. (Mix A + B = biodiesel) It’s a dynamic process, which means it changes all the time, in every situation, because introducing a life form into the process, forces that change. On the other hand, creating biodiesel from algal oil is much easier in other ways. The trick is getting enough of it. It’s a clean oil, not waste oil. No begging for waste oil, no filtering, no dewatering, no titrating, none of the hassles involved in using waste oil. Some of the very best minds on the planet at Exxon-Mobil, at Chevron, even the US Department of Defense, are trying to work out viable method of mass producing oil from algae. They have billions of dollars to spend. They have unlimited resources. I have to admit, I don’t belong in that class of individual, either financially, or intellectually.
But I do believe it’s possible to create enough algal oil on a small scale to dramatically have an impact of your own personal energy needs. You can create enough to power your house, or small business. This work, is meant as an overview of the entire algae biodiesel process. It’s not perfect. It scratches the surface of the subject, and is meant as a starting point, not an ending. You’re literally going into the biodiesel wilderness where most fear to tread. This work, however, is meant to get you started in the right direction. You will want, and need to branch out on your own from there as your personal situation dictates. All situations are different. I generally work and make biodiesel in Southeast Asia. The problems we encounter here are totally different than say, Portland Maine, USA, or Dundee, Scotland. Temperature, humidity, salinity, type of algal strain, and many other factors come into play. Your aim in Making Algae Biodiesel at Home can and should be to create an abundant, neverending energy source that can be made, and used economically, giving back into the life-cycle, as you take something away from it, in a complete, never-ending, biological circle. Nothing wasted, everything used. Above all, don’t get discouraged. I know I’m supposed to be all “you-can-do-it” in the introduction. But it’s also important to be realistic about this project. Trial and error are inevitable, and truthfully, necessary. If you don’t have the patience of Edison, don’t try this at home, folks. One final note: This ebook is intended for home-biodieselers. Not a commercial enterprise. Yes, I have included a number of commercial and large scale applications in here, but that is to get your brain working and see what other people have done and are doing, where the big money is going. Ideas to enlarge your own algal oil production. This work is not intended as a way to set up your own algae biodiesel enterprise and retire as the next J. Paul Getty. The energy mess we are in now is going to be solved, I think, in large part by back-yard tinker’s, small-scale production and home-grown solutions. In short, you. Don’t count on the government to help you. There are too many vested interests in the industrial-complex who profit by keeping you “energy-slaves.” Their one and only passion is keeping you tied to the gas pump. Believe it. I personally respect every single one of you, more than you know, for having the courage, and the forward thinking, to even envision this goal. Let alone take steps towards it. Most people can’t even do that. You are already a minority, and heroes in my eyes. Also keep me updated on your progress...I mean that. I like hearing from you. You guys, my steady customers, have been an inspiration to me. I can’t thank you enough for your encouragement, and also for the kick in the ass when I needed it. All the best, and the absolute best of luck to you and your families. Keep in touch with me. David Sieg Bangkok, Thailand March, 2008
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How To Use This Book This book is set up to be as easy, or as difficult, as you want it to be. It is set up to give you as little detail as needed to get the job done, to giving as much detail as you could possibly want. It starts with a basic flowchart overview so that in a glance you can see the various stages and processes necessary. The “Quick Start Guide” is available to give you the essential necessary details when you need them. It provides “What” to do. The “Down and Dirty” Guides will provide most of the detail you need to actually accomplish the task, presented in an easy-to-understand, bulleted format, without a lot of details to bog you down. It provides “How” to do information. After that, come relevant details you may need, or want, for any given procedure. It goes into more depth and provides a better understanding of the “why” you do certain actions and can also be used for trouble shooting. The “Technical Data” Section is provided for an in-depth understanding of the subject, and various different ways, and means of accomplishing your goal. FIRST… Read through the entire book. At least once. If the Technical Details sections get to be a little much, then skip it. NEXT… Read the section you need to begin. Then read the “Down and Dirty” Guide for that section. Try to visualize the actions you’re about to take. •
Gather the material needed for each section before you begin.
TAKE ACTION… There is not much more to it that that. This can be as easy, or as difficult as you want to make it. My advice? Make it as easy as possible. If something doesn’t work, try again. Above all, make notes of everything you do. Note amounts, times, and durations, keep careful track of what DOESN’T work, as well as what does. It is your notes which will prove more invaluable than even this eBook. Above all, don’t give up. Trial and error and inevitable. Visualize your goal, and keep moving forward.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Book I Cultivating Algae For Biodiesel
At Home Copyright 2008 David Sieg
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Making Algae Biodiesel at home
“There is no other resource that comes even close in magnitude to the potential for making oil,” John Sheehan, energy analyst with the National Renewable Energy Laboratory (NREL) in Golden, Colo.,
“If we were to replace all of the diesel that we use in the United States” with an algae derivative,... we could do it on an area of land that’s about one-half of 1 percent of the current farm land that we use now.” ...Douglas Henston Solix CEO
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Flow chart of The Entire Algae to Biodiesel Process Examination of Examination of local algae algae and and local determination of determination of proper strain proper strain
Begin test phase Locate, isolate, optimum algae culture
Fertilize for maximum growth
Small Scale Harvest
Process into Biodiesel
Test Production Phase Build aquarium (or photobioreactor)
Cultivate Algae
Harvest algae
Oil extraction
Process into biodiesel
Begin Production Phase
Build greenhouse Or Refine photobioreactor
Cultivate algae
Harvest Algae
Process algal oil into biodiesel
Copyright 2008 David Sieg
Oil extraction
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Making Algae Biodiesel at home
Algae Overview
WITH THE INCREASING INTEREST in biodiesel as an alternative to petro-diesel, many people are now looking at the p o s s i b i l i t y o f g r o w i n g m i c r o - a l g a e a s a solution to the problem of peak oil. Micro-algae is, by a factor of 8 to 25 for palm oil. and a factor of 40 to 120 for rapeseed, the highest potential energy yield temperate vegetable oil crop. Michael Briggs at the Univ. of N. Hampshire Biodiesel group estimates that using open. outdoor, racetrack ponds, only 15,000 square miles could produce enough algae to meet all of the USA's ground transportation needs. Transportation accounts for 67% of US oil consumption according to the Atlantic Monthly, July/August 2005. We'll say more about the 15,000 square mile number below. If all of this land were in one rectangular piece, it would be 120 miles by 125 miles— about 1/7th of the area of the state of Colorado.
Gallons of Oil per Acre per Year Corn
18
Soybeans
48
Safflower
83
Sunflower
102
Rapeseed
127
Oil Palm Micro Algae
635 5000-15000
The National Renewable Energy Laboratory During the oil crisis of the 1970s, Congress funded the National Renewable Energy Laboratory (NREL) within the Department of Energy to investigate alternative fuels and energy sources. Between 1978 and 1996, the Aquatic Species Program (ASP) focused on the production of biodiesel from high lipid-content algae growing in outdoor ponds and using CO2 from coal-fired power plants to increase the rate of algae growth and reduce carbon emissions. Prior to this program, very little work had been done to understand the growth process and metabolic composition of algae. As a result of the ASP there are now some 300 species, mostly diatoms and green algae, in a collection stored at the Marine Bioproducts Engineering Center that is available to researchers interested in developing algae as an energy source.
Copyright 2008 David Sieg
Making Algae Biodiesel at home
Some results listed in the Close Out Report of the ASP are: • Under optimum growing conditions micro-algae will produce up to 4 lbs./sq. ft./ year or 15,000 gallons of oil/acre/year. Micro-algae are the fastest growing photosynthesizing organisms. They can complete an entire growing cycle every few days. •
One quad (1015 BTU or 7.5 billion gal.) of biodiesel could be produced on 200,000 ha of desert land (equivalent to 772 sq. mi., roughly 500,000 acres). (To produce one quad from a rapeseed crop would require 58 million acres or 90,000 sq. mi.)
•
The outdoor race-track pond production system is the only economically feasible approach given the cost of petroleum in 1996. (One of the problems with growing algae in any kind of pond is that only in the top 1/4" or so of the water does the algae receive enough solar radiation. So the ability of a pond to grow algae is limited by its surface area, not by its volume.)
• Algae contains fat, carbohydrates, and protein. Some of the micro-algae contain up to 60% fat. Once the fat is 'harvested'— some 70% can be harvested by pressing—what remains becomes a good animal feed or can be processed to produce ethanol. • The desert test location in New Mexico had sufficient sunlight, but low nighttime temperatures limited the ability to achieve consistently high productivity. • There were problems getting lab-cultured algae to grow in the outside pond environment. • No tests were carried out on mechanisms and procedures for harvesting the algae nor on the extraction of oils from the algae.
Copyright 2008 David Sieg
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Flow chart of The Algae Cultivation Process Examination of Examination of local algae algae and and local determination of determination of proper strain proper strain
Begin test phase
Locate, isolate, optimum algae culture
Fertilize for maximum growth
Small Scale Harvest
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Quick Start Guide Cultivation Examination of local algae and determination of proper strain
Commercial Algae
Local Algae
Advantages: • • • •
• • •
Easiest to find Easiest to maintain Cost effective Resistant to local parasites
Disadvantage:
Disadvantages • • • •
• • • •
Often difficult to identify More labor intensive Often need professional help Most native strains don’t have a high oil content Decision Made Gather Materials Start Culture Add Nutrients Maximize Growth Harvest Oil Extraction
Copyright 2008 David Sieg
Advantages: Easy to buy Can be sure of quality Consistent supply
Frequently expensive May require expertise May require more care May be labor intensive.
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A “Down and Dirty” Overview of the Process Examination of local algae and determination of proper strain
Phase One: Examination of local algae: An examination of local algae is done for a number of reasons. • What works best naturally for your environment, ultimately will eliminate problems with invasive algae down the road during the aquarium and/or open pond stage. • Easy to procure. • Easy to resupply • Local algae strains reduce costs • Local algal strains are more resistant to contamination If you’re lucky, a local strain will also have high a high lipid (oil) content. This is the ultimate goal. How do you know if a local strain is also oil bearing? You don’t, really. Until you’ve been able to identify it. One way to tell is if in your local environment you can see an “oil slick” around the algae. •
• •
•
You can also short-cut this process by going to your local university Micro-Biology Dept. and seeing which algal strains are native to your area. If a high yielding strain is available, start there. If not, try to identify a strain yourself. If this proves impossible, simply start with ANY algae from your area. This DOESN’T mean it will yield oil. (It probably won’t) but growing a local strain is worth the experience. If you can’t grow a small amount of algae, you won’t be able to grow a large amount either. If possible, and you can identify more than one species, take as many different strains as possible for testing and comparing. Buying an Algal Strain
If a local strain is not available or unacceptable, then your choices are to buy the strain you want. With a bought strain you can be sure of • • • •
Quality That it is the correct strain It should be healthy to begin with You can be sure of a supply
However the disadvantages are: • • •
Depending on the strain, they can be expensive They may not be able to resist local contamination Extra care must be taken, i.e. more labor intensive
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Gather Materials If local… •
Procure a small sample • This can be easily done. Simply go down to local bog/marsh, etc, and scoop some up, along with some water, and put into a glass or clear plastic jar. • Keep the algae in a sunlit location during the day. • If you’re going to keep it for any amount of time, add nutrients daily and stir (aerate) the mixture. • This would be a simple experiment to see if the algae can be grown easily.
If strain is commercial variety • • • • • •
Contact a local culture collection about the particular strain you’re thinking of using. Explain why you want the algae, and if they have any suggestions Ask about it’s “lipid” (Oil) value. Ask if they know of a strain in their collection with a higher lipid value. Ask about nutrients Ask about any special growing needs or techniques.
While buying an algal strain can be much more expensive, the time you save, and the expertise you gain by not “re-inventing the wheel” can be well worth the exchange.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Start Culture In a small Petri dish, or any wide mouth glass container, (Plastic peanut butter jars work pretty well.) take a small amount of algae out of your supply. • • • •
Add a small amount of distilled water, just enough so that the algal culture “floats.” Let the algae sit in the sun light as much as possible. Then adding nothing else, watch the culture for a few days
Does it grow, or does it die? • If it grows (doubles in size) with no interaction from you, stop. You’ve completed this section. • If it dies, try again. • Vary the amount of sunlight • Vary the amount of water. • Vary the amount of algae
The point of this exercise is… To get an algal specimen to grow without any outside help. If it does... • This is a strong species • This is a species which hopefully will excel with nutrient manipulation. • If it has a high lipid content, you’re well on your way to a successful project.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Add Nutrients At this point you have a strong species of algae with a high lipid content. You know.. • • • •
With a minimum of fuss and bother it will grow You’ll have an idea of how fast it will double it’s mass You’ll know the correct amount of sunlight You’ll know the correct amount of water necessary
Next you’ll want to add nutrients to see the various effects. The hope here is that they will enhance growth, and/or speed up the growth process. • • • •
Start with fish nitrates (manure) if available. Try plant food at your local aquarium shop Try dried animal manure, ground into a powder, mix with water. Try “Miracle Grow” plant food. (mixed with water)
Try using very small amounts of each in the beginning. Simply stir into or mix into the water. After you tried ONE thing. Stop. Watch what happens. (A few days) • •
In some cases, your specimen will die. If so, start again. And now you know not use that particular nutrient. If nothing happens, add another nutrient • Vary the amount of the nutrient • Vary the amount of sunlight • Vary the amount of water
What you WANT to happen is that the growth of the algae is accelerated • • •
If the algae was doubling in size every 3 days, and now it’s doubling every 1.5 days, stop. You’ve identified key nutrients and/or conditions to enhance growth. Don’t go overboard. If you’ve identified one or two things that enhance growth...stop. You’ll have plenty of time to screw this later trying to get everything perfect. :+)
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Maximize Growth In this phase, the goal is the maximize all aspects of the algal growth. By now you should know… • • • • • • •
What algal strain is best for your environment That your algal strain will grow with little or no help from you The “doubling rate” of your algal strain The amount of sunlight necessary. The amount of nutrients necessary for growth The kind of nutrients your algal species prefers The “doubling rate” with nutrients.
Now it’s time to start maximizing the growth rate. • •
To do this, you’ll use all the information you’ve learned from before. Now, vary the amounts of sunlight. • Add a Glowlux light of florescent light. • Try 6 hours of light, try 12 hours.
• • •
Vary the amount of nutrients. Add more. Add less. Vary the temperature of the water Mix the nutrients with other nutrients. • Try adding nitrates with plant food. • Try any combination of the above.
The purpose of this phase is to get as much growth from your algal species without killing it. As before, only try one difference at a time. Watch the results. Then try again. If you do terminate the algal growth, go back to what has worked, and proceed from there. Is this a time-consuming process? It can be. The point is to identify all or most aspects of accelerating growth BEFORE you have a lot of money invested. The processes here are cheap compared to what you’ll experience on a large scale.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Harvest By this time, you’ll know… • • • • • • • • • •
What algal strain is best for your environment That your algal strain will grow with little or no help from you The “doubling rate” of your algal strain The amount of sunlight necessary. The amount of nutrients necessary for growth The kind of nutrients your algal species prefers The “doubling rate” with nutrients. How to maximize the growth rate Which combinations of nutrients and sunlight are best. How much algae you can reasonably expect to grow within a given time period.
Now it’s time to harvest your algae and dry it. This step is easily accomplished. Wait until the algae culture starts the “declining relative growth” phase. (More on this later) But basically when it stops with the steep upward growth climb. At this point, remove half the algae. Depending on the size of the algae culture I’m working with, you may want to take it all, of take less than half.. •
If you want to keep experimenting, leave some of the successful culture behind.
On a small, flat mesh screen, squeeze as much water out as possible, spread the algae out, put it into the sun and let it dry. Let it dry in the sun until it changes color, until most of the water has evaporated. Depending on your location, this could be a day, or three. You want it to be the consistency of pipe tobacco. Dry, yet still a little moist If you’re the impatient type, use a hair blower, keeping it at least 1 foot (1/3 meter) away from the algae.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Oil Extraction By this time, you’ll know… • • • • • • • • • • • •
What algal strain is best for your environment That your algal strain will grow with little or no help from you The “doubling rate” of your algal strain The amount of sunlight necessary. The amount of nutrients necessary for growth The kind of nutrients your algal species prefers The “doubling rate” with nutrients. How to maximize the growth rate Which combinations of nutrients and sunlight are best. How much algae you can reasonably expect to grow within a given time period. If your algal strain will survive half extraction The ratio of “wet weight algae” to “dry weight algae”
Now you’re ready to try and extract algal oil What you’ll need. • • • • • • • •
A handful of dried algae. A garlic press Coffee filter
Tear off small pieces of the coffee filter and line the inside of the garlic press with it. Fold the algae upon itself, and pack it into the garlic press. You don’t need a lot, just keep folding as much algae into the press as you can. When the garlic press is full, simply slide the plunger over the algae, and press with all your might. You may need to fold more algae into the press, if so, put more in. Sometimes, the oil, being vicious, may take awhile to work it’s way out. Keep pressing.
If even one drop of all comes from the press. You’ve succeeded. Even one drop is a success. What will come out most likely is a green sludge. You may not even be able to tell if there is any oil in it. If so, take a small flat jar, put a small amount of water in it. Add some algal residue. If you see an “oil slick” then you know there is oil present. At this point you need to try and identify factors which encouraged the algal oil growth. If no oil comes out, then possibly… • The local strain your using has a low lipid content. (Try another strain) • You may need more algae for experimentation. (Get more algae, get a bigger press) • You may want to try buying a established high lipid strain. • More experimentation may be needed in the maximizing stage
Copyright 2008 David Sieg
Making Algae Biodiesel at home
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At this point you can extrapolate how much algae you’ll need to produce, in order to satisfy your energy requirements. For example (Purely hypothetical...don’t follow this as a guideline) • •
If you were able to produce 10 pounds of (wet) algae When dried, this was reduced to 1 pound of dry algae • AND 1 one pound of dry algae was able to expel 8 ounces (50% of dry weight) of algal oil, then… • You need 8 pounds of dry algae to produce 1 gallon of algal oil. • If you use 300 gallons of fuel per month • You’ll need to produce 2,400 pounds of dry algal mass per month
Once again, these numbers are purely hypothetical. You may find, you’ll need much less algae...or much more. The whole point is to determine whether this is indeed possible and/or feasible, for you to do this on a theoretical basis. It will also give you an idea about • Future land requirements needed. • Costs involved in building large scale • Costs involved in nutrients • Necessary size of open-pond, or photo bioreactor If all the factors are a go, and you indeed have been able to expel oil, consider it a major success. If you can’t get the numbers to work, then at this point you know NOT to go any further with this project. Your options then are... • • •
Go back to step one. Identify another algal strain, rinse and repeat... Employ professionals to help
Copyright 2008 David Sieg
Making Algae Biodiesel at home
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Choosing an Algal Strain For Oil First...a cold dose of reality. There is no “paint-by-numbers” method of doing this. There is no magic bullet. There is no “ONE” strain of algae, suitable for everyone, everywhere. Get used to it, and get over it. There are over 300,000 different strains of algae. (Some say 4 million) The vast majority of which, aren’t suitable for producing oil. Some say only 25% of KNOWN algae have been researched. I can’t possibly try to list them all. This is where the sheer weight of YOUR OWN trial and error comes in. Also there is no “one” best strain of algae, or at least none that can be agreed on. This is a hotly debated subject, so welcome to the club. Rather than pontificate, I’ll just lay it out and you can decide what is best for your situation. The largest factors concerning choosing an algae for biodiesel production: •
•
•
Choosing a strain with a high lipid (oil) content is always first and foremost. Obviously, you want to start with a strain that has the highest chance of producing a large amount of oil. Choosing the correct strain in relation to climate comes next. If you choose a warm weather algae and live in the arctic, chances are you’re doomed to failure. In terms of climate, you either need to choose a suitable strain that is best for your climate, or you’ll need to create an optimal climate for the algae by artificial means. i.e. a greenhouse. Choosing the method of cultivation that will allow the algae to maximize growth in significant amounts. You’ll need to decide in the beginning whether your plan is to use “raceway” ponds, PBR’s, Greenhouses or other, and whether your strain is suitable for that method of cultivation. • Secondary considerations include: • Availability of your selected strain. • Growth considerations: • Constant temperature needed. • Light requirements • Light patterns • Salinity (if required) • Nutrients needed • Requirements for agitation • Weaknesses of the strain you’re using.
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Choosing a Local Strain From Your Own Environment Many people think that because algae will grow in your bird bath or swimming pool, it should be a breeze to get it to grow under optimal conditions and have all the free oil (and money) your heart can desire. Picture relaxing on a beach, golden girls lighting your Cuban cigar with $100 bills in string bikinis. Wrong. It isn’t going to happen. The only way I know of choosing algae is to observe an oily sheen around the algae in your environment. This ***MAY*** indicate the presence of an oil bearing species. If you do encounter this, consider yourself extremely lucky. It is difficult to locate oil bearing species in a natural setting. The truth is, you have some serious obstacles to overcome if this is the method you want to use. The first of which is the sheer volume of known species of algae. The are approx. 300,000 strains of algae, yet only a handful are known to have a high oil content. This alone makes the outcome of a local algae project extremely uncertain. (For algal oil anyway) Another challenge you’ll need to overcome is identification of the species you have locally. Algae are usually identified at the cellular or microscope level. Once you are well versed in many types of algae you could identify them by sight, but most of us aren’t micro biologists. This means you’ll need to either take a sample to a university, or hire a professional to determine it’s characteristics. The over riding characteristic you’re looking for is lipid content. If it has a high lipid content, meaning anything over 10% of it’s DRY WEIGHT, then it may be worth considering. Local algae also have a number of advantages worth considering. If you’re lucky enough to have a local supply with a high lipid content. • •
Inexpensive to experiment with. Your environment is already perfect for reproduction of this class of algae.
No matter what kind of algae is in the local environment, it does offer also the opportunity to see if you can grow it easily. This is a good way to test your understanding as well as your ability. This experimentation stage is under appreciated in my opinion. The simple truth is, if you can’t grow a little algae, you won’t be able to grow a lot of it either later. Copyright 2008 David Sieg
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The following species listed are currently being studied for their suitability as a mass-oil producing crop, across various locations worldwide. All have a lipid content which is suitable to justify mass harvesting for biodiesel production. The bad news is, not all of these have been thoroughly tested, and/or researched for uses in biodiesel. This is the place, right here, where you’re stepping into the unknown and becoming a pioneer. For those of you with the stomach for it, fortunes are going to be made, and lost on this frontier. 1.Botryococcus Braunii 2. Chaetoceros muelleri 3. Nitzschia communis 4. Scenedesmus dimorphus 5. Euglena Gracilis 6. Prymnesium Parvum 7. Phaeodactylum tricornutum 8. Pleurochrysis carterae 9. Tetraselmis chui 10. Tetraselmis Suecica 11. Neochloris oleoabundans 12. Isocharysis galbana 13. Nannochloropsis salina 14. Dunaliella Tertriolecta Now we’ll take a look at some of these in more detail. 1. Botryococcus Braunii: This species comes up the most in biodiesel discussions of algae. Some swear by it, others swear at it. This is a “green algae.” What you’ll hear most is that it will contain up to 70% of its dry weight in oil. It is also rumored to be the predecessor to what makes up most of the world’s fossil fuel deposits. The Botryococcus braunii have green cells with dimensions of 15 to 20 micrometers and an oval shape. They form star shaped colonies. This specie has one of the highest oil productions. According to research at Flinders University in Australia, optimal growth conditions insuring reproductivity and hydrocarbon output have been created. These are: • • • •
Light intensity of 30-60 W/m^2 Average temperature of 23 degrees Celsius (73.4 degrees Fahrenheit) Salinity of 8.8% (normally defined as “brackish” waters Sunlight concentrations of 12 light, with 12 hours dark.
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Making Algae Biodiesel at home
According to Flinders University, with these conditions present, cells doubled approximately every 2 days. Almost everyone else feels doubling is about 2 weeks. The bad news about Botryococcus Brauniiis is that they jury is still out on whether this should even be considered a biodiesel strain. Many people feel this strain is unsuitable. The debate rages back and forth. Research is need here to engineer strains with faster growth and more lipid production. Phaeodactylum tricornutum is a diatom belonging to the class Bacillariophyceae. Diatoms are unicellular algae that secrete intricate skeleton made of silica. Diatoms play an important role in marine ecosystem, particularly in the biogeochemical cycling of minerals like silica, and for global carbon fixation. They can be found in both fresh water and marine environments.
Pleurochrysis carterae CCMP647 was studied by Murdoch University and found it grew well in a number of conditions, including open ponds, out door raceway ponds, photobioreactors, as well as tubular bioreactors. Lipid content ranged between 30% to 50% dry weight content.
Prymnesium parvum is a small (3000 to the inch) member of the yellow-green algae family. It has a lipid content of 22% to 38%. It is considered a “toxic” algae has been known for fish-kills. This could prove problematic if growing this species in an open pond area and it migrates into the natural habitat. Expect a visit from the local EPA with frowns on their faces and fines in their hands.
Copyright 2008 David Sieg
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Scenedesmus dimorphus. Known as a “heavy bacterium” it has a lipid content in the 16% to 40% range. This is a strain which needs to be constantly agitated when being grown. Otherwise, sediment buildup will hinder growth. Temperature range is 30-35 Celsius (86 to 95 degree Fahrenheit) Also, this species will utilize any and all light given to it. It can also be acquired from a number of public sources.
Euglena Gracilis is an interesting organism in that it is both plant and animal. It can produce its own food like a plant, yet when deprived of its food source, it can also eat others. It has a lipid content in the 14% to 20% range, and optimal growing temp. is 27 to 31 degrees Celsius. (80.6 to 87.8 degrees Fahrenheit) This strain can also be acquired easily from public sources. Another advantage is quite a bit of research has been done on growing this strain and is available.
Tetraselmis is a genus of phytoplankton. Tetraselmis has a very high lipid level, up to 45% and stimulates feeding in marine organisms using natural amino acids. Tetraselmis is green, motile, and usually grows 10 µm long x 14 µm wide.
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Making Algae Biodiesel at home
Confused? Don’t be. Try these strains first... 12 High Lipid (Oil) Species Lipid Content (oil)
Growth Medium
Price
Chlamidomonas reinhardi
21%
Soil/water
$30
Chlamidomonas moewusii
14%
Soil/water
$30
Dunaliela salina
15%
Seawater
$30
Chorella pyrenoidiosa
2%
Freshwater
$30
Nannaochloropsis
21%
Soil/seawater
$30
Coccolithophora
12%
Soil/Seawater
$30
Chlorella protothecoides
14%
Soil/seawater
$30
Chorella minutissima
44%
Seawater
$30
Porhyriduim
9.0 to 14%
Soil/water
$30
Tetraselmis
45.7%
Seawater
$30
7%
Soil/Seawater
$30
21.9%
Soil/seawater
$30
Strain
Isochrysis galbana Pleurochrysis carterae
The most inexpensive place to buy these strains is at http://www.ecogenicsresearchcenter.org/prod02.htm If you’re willing to sacrifice money to save time, this is the way to go. The owner, Marc Cardoza, is knowledgeable and is always willing to help. His prices can’t be beat...anywhere.
Copyright 2008 David Sieg
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Where To Buy Algal Strains http://www.ecogenicsresearchcenter.org/index.htm Ecogenics Research Center is a small, custom algae laboratory selling products at reasonable prices. Marc Cardoza, the owner, is very knowledgeable about algae biodiesel and able to supply any strain needed. I recommend them highly. The University of Texas also maintains a large algal depository located online at http://www.utex.org/ The Culture Collection includes approximately 3,000 different strains of living algae, representing most major algal taxa. The primary function of UTEX is to provide algal cultures at modest cost to a user community. Cultures in the Collection are used for research, teaching, biotechnology development, and various other projects throughout the world. This website contains a listing of the cultures maintained by UTEX, conditions for their long-term growth, information regarding the purchase of cultures, and various other features of UTEX. Botryococcus Culture Collection http://www.botryococcus.org/bcc/ BCC is a specific culture collection that maintains only coccoid green algae of the genus Botryococcus. The collection is actively involved in the isolation and identification of new strains. Therefore, the collection contains a number of species and subspecies in axenic cultures that were isolated from various natural habitats and may not available through other culture collections yet. In the future, strains of Botryococcus that are maintained will be available from this collection. BCC was founded in 2006 and is managed by Dr. Jürgen E.W. Polle. The Chlamydomonas Center This site provides access to Chlamydomonas genomic, genetic and bibliographic information, the Chlamydomonas culture collection, and other resources for the Chlamydomonas community. http://www.chlamy.org/
Culture Collection of Microorganisms from Extreme Environments http://cultures.uoregon.edu/default.htm The University of Oregon Culture Collection of Microorganisms from Extreme Environments (CCMEE) was created in 1999 by the consolidation of the collections of Dr. E. Imre Friedmann of Florida State University and Dr. Richard Castenholz of the University of Oregon. The newly formed CCMEE contains cultures from all over the world (e.g. Antarctica, Israel, Asia, Africa, New Zealand and North America). The majority of cultures were collected from extreme environments such as hot and cold deserts, hypersaline waters, hot springs, acidic waters, and habitats exposed to high solar irradiance. The collection represents many years of the combined work of Imre and Roseli Friedmann, Richard Castenholz and innumerable students. .
Copyright 2008 David Sieg
Making Algae Biodiesel at home
European culture collections: Czech Republic http://botany.natur.cuni.cz/algo/caup.html http://www.butbn.cas.cz/ccala/index.php France http://www.unicaen.fr/ufr/ibfa/algobank/ http://www.sb-roscoff.fr/Phyto/RCC/ http://www.pasteur.fr/recherche/banques/PCC/ Germany http://www.ccac.uni-koeln.de/ http://www.epsag.uni-goettingen.de/html/sag.html http://staff-www.uni-marburg.de/~cellbio/welcomeframe.html http://www.awi.de/en/research/research_divisions/biosciences/biological_oceanography/ diatom_centre/ Scandinavia http://www.sccap.bot.ku.dk/ Australia http://www.marine.csiro.au/algaedb/default.htm Canada http://www.botany.utoronto.ca/utcc/ http://www3.botany.ubc.ca/cccm/index.html Mexico http://www.cibnor.mx/colecciones/malgas/ialgas.php
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Japan http://www.nies.go.jp/biology/mcc/home.htm http://www.iam.u-tokyo.ac.jp/misyst/ColleBOX/IAMcollection.html http://www.wfcc.info/datacenter.html United Kingdom http://www.ccap.ac.uk/ http://www.mba.ac.uk/facilities/facilities.php?culturecollection
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Algae Growth Environments Algae are some of the hardiest organisms on earth, able to grow in a wide range of conditions. Algae are usually found in warm, damp environments, or bodies of water and thus are common on land, as well as water. However, algae are usually far more common in moist, tropical regions than dry ones, because algae lack vascular tissues and other adaptations to live on land The following are examples of natural water habitats for algae and a places to start your search. •
Billabongs & lagoons
•
Bogs, marshes & swamps,
•
Farm Dams,
•
Hot springs,
•
Lakes,
•
Ponds
•
Roadside ditches and rock pools,
•
Reservoirs,
•
Rivers,
•
Streams,
•
Salt Lagoons,
•
Salt Lakes & Marshes
Copyright 2008 David Sieg
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Put quite simply, microalgae are remarkable and efficient biological factories capable of taking a waste (zero-energy) form of carbon (CO2) and converting it into a high density liquid form of energy (algal oil). They grow anywhere and everywhere. OK, at this point, you’ve chosen an algal strain. It’s… • • • •
Native to your area (hopefully, but not absolutely necessary) But if not, you have it available from a commercial dealer. Has a high lipid (oil) content Easy to cultivate
If you haven’t been able to find a suitable local strain, then you’ve been able to buy one. At the very least, you have some ideas on a suitable strain you want to work with. Now then, what you want to know at this point is... Can you grow it artificially? You do this by setting up a small algal lab. This where you’ll be able test different species, inexpensively to get all the various factors necessary working together. Which brings us too...
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Building a “Down and Dirty” Algae Cultivation Lab You’ll be using discarded clear plastic bottles, large and small, to serve as culture flasks.
Materials needed: Material • • • • • • • • • • • • •
Obtain
Price
Clear plastic soda bottles in the two-liter size Anywhere $0.00 Granular chlorine Swimming pool supply $12.00 Dechlorinating agent Swimming pool supply $20 Pump for a 10-gallon aquarium Tropical-fish store $10 Multiport manifold Tropical-fish store $15 Stiff plastic tubing Tropical-fish store $5 0.5-micron filter http://www.millipore.com/index.do $79 for a 10-pack Micro Algae Grow http://www.aquaculture.ch/product/hatcherie/food.html $4.20 Liquid Silicate Solution http://www.aquaculture.ch/product/hatcherie/food.html $3.20 Algae samples http://www.ecogenicsresearchcenter.org/product2.htm $30 Fluorescent lamp Home improvement store $10 Discarded five-gallon jug Anywhere $0.00 Hot air gun Tool store $30
TOTAL
Copyright 2008 David Sieg
Approx: $220
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What you’re going to do: First… Sterilize everything. This is to insure there are no bacteria to contaminate your culture from the very beginning. If you overlook this step, chances are your culture will crash. • Go to your local pool supply store and purchase granular chlorine. • Dissolve as much of the granular chlorine as possible into 30 milliliters (or about an ounce) of warm water. Stir gently. • After it is dissolved, prepare a 10-to-1 dilution by mixing five milliliters (about one teaspoon) of the concentrated chlorine solution into 45 milliliters (about 8 teaspoons) of distilled water. • Try not to transfer any undissolved crystals into the sterilizing solution you are preparing. Next… •
• • •
•
Fill the two-liter soda bottles nearly to the top with either distilled water (for fresh water algae) or saltwater (for ocean algae) Add five drops of the sterilizing solution to each. Wait two hours for the chlorine to disinfect the water. Chlorine tends to evaporate quickly from solution, which means you'll have to make up a fresh batch of sterilizing fluid every time you need some. You can also add a few drops of bottled dechlorinating agent from a tropical-fish store will also do the job in no time flat.
Don't introduce your algae until you've made sure, (use a kit for testing home pools) that no chlorine is detectable in the solution. If you skip this step, you’ll kill the algae when you do put them in. OK, so far, so good… One pump for a 10-gallon home aquarium can easily aerate (mix with air) 10 soda bottle flasks. • •
Use the kind called “multiport manifold “ (Basically this a aquarium pump device with one input and many outputs) to distribute the air to the different bottles. You’ll also need some stiff plastic tubing (also available at the aquarium store) at this point. You may need to use the hot-air gun to bend the tubing. You’ll use it to inject the air into each algae culture.
Copyright 2008 David Sieg
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You should also pump it through a 0.5 micron filter Millipore http:// www.millipore.com/index.do ($79 for a 10-pack) , to keep the bacteria from invading your clean and sterilized soda bottles.
Now start feeding each soda bottle with the appropriate nutrients. • •
Aquaculture Supply (http://www.aquaculture.ch/product/hatcherie/food.html) sells Micro Algae Grow for $4.20 for cultivating most kinds of green algae Liquid Silicate Solution ($3.50) for culturing diatoms. There are directions on each package.
OK, the big day has arrived… The algae samples arrive in the mail. They’ll usually be in small plastic dishes filled with gelatin. • In order to remove the living cells, you’ll need to put the gel beneath a thin layer of your growing solution and allow it to soak for 12 hours. • Using a sterile cotton Q-Tip, the algae microorganisms should then easily rub off the gel under the gentle pressure. • Inoculate each flask with about 10 milliliters (two teaspoons) of the resulting solution. • Always make sure at every step that all your instruments are sterile and germ-free by carefully washing them with detergent and sterilizing solution and then rinsing them with distilled water. In a perfect world, or if you had a laboratory, your algae culture should be incubated at 19 degrees Celsius (about 66 degrees Fahrenheit), but truthfully, I think most people could get away with just letting them sit at room temperature. • • •
Avoid putting them in direct sunlight, (Too hot) Instead you can trying putting the flasks in front of a bright fluorescent lamp for 18 hours a day. A standard bulb of at least 2,500 lumens works fine, but some people recommend "grow -lights," which produce more realistic blue photons used in photosynthesis.
Once you get everything going, you should keep aerating (bubbling) the water on a constant basis. Give it a week or so, and your container should be dark green with algae. Once it reaches this stage the algae is mature and can be harvested. Now, be careful here, a cellular explosion can occur (exponential phase) and crash the entire culture, so don't wait too long.
Copyright 2008 David Sieg
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Extract 10 milliliters of the mature algae and start a new batch. If you do this, you'll never need to purchase another starter gel.
Scaling up… An algal lab will grow larger quantities of algae in 20-liter (five-gallon) containers called “carboys.” You can scale this whole system up. Some companies charge $100 for these transparent plastic bottles, but find a discarded five-gallon jug from a watercooler. It works just as well. You can build a special arrangement of tubing, (See the illustration) using a hot-air gun, to bend the plastic tubing. Simply heat it up, bend it how you want it, and allow it to cool. The purpose of this is to allow air into the carboys without risking contamination. OK, at this point you should be getting good at this, you have made a number of successful cultures and want to scale up. Great. Here’s what you do… • •
Fill an empty water jug with distilled water or salt water. Add five milliliters of fresh sterilizing solution.
As before, let things stand for two hours, then dechlorinate the water and test it. • •
Add the necessary nutrients and add the contents of one complete bottle of mature algae. Connect the air pump and make sure the container gets plenty of fluorescent light.
You can also track the rate of growth by using a special dipstick sold by Aquaculture Supply ($7.75). All you need to do is put the stick into the jug until the algal culture covers the black ring on the bottom of the stick, then read the depth off the scale on the side. For each species, you can then calculate the density of cells using a table supplied with the stick. After about a week, you should see definite improvement.
Copyright 2008 David Sieg
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Cultivating and Growing Botryococcus braunii (Bb) In a groundbreaking work in 2005 by Dr. Jin Qin, of the Flinders University in Australia, and made available by the Rural Industries Research and Development Corporation Dr. Qin pioneered a way to reduce the growing time of Bb from 2 weeks to 2 days. Also as Bb is considered to have upwards to 70% of it’s dry weight as oil, it becomes very interesting indeed. As I’ve pointed out before, using Bb as a fuel source and biodiesel strain is still hotly contested in some circles. Let’s put all that aside. Leave he politics to people who have the time to waste on it, and concentrate purely on that which has been studied. The objective of this study is to examine the algal growth and lipid content of B. braunii (China strain 1) under various light, temperature and salinity conditions, in an attempt to obtain the optimal culture condition for the maximum biomass and hydrocarbon production. This report in it’s entirety can be found here http://www.rirdc.gov.au
Background According to Dr. Qin, “Botryococcus braunii is a colonial green alga that is found in lakes and reservoirs in Australia and in other parts of the world. Blooms of this alga resemble a large floating mat on the water surface. This alga contains hydrocarbon up to 75% of dry weight, which can be converted into petrol, diesel or turbine fuel or other liquid or gaseous hydrocarbons. Given that Australia has large areas of available land and brackish water and high average radiant energy influx, there is a great potential to develop a source of biofuel production through cultivation of microalgae.”
Summary of Findings • • • • • •
Strain used to study: Botryococcus braunii (China 1) Optimum light regimen to sustain algal growth: 12 hours light with 12 hours dark Medium used: NaCl Algae in 0.15 M NaCl produced maximum biomass and lipid content. The generation time of algal cells was about 2 days. Optimum temperature: 23 degrees Celsius. Light intensity: 30~60 W/m2 irradiance Salinity: 8.775% medium
What does this all mean? It means if you can be duplicate his method, you have a very good method of growing a high lipid strain of algae for fuel purposes. One of the biggest advantages of using Bb is it’s high lipid content. One of the biggest drawbacks of using Bb has been it’s slow growth. What Dr. Qin did was examine and study its growth patterns and found a way to speed up the growth from 2 weeks to 2 days, while keeping the lipid content intact.
Copyright 2008 David Sieg
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“Down and Dirty” (Home Made) Fertilizers and Nutrients Let’s get real simple with this, at least in the beginning: The most limiting factors for algal growth, is • Light • Water temperature • Nitrates • Fertilizers . This is where you begin by altering, adding, or subtracting these four components. If you have access, you can also add to this list… Carbon Dioxide and Oxygen
• •
Don’t want to make your own? I hear you. You can buy commercial products that’ll help here: http://www.aquaculture.ch/product/hatcherie/food.html
Is there more to it than this? Yes, there is. You can spend a lifetime of trial and error on this one phase alone. There are scientists right now who do. But the point is to produce algal oil. Right now, the main focus is to grow algae, however simple, with a high oil content, as quickly as possible. So here is what you do... Always record and track your changes in a workbook or notebook. •
•
•
• • •
Vary the light concentrations. Add a grow light. Try different variations of time. Start at 4 hours and increase to 6 or 12 hours. What happens? Does it have a positive or negative effect on the growth rate? Vary the water temperature. Of course, you don’t want to boil the water, but algae like warm, stagnant, water environments. Act accordingly. Try “warm” or tepid water, and go up or down from there. Or try the opposite. Cool the temperature down to 50 degrees F. OK, those little algal bugs are blooming like crazy. Great. Add nitrates. The first source of life for algae is nitrate. Nitrate is in all aquariums, and is a by-product of nitrite decomposition in the aquarium. Nitrate levels as low as 10 ppm will promote algae growth. Nitrates are nothing more than fish and/or animal manure, basically. But any dried manure will do. Dry it, powder it, add it to your growth medium in water. Once you get to the aquarium stage, you can add fish to your algae farm, and they do it for you. Some people have said the commercial fertilizer “Miracle –Grow” also works wonders. Other people have used a well known plant fertilizer called “13-13-13” or “Triple 13” Get creative. Test, record. Test, record.
This is the “Down and Dirty” method of making your algae grow. For those of you who like scientific explanations, or just want more information on the above, read on...
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Growth Dynamics of Algae The growth of algae is characterized by five distinct phases : Lag or Induction phase This phase, during which little increase in cell density, or growing occurs, is can be relatively long when an algal culture is transferred from a plate to liquid culture. Cultures with exponentially growing algae have short lag phases, which can reduce the time required for up scaling. The lag in growth is thought to be the adaptation of the cell metabolism to growth, such as the increase of the levels of enzymes and metabolites involved in cell division and carbon fixation.
4
3 1. 2. 3. 2
4. 5.
5
Lag or Induction Phase Exponential Phase Declining relative growth Phase Stationary or “static” Phase Death or “Crash” Phase
1.
Exponential phase During the second phase, the cell density increases dramatically as a function of time. The specific growth rate is mainly dependent upon, and can be manipulated, depending on the algal species, light intensity and temperature. · Phase of declining growth rate Cell division slows down when nutrients, light, pH, carbon dioxide or other physical and chemical factors begin to limit growth. Stationary phase In the fourth stage the limiting factor and the growth rate are balanced, which results in a relatively constant cell density. Death or “crash” phase During the final stage, water quality deteriorates and nutrients are depleted to a level incapable of sustaining growth. Cell density decreases rapidly and the culture eventually collapses.
Copyright 2008 David Sieg
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In practice, culture crashes can be caused by a variety of reasons, including the depletion of a • • • • •
nutrient, oxygen deficiency, overheating, pH disturbance, or contamination.
The key to the success of algal production is maintaining all cultures in the exponential phase of growth.
Simple Variations to Create Algal Growth Effects: Light Algae photosynthesize, i.e. they digest inorganic carbon for conversion into organic matter. Light is the principle source of energy which creates this reaction...intensity, spectral quality and light duration need to be considered. Light intensity plays an important role, but the requirements vary greatly with the culture depth and the density of the algal culture: at higher depths and cell concentrations the light intensity must be increased to penetrate through the culture Light may be natural or supplied by fluorescent tubes. Too high light intensity (e.g. direct sun light, small container close to artificial light) may result in photo-inhibition. Also, you should be careful not to overheat or burn the algae Fluorescent tubes emitting either in the blue or the red light spectrum are used primarily as these are the most active portions of the light spectrum for replicating sunlight. The time of artificial lighting should be minimum 4 hours of light per day, although some cultivated algae develop normally under constant illumination.
pH The pH (phosphate) range for most cultured algal species is between 7 and 9, with the optimum range being 8.2-8.7. Complete culture collapse due to the disruption of many cellular processes can result from a failure to maintain an acceptable pH. On the other hand, TOO MUCH can also collapse. The latter is accomplished by adding air to the culture. In the case of high-density algal culture, the addition of carbon dioxide allows to correct for increased pH, which may reach limiting values of up to pH 9 during algal growth.
Copyright 2008 David Sieg
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Aeration/mixing Mixing is necessary to • • • •
prevent sedimentation of the algae, to ensure that all cells of the population are equally exposed to the light and nutrients, to avoid thermal stratification (e.g. in outdoor cultures) and to improve gas exchange between the culture medium and the air.
The last is of primary importance as the air contains the carbon source for photosynthesis in the form of carbon dioxide. For very dense cultures, the CO2 originating from the air (containing 0.03% CO2) bubbled through the culture is limiting the algal growth and pure carbon dioxide may be supplemented to the air supply (e.g. at a rate of 1% of the volume of air). CO2 addition furthermore buffers the water against pH changes as a result of the CO2/HCO3- balance. Depending on the size and method of the culture system, mixing is achieved by stirring daily by hand (test tubes, erlenmeyers), adding air/aerating (bags, tanks), or using paddle wheels and jetpumps (ponds). However, it should be noted that not all algal species can tolerate vigorous mixing. Or my personal method...toss a cheap aquarium bubbler into the tank.
Temperature The optimal temperature for most algal cultures is generally between 20 and 24°C, although this may vary with • •
the make up of the culture medium, the species and strain cultured.
Most commonly cultured species of micro-algae tolerate temperatures between 16 and 27°C. Temperatures lower than 16°C will slow down growth, whereas those higher than 35°C are deadly and will kill a number of species. If necessary, algal cultures can be cooled by a flow of cold water over the surface of the culture vessel or by controlling the air temperature with refrigerated air - conditioning units. This however, is quite costly.
Salinity or Salt Content Marine algae are extremely tolerant to changes in salinity. Most species grow best at a salinity that is slightly lower than that of their native habitat, which is obtained by diluting sea or salt water with tap water. Salinities of 20-24 g.l-1 have been found to be optimal. Using these simple methods you ought to be able to greatly enhance algal growth. However, if you’re a glutton for punishment, now we’re going to get real technical...
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Making Algae Biodiesel at home
Book I Technical Data
Copyright 2008 David Sieg
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Making Algae Biodiesel at home
Technical Data This next section (15 or so pages) is basically technical data included if you wish to get into extreme data analysis concerning algae. (Some people do) or want to set up an algal lab. I’m including it only to complete the subject. (not as “required” reading.) But it’s not really necessary for the “Down and Dirty” growing of algae, and truthfully could confuse the issue if you’re new to this. My recommendation? Unless you’re having a serious problem with culture crashes, and need to know why, or you simply want all the information, skip it. It’s not necessary that you understand every aspect of this to grow algae. The same as it’s not necessary for you to understand mechanical engineering in order to drive a car. When your car breaks down, of course, it’s time to get technical. But for 99% of readers...Go directly to page 53.
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Chemical Formulas for Algae Growth The most important parameters regulating algal growth are nutrient quantity and quality, light, pH, turbulence, salinity and temperature. The most optimal parameters as well as the tolerated ranges are species specific and a broad generalization for the most important parameters is given in Table 2.2. Also, the various factors may be interdependent and a parameter that is optimal for one set of conditions is not necessarily optimal for another. Culture medium/nutrients Concentrations of cells in phytoplankton cultures are generally higher than those found in nature. Algal cultures must therefore be enriched with nutrients to make up for the deficiencies in the seawater. Macronutrients include nitrate, phosphate (in an approximate ratio of 6:1), and silicate. A generalized set of conditions for culturing micro-algae (modified from Anonymous, 1991). Parameters Temperature (° C) Salinity (g.l-1) Light intensity (lux)
Range 16-27
Optima 18-24
12-40
20-24
1,000-10,000 (depends on volume and density)
2,500-5,000
Photoperiod (light: dark, hours) pH
16:8 (minimum) 24:0 (maximum) 7-9
8.2-8.7
Silicate is specifically used for the growth of diatoms which utilize this compound for production of an external shell. Micronutrients consist of various trace metals and the vitamins thiamin (B1), cyanocobalamin (B12) and sometimes biotin. Two enrichment media that have been used extensively and are suitable for the growth of most algae are the Walne medium and the Guillard’s F/2 medium . Various specific recipes for algal culture media are described by Vonshak (1986). Commercially available nutrient solutions may reduce preparation labour. The complexity and cost of the above culture media often excludes their use for large-scale culture operations. Alternative enrichment media that are suitable for mass production of microalgae in large-scale extensive systems contain only the most essential nutrients and are composed of agriculture-grade rather than laboratory-grade fertilizers .
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Making Algae Biodiesel at home
Algal culture techniques Algae can be produced using a wide variety of methods, ranging from closely-controlled laboratory methods to less predictable methods in outdoor tanks. The terminology used to describe the type of algal culture include: · Indoor/Outdoor. Indoor culture allows control over light, temperature, nutrient level, contamination with predators and competing algae, in contrast, outdoor algal systems make it very difficult to grow specific algal cultures for extended periods. · Open/Closed. Open cultures such as uncovered ponds and tanks (indoors or outdoors) are more readily contaminated than closed culture vessels such as tubes, flasks, carboys, bags, etc. · Axenic (=sterile)/Xenic. Axenic cultures are free of any foreign organisms such as bacteria and require a strict sterilization of all glassware, culture media and vessels to avoid contamination. The latter makes it impractical for commercial operations and/or home grown solutions. · Batch, Continuous, and Semi-Continuous. These are the three basic types of phytoplankton culture which will be described in the following sections. Next, we’ll summarize the major advantages and disadvantages of the various algal culture techniques.
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Advantages and disadvantages of various algal culture techniques
Culture type
Advantages
Disadvantages
Indoors
A high degree of control (predictable)
Expensive
Outdoors
Cheaper
Closed
Contamination less likely
Little control (less predictable) Expensive
Open
Cheaper
Contamination more likely
Axenic
Predictable, less prone to crashes
Expensive, difficult
Non-axenic
Cheaper, less difficult
More prone to crashes
Continuous
Efficient, provides a consistent supply of high-quality cells, automation, highest rate of production over extended periods
Difficult, usually only possible to culture small quantities, complex, equipment expenses may be high
Semi-continuous
Easier, somewhat efficient
Sporadic quality, less reliable
Batch
Easiest, most reliable
Least efficient, quality may be inconsistent
Batch culture The batch culture consists of a single inoculation of cells into a container of fertilized seawater followed by a growing period of several days and finally harvesting when the algal population reaches its maximum or near-maximum density. In practice, algae are transferred to consecutively larger culture platforms prior to reaching the stationary phase and the larger culture volumes are then brought to a maximum density and harvested. The following consecutive stages might be utilized: test tubes, then flasks, then carboys, cylinders, indoor tanks, outdoor tanks, open ponds and/.or photo bioreactors.
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The preparation of the small culture vessels is a vital step in the up scaling of the algal cultures: · wash with detergent · rinse in hot water · clean with 30% muriatic acid · rinse again with hot water · dry before use. Batch culture systems are widely applied because of their simplicity and flexibility, allowing to change species and to remedy defects in the system rapidly. Although often considered as the most reliable method, batch culture is not necessarily the most efficient method. Batch cultures are harvested just prior to the initiation of the stationary phase and must thus always be maintained for a substantial period of time past the maximum specific growth rate. Also, the quality of the harvested cells may be less predictable than that in continuous systems and for example vary with the timing of the harvest (time of the day, exact growth phase). Another disadvantage is the need to prevent contamination during the initial inoculation and early growth period. Because the density of the desired phytoplankton is low and the concentration of nutrients is high, any contaminant with a faster growth rate is capable of outgrowing the culture. Batch cultures also require a lot of labor to harvest, clean, sterilize, refill, and inoculate the containers.
Batch culture systems for the mass production of microalgae in 20,000 l tanks.
Batch culture systems for the mass production of micro-algae in 150 l cylinders.
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Making Algae Biodiesel at home
Continuous Culture The continuous culture method, (i.e. a culture in which a supply of fertilized seawater is continuously pumped into a growth chamber and the excess culture is simultaneously washed out), permits the maintenance of cultures very close to the maximum growth rate. Two categories of continuous cultures can be distinguished: Turbidostat culture, in which the algal concentration is kept at a preset level by diluting the culture with fresh medium by means of an automatic system. Chemostat culture, in which a flow of fresh medium is introduced into the culture at a steady, predetermined rate. The latter adds a limiting vital nutrient (e.g. nitrate) at a fixed rate and in this way the growth rate and not the cell density is kept constant. Laing (1991) described the construction and operation of a 40 l continuous system suitable for the culture of flagellates, e.g. Tetraselmis suecica and Isochrysis galbana . The culture vessels consist of internally-illuminated polyethylene tubing supported by a metal framework . This turbidostat system produces 30-40 l per day at cell densities giving optimal yield for each flagellate species. Continuous culture methods for various types of algae in 40 l internally-illuminated vessels (suitable for flagellates only) (modified from Laing, 1991),
Algae
Culture density Usual life of culfor highest yield ture (cells per µl) (weeks)
Tetraselmis suecica
2 000
3-6
Chroomonas salina
3 000
2-3
Dunaliella tertiolecta
4 000
3-4
20 000
2-3
Isochrysis galbana Monochrysis lutheri Pseudoisochrysis paradoxa
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Making Algae Biodiesel at home
A chemostat system that is relatively easy and cheap to construct is utilized by Seasalter Shellfish Co. Ltd, UK The latter employ vertical 400 l capacity polyethylene bags supported by a frame to grow Pavlova lutheri, Isochrysis galbana, Tetraselmis suecica, Phaeodactylum tricornutum, Dunaliella tertiolecta, Skeletonema costatum. One drawback of the system is the large diameter of the bags (60 cm) which results in self-shading and hence relatively low algal densities. The disadvantages of the continuous system are its relatively high cost and complexity. The requirements for constant illumination and temperature mostly restrict continuous systems to indoors and this is only feasible for relatively small production scales. Continuous culture of micro-algae in plastic bags. Detail (right) shows inflow of pasteurized fertilized seawater and outflow of culture.
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Isolating/obtaining and maintaining of cultures Sterile cultures of micro-algae used for aquaculture purposes may be ob tained from specialized culture collections. Alternatively, the isolation of endemic strains could be considered because of their ability to grow under the local environmental conditions. Isolation of algal species is not simple because of the small cell size and the association with other species. Several laboratory techniques are available for isolating individual cells, such as serial dilution culture, successive plating on agar media and separation using capillary pipettes. Bacteria can be eliminated from the phytoplankton culture by washing or plating in the presence of antibiotics. The sterility of the culture can be checked with a test tube containing sea water with 1 g.l-1 bactopeptone. After sterilization, a drop of the culture to be tested is added and any residual bacteria will turn the bactopeptone solution turbid. The collection of algal strains should be carefully protected against contamination during handling and poor temperature regulation. To reduce risks, two series of stocks are often retained, one which supplies the starter cultures for the production system and the other which is only subjected to the handling necessary for maintenance. Stock cultures are kept in test tubes at a light intensity of about 1000 lux and a temperature of 16 to 19°C. Constant illumination is suitable for the maintenance of flagellates, but may result in decreased cell size in diatom stock cultures. Stock cultures are maintained for about a month and then transferred to create a new culture line.
Sources of contamination and water treatment Contamination with bacteria, protozoa or another species of algae is a serious problem for monospecific/axenic cultures of micro-algae. The most common sources of contamination include the culture medium (sea water and nutrients), the air (from the air supply as well as the environment), the culture vessel, and the starter culture. Seawater used for algal culture should be free of organisms that may compete with the unicellular algae, such as other species of phytoplankton, phytophagous zooplankton, or bacteria. Sterilization of the seawater by either physical (filtration, autoclaving, pasteurization, UV irradiation) or chemical methods (chlorination, acidification, ozonization) is therefore required. Autoclaving (15 to 45 min. at 120°C and 20 psi, depending on the volume) or pasteurization (80°C for 1-2 h) is mostly applied for sterilizing the culture medium in test tubes, erlenmeyers, and carboys.
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Making Algae Biodiesel at home
Semi-continuous culture The semi-continuous technique prolongs the use of large tank cultures by partial periodic harvesting followed immediately by topping up to the original volume and supplementing with nutrients to achieve the original level of enrichment. The culture is grown up again, partially harvested, etc. Semi-continuous cultures may be indoors or outdoors, but usually their duration is unpredictable. Competitors, predators and/or contaminants and metabolites eventually build up, rendering the culture unsuitable for further use. Since the culture is not harvested completely, the semi-continuous method yields more algae than the batch method for a given tank size.
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Book II Building a Fresh Or Salt Water Aquarium
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Introduction Some people opt for skipping this stage, and going directly to building an open pond or a photobioreactor. Personally, I think this is a mistake. The purpose of building an aquarium in the beginning is to understand the characteristics and growth habits of your algal species before you commit to a large scale project. It gives you increased knowledge about your species, increased experience, and it’s suitability for a particular project. Like I’ve said many times before now...If you can’t grow a small amount, you won’t be a able to grow a large amount. But it’s your money. Quite a few people have skipped the open pond, with it’s drawbacks, and simply built a number of what basically are large aquariums. Some of the advantages are: • • • • • • •
Aquariums are easy to build, and cheap to buy. Parts are easily obtainable Allows you to re-create your algal specimens on a larger scale Gives you increased knowledge on nutrients and growth cycle. Gives you necessary knowledge on larger scale projects, costs, etc. Able to spot problems and/or solutions before a large investment of time and money. At this stage, if major mistakes are found, it’s easy to return to the beginning and start over.
In short, taking this extra step in the beginning, while time consuming, can head off multiple problems down the road when you start having costly and time consuming mistakes, that could have been headed off in the experimental stage. You can also, instead of building an aquarium, simply go and buy one. You can easily buy an aquarium cheaply at… • • • •
Ebay In your local paper Garage sales GoodWill/Salvation Army
The plans presented here are simply to get you going in the right direction as cheaply as possible. There is nothing that says you have to follow them. If you can find a free aquarium of any size, then use that.
Copyright 2008 David Sieg
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Building a Fresh/Salt Water Aquarium How To Calculate What Glass Thickness to Use The basic nuts and bolts of building a glass /acrylic aquarium for either salt or fresh water use are pretty straightforward: • • • • • •
Plan ahead. Measure accurately. Prepare the glass and/or acrylic. Use the right adhesive. Apply the adhesive correctly. Install the glass so as to have continuous, bubble-free seams.
The only difference in building a larger tank compared to a smaller one, of say 55 gallons or less in size, is that the bonding process must be near perfect, and the glass thickness must be enough to withstand the added water pressure with a significant margin of error for the unexpected Once the basics of construction are mastered, the biggest concern most people have with building their own custom aquarium is determining the right glass thickness. Using glass which is too thick means spending more money than you need to, and too thin means spending sleepless nights listening for the telltale sounds of cracking glass and exploding water. There are a few ways in which you can economize on the construction of your new aquarium with little to no loss in strength or utility, but first let's cover some important factors about glass. About Glass Quality, Characteristics & Thickness Because of the differences of the manufacturing process, the strength of glass can vary, which means a safety factor should be used when considering glass thickness. The commonly used safety factor is 3.8. This is not an absolute guarantee, but a rule of thumb. It should remove all risk of glass failure other than that created by damaged or very poor quality glass. Scratches and chips in the glass will be the main cause of failure at this point.
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Aquarium Glass Thickness Calculator Below, the top row is the length of the tank, the left column indicates the depth or height of the tank. To figure the glass thickness to use for constructing your tank, find the length of the tank you’d like to build in the top row (indicated in feet and cm - centimeters), then run your finger down that column until you reach the height of the tank you’d like (indicated in inches and cm). Glass thickness is indicated in mm (millimeters), with the number in parenthesis below indicating the Safety Factor.
2' 62cm 15" 40cm
18" 46cm
21" 53cm
24" 61cm
27" 69cm
30" 76cm
33" 84cm
36" 92cm
Copyright 2008 David Sieg
6mm (3.38) 6mm (2.91) 9mm (6.56) 6mm (1.79) 9mm (4.01) 6mm (2.0) 9mm (4.5) 9mm (2.96) 12mm (5.26) 9mm (2.30) 12mm (4.06) 12mm (2.91) 16mm (5.18) 12mm (2.22) 16mm (3.95)
3' 92cm
4' 122cm
5' 152mm
6' 7' 183cm 213cm
8' 244cm
6mm (3.09)
6mm (2.92)
6mm (2.92)
6mm 6mm (2.92) (2.92)
6mm (2.92)
6mm (2.37) 9mm (5.33)
6mm (2.05) 9mm (4.61)
6mm (2.05) 9mm (4.61)
6mm 6mm (2.05) (2.05) 9mm 9mm (4.61) (4.61)
6mm (2.05) 9mm (4.61)
6mm (1.79) 9mm (3.26)
9mm (2.98) 12mm (5.30)
9mm (2.82) 12mm (5.02)
9mm 9mm (2.82) (2.82) 12mm 12mm (5.02) (5.02)
9mm (2.82) 12mm (5.02)
9mm (2.76) 12mm (4.92)
9mm (2.25) 12mm (4.0)
9mm (2.05) 12mm (3.45)
9mm 9mm (1.95) (1.95) 12mm 12mm (3.46) (3.46)
9mm (1.95) 12mm (3.46)
12mm (3.24) 12mm (5.26)
12mm (2.63) 16mm (4.67)
12mm (2.40) 16mm (4.27)
12mm (2.27) 16mm (4.04)
12mm (2.27) 16mm (4.04)
12mm (2.27) 16mm (4.04)
12mm (2.42) 16mm (4.30)
12mm (1.97) 16mm (3.50)
12mm (1.97) 16mm (3.50)
12mm (1.80) 16mm 16mm (3.00) (3.20)
16mm (3.00)
12mm (1.79) 16mm (3.19)
16mm (3.19) 20mm (4.98)
16mm (2.59) 20mm (4.04)
16mm (2.37) 20mm (3.70)
16mm (2.24) 20mm (3.50)
16mm (2.24) 20mm (3.50)
12mm (2.21) 16mm (3.95)
16mm (2.42) 20mm (3.79)
16mm (1.97) 20mm (3.08)
16mm (1.97) 20mm 20mm (2.81) (3.08)
20mm (2.67)
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Use the Glass Thickness Calculator to get a general idea of the glass thickness you’ll need for your tank. Many people think that the 3.8 safety factor is a bit of an overkill for their particular tank and location (i.e. low traffic in a protected area), and are comfortable with a lower factor. How To Go “Down and Dirty” on Construction We'll use the basic 4' long x 15" high 55 gallon tank, which is an average size that most of us are familiar with. This tank is normally constructed of 1/4" (6mm) glass, that according to the figures in the glass thickness calculator has a safety factor of 2.92. Many people have found that they can increase the safety factor for a given thickness and tank size by using a 4" wide glass brace, running from front to back of the top of the glass, or put another way, turning their tank into two 2' tanks, increasing the safety factor to 3.38. Rather than go to a thicker glass to increase the safety factor, you can economize on construction in this manner. You can also design your tank stand so that it supports the entire bottom of the tank by using a Styrofoam or polystyrene pad between the tank and stand. The pad will keep the tank from failing which can be caused by dirt or grit on the stand surface. If the tank bottom is fully supported, you can also use a thinner piece of glass for the tank bottom, since the stand will be adding strength and support, keeping the glass from bending. Another idea is to compute the required thickness for the end pieces of your tank. In all likelihood, the required thickness will be less than the longer front and rear pieces of glass. The overall point here is to make sure you have adequate support UNDER your tank. Working With Silicone Glass prep and proper installation of the pieces is critical when you are building your aquarium, but even more so when constructing a larger sized tank. These silicone tips can help you avoid common mistakes made when one is working with and applying aquarium silicone. •
Apply silicone on the glass, by running a continuous 1/4" bead, with no gaps or bubbles.
•
For the best results, apply only as much silicone as you can work with in 3 to 5 minutes. After this the silicone tends to dry out and skin over and won't bond well to the glass.
•
Laying down a bead of silicone on the bottom glass for the rear and one side glass piece, and on one side edge of the back piece, installing the back glass piece on the bottom, then the side piece to the bottom and rear piece worked well.
•
When any section to be joined has been set into place, the silicone needs to be allowed to set and harden.
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Starting at one end of a joined section, press the tip of your index finger down into the silicone, then firmly and evenly, without lifting your finger, run it along the full length of the siliconed joint at a slight angle. Secure the joined section into place with duct tape. Don’t worry about wiping away any extra silicone, it can be trimmed off once the silicone has fully dried. The supporting surface of the tank base must be very level. On very large aquariums this is difficult to do, and self leveling filler should be used between the polystyrene and the base. Apply this just prior to fitting the aquarium to the base so that the aquarium’s weight levels out any less than perfect spots. Time is needed for the filler to level and fully dry before the aquarium is filled with water. Materials List for building tank Aside from 1 bottom, 1 front, 1 back, and 2 end pieces of glass, you will need the following to build your aquarium. • • • • • • • •
•
Single edged razor blades. Acetone. A non-toxic 100% silicone sealant. We have used NAPA brand (part #765-1336) with good results for years, but we recommend All-Glass® Brand 100% Silicone Sealant or a similar type product. A roll of paper towels. A washable felt tip marker. A roll of duct tape. Some emery cloth or silicone carbide sandpaper. For a larger aquarium above 30 gallons in size, you should install at least one "support brace" at the center of the tank. You do this by cutting a six inch wide piece of glass measured to fit to the "outside" edges of the front and back pieces, then attach it into place with silicone. For extra strength you can join and glue two brace pieces together using silicone, or particularly for longer tanks, install two separate brace pieces of glass equal distances from each end of the tank. Some like to use the multiple brace set-up, because this automatically builds in a place to sit one or two light strips/hoods on top of the tank Single Support Brace Placement B R A C E
Top view
Multiple Support Brace Placement B R A C E
Copyright 2008 David Sieg
B R A C E
B R A C E
•
.
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140 Gallon Tank Plans
The purpose of building a larger tanks may seem redundant, however it’s not. You may be thinking, you can skip this part. (I did) From experience...Don’t. The purpose is... • • • • • •
To see if you algal strain still holds it lipid (oil content) value in higher volumes. (It should) To refine nutrients, and/or process on a larger scale. This makes sure your figures are correct when the time comes for large scale production. To see if your algal strain will be able to defend itself from contamination by themselves. To make sure all calculations are correct, and/or make corrections. To identify and correct any weaknesses in your process. To fine-tune any production issues at a small scale, before moving on to a bigger volume where mistake and omissions are more costly.
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• • • •
140-GALLON ALGAE TANK CONSTRUCTION (1) Length:=96 inches (94.5 inches inside) (2) Width: = 24 inches (22.5 inches inside) (3) Height: = 16 3/4 inches (16 inches inside) (4) Water capacity = (.75-inch freeboard): 140 GALLON
96”
•
16.75”
24
”
Caution: Do not make over 18” deep with 1/4 inch Glass. Tools • • • • • • •
Portable circular or table power saw Screw gun, with Phillips bit Orbital or belt sander, with medium grit Caulking gun (4)- 4-inch paint brushes, one for each day of painting (2)- 16-inch stanchions (anything of this height, used to support the plywood pieces during construction) (3)-6 Various containers for mixing glue, putty, and paint
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Tank 2 140-GALLON ALGAE TANK CONSTRUCTION Materials List (For building two [2] tanks) • • • • • • • • • • • •
(3)- 4-foot by 8-foot sheets, 3/4 inch, AC EXTERIOR plywood (2)- 94-inch by 14-inch glass, 1/4-inch plate (1).5-pounds, 2-inch drywall screws (Approx. 240 count) (l)-two-can container, Resorcenol waterproof glue (l)-gallon, autobody putty w/ hardener (5)- gallons, two-part epoxy paint (2)-tubes, silicon caulking, non-toxic aquarium suitable (l)-gallon, Xylene glass cleaner (1)- pint, commercial glass cleaner (6)-sheets, 120 grit sandpaper (2)-sheets, 220 grit sandpaper (2)-packs, paper towels Sufficient for more than two tanks
CUTTING LIST Plywood Cut List (Sufficient to build two [2] tanks) • • • • • •
(2) 24-inch by 8-foot (bottom piece) (2) 16-inch by 8-foot (back piece) (4) 3-inch by 8-foot (upper & lower face frames) (4) 3-inch by 10-inch (left & right face frames) (4) 16-inch by 22 1/2-inch (end pieces) (2) 12-inch by 22 1/2-inch (top brace)
Single Tank Assembly • • •
Examine all plywood looking for rough or flawed edges, this could affect tank integrity. Sand as needed. Lay bottom piece flat on the 16-inch stanchions or support base . Apply glue along all four edges of bottom piece, sufficiently heavy to accommodate the edges of the back piece, end pieces, and face frame.
Glue
Base
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Making Algae Biodiesel at home • •
•
Turn bottom piece over, glue side down, centered on stanchions so that all edges of bottom piece are accessible. Raise back piece up under bottom piece, mating long edge of back piece into glue along edge of bottom piece. Make sure that edges are flush and even, and that they make a 90degree corner. Use a corner square if necessary Using screw gun, screw back piece to bottom piece, inserting 2-inch drywall screws at 3 -inch intervals along entire length. INSURE THAT ALL SCREWS ARE FULLY SEALED, AND TIGHT. Screw bottom piece to back piece
Screws go Here
• •
Glue along one 16 inch edge of each end piece. Raise each end piece up under bottom piece, and screw tightly to both bottom piece and back piece. Place drywall screws at three inch intervals along the bottom piece.
Screw ends to bottom piece to back piece
•
•
Glue along inside edges of face frame, where they will be joined with the end pieces. Raise lower face frame up under remaining edge of bottom-piece, and screw into place to bottom piece and end pieces. Use three screws in each end, and normal three-inch intervals along length. Insure that all edges are flush, and tight, after final tightening of screws. Note. You should wipe any extra glue away from all joints after you’ve finished tightening the final screws.
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•
• • • •
Turn partially-completed tank right side up and inspect.. All pieces screwed together should rest on the bottom piece, this will create the strongest possible base. If this is not the case, quickly disassemble the pieces before the glue sets, and reassemble properly. Turn the tank face-up . Apply glue to FRONT edges of the end pieces. Lay upper face frame in place, and screw to edge pieces, using three screws in each end. Check short face frame pieces for proper fit, sanding if necessary. THEY MUST FIT TIGHTLY WITHOUT PULLING UPPER AND LOWER FACE FRAME PIECES APART.
Screw front pieces to aquarium
• • • •
Apply glue to ends of short face frame pieces. Lay short face frame pieces into place, and screw firmly to end pieces, insuring that the outer edges are flush with the ends of the tank. Check all work, wipe away excess glue, and making sure that corners are square, true, and not pulled open by later construction. Allow to dry overnight if possible.
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TANK PAINTING
Single Tank Painting -For all processes using epoxy paint, you should use proper precautions: • • • •
1. No Smoking. Epoxy is flammable. 2. Don’t breathe fumes, use a mask if necessary. 3. Don’t let the brushes dry. 4. Apply the paint in a well ventilated area. Fumes can be highly toxic
Apply epoxy paint to all exposed wood surfaces of tank. •
Spread a thin coat of paint, while painting the wood surfaces completely, because the paint runs easily.
•
Allow coat to dry overnight.
•
Fill all cracks and holes with auto body putty, making as smooth a surface as possible.
•
Sand entire surface, using 120-grit paper or power sander, and apply second coat.
•
Again, insure that the coat is as thin as possible, to avoid running paint. Use the body putty to correct any defects or holes in the plywood
SANDING DETAILS •
Use 120-grit sandpaper for sanding the first and second coats of epoxy paint.
•
Use the 220-grit for sanding the third coat, to prepare for the final coat. (If you’re using a power sander, then the sanding pressure is less for the last coat.) Rinse and repeat until four coats of the epoxy paint are applied.
•
Allow tank to dry in well-ventilated, warm area for 24 hours before proceeding.
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Glass Installation Single Tank Glass Installation -•
Turn tank face down on flat surface, making sure that entire face frame is supported.
•
Use 220-grit sandpaper to rough up a two-inch strip of the epoxy paint on the inside of the tank, around the glass opening. This rough area will serve as a bonding area for the silicon glue.
•
Sand all corners of the glass piece, to avoid later injury to either workers or fish.
•
Clean entire surface, and edges, of glass piece with Xylene cleaner, and then commercial glass cleaner.
•
Apply 1/2-inch bead of silicon caulking around entire opening in face frame, on inside of tank. The bead should be approximately one inch from edge of opening, except along the top, and there the bead should be approximately one-half inch from edge of opening.
3/4” inch plywood
Silicon all inside edges
Glass
End view
A.
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•
Install glass on inside of tank, insuring that the lower edge of the glass is resting full-length against bottom piece of tank for support.
•
Press evenly on glass to remove all bubbles and gaps from silicon caulking seal.
•
Recaulk glass, along all edges. Pressing caulking in with finger firmly into the corner formed by glass and face frame. Final caulking seal should be smooth, rounded, and gap and bubble free. Wipe any excess caulking away after seal is finished.
FINAL FINISH Single Tank Construction Procedure, Final Assembly Points •
Using three screws for each end of brace, install tank top brace, centered, spanning from top, inside edge of back piece to top inside edge of upper face frame.
•
Apply heavy bead of silicon caulking into all interior corners of tank, again smoothing the seal with finger, removing all gaps and bubbles, and wiping away excess caulking when finished.
•
Allow tank to dry for 48 hours in warm, dry area before adding water.
Copyright 2008 David Sieg
Making Algae Biodiesel at home
Why Leaks Occur, and Common Mistakes to Avoid When Making Repairs A couple of disadvantages to having a glass aquarium is the risk of leaking and glass breakage to occur. As for leaks, most are usually caused by a flaw or failure in the sealant, either during building of the tank, or over time the sealant becomes weak and begins peeling away from the glass. These leaks are the small pin hole size, up to and including a major seam blowout, like ones that result in a soaked carpet, and a ruined room. Usually pin hole sized leaks can be fixed from the outside, without having to totally drain or tear the whole tank apart, but for major leaks or glass breakage, this requires some reconstruction of the tank. The good news? Repairing a leak is usually not a difficult task, whether it be a major or a minor one. Some “rule of thumb” tips... • • • • • • • •
Don't use the wrong kind of silicone sealant; use only a non-toxic 100% silicone sealant appropriate for aquarium use. Not cleaning and preparing the glass surface properly or adequately enough. Not pinpointing the exact location of where a small leak is coming from. Water will always be present at the bottom of the tank (gravity rules), but the source may be somewhere else up higher or sideways along the joint or seam. Not repairing a large enough area up, down, or around where the actual leak generates from. Not using enough silicone sealant. Not allowing the silicone to dry long enough. Not aligning or placing the glass pane edges flat and evenly together. Don't make major repairs under humid conditions. Duct tape will not stick to glass when it is humid, therefore, the glass may move before the silicone can set up. Humidity slows the silicone curing process as well.
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List of Items Needed for Making Repairs Here is a list of items that you will need for repairing minor or major leaks in glass aquariums, as well as for building a tank from scratch. • • • • • • •
Single edged razor blades. Acetone. A non-Toxic 100% silicone sealant. We have used NAPA (part #765-1336) with good results for years, or use All-Glass® Brand 100% Silicone Sealant or a similar type aquarium sealant. Paper towels. A washable felt tip marker. For repairing major leaks or building a DIY aquarium, a roll of duct tape. For building an aquarium, some emery cloth or silicone carbide sandpaper.
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Section III Building an Algae Green House
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Quick Start Guide Decide if greenhouse or Photobioreactor work best in your situation
Photobioreactor
Greenhouse or Open Pond
Advantages: • • •
• • •
Easiest to build Easiest to maintain Cost effective
• •
Disadvantages • • • •
Requires more land Contamination difficult to control (Open Pond) Not as efficient as PBR More labor intensive
Advantages: Requires less land Self-contained Can be set to run Automatically Climate not an issue Contamination controllable Disadvantage:
• • •
More technologically challenging. May require expertise Harder to build.
Decision Made
Gather Materials
Gather Materials
Build Open pond/ Greenhouse
Build Photobioreactor
Cultivate
Cultivate
Harvest
Harvest
Oil Extraction
Oil Extraction
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Production Stage Part 1
Begin Production Phase
Build greenhouse Or Refine photobioreactor
Copyright 2008 David Sieg
Cultivate algae
Harvest Algae
Oil extraction
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Greenhouses and Photo-Bioreactors Growing Algae in Green Houses: A variation on the basic "open-pond" system is to close it off, to cover a pond or pool with a greenhouse. While this usually results in a smaller system, it does take care of many of the problems associated with an open pond system. For me personally, this is the way to go, for many reasons... •
It allows more species to be able to be grown,
•
it allows the species that are being grown to stay dominant, and it extends the growing season, only slightly if unheated, and if heated it can produce year round.
Greenhouses can be modified to produce algae all year round. The surface area limitation which applies to ponds could be overcome in a greenhouse by adding a third layer of plastic inside the other two layers over which the pond water could flow in a thin enough film that it would receive enough solar radiation to grow algae. This should allow the greenhouse to produce more algae than the surface area of a normal pond would. This mechanism for exposing the pond water to sunlight is similar to that employed by GreenFuel Technologies. The greenhouse would also overcome two problems observed in the ASP trials in outdoor ponds—the greenhouse allows for better control of both the temperature and the air in the greenhouse. This should allow optimum growth as well as eliminate the possibility of contamination with local algae. The downside, of course, is the cost associated with heating and/or cooling the greenhouse. The best of all possible worlds? A photo bioreactor inside a greenhouse (see above) This way you’re able to enjoy the benefits of each, while limiting the downsides of each.
Copyright 2008 David Sieg
Making Algae Biodiesel at home
Planning and Building a Algae Greenhouse Location The greenhouse should be located where it gets maximum sunlight. The first choice of location is the south or southeast side of a building or shade trees. Sunlight all day is best, but morning sunlight on the east side is sufficient for plants. Morning sunlight is most desirable because it allows the plant's food production process to begin early; thus growth is maximized. An east side location captures the most November to February sunlight. The next best sites are southwest and west of major structures, where plants receive sunlight later in the day. North of major structures is the least desirable location and is good only for plants that require little light. Deciduous trees, such as maple and oak, can effectively shade the greenhouse from the intense late afternoon summer sun; however, they should not shade the greenhouse in the morning. Deciduous trees also allow maximum exposure to the winter sun because they shed their leaves in the fall. Evergreen trees that have foliage year round should not be located where they will shade the greenhouse because they will block the less intense winter sun. You should aim to maximize winter sun exposure, particularly if the greenhouse is used all year. Remember that the sun is lower in the southern sky in winter causing long shadows to be cast by buildings and evergreen trees. Good drainage is another requirement for the site. When necessary, build the greenhouse above the surrounding ground so rainwater and irrigation water will drain away. Other site considerations include the light requirements of the plants to be grown; locations of sources of heat, water, and electricity; and shelter from winter wind. Access to the greenhouse should be convenient for both people and utilities. A workplace for potting plants and a storage area for supplies should be nearby.
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Types of Greenhouses A home greenhouse can be attached to a house or garage, or it can be a freestanding structure. The chosen site and personal preference can dictate the choices to be considered. An attached greenhouse can be a half greenhouse, a full-size structure, or an extended window structure. There are advantages and disadvantages to each type. Attached Greenhouses Lean-to. A lean-to greenhouse is a half greenhouse, split along the peak of the roof, or ridge line Lean-tos are useful where space is limited to a width of approximately seven to twelve feet, and they are the least expensive structures. The ridge of the lean-to is attached to a building using one side and an existing doorway, if available. Lean-tos are close to available electricity, water and heat. The disadvantages include some limitations on space, sunlight, ventilation, and temperature control. The height of the supporting wall limits the potential size of the lean-to. The wider the lean-to, the higher the supporting wall must be. Temperature control is more difficult because the wall that the greenhouse is built on may collect the sun's heat while the translucent cover of the greenhouse may lose heat rapidly. The lean-to should face the best direction for adequate sun exposure. Finally, consider the location of windows and doors on the supporting structure and remember that snow, ice, or heavy rain might slide off the roof or the house onto the structure.
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Even-span. An even-span is a full-size structure that has one gable end attached to another building It is usually the largest and most costly option, but it provides more usable space and can be lengthened. The even-span has a better shape than a lean-to for air circulation to maintain uniform temperatures during the winter heating season. An even-span can accommodate two to three benches for growing crops.
Window-mounted. A window-mounted greenhouse can be attached on the south or east side of a house. This glass enclosure gives space for conveniently growing a few plants at relatively low cost . The special window extends outward from the house a foot or so and can contain two or three shelves.
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Freestanding Structures Freestanding greenhouses are separate structures; they can be set apart from other buildings to get more sun and can be made as large or small as desired A separate heating system is needed, and electricity and water must be installed. The lowest cost per square foot of growing space is generally available in a freestanding or even-span greenhouse that is 17 to 18 feet wide. It can house a central bench, two side benches, and two walkways. The ratio of cost to the usable growing space is good. When deciding on the type of structure, be sure to plan for adequate bench space, storage space, and room for future expansion. Large greenhouses are easier to manage because temperatures in small greenhouses fluctuate more rapidly. Small greenhouses have a large exposed area through which heat is lost or gained, and the air volume inside is relatively small; therefore, the air temperature changes quickly in a small greenhouse. Suggested minimum sizes are 6 feet wide by 12 feet long for an even-span or freestanding greenhouse.
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Frames Greenhouse frames range from simple to complex, depending on the imagination of the designer and engineering requirements. The following are several common frames (Figure 3). Quonset. The Quonset is a simple and efficient construction with an electrical conduit or galvanized steel pipe frame. The frame is circular and usually covered with plastic sheeting. Quonset sidewall height is low, which restricts storage space and headroom. Gothic. The gothic frame construction is similar to that of the Quonset but it has a gothic shape (Figure 3). Wooden arches may be used and joined at the ridge. The gothic shape allows more headroom at the sidewall than does the Quonset. Rigid-frame. The rigid-frame structure has vertical sidewalls and rafters for a clear-span construction. There are no columns or trusses to support the roof. Glued or nailed plywood gussets connect the sidewall supports to the rafters to make one rigid frame. The conventional gable roof and sidewalls allow maximum interior space and air circulation. A good foundation is required to support the lateral load on the sidewalls. Post and rafter and A-frame. The post and rafter is a simple construction of an embedded post and rafters, but it requires more wood or metal than some other designs. Strong sidewall posts and deep post embedment are required to withstand outward rafter forces and wind pressures. Like the rigid frame, the post and rafter design allows more space along the sidewalls and efficient air circulation. The A-frame is similar to the post and rafter construction except that a collar beam ties the upper parts of the rafters together.
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Coverings Greenhouse coverings include long-life glass, fiberglass, rigid double-wall plastics, and film plastics with 1- to 3-year lifespans. The type of frame and cover must be matched correctly. Glass. Glass is the traditional covering. It has a pleasing appearance, is inexpensive to maintain, and has a high degree of permanency. An aluminum frame with a glass covering provides a maintenance-free, weather-tight structure that minimizes heat costs and retains humidity. Glass is available in many forms that would be suitable with almost any style or architecture. Tempered glass is frequently used because it is two or three times stronger than regular glass. Small prefabricated glass greenhouses are available for do-it-yourself installation, but most should be built by the manufacturer because they can be difficult to construct. The disadvantages of glass are that it is easily broken, is initially expensive to build, and requires must better frame construction than fiberglass or plastic. A good foundation is required, and the frames must be strong and must fit well together to support heavy, rigid glass. Fiberglass. Fiberglass is lightweight, strong, and practically hailproof. A good grade of fiberglass should be used because poor grades discolor and reduce light penetration. Use only clear, transparent, or translucent grades for greenhouse construction. Tedlar-coated fiberglass lasts 15 to 20 years. The resin covering the glass fibers will eventually wear off, allowing dirt to be retained by exposed fibers. A new coat of resin is needed after 10 to 15 years. Light penetration is initially as good as glass but can drop off considerably over time with poor grades of fiberglass. Double-wall plastic. Rigid double-layer plastic sheets of acrylic or polycarbonate are available to give long-life, heat-saving covers. These covers have two layers of rigid plastic separated by webs. The double-layer material retains more heat, so energy savings of 30 percent are common. The acrylic is a long-life, non-yellowing material; the polycarbonate normally yellows faster, but usually is protected by a UV-inhibitor coating on the exposed surface. Both materials carry warranties for 10 years on their light transmission qualities. Both can be used on curved surfaces; the polycarbonate material can be curved the most. As a general rule, each layer reduces light by about 10 percent. About 80 percent of the light filters through double-layer plastic, compared with 90 percent for glass. Film plastic. Film-plastic coverings are available in several grades of quality and several different materials. Generally, these are replaced more frequently than other covers. Structural costs are very low because the frame can be lighter and plastic film is inexpensive. Light transmission of these film-plastic coverings is comparable to glass. The films are made of polyethylene (PE), polyvinyl chloride (PVC), copolymers, and other materials. A utility grade of PE that will last about a year is available at local hardware stores. Commercial greenhouse grade PE has ultraviolet inhibitors in it to protect against ultraviolet rays; it lasts 12 to 18 months. Copolymers last 2 to 3 years. New additives have allowed the manufacture of film plastics that block and reflect radiated heat back into the greenhouse, as does glass which helps reduce heating costs. PVC or vinyl film costs two to five times as much as PE but lasts as long as five years. However, it is available only in sheets four to six feet wide. It attracts dust from the air, so it must be washed occasionally. Copyright 2008 David Sieg
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Foundations and Floors Permanent foundations should be provided for glass, fiberglass, or the double-layer rigid-plastic sheet materials. The manufacturer should provide plans for the foundation construction. Most home greenhouses require a poured concrete foundation similar to those in residential houses. Quonset greenhouses with pipe frames and a plastic cover use posts driven into the ground. Permanent flooring is not recommended because it may stay wet and slippery from soil mix media. A concrete, gravel, or stone walkway 24 to 36 inches wide can be built for easy access to the plants. The rest of the floor should be covered by several inches of gravel for drainage of excess water. Water also can be sprayed on the gravel to produce humidity in the greenhouse. Environmental Systems Greenhouses provide a shelter in which a suitable environment is maintained for plants. Solar energy from the sun provides sunlight and some heat, but you must provide a system to regulate the environment in your greenhouse. This is done by using heaters, fans, thermostats, and other equipment. Heating The heating requirements of a greenhouse depend on the desired temperature for the plants grown, the location and construction of the greenhouse, and the total outside exposed area of the structure. As much as 25 percent of the daily heat requirement may come from the sun, but a lightly insulated greenhouse structure will need a great deal of heat on a cold winter night. The heating system must be adequate to maintain the desired day or night temperature. Usually the home heating system is not adequate to heat an adjacent greenhouse. A 220-volt circuit electric heater, however, is clean, efficient, and works well. Small gas or oil heaters designed to be installed through a masonry wall also work well. Solar-heater greenhouses were popular briefly during the energy crisis, but they did not prove to be economical to use. Separate solar collection and storage systems are large and require much space. However, greenhouse owners can experiment with heat-collecting methods to reduce fossil-fuel consumption. One method is to paint containers black to attract heat, and fill them with water to retain it. However, because the greenhouse air temperature must be kept at plantgrowing temperatures, the greenhouse itself is not a good solar-heat collector. Heating systems can be fueled by electricity, gas, oil, or wood. The heat can be distributed by forced hot air, radiant heat, hot water, or steam. The choice of a heating system and fuel depends on what is locally available, the production requirements of the plants, cost, and individual choice. For safety purposes, and to prevent harmful gases from contacting plants, all gas, oil, and woodburning systems must be properly vented to the outside. Use fresh-air vents to supply oxygen for burners for complete combustion. Safety controls, such as safety pilots and a gas shutoff switch, should be used as required. Portable kerosene heaters used in homes are risky because some plants are sensitive to gases formed when the fuel is burned. Copyright 2008 David Sieg
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Calculating heating system capacity. Heating systems are rated in British thermal units (Btu) per hour (h). The Btu capacity of the heating system, Q, can be estimated easily using three factors: 1. A is the total exposed (outside) area of the greenhouse sides, ends, and roof in square feet (ft2). On a Quonset, the sides and roof are one unit; measure the length of the curved rafter (ground to ground) and multiply by the length of the house. The curves end area is 2 (ends) X 2/3 X height X width. Add the sum of the first calculation with that of the second. 2. u is the heat loss factor that quantifies the rate at which heat energy flows out of the greenhouse. For example, a single cover of plastic or glass has a value of 1.2 Btu/h x ft2 x oF (heat loss in Btu's her hour per each square foot of area per degree in Fahrenheit); a double-layer cover has a value of 0.8 Btu/h x ft2 x oF. The values allow for some air infiltration but are based on the assumption that the greenhouse is fairly airtight. 3. (Ti-To) is the maximum temperature difference between the lowest outside temperature (To) in your region and the temperature to be maintained in the greenhouse (Ti). For example, the maximum difference will usually occur in the early morning with the occurrence of a 0oF to 5oF outside temperature while a 60oF inside temperature is maintained. Plan for a temperature differential of 60 to 65oF. The following equation summarizes this description: Q = A x u x (Ti-To). Example. If a rigid-frame or post and rafter freestanding greenhouse 16 feet wide by 24 feet long, 12 feet high at the ridge, with 6 feet sidewalls, is covered with single-layer glass from the ground to the ridge, what size gas heater would be needed to maintain 60oF on the coldest winter night (0oF)? Calculate the total outside area (Figure 4): two long sides
2 x 6 ft x 24 ft = 288 ft2
two ends
2 x 6ft x 16 ft = 192 ft2
roof
2 x 10 ft x 24ft = 480 ft2
gable ends
2 x 6 ft x 8 ft = 96 ft2 A = 1,056 ft2
Select the proper heat loss factor, u = 1.2 Btu/h x ft2 x oF. The temperature differential is 60oF - 0oF = 60 oF. Q = 1,056 x 1.2 x 60 = 76,032 Btu/h (furnace output). Although this is a relatively small greenhouse, the furnace output is equivalent to that in a small residence such as a townhouse. The actual furnace rated capacity takes into account the efficiency of the furnace and is called the furnace input fuel rating.
Copy-
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This discussion is a bit technical, but these factors must be considered when choosing a greenhouse. Note the effect of each value on the outcome. When different materials are used in the construction of the walls or roof, heat loss must be calculated for each. For electrical heating, covert Btu/h to kilowatts by dividing Btu/h by 3,413. If a wood, gas, or oil burner is located in the greenhouse, a fresh-air inlet is recommended to maintain an oxygen supply to the burner. Place a piece of plastic pipe through the outside cover to ensure that oxygen gets to the burner combustion air intake. The inlet pipe should be the diameter of the flue pipe. This ensures adequate air for combustion in an airtight greenhouse. Unvented heaters (no chimney) using propane gas or kerosene are not recommended. Air Circulation Installing circulating fans in your greenhouse is a good investment. During the winter when the greenhouse is heated, you need to maintain air circulation so that temperatures remain uniform throughout the greenhouse. Without air-mixing fans, the warm air rises to the top and cool air settles around the plants on the floor. Small fans with a cubic-foot-per-minute (ft3/min) air-moving capacity equal to one quarter of the air volume of the greenhouse are sufficient. For small greenhouses (less than 60 feet long), place the fans in diagonally opposite corners but out from the ends and sides. The goal is to develop a circular (oval) pattern of air movement. Operate the fans continuously during the winter. Turn these fans off during the summer when the greenhouse will need to be ventilated. The fan in a forced-air heating system can sometimes be used to provide continuous air circulation. The fan must be wired to an on/off switch so it can run continuously, separate from the thermostatically controlled burner.
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Ventilation Ventilation is the exchange of inside air for outside air to control temperature, remove moisture, or replenish carbon dioxide (CO2). Several ventilation systems can be used. Be careful when mixing parts of two systems. Natural ventilation uses roof vents on the ridge line with side inlet vents (louvers). Warm air rises on convective currents to escape through the top, drawing cool air in through the sides. Mechanical ventilation uses an exhaust fan to move air out one end of the greenhouse while outside air enters the other end through motorized inlet louvers. Exhaust fans should be sized to exchange the total volume of air in the greenhouse each minute. The total volume of air in a medium to large greenhouse can be estimated by multiplying the floor area times 8.0 (the average height of a greenhouse). A small greenhouse (less than 5,000 ft3 in air volume) should have an exhaust-fan capacity estimated by multiplying the floor area by 12. The capacity of the exhaust fan should be selected at one-eighth of an inch static water pressure. The static pressure rating accounts for air resistance through the louvers, fans, and greenhouse and is usually shown in the fan selection chart. Ventilation requirements vary with the weather and season. One must decide how much the greenhouse will be used. In summer, 1 to 1½ air volume changes per minute are needed. Small greenhouses need the larger amount. In winter, 20 to 30 percent of one air volume exchange per minute is sufficient for mixing in cool air without chilling the plants. One single-speed fan cannot meet this criteria. Two single-speed fans are better. A combination of a single-speed fan and a two-speed fan allows three ventilation rates that best satisfy year round needs. A single-stage and a two-stage thermostat are needed to control the operation. A two-speed motor on low speed delivers about 70 percent of its full capacity. If the two fans have the same capacity rating, then the low-speed fan supplies about 35 percent of the combined total. This rate of ventilation is reasonable for the winter. In spring, the fan operates on high speed. In summer, both fans operate on high speed. Refer to the earlier example of a small greenhouse. A 16-foot wide by 24-foot long house would need an estimated ft3 per minute (cubic feet per minute; CFM) total capacity; that is, 16x24x12 ft3 per minute. For use all year, select two fans to deliver 2,300 ft3 per minute each, one fan to have two speeds so that the high speed is 2,300 ft3 per minute. Adding the second fan, the third ventilation rate is the sum of both fans on high speed, or 4,600 ft3 per minute. Some glass greenhouses are sold with a manual ridge vent, even when a mechanical system is specified. The manual system can be a backup system, but it does not take the place of a motorized louver. Do not take shortcuts in developing an automatic control system.
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Watering Systems A water supply is essential. Hand watering is acceptable for most greenhouse crops if someone is available when the task needs to be done; however, many hobbyists work away from home during the day. A variety of automatic watering systems is available to help to do the task over short periods of time. Bear in mind, the small greenhouse is likely to have a variety of plant materials, containers, and soil mixes that need different amounts of water. Time clocks or mechanical evaporation sensors can be used to control automatic watering systems. Mist sprays can be used to create humidity or to moisten seedlings. Watering kits can be obtained to water plants in flats, benches, or pots. CO2 and Light Carbon dioxide (CO2) and light are essential for plant growth. As the sun rises in the morning to provide light, the plants begin to produce food energy (photosynthesis). The level of CO2 drops in the greenhouse as it is used by the plants. Ventilation replenishes the CO2 in the greenhouse. Because CO2 and light complement each other, electric lighting combined with CO2 injection are used to increase yields of vegetable and flowering crops. Bottled CO2, dry ice, and combustion of sulfur-free fuels can be used as CO2 sources. Commercial greenhouses use such methods. Alternative Growing Structures A greenhouse is not always needed for growing plants. Plants can be germinated in one's home in a warm place under fluorescent lamps. The lamps must be close together and not far above the plants. A cold frame or hotbed can be used outdoors to continue the growth of young seedlings until the weather allows planting in a garden. A hotbed is similar to the cold frame, but it has a source of heat to maintain proper temperatures.
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Building a Home-Grown Photobioreactor
Section IV Making A Batch Process Photobioreactor
At Home
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Photo-bioreactors Algae can also be grown in a photo bioreactor. A photo bioreactor (PBR) is a bioreactor which incorporates some type of light source. Virtually any translucent container could be called a photo bioreactor, however the term is more commonly used to define a closed system, as opposed to an open tank or pond. Enclosed PBRs have the following advantages over open pond production. 1. Better control of algal culture 2. Larger surface-to-volume ratio 3. Better control of gas transfer 4. Reduction in evaporation of growth medium 5. More uniform temperature 6. Better protection from outside contamination 7. Higher algal cell densities are possible. Covering open ponds does alleviate some of the disadvantages, but enclosed systems will still provide better control of temperature, light intensity, better control of gas transfer, and larger surface area-to-volume ratio. An enclosed PBR design will enhance algal biomass production by keeping algae genetics pure and reducing the possibility of parasite contamination. Photo bioreactors take care of many of the problems associated with an open system. It allows more species to be grown, it allows the species that are being grown to stay dominant, and it extends the growing season, only slightly if unheated, and if heated it can produce year round. Because these systems are closed, all essential nutrients must be introduced into the system to allow algae to grow and be cultivated. Essential nutrients include carbon dioxide, nitrates, water, minerals and light. A pond covered with a greenhouse could be considered a photo bioreactor. A photo bioreactor can be operated in "batch mode" but it is also possible to introduce a continuous stream of sterilized water containing nutrients, air, and carbon dioxide. As the algae grows, excess culture overflows and is harvested. If sufficient care is not taken, continuous bioreactors often collapse very quickly, however once they are successfully started, they can continue operating for long periods. An advantage of this type of algae culture is that algae in the "lag phase" is produced which is generally of higher nutrient content than old "senescent" algae. It can be shown that the maximum productivity for a bioreactor occurs when the "exchange rate" (time to exchange one volume of liquid) is equal to the "doubling time" (in mass or volume) of the algae.
Making Algae Biodiesel at home
Different types of photo bioreactors include: •
Tanks provided with a light source
•
Polyethylene sleeves or bags
•
Glass or plastic tubes
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Limitations This system isn’t perfect by any means. There are always problems and flaws in any design. The first goal is to get a workable system that will grow algae. After that you can perfect the design based on your own criteria. But we used this design in the initial stages, and worked through any issues as we went. You’ll have to do the same. Sorry there are no illustrations of a “perfect” unit. Limitations: • • •
Because it’s a “batch” system you’ll be constrained by the size of the unit itself. You make a batch, empty it, make another batch. Rinse and repeat. This is a serious consideration. This is why the early stages of estimating yield and growing cultures in a step by step basis, gradually increasing the size of the tank is so important. This design isn’t perfect. It was where we started, not where we ended.
Design Issues: •
This is an early design and it contained some issues we had to work around. Mainly an outtake device for the algae. • This was solved by using “trap” on the bottom of each tube. • •
You’ll also want to build it higher than shown here to drain the algae into a bucket. You can keep the liquid and reuse it.
Another idea we used was a “hair trap” (pictured left)
Also sometimes algae will clog the tubes. We ended up getting around this as well using threaded PVC cap. You can use a cap at the top and bottom ideally, or just the bottom.
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Building a “Down and Dirty” Photo bioreactor
An extremely simple design. We’re not talking a lot of bells and whistles here. It will however, get you going in the right direction. From there, you’ll need to branch out on your own, dealing with your own climate, your own strains and the problems associated with growing them. The nice aspect of this PBR is that it is completely scalable. By that I mean, you can take same basic idea and build it to whatever size you want. I’ve seen some pictures of this same basic design used in massive commercial PBR’s. The cost: $200-$400 Tools needed: • • • • • • • •
Circular saw Screwdriver Razor Pliers Dremal Tool Wire cutters Hole saw Acrylic cement
Materials: •
8 –1”x 6” x 8’ pine boards Available at any lumber store or home improvement outlet.
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Acrylic Sheets: 1/2” x 4’ Available at any hardware of home supply store.
Acrylic and/or any clear Tubing: 3 3/4” OD 1/4” ID: There are two types of acrylic, • • •
Cast and Extruded. Use the cast acrylic tube for this PBR. Extruded acrylic will eventually crack under the pressure of the water in the tubes and you will kill an entire algae colony Fertilizer Chemicals: To help keep algae healthy we use both de-chlorinator and a phyto-grow algae fertilizer. The fertilizer is a good place to start and makes the algae some kind of nutrients. You’ll need to experiment here with your own nutrients. •
•
Get these at any aquarium store.
A Hole saw: • •
3-1/2” OD , 3-1/4” ID hole saw found at any tool of home Improvement store. Be careful when using these. Sometimes the saw will stuck in the acrylic.
get
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Aquarium airline tubing: You’re going to need (3) 20 foot packages. • Look for runs without any kinks in the tubing itself. You can find these at any fish/aquarium store.
WISA Air Pump: Find ones that have both an input and output that you can capture the air and pass it along. • You can also set these up in tandem and run them from solar panels. You’ll need one air pump for every tube.
so
Basic Dry Wall Screws: Buy a box. They’re cheap and will hold much better than other screws against any vibration.
Air Valves: You’ll need 2 of them. You get them anywhere. You can use them to mix and re-cycle the air through the reactor with very good control.
Live Algae cultures: Either buy the specific strain you want, and see if it will adapt, or even cheaper, get some local cultures from your own environment.
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Assembly
What you’re going to do…
1. Cut the pine boards to the following lengths: • 2– Six foot lengths • 2 - Seven foot lengths • 2– Two foot lengths • 2– One foot lengths 2. Cut the bottoms of the 6 foot and the 1 foot boards, cut a 15-30 degree cut so that the stand can angle better for light exposure. •
Choose the correct angle by standing where you want the position the photo bioreactor and observing the way the light moves carefully across the area it’s going to sit.
3. Lay the 7 foot lengths flat, and space out the 3 3/4” inch holes with one inch gaps between them. • •
Leave 6 inches on each end for air-flow. You can also create a cardboard pattern easily and use this to get consistent holes. Note: You can screw the boards together and cut both at the same time, making each cut perfect fit to the one below it. 4. Screw the frame together with the cut 7 foot lengths forming the top and bottom. •
Use the 6 foot lengths as the frame sides.
5.) Cut the tubing into 6 foot pieces.
•
•
• Then using the acrylic sheets and the hole saw, cut out round circular pieces out of the sheet. • Take some acrylic cement, applying it around the edges, Once the glue has dried diagonally drill a 1/8th" hole through the cap and through the side of the tube staying in the cap end the whole time. Fill the hole with thick CA hobby glue and using a 2 1/2" long drywall screw, screw through the cap end and into the wood frame to anchor the tube to the frame. This adds structural strength to the frame as well.
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6. In between each of the tubes mount one of the pumps to the top of the frame. •
You could also mount the pumps on the bottom instead
Note: That the protective caps are still on the pumps. Keep them there until your ready to put liquid in them.
7. At the right end of the reactors frame, hot glue one of the valves to the frame. •
It can be modified slightly with a plug so that it no longer passed through but required the valve to be open.
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A diagram of the air hoses. Note: You can choose to recycle a portion of the air by adjusting the outlet valve and using the recirculation valve on the right. 8. Now, start getting the plumbing hooked up. •
•
Have the air from the last tube in the system plugging into the common line on the valve. The knob on the left is the recirculation valve. On the right is the exit valve that just vents to the atmosphere. 9. Every other tube we will connect to the input on a pump to boost the air pressure along the array of tubes. •
The seal from the second tubes outlet to the next pumps input should be air tight as there is no booster pump between every other tube . • You want the pressure to do the work for you. •
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10. Here is the input valve. • • •
The valve on the right is the recirculation back pressure valve. The knob on the left is the input line to the first pump. The stem on the right is the input to the system from your CO2 supply.
Here is an illustration of the back of the rack. The line running from left to right is the recirculation line. You can see here the outflow lines being hooked up now. • Use a few spots of hot glue to hold the lines down well. •
Illustration of air lines between the tubes.
11. Here is how the electrical should look when completed. Just wire these up in parallel using your 12V power source. • At this point you can test the pumps. • These pumps operate at a fairly high speed and together they do nicely. • There was a more noise than I expected • Once the tubes are full of water they create less noise. •
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12. Two things going on here. We decided we needed to distribute the weight differently. You can see the air lines running between the tubes down to the bottoms of each tube. •
13. Close up of the frame modification, (from back) • Basically some glue to attach the two 2 foot boards to the frame as well as to the tubes themselves. • The reasoning here is to help take the load off the bottom of the frame and the ”I “shape will distribute the load more evenly. Front view of the frame with the glue applied and drying. All we have left to do is the bottom plumbing.
14. We left the lines running down a little long for a reason. The goal is to be water tight. •
•
Insert the line into the hole from the hole saw and loop it once in that extra 1/2 inch gap we left. Using silicone, fill the half inch gap and imbed the hose in it.
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15. An illustration of the bottom once that is done. In reality some of the glue may seep up inside the tube and not make a perfect seal. • Be on the look out for this now rather than later. •
This is what the finished photo-bioreactor should look like.
16. Find a sunny place that you want to
put the reactor at. A place that gets a lot of noon/late afternoon sun. • If nowhere is sunny enough of a spot add some Mylar or aluminum foil to the back of the frame to reflect light back towards the reactor. •
17. The filling process is very straight forward. • • • •
Drill a second hole in the tops of the tubes to let the air escape as you fill it up. It makes filling a lot faster. You need to plug them up air tight as well. Use some small rubber stoppers I picked up at the local home center.
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97 18. Reactors final hookups complete. I chose to run a line from the vent from our furnace and water heater up on the roof to the reactor. The power for our reactor is from a harbor freight 45 watt solar panel kit. The kit includes everything you need excluding a battery. But that was fine because when it’s dark it doesn’t really matter if it’s not bubbling away. Once again I really was surprised at the amount of air those pumps put out.
19. So before I called it a night it was time to inoculate the tubes. Using that second hole I drilled in the top cap I added the dechlorinator as per the instructions. The little syringes really help in adding the stuff through the little 1/4" holes. Next we added the plankton and fertilizer per its instructions. The microalgae was 12 oz so we put 1 oz in each tank. You really couldn’t see it at all in the water. But in a few days the water starts to green up.
Day 2. No visible change to the reactor. Note that I had to add an inch of water to the first tank due to evaporation. On hotter days I think that may be a problem, but nothing a nice slow drip system couldn’t fix. From a rain water recycling system of course.
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Day 3: Finished PBR up and running. Algae greening the PBR
Final Thoughts: Why not go vertical with the tubes and build greenhouse around them so that you can get 365 degrees of sunlight? This looks like a great idea and I wish I would have thought of it. As always, the experimentation is endless.
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Section V Harvesting and Oil Extraction
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Harvesting Algae at Home: The major factors to consider when harvesting algae at home is • cost and • ease of harvesting. So how do you harvest algae on a small scale? One simple and cheap method, is simply to harvest 1/2 of the total amount of algae, leaving the other half behind to continue growing. This method is not perfect, nor is it efficient. What it is, is cost-efficient. What you would do in this instance is use a fine mesh net, like a pool net, to skim the algae off the surface. If you’re lucky enough to live in an area where labor is cheap, or have lots of children, or students (LOL) this is indeed a cost-effective method of harvesting algae. As of now, I know of no other method to harvest algae that meets these to criteria. After harvesting by hand, you’ll have to spend money. Another method, using certain strains (Botryococcus braunii) grow on the bottom, when it is ready to harvest, the oil content force the algae to the surface or the top , then scoop it off. When high lipid algal strains are perfected, and sold commercially, I’m sure this will be the most common method of harvesting, outside of a photobioreactor. At the present time, however, we’re not left with much else. Once the algae has been harvested, spread it out on a thin wire/plastic mesh screen and allow to dry in the sunlight until completely dry. These screens can be built for this purpose easily, or junk window screens can be used. This doesn’t need to be elaborate. Simply build any kind of square frame, stretch the mesh across it, and staple it down. Be sure to add extra framing material to the middle or anywhere there is sagging. For extra strength, lay more framing material OVER the mesh, and screw it down. Think a large window screen, and you’ll get the idea. For a more in-depth treatment of all methods available, keep reading...
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Harvesting Algae Algal harvesting is one of the major factors that must be overcome in order for algae to be used as a fuel source. The problem is that microalgae mass cultures are dilute, typically less than 500 mg/l on a dry weight organic basis, and the cells are very small. Many one celled species are around 5 micrometers in diameter. In order to be processed into biodiesel the algae must be in the form of a paste that is 15% solids. In the raceway ponds the mixture is about 1% solids, this mixture must go through a process which will result in a concentration of at least 15%. Many different algae harvesting processes have been studied. Dr. John Benemann in 1996. shows a number of these processes. Centrifugation – The algae pond solution is pumped into a large centrifuge, which rotates at several thousand RPM causing the algae to be pressed against the outer wall, which is a filter only a few microns in spacing. The water is forced out, while the algae remain of the screen in the form of a paste about 20% algae. This is a proven method that has been extensively used when working with microalgae. Studies have determined that a nozzle disc type centrifuge with intermittent discharge is the best option for algae harvesting (Mohn, 1988). The downfall however is the high power requirements or high cost associated with operating the centrifuge. For most home producers, the cost of the centrifuge makes this method prohibitive. Chemical flocculation – Certain chemicals like lime, alum, or chitosan can be added to the algae pond solution causing charge neutralization of the algae. This results in the algae clumping together. There is also a very high cost associated with this method, because of the large amounts of chemicals that are required. The APM uses settling ponds as the initial harvesting method, which will bring the solution to 3% algae. From the settling ponds this mixture will be put through a centrifuge which will bring the mixture to 15% algae. Using the settling ponds will help to reduce energy consumption and cost of centrifuge operations. These, of course, are mass production methods and unlikely to be encountered at home. However, as you start to scale up understanding these processes are necessary. One of the problems holding back mass production of algae for biodiesel is an efficient, cost-effective, harvesting technique. Ultrasound based methods of algae harvesting are currently under development, and other, additional methods are currently being developed. However, for the home grower, most of the methods are cost prohibitive.
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Froth flotation is another method to harvest algae whereby the water and algae are aerated into a froth, with the algae then removed from the water. Alum and ferric chloride are chemical flocculants used to harvest algae. A commercial product called "Chitosin", commonly used for water purification, can also be used as a flocculant. The shells of crustaceans are ground into powder and processed to acquire chitin, a polysaccharide found in the shells, from which chitosin is derived. Water that is more brackish, or saline requires additional chemical flocculant to induce flocculation. Harvesting by chemical flocculation is a method that is often too expensive for large operations. Interrupting the carbon dioxide supply to an algal system can cause algae to flocculate on its own, which is called "autoflocculation".
Copyright 2008 David Sieg
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103 Oil Extraction
For the purpose of home oil extraction, there really are only 2 viable methods. Unfortunately, one of the methods is so dangerous, I won’t go into detail. The simplest method is mechanical crushing. (Oil expeller) Since different strains of algae vary widely in their physical attributes, various press configurations (screw, expeller, piston, etc) work better for specific algae types. Often, mechanical crushing is used in conjunction with chemicals (see below). •
Expression/Expeller press: When algae is dried it retains its oil content, which then can be "pressed" out with an oil press. Many commercial manufacturers of vegetable oil use a combination of mechanical pressing and chemical solvents in extracting oil. This is really the only viable method for the home producer at this time.
•
Chemical solvents: Hexane and Benzene and ether have been used, The downside to using solvents for oil extraction are the dangers involved in working with the chemicals. Care must be taken to avoid exposure to vapors and direct contact with the skin, either of which can cause serious damage. Benzene is classified as a cancer causing carcinogen. Chemical solvents also present the problem of being an explosion hazard. The truth is, this method is so dangerous to your health, I won’t even examine it here.
Other more large scale and/or commercial methods: •
Soxhlet extraction is an extraction method that uses chemical solvents. Algal oils are extracted through repeated washing, with an organic solvent such as hexane or petroleum ether.
•
Enzymatic extraction: Enzymatic extraction uses enzymes to weaken the cell walls with water acting as the solvent, this makes fractionation of the oil much easier. The costs of this extraction process are estimated to be much greater than hexane extraction. The enzymatic extraction can be supported by ultrasonication. The combination "sonoenzymatic treatment" causes faster extraction and higher oil yields.
•
Osmotic shock: Osmotic shock is a sudden reduction in osmotic pressure, this can cause cells in a solution to rupture. Osmotic shock is sometimes used to release cellular components, such as oil.
•
Supercritical fluid: In supercritical fluid/CO2 extraction, CO2 is liquefied under pressure and heated to the point that it has the properties of both a liquid and a gas, this liquified fluid then acts as the solvent in extracting the oil.
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Ultrasonic-assisted extraction: Ultrasonic extraction, a branch of sonochemistry, can greatly accelerate extraction processes. Using an ultrasonic reactor, ultrasonic waves are used to create cavitation bubbles in a solvent material, when these bubbles collapse near the cell walls, it creates shock waves and liquid jets that causes those cells walls to break and release their contents into the solvent.
Other methods are still being developed, including ones to extract specific types of oils, such as those with a high production of long-chain highly unsaturated fatty acids.
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A Homemade Oil Extraction Press Oil has been extracted from plant material for centuries. From olive oil in Europe to palm oil in Asia. This methods in this book deals with extraction by pressure. Pressure extraction separates the oil from the solid particles by simply squeezing the oil out of the crushed mass of algae. The simplest method is pressed out mechanically. The simplest way is by placing heavy rocks on the materials. Or bags of algal pulp, rocks, anything which has weight, can be placed one above another in a box or cylinder, and great pressure can be slowly brought to bear on the whole mass. A long lever such as the one shown in Figure 1 can exert up to 100 pounds per square inch.
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Since greater pressure provides greater oil recovery, the lever has often been replaced by heavy and strong mechanical jacks of several designs (screw jacks, ratchet jacks, and hydraulic jacks). A 20-ton jack can exert 1,000 pounds per square inch on a small square of algal paste. BATCH PRESSES A batch press is a press that processes one batch of algal oil at a time. Batch presses range from small, hand-driven presses that an individual can build to power-driven commercial press capable of processing many tons of algae a day. Small Batch Presses Small batch presses are simple, but inefficient. However, they do work. In a home environment, they work pretty well. They can be used in remote areas and can help determine whether there is a market for oil produced locally. Few resources are needed for an operation on this scale: lumber, basic tools and hand labor for pressing. Much hand labor is required to produce a small amount of oil this way. Advantages of small batch presses: o o o o o
They can be made of locally available materials. They can produce a good quality product. They are easy to repair. Their cost is low. They do not require trained operators.
Disadvantages of small batch presses: o They are labor intensive. o Complete recovery of the oil from the algae is difficult.
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Building a Home Made Algae Press The following press is based upon an open source apple press design. However the exact same design can be used to press algal oil with very few modifications. Compression and/or pressure needs to be more, and don’t expect the flow of oil you see here. However, this will work for most home algae producers. The below measurements are in centimeters.
Materials Needed Wood: 6 -750 x 100 x 50 (96 x 46 finished size) - main frame members 2 - 350 x 100 x 50 (96 x 46 finished size) - end pieces for stability 1- 480 x 46 x 46 - tongue for juice tray 4 -540 x 100 x 18 (or 15) - lip for juice tray Iron: 150mm / 6" M10 Plated Coach Bolts - 8 off 100mm / 4" M10 Plated Coach Screws - 4 off Worktop offcut: 1 -500 x 500 x 38 - press base / pressure plate / juice tray base (Optional, but helps) 2 ton hydraulic Jack: You may pick up a decent hydraulic jack from a flea market or garage sale, if all else fails, check the truck on your car. Odds and Ends: Various pins, a few brass screws, waterproof PVA and some polyurethane varnish. A basic selection of hand tools such as a good tenon saw, try-square, drill and bits, G-cramps / vice / work bench, small plane (smoothing or block), some glass paper to finish off.
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The frame is made from planed untreated 2" x 4" (94mm x 44mm ) If you’re using a car jack the top supports needs to be beefed up and strengthened as much as possible. The top two members can be removed and replaced with laminated Birch multi-ply. This is much stronger and less likely to twist or bend than normal softwood .
Detail close-up of the lower frame: The whole thing is secured with a mix of bolts and screws. Simple pre-drill and put it together. You can also run a router over the frame soften the edges and reduce snags on the netting. Sandpaper can also be used and works just as well.
If you want the press to be at more workable height, mount it on a workbench, and clamp it down, which holds it very firmly and keeps everything stable.
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Detail Illustration of slide fit: It's a very close fit and you should slide the press in to clear the tails of the bolts.
The tray is simply a waste cut of 3/4” (38mm) kitchen countertop - most home improvement stores have piles of offcuts; It's lipped in sealed and varnished 5/8” (15mm ) softwood, the piece of softwood underneath is a tongue in grooved into the lower frame The oil outlet pipe is a waste piece of white plastic WC overflow pipe located at the top.
The oil tray should be a very tight fit both between the vertical members and between lower frame members. It settles under the pressure of the press and it usually takes a banging or two to remove the tray from between the frame.
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To press algal oil, put the dried algae into “cheesecloth” sacks, pile them on one another. Add short pieces of 2x4 across the top to distribute the pressure evenly.
The form (height x width) is produced by using a 'mold' which is laid onto a couple of thin softwood laths resting on the algal bags below. You can use mosquito net curtain or cheese cloths (nylon or polyester) and select by the thickness and strength of the mesh .
Dry or semi dry Algae is poured into the mold and spread evenly to give the desired depth. The net curtain rectangle is then folded over to produce a rectangular bag, the slats are slid out, frame lifted off and the process is repeated.
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The oil won’t start to flow straight away so you’ll probably have to add more blocks of timber that spread the force of the screw. Just keep cranking it down.
Distributing the pressure evenly should increase the flow of oil and give a more efficient pressing. Oil from algae however won’t flow at this rate. The practice is exactly the same however.
Keep adding more 2 x4’s as needed to take up the gap if you’ve run out of screw thread. By putting the timber at right angles and using block board, you can ensure the pressure is fairly equally distributed. The pressure is really on here and the algae have compressed considerably. In order to extract the oil, it is necessary to burst the cell walls. You will need a lot of pressure to do this.
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Using a Hydraulic Car Jack Another variation in this design is to beef up the top headers with composite plywood on each side, then add a steel plate for a hydraulic car jack to fit into. Note: This adds to the downward pressure Considerably but also the UPWARD pressure being exerted as well. The top brace needs to be very strong.
Final considerations The wet plant tissue is placed in the press in layers, with each layer separated from the next by a press cloth. Pressure is applied, slowly at first, and then increased as the oil content in the tissue decreases. Maximum total pressure is 2,000 pounds per square inch for one inch layers. Total time to load the press, apply the pressure, and remove the cake, is approximately one hour. Drainage of the oil while under pressure may require 30 to 45 minutes. The amount of raw material that can be handled depends on the size of the press, which in turn depends on whether it is a hand press or is operated by electrical power and/or hydraulic power..
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Creating a Oil Press from a Hydraulic Jack in Your Car. Hydraulic presses, which are suitable only for batch processing, may be powered either by hand or by electricity. In many parts of the world, they are the most practical and economical way to extract oil from algae. A hydraulic press is simple in operation. Use an ordinary car jack. These are simple designs and pretty much self-explanatory.
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Another option, is using the simple hydraulic press on the preceding page with this open source design. In this situation, you’re getting the best of both worlds. You’ll have to improvise, but it’s do-able. The downside is that it will only press a small amount of algae at a time.
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The cylinder and piston of the hydraulic jack are removed as a unit, and a piece of round bar stock of the same diameter and length as the cylinder is substituted. A hole is drilled through it lengthwise for the passage of fluid, and the ends are threaded, one end to screw into the base of the jack housing, the other to take a nut and pipe reducer into which the feed pipe is to be fitted. After the bar is screwed into the housing, a washer is placed over it and the nut turned down tightly to prevent loss of fluid. It may be necessary to put a gasket under the washer as a seal. Instead of using a reducer, the feed pipe can be threaded and fitted into a counterbored, tapped hole in the bar. Next, make a housing for the cylinder and piston. This is made from a length of 1¾-in. iron pipe about half as long as the cylinder, welded to a metal base which is threaded like the jack housing to receive the cylinder, and is drilled for the passage of fluid. A nut is welded to the base and a feed-pipe coupling screwed into it. The cylinder and piston in the substitute housing are mounted on the frame as shown in the upper detail of Fig. 2, with the Copy-
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116 end of the housing resting on the angle iron an the cylinder shoulder butting up against the underside of the angle iron. The housing is clamped securely between the retaining blocks. In this position, the piston will press down on the work when fluid is pumped into the cylinder. The feed pipe is attached by couplings and elbows, and the jack is supported by a brace at the side of the frame. Coil springs, attached to the frame spacers by eye bolts, pull up the piston and force the fluid back when the valve is released.
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CHOOSING YOUR METHOD The type of press that is appropriate depends largely on the size of the operation. Oil processing operations range in size from cottage industries processing only a few pounds of algal cake per day, to factories processing as much as 3 or 4 thousand tons of algae per day. For small operations (processing less than 1 ton of dry algae per day) , the right equipment is almost always a form of batch press. If 1 or more tons per day are to be pressed, the right equipment is most often an expeller. III. SEQUENCE OF OPERATIONS The sequence of operations in processing oil for pressing is as follows: STORAGE The plant tissue containing the oil must be properly stored and prepared for extraction, to maintain high quality in the final product. If the oil-bearing material is dry, it must be stored so that it remains dry, for optimum extraction and quality of the oil. If the oil-bearing material is wet plant tissue, it should be processed for oil-extraction as soon as possible after harvest so that storage time is kept to a minimum. Oils in the presence of water deteriorate rapidly, forming free fatty acids. CLEANING After the oil-bearing materials have been removed from storage, the first step in preparing them for oil extraction is to clean them. The cleaning is done so that the oil is not contaminated with foreign materials, and so that the extraction process can proceed as efficiently as possible. Inspect the cake carefully and remove stones, sand, dirt, and spoiled seeds. Dry screening is often used to remove all material that is over or under size.
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HEATING The exact reason that heating improves oil extraction is unknown, but it does increase yields. Also, heating is useful if there are enzymes in the plant tissue that have a deteriorating effect on the oil quality. If the oil seed cake (that is, the residue remaining after oil removal by pressing) is to be used for feed or food, heating may be useful in increasing protein availability. Sometimes oil-bearing material is pressed without being heated. Oil extracted in this way is called cold press oil. PRESSING The materials prepared in these ways are pressed, usually in a lever press, hydraulic press, or expeller, to remove the oil. CLEANING It is important to use clean equipment, so wash all the utensils well at the end of the day. Also, allow no copper in the operation. Copper and certain other heavy metals cause undesirable changes in oils. Even a copper bolt in a press can damage the output of your product. Use cast iron, or stainless steel, but no copper or copper-bearing materials.
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If you’re interested in larger scale oil processing methods, you’ll most certainly need industrial machinery. Below is a small list that will get you going in the right direction. EQUIPMENT MANUFACTURERS: OIL PROCESSING Anderson International Corporation 19699 Progress Drive Strongsville, Ohio 44136, USA Crown Iron Works P.O. Box 1364 Minneapolis, Minnesotta 55440, USA CeCoCo P.O. Box 8, Ibaraki City Osaka Pref. 567, JAPAN French Oil Millers P.O. Box 920 Piqua, Ohio 45356, USA Hander Oil Machinery Corporation Osaka, JAPAN S.P. Engineering Corporation P.O. Box 218, 79/7 Latouche Road Kampur, INDIA Stork Company Apparatenfabriek, N.V. Roorstraat Post-Bon 3007 Amsterdam, HOLLAND Rose, Downs and Thompson, Ltd. Old Foundry HU11, ENGLAND Officine Meccaniche Angelo e Tullio Bosello VIllatera de Saonara Padova, ITALY Mathias Reinartz Maschinewfabril P.O. Box 137, Industriestrasse 14 404 Neuss, WEST GERMANY IBG Monforts and Reiners, P.O. Box 516 4050 Monchengladbach 2, WEST GERMANY
Copyright 2008 David Sieg
Making Algae Biodiesel at home ORGANIZATIONS INVOLVED WITH OIL PROCESSING CANOLA 301433 Main Street Winnipeg, Manitoba CANADA R3B 1B3 Cotton Development Board P.O. Box 371 Tamale, GHANA International Centre for Agricultural Research P.O. Box 5466 Alleppo, SYRIA Khadi Village Industries Commission Irla Road Vileparle, Bombay 56, INDIA Makeni Ecumenical Centre Box RW 255 Lusaka, ZAMBIA Malkerns Research Station P.O. Box 4 Malkerns, SWAZ ILAND National Cottonseed Products Association P.O. Box 12023 Memphis, Tennessee 38112, USA National Horticultural Research Station P.O. Box 220 Thika, KENYA Nigerian Institute for Oil Palm Research Benin-Lagos Road Benin City Bendel State, NIGERIA Punjab Vegetable Ghee Board 5 Bank Square Lahore, PAKISTAN
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Biodiesel Algae Reading List Pulz,O.
2004 Valuable products from biotechnology of microalgaeShi
Mamatsu,H. 2004 Mass production of Spirulina, an edible microalga Jupsin,H. 2003
Dynamic mathematical model of high rate algal ponds (HRAP)
Kinast, J.A. 2003 Production of Biodiesels from Multiple Feedstocks andProperties of Biodiesels and Biodiesel/Diesel Blends Richmond,A. 2003 Growth characteristics of ultrahigh-density microalgal cultures Suh,I.S. 2003 Photobioreactor engineering: Design and performance (no author) 2002 A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions Lee,Y.K. 2001 Microalgal mass culture systems and methods: Their limitation and potential Borowitzka,M.A. 1999 menters
Commercial production of microalgae: ponds, tanks, tubes and fer-
(no author) 1998 Biodiesel Research Progress 1992–1997 Sheehan, J. J. 1998 An Overview of Biodiesel and Petroleum Diesel Life Cycles Sheehan, J. J. 1998 A Look Back at the U.S. Department of Energy’s Aquatic Species Program: Biodiesel from Algae Benemann,J.R.
1997 CO2 mitigation with microalgae systems
Borowitzka,M.A. 1997 Microalgae for aquaculture: Opportunities and constraints Radmer,R.J. 1996 Algal diversity and commercial algal products Sheehan,J.J.1994 Bioconversion for Production of the Renewable Transportation Fuels in the United-States - a Strategic Perspective Wilde,E.W.1991 Cultivation of Algae and Nutrient Removal in a Waste Heat Utilization Process Harrington,K.J. 1986 Chemical and Physical-Properties of Vegetable Oil Esters and their Effect on Diesel Fuel Performance
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Section VI Large Scale Production Concepts
Copyright 2008 David Sieg
Making Algae Biodiesel at home
Algal Production in Outdoor Ponds Large outdoor ponds either with a natural bottom or lined with cement, polyethylene or PVC sheets have been used for algal production for many years. The nutrient for outdoor cultures is based on that used indoors, on a larger scale of course, but agriculturalgrade fertilizers can be used instead in many situations. However, many fertilizers can be expensive and it sometimes induced a period production peaks followed by total algal crashes. In other words, be careful using them. Natural blooms can be maintained at a reasonable cell density throughout the year and the ponds are flushed with salt water whenever necessary. Culture depths are typically 0.25-1 m. Algal production in outdoor ponds is inexpensive, but is only suitable for a few, fastgrowing species because of problems with contamination by predators, parasites and “weed” species of algae. Also, outdoor pond production is often characterized by a poor consistency and unpredictable culture crashes caused by changes in weather, sunlight or water quality.
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Algal production cost Estimates of the algal production cost range from US$ 4 to 300 per kg dry biomass. (commercially...You should be able to get this down to $1.00 easily using home-grown methods outlined here.) Algal production in outdoor ponds is relatively cheap, but is only suitable for a few, fast -growing species and is characterized by a poor batch-to-batch consistency and unpredictable culture crashes due to contaminations and/or changing climatological conditions.
Mass production on algae Undoubtedly, very high yields can be obtained if sufficient algae are available and an appropriate culture management is followed. Unfortunately in most places it is not possible to cope with the fast filtration capacity of the rotifers which require continuous algal blooms. If the infrastructure and labor is not a limiting factor, a procedure of continuous (daily) harvest and transfer to algal tanks can be considered. In most places, however, pure algae are only given for starting up rotifer cultures or to enrich rotifers Extensive culture techniques (using large tanks of more than 50 m3) as well as intensive methods (using tanks with a volume of 200-2000 l) are applied. In both cases large amounts of cultured microalgae, usually the marine alga Nannochloropsis, are usually inoculated in the tanks together with a starter population containing 50 to 150 rotifers.ml -1 .
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Large Scale Production Concepts When cultivating algae, several factors must be considered, and different algae have different requirements. The water must be in a temperature range that will support the specific algal species being grown. Nutrients must be controlled so algae will not be "starved" and so that nutrients will not be wasted. Light must not be too strong nor too weak. Algae can be cultured in raceway-type ponds and lakes. Because these systems are open to the elements, sometimes called "open-pond" systems, they are much more vulnerable to contamination by other microorganisms, such as invasive algal species or bacteria. Because of these factors, the number of species successfully cultivated in an "open-pond" system for a specific purpose (such as for food, for the production of oil, or for pigments) are relatively limited. In open systems one does not have control over water temperature and lighting conditions. The growing season is largely dependent on location and, aside from tropical areas, is limited to the warmer months. A major benefit to this type of system are that it is one of the cheaper ones to construct, in the very least only a trench or pond needs to be dug. It can also have some of the largest production capacities relative to other systems of comparable size and cost. This type of culture can be viable when the particular algae in question requires (or is able to survive) some sort of extreme condition that other algae can not survive. For instance, Spirulina sp. can grow in water with a high concentration of sodium bicarbonate and Dunaliela salina will grow in extremely salty water. Open culture can also work if there is a simple inexpensive system of selecting out the desired algae for use and to inoculate new ponds with a high starting concentration of the desired algae. Some chain diatoms fall into this category as they can be filtered from a stream of water flowing through an outflow pipe. A "pillow case" of a fine mesh cloth is tied over the outflow pipe and most algae flow right through. The chain diatoms are held in the bag and used to feed shrimp larvae (in Eastern hatcheries) and to inoculate new tanks or ponds.
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A variation on the basic "open-pond" system is to close it off, to cover a pond or pool with a greenhouse. While this usually results in a smaller system, for economic reasons, it does mean a lot of problems associated with the open pod system are eliminated. In most algal-cultivation systems, light only penetrates the top 3-4 inches of the water. This is because as the algae grow and multiply, they become so dense that they block light from reaching deeper into the pond or tank. Algae only need about 1/10th the amount of light they receive from direct sunlight. Direct sunlight is often too strong for algae. In order to have ponds that are deeper than 4 inches algae growers use various methods to agitate the water in their ponds, thus circulating the algae so that it does not remain on the surface, which would cause it to be over-exposed. Paddle wheels can be used to circulate the water in a pond. Compressed air can be introduced into the bottom of a pond or tank to agitate the water, bringing algae from the lower levels up with it as it makes its way to the surface. Apart from agitation, another means of supplying light to algae is to place the light in the system. Glow plates are sheets of plastic or glass that can be submerged into a tank, providing light directly to the algae at the right concentration. In other words, you can place grow lights on the bottom of the pond to shine light upward. This is a neat rick and it works pretty well. However, like everything else, experimentation is necessary to adjust the right amount of light. The odor associated with bogs, swamps, or any stagnant waters that have been taken over by algae, is due to oxygen depletion in the water caused by the decay of deceased algal blooms. Under anoxic conditions, the bacteria inhabiting algae cultures break down the organic material and produce hydrogen sulphide and ammonia which causes the odor. This condition, called hypoxia, often results in the death of all aquatic animals. In a system where algae is intentionally cultivated, maintained, and harvested, neither eutrophication nor aquatic hypoxia are likely to occur. Living algae does not emit objectionable odors.
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Algae Production Concepts (overview) Like many good ideas (and certainly many of the concepts that are now the basis for renewable energy technology), the concept of using microalgae as a source of fuel is older than most people realize. The idea of producing methane gas from algae was proposed in the early 1950s. These early researchers visualized a process in which wastewater could be used as a medium and source of nutrients for algae production. The concept found a new life with the energy crisis of the 1970s. DOE and its predecessors funded work on this combined process for wastewater treatment and energy production during the 1970s. This approach had the benefit of serving multiple needs—both environmental and energy-related. It was seen as a way of introducing this alternative energy source in a near-term timeframe. In the 1980s, DOE’s program gradually shifted its focus to technologies that could have large-scale impacts on national consumption of fossil energy. Much of DOE’s publications from this period reflect a philosophy of energy research that might, somewhat pejoratively, be called “the quads mentality.” A quad is a short-hand name for the unit of energy often used by DOE to describe the amounts of energy that a given technology might be able to displace. Quad is short for “quadrillion Btus”—a unit of energy representing 1015 (1,000,000,000,000,000) Btus of energy. This perspective led DOE to focus on the concept of immense algae farms. Such algae farms would be based on the use of open, shallow ponds in which some source of waste CO2 could be efficiently bubbled into the ponds and captured by the algae (see the figure below).
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The ponds are “raceway” designs, in which the algae, water and nutrients circulate around a racetrack. Paddlewheels provide the flow. The algae are thus kept suspended in water. Algae are circulated back up to the surface on a regular frequency. The ponds are kept shallow because of the need to keep the algae exposed to sunlight and the limited depth to which sunlight can penetrate the pond water. The ponds are operated continuously; that is, water and nutrients are constantly fed to the pond, while algae-containing water is removed at the other end. Some kind of harvesting system is required to recover the algae, which contains substantial amounts of natural oil. The ponds are “raceway” designs, in which the algae, water and nutrients circulate around a racetrack. Paddlewheels provide the flow. The algae are thus kept suspended in water. Algae are circulated back up to the surface on a regular frequency. The ponds are kept shallow because of the need to keep the algae exposed to sunlight and the limited depth to which sunlight can penetrate the pond water. The ponds are operated continuously; that is, water and nutrients are constantly fed to the pond, while algae-containing water is removed at the other end. Some kind of harvesting system is required to recover the algae, which contains substantial amounts of natural oil. The concept of an “algae farm” is illustrated on the bottom of this page. The size of these ponds is measured in terms of surface area (as opposed to volume), since surface area is so critical to capturing sunlight. Their productivity is measured in terms of biomass produced per day per unit of available surface area. Even at levels of productivity that would stretch the limits of an aggressive research and development program, such systems will require acres of land. At such large sizes, it is more appropriate to think of these operations on the scale of a farm.
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There are quite a number of sources of waste CO2. Every operation that involves combustion of fuel for energy is a potential source. The program targeted coal and other fossil fuel-fired power plants as the main sources of CO2. Typical coal-fired power plants emit flue gas from their stacks containing up to 13% CO2. This high concentration of CO2 enhances transfer and uptake of CO2 in the ponds. The concept of coupling a coal-fired power plant with an algae farm provides an elegant approach to recycle of the CO2 from coal combustion into a useable liquid fuel.
Microalgae can also grow in saline waters that are not suitable for agricultural irrigation or consumption by humans or animals. The growth requirements are very simple, primarily carbon dioxide (CO2) and water, although the growth rates can be accelerated by sufficient aeration and the addition of nutrients. Algae pond operations are very simple. The algae are introduced into the pond and allowed to grow until they occupy 1% of the volume of the pond. Very high growth rates are achieved because the pond is constantly mixed by the paddle wheel and it is infused with an ample amount of CO2 and fertilizer. The paddle wheel rotates providing a current of 20 cm/s around the pond. The mixing is required to ensure that all of the algae receive the necessary amounts of solar radiation, CO2, and fertilizer required for optimal growth. The CO2 is injected into the algae pond in the form of flume gas from a nearby coal fired electric plant. The bubblers are spaced around the pond so that the CO2 is evenly dispersed throughout the pond. A 1,000 m2 algae pond operating in Roswell New Mexico consumes around 10,589 kg of CO2 each year. This is a miniscule amount considering that the average 785 MW power plant produces 19,488 tons of CO2 daily, or enough to support about 330,000 algae ponds. Copyright 2008 David Sieg
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Algae require phosphorus and nitrogen to grow at optimal rates. The phosphorus and nitrogen are pumped into the ponds from a central pumping station. The nitrogen in the form of ammonia or nitrate and must compose 0.8% of the volume of the pond solution to ensure maximum algae production. Likewise phosphorus in the form of phosphate and must compose 0.6% of the pond Both of these nutrients could be supplied in the form of municipal solid waste. Water must also be continuously supplied to the ponds because a certain amount is lost daily due to evaporation. Some tests have recorded an average water loss of 6.2 mm or 6.2 m3 of water per day. This must be replaced with a salt solution or fresh ground water depending on the species of algae used.
Centre-Pivot ponds for the culture of Chlorella in Taiwan. Largest ponds are about 0.5 ha in area.
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Raceway Ponds used for the culture of Spirulina platensis
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Example Lay-out of a Large Scale Biodiesel Farm Plot Overview
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General Plot Plan Oil Accumulation Ponds
Algae Breeding Ponds
Research Ponds
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Storage & Recirculation Pond
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Cross Section Ponds Measurement in meters
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Sea container Area All measurement in cm. Scale 1 cm. = 50 cm
Concrete Pavement Sea container 240 x 600 cn
500 x 500
Road
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Research Ponds All measurements in cm at Pond Bottom Level
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Oil Accumulation Ponds All measurement in cm at Pond
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Algae Breeding Pond All measurement not to scale
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Detail Drawings All measurement in cm. Not to scale
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Storage Pond All measurement in cm at Pond Bottom Level Not to scale
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The “Down and Dirty” Guide to
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Acknowledgments No work of this size and scope can be made without the input, and help of many people. Any work, by any author is a collaboration. In this respect, this work in no different. I like to thank the following people. Graydon Blair of www.utahbiodieselsupply.com Rick of www.b100.com Many of the photos come courtesy of www.biodieselphotos.com Both of these guys helped enormously and contributed time and support to making this a better book.. They also run businesses of honesty and integrity. Anyone seriously considering buying a processor or a kit should first look here. Keith Addison of www.journeytoforever.org Has one of the most comprehensive websites available. A wealth of information is available there. Hat’s off to you and thank you for making it the site as good as it is. “Bubble Washing” Courtesy of www.biodieselcommunity.org
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Introduction This work, is meant as an overview of the entire biodiesel process. ,It scratches the surface of the subject, and is meant as a starting point, not an ending. For more in-depth treatment of all subjects, you should consider getting the specialized products this web site offers. This work, however, is meant to get you started in the right direction. You will want, and need to branch out on your own from there as your personal situation dictates. All situations are different. I generally work and make biodiesel in Southeast Asia. The problems we encounter here are totally different than say, Portland Maine. Temperature, humidity, and many other factors come into play. Without question, biodiesel offers a way out of the petrol mess we have created for ourselves. Not on a national or international scale (yet) but on a personal one. It is entirely possible to create enough biodiesel for your heating and/or cooling, transportation, and other personal needs. Biodiesel also has the added benefit of being good for the environment. If that wasn’t enough, the by-products of biodiesel can, be turned into soap, fertilizer, and other equally useful items. Your aim in Making Biodiesel at Home can and should be to create an energy source that can be used economically, as well as a complete biological circle. Nothing wasted, everything used. Read this all the way through, then print out a section at a time as you work through the processes involved. Don’t get discouraged. Trial and error are inevitable. Good luck, you’re about to start an incredibly exciting journey.
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Why Make Biodiesel at Home? Biodiesel fuel is a fuel you can make at home and quit depending on oil companies to provide you with basic human needs, like heat and transportation. It's a fuel that burns cleanly and efficiently. Biodiesel fuel is BETTER than the diesel fuel you buy at the gas pump. Biodiesel is cleaner than regular diesel. It cuts down on targeted emissions - which means it's better for the environment and better for your health. It is also one of the only alternative fuel recognized and endorsed by European as well as the US government. Keep reading to read what the US government is saying about biodiesel... ...(From the National Renewable Energy Laboratory document) 78.3% reduction in greenhouse gases 55.4% reduction of particulate emissions (black sooty cloud behind your car) 56.3% reduction of hydrocarbons 80-90% reduction of mutagenicity (cancer-causing agents) 100% reduction of sulfurs
(a major component of acid rain.
Save Money. By making biodiesel fuel at home you can usually realize a savings of close to $2.00 a gallon. Imagine what they would mean to your home heating bill every month. Biodiesel is EASY to make. You can make biodiesel in your kitchen!. If you can mix bread, you can make biodiesel. Biodiesel provides excellent engine performance. Your diesel engine will run better, cleaner and last longer on biodiesel. The production and use of biodiesel creates less carbon dioxide emissions compared to regular diesel. Causing less damage to the environment.
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The material for making biodiesel is renewable and biodegradable. You can make biodiesel from vegetable oil such as palm oil, rapeseed oil, soy Oil, peanut oil, etc. You can even make it from used vegetable oil from restaurants. Petroleum oil prices are skyrocketing. With no end in sight. Biodiesel is just now gaining popularity. It is the best time for you to start experimenting with biodiesel and if you know how to make it, then when biodiesel is in demand, you will be in a position to not only save money, but also make money. Biodiesel can be used by itself (B100) or blended with regular diesel in any proportions. So, when diesel is too highly priced, like it is now, your biodiesel will be very much in demand. No modification is required on your diesel engine. Biodiesel operates in conventional combustion-ignition engines, from light to heavy-duty just like regular diesel and no engine modifications is needed. Fossil fuels are depleting. Fossil fuel products have been used by mankind as a source of energy and it was assumed that they would last forever. Times have changed: with fossil fuel on depletion and global warming on the increase, it is time to create a sustainable world. It doesn’t rely on unfriendly and/or unstable governments to produce. Sooner or later, and it looks like real soon, we are going to have to start coming up with the lion’s share of our own energy needs. It’s always better to rely on yourself than someone else. Best of all is the GREAT feeling of freedom, independence and empowerment it will give you. Creating your own fuel in your garage, enough for your own needs and friends, heating and/or cooling your house, and either saving or making a ton of money at the same time. Is it the answer to all the world's energy woes? No, it's not. But it can be the answer to yours. Like any answer biodiesel fuels have their advantages and disadvantages. Why not explore these pages and find out for yourself if this could work for you?
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What is Biodiesel? Thinking that you can use biodiesel as a natural, biodegradable fuel, that leaves little impact on the environment, that can be made from recycled waste oil and even made in your own garage probably seems a little too Hollywood for you. I don’t blame you. I thought so too when I first started looking into this method. The ugly truth is, most alternative fuels leave much to be desired. There is however, a viable alternative. I’m convinced biodiesel could be the future of alternative fuels. Why? There are many, many reasons for this. No other fuel has so many natural, built-in advantages. For example... · It burns much cleaner than fossil fuels, · Is made from renewable resources, ·
· · · · · · ·
It can actually be made in your very own kitchen.
It contains no petroleum and as a result it is environmentally friendly. It is made using vegetable oil, alcohol, and lye, all of which are easily renewable resources, so when you power your car organically, you are using a fuel that only uses renewable resources. It is recognized by the US Government and the EPA as fuel It is covered by most vehicle manufacturers warranties It requires no modification of your engine It doesn’t require that the nation reorganize it’s entire energy infrastructure. It doesn’t rely on unstable and/or unfriendly governments. And many, many more. This is just the tip of the ice berg.
For many years, various alternative fuels simply weren’t viable. Because of this they never became mainstream. Today with oil prices soaring, the Oil Companies posting record profits while the rest of us are beaten down by high energy costs, it is growing in popularity. The Vegetable oil based fuels of yesterday required specially modified engines in order to be of any use and the average person usually had no interest in modifying their vehicles. Why should they? Gas was cheap, the car manufacturers would also void your warranty’s. Not so with biodiesel. Sure you might need to buy a diesel car. So what? Think of the headaches, not to mention the money you will save. Biodiesel can be used in place of the regular petroleum in the car you drive everyday. No alterations or modifications are needed. That means that it can also be used in every machine that requires fossil fuels, from generators, to farm equipment, to the family car, to the furnace heating your home. Can you honestly tell me you wouldn’t want to get rid of that $500 bill every month? Considering that this fuel costs about seventy cents a gallon to produce it is a realistic alternative to fossil fuels that is starting to catch on.
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Now it is available for purchase in selected cities as well. It can be bought directly from the manufacture or distributor and if you search around, you might even find a few gas stations that allow you to pump it into your car. Biodiesel pumping stations are starting to crop up at scattered locations throughout the country. If you aren’t with in the proximity of a station that sells biofuels, you can even make it yourself in your kitchen, or you can buy a biodiesel kit fairly cheaply. If you’re handy around the house and have some tools, you can even make your own processor. There are many home built “stills” on the pages of this web site. The process for making biodiesel at home isn’t much harder than concocting a high school science experiment. The ingredients are easy to find at almost any hardware store and even the equipment is basic. By mixing lye together with antifreeze, sodium methoxide is formed. When you mix sodium methoxide with vegetable oil it transforms itself into two useful substances, glycerin and biodiesel. Glycerin is used in making soap and if you ever whip up a batch of biodiesel, you can use the resulting glycerin by-product to make your own homemade soap. Bet you can’t do that with ordinary diesel! Biodiesel is an amazing discovery that will revolutionize the way we view fuel. Rudolf Diesel was at least 100 years ahead of his time. It is also environmentally friendly, it is just as efficient as the petroleum diesel we now burn, but much less expensive. Because you can make it yourself using commonly found ingredients, using biodiesel means that you will never be dependant on oil companies again.
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Biodiesel FAQ: 12 Most Frequently Asked Questions 1.) OK, So what do I need to do to convert my car to biodiesel? First and foremost, you need to have a diesel engine. Biodiesel CAN NOT be used in a gasoline engine. Having said that, any engine that runs on #2 diesel can also be run on biodiesel. There is really nothing you need to do and nothing you need to convert. Conversion becomes necessary when you want to run your diesel engine on Straight Vegetable Oil (SVO) For some pre-1994 model vehicles it is said that you need to replace your rubber hoses with synthetic ones. But truthfully, unless you have a leak, I wouldn't bother. 2. I have heard that biodiesel will eat or degrade the rubber in my fuel system? Biodiesel is a solvent and a degreaser (a good one) and as a solvent, yes, it will eat rubber. The truth is, petroleum diesel with a high sulfur content does this too, only slower. Biodiesel acts a lot like Ultra Low Sulfur Diesel (ULSD) that is now fast becoming the diesel standard. Also, since 1993, diesel engines and equipment have been reworked and redesigned, using synthetic rubber with ULSD in mind. The auto makers have been phasing out rubber from the fuel systems themselves. This is resulting in fewer fuel leaks for diesel and biodiesel users alike. If you have a pre-1994 vehicle with rubber fuel hoses and are experiencing leaking problems, then yes, you should replace them with ULSD compatible hoses. 3. Should I replace my fuel filter before using biodiesel? Not necessary. As stated before, biodiesel is a solvent and as such will also start cleaning your diesel engine and your fuel system. What it is going to clean is the sludge left behind from regular diesel fuel. Over time, this sludge can clog your filters. The truth is, biodiesel will keep your car's fuel system very, clean. If you buy an older diesel engine car, (say 30,000 + miles of petro-diesel usage) the degreaser cleaning properties of biodiesel will clean the system of the accumulated diesel sludge/debris first. It might take weeks, months or years, who knows? Engines are funny. After a while, you may need to change your fuel filter, but you'll need to change them anyway as a normal maintenance procedure. If it clogs up, or you are having a problem (loss of power, smoking, coughing, trouble starting, etc.) and you suspect it could be related to the fuel filter, then by all means, switch it out, they are fairly cheap anyway. Simply change out the filter and chances are your problems will go away. It's not a bad idea to keep an extra fuel filter on hand anyway...just in case. The good news is, once your engine's fuel system has been cleaned, it will stay incredibly clean from then on.
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4. Is it true that a gradual increase in biodiesel percentage in my diesel fuel is the best way to start using biodiesel in my vehicle? Not necessary. There is no mechanical reason that I know of to support this. Any blend of biodiesel, from 100% biodiesel (B100) to 100% diesel can be used in any diesel engine. 5. If I switch to biodiesel and don't like it, are there any problems with switching back to diesel again? No problems at all. You can switch back and forth as much as you like. 6. How are automobile makers, and specifically their warranties, responding to biodiesel usage? It's kind of interesting to watch, truthfully. As the biodiesel industry gets older and wiser, more and more OEMs (Original engine Manufactures) are warming up to this idea and making positive statement about 100% biodiesel and this is reflected in their warranties. The truth is, it's kind of tough for them to argue the fact. The diesel engine, after all, was designed for this. Caterpillar, John Deere, and New Holland all accept and explicitly warrant B100 biodiesel in their engines. Others are taking a more "wait and see" attitude. They are warranting blends like B20, or B5 but stop short of wholeheartedly endorsing the idea. Other say they "neither oppose nor endorse" the use of biofuels. This is where it gets interesting; Mercedes and Volkswagen both sell cars in the USA with diesel with warranty issues in Europe, but here in the good ol USA, they don’t/won’t support the use of biodiesel or the biodiesel industry. So bottom line? One, check your warranty. Two, if a OEM wants to deny a warranty based on biodiesel use, they can. But legally, they have to show a compelling reason that biodiesel hurt the engine. Which would be very hard to do. This is a very good reason to use ASTM (Commercial biodiesel) fuels, especially in newer cars or trucks. 7. What is biodiesel made from, besides vegetable oil? Because modern diesel engines have been modified to meet diesel #2 viscosity standards, straight vegetable oil like the kind Rudolf Diesel used in 1912, is much thicker. This is the thing which kept biodiesel out of the energy/fuel playing field for so long. What has happened recently is a process called "transesterification." This process is used to thin the vegetable oil and remove the glycerol molecule from the vegetable oil and replaces it with methyl alcohol , or methanol. In order to do this, the methanol is mixed with sodium or potassium hydroxide (Lye) before being mixed with the vegetable oil. This is the basic process. Commercial production requires more ingredients and more processes, but you get the picture.
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8. Should I worry about residual methanol, lye, or glycerol? For home-brewers, the possibility of residual ingredients or by-products in the brewed biodiesel is a compelling reason to "wash" then test the biodiesel. Biodiesel that is commercially sold, is regulated and made to the ASTM standard, does not allow for residuals to be present. Therefore, you should have little worry with commercial biodiesel . 9. Are there special storage considerations for biodiesel? Is it safe? The first answer is "No" and the second answer is "Yes" It certainly isn't a bad idea to read and understand about basic diesel storage techniques because many of the same issues apply. Of course, you don't want it around a source of high heat and exposure to air and water should also be taken into consideration. 10. I'm thinking about converting my car/truck to run on straight vegetable oil (SVO) because it does not involve all the chemicals, and is cheaper. Why doesn't everyone just convert to SVO? As we have said, just because the first diesel engines were designed to burn vegetable oil, a lot has changed in the engine world since 1912. Biodiesel fuel, to work efficiently in a modern diesel, we need to lower the viscosity (thickness) of the vegetable oil. We accomplish this through the biodiesel production process. It can also be accomplished by modifying the engine with a SVO Conversion kit. But additionally, there are other reasons not to use straight vegetable oil. One, it still contains glycerol which doesn't burn as cleanly as biodiesel and can leave deposits behind in the injection chambers. Two, SVO still needs to be de-watered, filtered and heated prior to introducing it into your tank. Also, filtering SVO can be very tedious to say the least, needing lots of time and energy, not to mention equipment and tools. 11. Will biodiesel work in kerosene heaters and/or oil furnaces? The short answer is...yes. Biodiesel is 100% compatible with diesel #2. There are no worries in that regard. One of the compelling reasons to buy a biodiesel kit in my opinion is to get rid of that financial albatross, called "heating oil" in colder climates. A biodiesel kit can pay for itself in a matter of months, one winter definitely. Kerosene, which is also known as diesel #1, or heating oil #1, is thinner than diesel #2. This, of course, requires a bit more experimentation, but generally, if a heater is designed for kerosene, then it will work with a biodiesel blend. (Meaning a higher percentage of kerosene and a lower percentage of biodiesel) 12. Are there any other applications for biodiesel? Yes, lots. For example, generators, air compressors, fishing boats, farm equipment, kilns, ovens, saw mills, ships, semi trucks, trains, and that is a short list. The by-products can also be used for soap making and a organic fertilizer. It can also be used as an industrial solvent and/or degreaser. We would be interested in hearing about any other uses as well.
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Biodiesel Advantages and Disadvantages The biodiesel advantages and disadvantages are listed below. However, many of the disadvantages can be mitigated, such as not being able to use biodiesel in lower temperatures. Advantages: · · · · · · ·
So, in a nutshell...
Made from non-petroleum, renewable resources that can be produced domestically Can be used in most diesel engines, especially newer ones Less carbon monoxide, particulates, and sulfur dioxide emissions 78% less carbon dioxide (CO2) production Biodegradable Nontoxic Safer to handle
Disadvantages: · · · · · ·
Slightly lower fuel economy and power (10% lower for B100, 2% for B20) Currently more expensive More nitrogen oxide emissions Transportation & storage of B100 require special management B100 generally not suitable for use in low temperatures Concerns about B100’s impact on engine durability Some other things to consider:
For those of you who like the details...There are some things you need to be aware of. First is ... ...Filters... Conventional diesel is pretty filthy stuff. Not only is the black cloud spewing out behind your car dirty, but the fuel itself leaves a sludge in the tank and fuel system itself. Your biodiesel car is a clean machine. Biodiesel is a clean fuel. Not only that but it will also clean your engine — (There’s a reason one of the interesting by-products of biodiesel production is soap) it does a great job of cleaning up the residue commercial diesel leaves behind. The problem is, then all the freed crap blocks up the fuel filter. When you first switch to biodiesel, check the fuel filters on a weekly basis and change them when needed. The first few weeks are the most critical. It wouldn’t hurt if you fitted a second cheap filter upstream of the main filter for awhile on your biodiesel car until you cleaned your engine up.
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If a car has been hanging around for a long time with commercial diesel in the tank, (as with a lot of secondhand cars up for sale,) the bottom of the tank may have rusted (water content is a common problem with commercial diesel). Adding biodiesel will free up the crud and rust, and it could clog the particle filter inside the tank. At worst what happens is the biodiesel car simply stops running, starved of fuel. More likely the engine will start steadily losing power at first, probably for long enough to get you there before it stops, the first time anyway. It doesn’t happen all the time, but it happens. It’s happened to a few older Mercedes in the US, after running on 100% biodiesel for about a year. What you can do in that case is take the particle filter out of the tank and replace it with an external filter, you’ll need to check this often as well, and after awhile it will stay clean. :Keep in mind though, “If it ain’t broke, don’t fix it.” There’s probably no need of removing the particle filter from the tank UNLESS there’s a rust problem. Rubber... Rubber parts in the fuel system may rot or corrode as time goes by with biodiesel cars. Especially if you’re using 100% biodiesel (B100). Newer cars, since the mid-1990s or so, use resistant parts. Biodiesel is used in many older engines without any problems. If necessary, check with your vehicle’s manufacturer. Viton parts are best. Just do it, go ahead and use biodiesel, and wait and see. If you do have problems you should, with a little common sense, see it coming. You’ll have warning and it’s easily fixed. Cold Weather... Biodiesel doesn’t particularly like cold weather. Between 1 degrees and 10 degrees Fahrenheit it tends to gel or congeal. If you live in a cold weather climate, this something that needs to be taken into consideration. The answer could be as easy as storing you biodiesel and your car in a garage. You can also preheat the biodiesel in a storage tank. My point here is, with a little thought, this problem can also be gotten around. ...Also.. No serious discussion of biodiesel, or any subject for that matter, without looking at the “downside” of the picture. There are things you need to consider before undertaking this project, or any project. Not that anyone is trying to scare you off from making your own biodiesel. But a smart person looks at all angles. Biodiesel Articles: Some of the issues concerned have to do with safety. Others concerns have to do if you are considering selling the product. Still others have to do with the process itself. Let’s look at all of them... First..., ...slopping some homemade biodiesel into your engine without first reading the warranty for your vehicle is NOT a wise thing to do. Manufacturers differ. What you’re trying to do is avoid voiding your car’s warranty. READ your OME warranty YOURSELF. (Don’t take someone’s word for it.) To stay on the safe side.
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Secondly… If you’re planning on giving away or selling your biodiesel to friends, family, or anyone else, keep a few things in mind. One, if it wreaks THEIR car, it’s YOU, not the manufacturer who could be held responsible. Also remember, it could also be illegal to sell biodiesel that is not up to federal fuel grade standards. You need to check local, state, and federal law on the subject. Lastly... The biodiesel process itself can be time consuming, and require a lot of work on your part. There are not any free lunches. You will need to set aside some time for experimenting, and trying different methods. Be sure to make small test batches first and gradually work your way up to a larger scale. You might experience a few failures. Don’t take it personally, just try it again. Biodiesel will vary from person to person, climate, humidity, and your ingredients, such as the quality of the vegetable oil you are using. Also be sure to test any fuel you make prior to using it. Make sure that you have ended up with a quality, fuel grade product. Otherwise you could be risking damage to your diesel engine or diesel car. Biodiesel home making is not for children. Be a responsible adult. Many of the materials used to make biodiesel if handled wrong can hurt you. Read the safety page to get started. Now, the good news… Lots of people are doing this. In Europe and in the United States. This is not wacky science. It has been used for almost a century...especially by farmers. The diesel engine itself was designed with vegetable oil in mind as a fuel source. Large numbers of “real” people all over the world are discovering they don’t have to be a slave to the Oil Companies any longer...and you can too. Large numbers of ordinary people from all over the world (especially farmers!) have been biodiesel home making for over half a century. It’s true that some of the ingredients are toxic, but that shouldn’t stop you. For example, Lye that is used in most biodiesel recipes is sold in supermarkets and hardware stores as a drain cleaner. It is also an ingredient used in soaps. Methanol, another ingredient is used can be bought in the same places over the counter as it is the main ingredient in fondue fuel, as an automotive fuel additive, even barbecue fuel! So don’t listen to people who say this is “Extremely dangerous.” These are the same people McDonalds had to warn about coffee being hot. It’s perfectly safe if you’re careful and sensible about the handling and mixing of the product then there is no need to be apprehensive. As long as you educate yourself, exercise proper concern for yourself and responsibility towards other people, there is no reason you can’t be enjoying lower energy and fuel costs, saving money and the knowledge that you’re being kind to the environment.
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BIODIESEL
SAFETY
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Biodiesel Saety Please read this whole section right to the end. OK, this biodiesel safety report is meant to make you aware of certain fundamental facts of life when it comes to biodiesel. Nothing to get shook up over, mind you. Just playing it safe, and not being an idiot. This is where biodiesel safety comes in. Always... • • • •
Wear proper protective gloves, apron, and eye protection and do not inhale any vapors EVER.
Methanol can cause blindness and death, and you don’t even have to drink it, it’s absorbed through the skin. Sodium hydroxide can cause severe burns and death. Together these two chemicals form sodium methoxide. This is an extremely caustic chemical. Treat this with respect. Here’s the worst part, methanol and lye are poisons. It get easier from here on in. Keep reading... Methanol: Methanol Causes eye and skin irritation. It can be absorbed through intact skin. This substance has caused adverse reproductive and fetal effects in animals. It is considered a Dangerous Flammable liquid and vapor. It can be Harmful if inhaled. May be FATAL or cause BLINDNESS if swallowed. May cause central nervous system depression. May cause digestive tract irritation with nausea, vomiting, and diarrhea. Lye: Is a corrosive. It may be fatal if swallowed. It can be harmful if inhaled. It causes burn to any area in contact, i.e. skin. It reacts with water, acids, and other materials. So, needless to say, this not good stuff. Never fear. Use basic safety precautions and live a long, full life. The minimum precautions are... • chemical proof gloves, • apron, • eye protection and dust mask. However many people also add lab coat, or lab apron, and full face shield. These are dangerous chemicals — treat them as such. • Gloves should be chemical-proof with cuffs that can be pulled up over long sleeves • no shorts or sandals. • Always have running water handy, either in a slop sink or a garden hose when working with them. • If you ever need to flush out your eyes or get off any exposed areas of skin.
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The main danger is when mixing the methanol and lye. The best advice is not to expose yourself to the fumes in the first place. The main danger is when the methanol is hot — when it’s cold or at “room temperature” it fumes very little if at all and it’s easily avoided, just keep it at arm’s length whenever you open the container. • Don’t use “open” reactors — processors should be closed to the atmosphere, with no fumes escaping. • All methanol containers should be kept tightly closed anyway to prevent water absorption from the air. Transfer methanol from its container to the methoxide mixing container by pumping it, with no exposure. This is easily arranged, and an ordinary small aquarium air-pump will do. The mixture gets quite hot at first, but the container is kept closed and no fumes escape. When mixed, the methoxide is again pumped into the (closed) biodiesel processor with the aquarium air-pump — there’s no exposure to fumes, and it’s added slowly, which is optimal for the process and also for safety. Once again, making biodiesel is safe if you’re careful and sensible — nothing about life is safe if you’re not careful and sensible. “Sensible” also mean not over-reacting, as some people do: “I’d like to make biodiesel but I’m frightened of all those terrible poisons.” In fact they’re common enough household chemicals. Lye is sold in supermarkets and hardware stores as a drain-cleaner, there’s probably a can of it under the sink in most households. Just be careful. Methanol is the main or only ingredient in barbecue fuel or fondue fuel, sold in supermarkets and chain stores as “stove fuel” and used at the dinner table. It’s also the main ingredient in the fuel kids use in their model aero engines. So get it in the right perspective: be careful with these chemicals — be careful with ALL chemicals — but there’s no need to be frightened of them. Hazards The main hazards are… • poisonous fumes, • dangerous chemicals, • and fires. For poisonous fumes, the best advice is not to expose yourself to the fumes in the first place. Don’t use “open” reactors — biodiesel processors should be closed, there is an entire e-book on my website on how to build biodiesel processors. All of the models shown in the e-book are closed reactors.
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Always have running water available to wash off any splashes. The workspace must be thoroughly ventilated. Open the windows or garage door, set up some fans, even get an exhaust fan for near your biodiesel work station. No children or pets should be allowed in the area when you are making biodiesel. Be smart. You can teach Junior all about it later.
Do NOT inhale any vapors. Cartridge respirators do not work against methanol. Organic vapor cartridge respirators are more or less useless against methanol vapors. Professional advice is not to use organic vapor cartridges for longer than a few hours maximum, or not to use them at all. Only a supplied-air system will do (SCBA — Self-Contained Breathing happened. It’s easy to avoid fires in the first place. Most important, again, use closed processors, Don’t screw around making a processor unless you’re very sure of your abilities. The main fire hazard is using an open reactor and • Poor ventilation in the presence of an ignition source. •
Ignition sources can be: •
• • • •
•
Using combustible fuels as a direct heat source (propane, natural gas, WVO, wood, etc.), rather than a heat exchange system where the flame is far removed from the processing area. Open electric motor housings, rather than TEFC motors (Totally Enclosed FanCooled AC Motors) or explosion proof motors. Disconnecting an electrical appliance by pulling out the wall plug, rather than using enclosed switches. Any open flame. Other fire sources can be over-taxed pumps and motors in close proximity to combustible materials (garage walls, plastic barrels, almost anything), oversized breakers and/or fuses, undersized wiring (such as 14/2 Romex) for higher amperage draws. And there always is the danger of spontaneous combustion in the presence of oily rags, especially when working with drying oils such as hemp and linseed. This threat decreases as the saturation of the oil/fat increases.
The Moral of the story? Keep chemical fire extinguishers around your work place. Now that I have managed to scare you, just realize that Methanol is the fuel used in most Model airplanes. In the USA methanol is available in small quantities as HEET brand fuel line antifreeze (Yellow bottle) Lye is an every-day drain cleaner. Both are freely available in most large shopping centers. Remember all these ingredients are available in the normal course of everyday life. Nothing to be afraid of, yet at the same time, play it safe, don’t get careless and you’ll do fine.
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A Visual Overview of the Biodiesel Recipe Process 1.) First you take a sample size of Waste Vegetable oil (WVO)
2.) Heat the WVOto 120 F. 3.) Check the titration level (Used Vegetable Oil) 4.) Mix the lye and methanol together
LYE
5.) Mix lye and methanol blend into WVO and blend together.
6.) Allow time for separation. The mixture will sepaBiodiesel rate into two layers, biodiesel on top, glycerin on the bottom. Glycerin
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NO HA T ME
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7.) Drain off the glycerin and “wash” with tap water
8.) Allow time for water to settle, biodiesel will float to the top.
biodiesel
water
9.) Drain off water.
10.) Put it into your car and
go. Be sure to smile and wave as you pass the gas pump.
Now, admittedly, this is a simplification of the entire process, but not by much. It also depends on how complex you want to make the process as well. This is intended not to be the “absolute process” as it is to be a “visual overview.” As you can see, it’s not that difficult.
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Making Your First Batch of Biodiesel OK, you’re going to get your feet wet now. The purpose of this chapter is to see if making biodiesel is something you want to do, and are capable of doing. It is a way to test the biodiesel waters to get your feet wet without getting soaked financially. Not that it takes a rocket scientist, but some people are better at some things than others. There’s no use in spending 1000’s of dollars to find out biodiesel is something you are going to hate doing. On the other hand, you might find out this not only is something you like doing, but you’re really good at it. This is a simple process. The goal is to make a small test batch from start to finish. By the end of this unit, you will know the following things. Yes, this is something I CAN do. Yes, this is something I WANT to do. Biodiesel is not complicated. As I’ve said elsewhere in my book, if you can make barbeque sauce, you can make biodiesel, and it’s true. This is basic chemistry, and chemistry is nothing more than mixing, cooking and waiting for a reaction. There is going to be those who want to over-complicate this...don’t. Simply take this a step at a time.
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Making Biodiesel in Your Kitchen Making biodiesel in your kitchen is intended as an overview of the biodiesel process. While this method of making biodiesel is perfectly safe, you are strongly encouraged before undertaking this activity, or any activity involving chemicals, to read the Safety Information that comes as a bonus with this material before attempting this at home. Improper use of these chemicals, or any others, can be dangerous. This is presented for educational information only and assumes you are taking full safety precautions. This method of making biodiesel is perfectly safe. You do need a brain though. Use yours. If you can mix barbeque sauce, you can make biodiesel. Chemistry is a lot like cooking...measure and mix the ingredients and wait for a reaction. It is entirely possible to make enough fuel at home in a safe, easy, professional manner for all your own needs. You can do this for less than $1.00 a gallon. This will enable you to have enough to run your cars, or trucks, even heat your home in the winter. There is no reason you can’t be saving money on your energy needs in a very short time. This "homebrew" kitchen method is good for NEW vegetable oil ONLY. Try it to get your feet wet, without getting soaked financially, to see if making biodiesel is a good alternative for you. Here are the materials you'll need making biodiesel... 1 liter of clean/new vegetable oil. The cheapest you can find. Lye (AKA "caustic soda") you are going to need a least 4 grams. You can find this at the supermarket in the cleaning section around drain cleaners. Check the contents; it should say "caustic soda" (DO NOT use Drano) When you buy lye (sodium hydroxide) you have to be careful to get the pure form of the lye. Many types have other chemicals in it. The bottles shown came from ACE Hardware. They did have pure lye. The "lye" bottles at Home Depot and Walmart had additional ingredients. So be sure to read the ingredients and only go with one that only lists sodium hydroxide. For you chemical types, NaOH is the chemical compound. Methanol. You can find this in Auto supply stores. It usually lives in the gas line antifreeze section. For this recipe you can use HEET gas line antifreeze, the one in the yellow bottle. Pure methanol is sold as gas-line antifreeze because it absorbs water in the gasoline and prevents the water from freezing. This is not the cheapest source of methanol but is convenient for our small scale production. Another source is racing fuel methanol, which is much cheaper per gallon. Copy-
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Here's the equipment you'll need making biodiesel... (One) 2 liter plastic bottle. It should be clean and dry. A funnel that fits the bottle above A dry, sealed container to mix the methanol and lye. It is important that it be able to seal securely and tightly. If you were to turn this container upside-down, nothing should leak out. Metric scales are also helpful. (To measure out 250ml of lye) or a teaspoon measure A measuring cup with metric measurements to measure out the methanol
You could also add to this list... Plastic safety gloves. Plastic lab apron. Face shield and/or eye protection. OK, for the last time, read the safety instructions. Making biodiesel is not a science project or a family activity. (at least at this point) When mixing the lye and methanol together, DO NOT breathe the vapors! The resulting mixture, "methoxide," is a poison. It's nothing to get alarmed about, but it is something to be informed and knowledgeable about. Be careful and be cautious. · . Here's the recipe... Open the windows, turn on the fan. In a well ventilated area, Measure 250 mL (a little more than a cup) of room temperature methanol into the bottle. Continue adding methanol until the white bottle is about 3/4 full. Put the cap on the white polyethylene bottle and the methanol bottle. (Again, we're always trying to keep moisture in the air from being absorbed.) Copy-
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Measure out 4g of NaOH (lye) (about half a Teaspoon) and add to the methanol in the bottle screwing the lid down tightly to prevent any leaks. Be sure to close the bottle of lye as soon as you get the right amount weighed. Lye will absorb water out of the air making it heavier and less effective.
Swirl the mixture by hand until all the lye is dissolved. As you start mixing the temperature will increase. Don't get nervous, and don't panic. This is what is supposed to happen and may take 10 minutes or more.
Here's what you are going to do... Heat 1 Liter of unused clean, vegetable oil, 60 °C/140 °F Using a funnel, pour the liter of oil into a DRY 2 liter plastic container. The bottle should now be half-full. Be careful not to overheat the oil or it may melt the plastic. In a well ventilated area, pour the mixture of methanol/NaOH (methoxide) on top of the oil using the same funnel. DO NOT breathe the vapors. Remove funnel. Put the top back on the bottle and screw it down TIGHT. You want no liquid to be able to escape. Shake vigorously for about ten seconds or twenty seconds, 30 or 40 good shakes Put the bottle on a table and let it settle. In about 10 minutes or so, the oil will change color from a chocolate -coffee color to a rich, darker brown. Then the byproduct (glycerin) will start to settle out and separate on the bottom of the bottle. You should see a clean line of separation between the two liquids. The biodiesel will be on the top. Within an hour, most of the glycerin (bottom layer) will be settled out. This is called separation.
Copy-
Picture courtesy of http://biodiesel.infopop.cc/groupee
You should now have a bottle containing lighter ambercolored (or clear, if you’re lucky) biodiesel on top and a layer of darker glycerin on the bottom.
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At this stage of the process, the biodiesel will be very cloudy, (so don't panic) it will take a day or two more for it to clear completely. Put it in a cool, dark place and let it do it’s thing. Usually the glycerin layer is about the same as the amount of methanol used. Once the it is completely settled, open the container and using your thumb drain the biodiesel out, leaving the darker layer (glycerin) behind. Depending on your expertise at doing this, the mixture is technically ready to use as a fuel. What you have done is altered the chemical properties and made thinner and it more combustible for use as a fuel. I told you making biodiesel was easy. Now you’ll use a simple wash method...
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Washing Biodiesel An Easy, Painless Technique to get you started Having just produced your first (test) batch of biodiesel this is an easy, fun and painless method of learning the washing biodiesel process. You can wash a small batch of biodiesel in less than an hour using this method. It’s easy and it’s safe, please keep reading... Be aware that unwashed biodiesel contains soap. If you agitate (shake it) your first few washes hard and/or violently, there is a real likelihood that the water, soap, and biodiesel will form an emulsion (otherwise known as “glop”) that may take days, weeks (or never) to separate. THE TECHNIQUE: The three important steps in washing biodiesel are GENTLY GENTLY GENTLY to begin with. Wash One: · Pour 1 liter biodiesel into a 2 liter bottle. · Gently pour about 500ml (about 2 cups) body temp water (not hot) into the bottle. · Replace the top and make sure it doesn’t leak. · GENTLY rotate bottle end for end for about 30 seconds. · After 30 seconds place bottle upright on a table. · If you have been GENTLE the water and Biodiesel will start separating immediately. · You will notice the water is not clear, but a milky color. · Remove the top and using your thumb as a stopper, turn the bottle upside-down and drain the water using your thumb as a valve. You have finished wash one. Wash Two: · Pour in another 500ml water and repeat wash one, except rotate GENTLY for about 1 minute. · Drain as in wash one. You have finished wash 2. Wash Three: · Again pour in another 500ml (about 2 cups) water and... · GENTLY GENTLY GENTLY shake bottle for a minute or so. · When water and biodiesel separate discard water in same fashion as before. Wash Four: Another 500ml water and a bit more aggitation for about 1 min. After seperation of water and biodiesel Drain as above.
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Wash Five: You should now be able shake fairly vigorously. Testing For Completion: Washing is finished when after shaking, water is nearly clear. Be aware that in your later washes you should be able to shake violently. The water and oil will take longer to separate because the water forms tiny bubbles in the biodiesel that take time to settle out. Washed biodiesel is VERY CLOUDY, much lighter in color than the original bio diesel and looks terrible. After a day or 2 settling and drying it will clear.
Congratulations!!! You’ve made biodiesel! At this point, if the biodiesel is clear enough to read a newspaper through, (A quick quality test) then you should be able to use it. Go ahead, try it! Your exhaust should smell sort of like popcorn, and no black greasy, smoke. Cool, huh? This is the process in a nutshell. You mix the lye and methanol together Pour the mixture on top of the vegetable oil and mix that together. Let it seperate Pour off the by-product (Glycerin) Wash Quality test Use it with a smile.
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Pre-Production Stage
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How Much Biodiesel Will I Need to Produce? What you want to do is think of this in terms of a complete cycle. Meaning...How many of my energy needs can I switch to biodiesel. The most common and immediate are heating oil, and diesel for transportation. So, let’s look at those first. How may gallons/liters do I use for heating and/or cooling? How many gallons/liters do I use for transportation? How many gallons/liters do I use for other uses/ (generators, farm equipment, etc.) The good news here is that there really is no complicated formula. Add it up, and this is the amount you will need to produce over the course of a year. So, for example, if you were an average family with a 3 bedroom house, and a couple of vehicles... Home heating/cooling: 250 gallons per month, 6 months of the year. 1,500 gallons per year. Transportation: 100 gallons per month, 1200 per year Now of course, if you are running a generator, farm equipment, heavy trucks. Or any heavy machinery, your savings will be much greater.
SAVINGS: $500 (per month) ($3,000 per year) SAVINGS
$250 (per month) $3000 (per year) SAVINGS TOTAL
This means you’ll need to produce approx:: 2700 gallons per year or 255 per month.
$750 (per month) $6,000 (per year)
Which means, you’ll need a processor capable of producing at least 52 gallons per week, or approx: 200 gallons per month. Getting a 100 gallons processor and running it a couple of times per month, especially if it an automatic unit, makes this very doable. However, these figure need to be offset by production costs of lye, methanol, and the processor (until it is paid for) and any charges resulting from WVO collection. Now, if you get a generator, run a bank of batteries, then you can power your entire house, and significant saving will result. That, however, is beyond the scope of this book.
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Biodiesel Production Process (An Illustrated Overview) This is an simplified version of the biodiesel production process. It is intended to give you an visual “overview” of the actions and processes involved. The process is not difficult, so don’t get alarmed. We are not getting serious yet, You’re just looking to see if this is something worth considering. The main biodiesel process is accomplished in 3 different tanks; • • •
Processor Tank, Catalyst Premix Tank, Wash Tank.
Note: 1.) Keep in mind, a diesel engine can be run on straight vegetable or animal oil. (SVO or “Straight Vegetable Oil”) It can even be run on Waste Vegetable Oil. (WVO) That’s right folks, you COULD just run down to the local market and get some Crisco and slop it into your tank. This however, is not a good idea. One, while your engine may “run” on canola, it won’t “Start” on it. Because SVO takes a higher temperature to ignite. Which means the engine must be warmed up before vegetable oil can be used. 2.) SVO or WVO doesn’t burn cleanly or efficiently and emits more pollutants than biodiesel. 3.) Lastly, the MODERN diesel engine is simply not designed to run on SVO or WVO to do so, without gumming up and generally making a mess of things. 4.) In other words, don’t do it until you have done a biodiesel conversion. OK, moving on... What we are doing here is looking at the actions and/or steps involved if you were to buy a biodiesel kit or build your own processor and what to expect.
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Processor Tank
1.) What we are going to do is fill the Processing Tank with vegetable oil (SVO) or waste vegetable oil (WVO) heated between 50c and 60c Straight (SVO) or Waste (WVO) Vegetable Oil
2.) A measured amount of caustic soda (Lye) is added into the Catalyst Premix Tank
3.) Then Methanol is added to the catalyst Pre-Mix Tank
Lye
Funnel Input for caustic soda (lye)
Catalyst Pre-Mix Tank
Methanol
4.) The Solution is them mixed together
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4.) Once the methanol as been added to the catalyst premix tank, you start a mixing process. Mixing the methanol and SVO/WVO. The mixed catalyst premix will be drawn into the manifold at the bottom of the processing tank by the Venturi pump created by the circulation. This will then become a mixture of glycerin and biodiesel solution
Processor Tank
Catalyst Premix
Methanol/Lye Solution
Vegetable Oil
5.) The catalyst mixture is drawn into the processor tank and mixed with the vegetable oil.
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6.) After the mixture is completely mixed, you allow it to settle. At that point, the glycerin will separate from the liquid and forms a dark residue at the bottom of the processor tank. 7.) The glycerin is then drained off via a drainage valve at the bottom of the processor tank. What you have left is biodiesel. Which is then pumped into the wash tank. 6.) The mixed vegetable oil and catalyst is allowed to settle and separate. The top layer will be biodiesel, the bottom layer glycerin Catalyst Pre Mix Tank
Processor Tank
Wash Tank
Biodiesel Biodiesel Glycerin
7.) The Glycerin is drained off.
8.) Water is then introduced and the biodiesel is “washed.”
OK, almost finished... 8.) Washing the biodiesel involves introducing water into the biodiesel mix in order to strain the impurities out of it. Once the biodiesel has been “washed” you usually test it for quality, and you’re ready to go.
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The biodiesel can now the used in any diesel engine. You can use it without fear in cars, trucks, generators, your furnace, anywhere you would normally use diesel fuel. This is not meant as a paint by numbers way to do this. There is more to it than this. (but not much more) This is meant only as an illustration to show you an overview so that you are able to understand the “biodiesel production process” is not for NASA engineers only. Thousands of people, all over the world, are doing it right now. This is a do-able process and you can be on your way to freedom from the high price of energy in a very small amount of time.
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Buy a Biodiesel Processor or Build your Own? This very much depends on your abilities and circumstance. There are advantages and disadvantages to each approach. Let’s look at some of them. Building a biodiesel processor: This option means you are essentially you are going to collect the various parts, then step by step, build your own processor from scratch. Advantages • • •
Cost. Building a processor can cost either much less than a processor or kit, or free. Design: You can design any style, and add options that are exactly right for you and your circumstance Service: Since you built every part, when something goes wrong, you’ll know how to fix it.
Disadvantages • • • • •
Trial and error: Building your own, necessity will require a certain amount of experimentation. Time: Gathering the parts and tools, then the actual building, could require considerable time. Tools: Necessary tools will need to be bought. (Some expensive) Ability: Building your own requires already having the mechanical ability, and basic machine knowledge. Location: You need a good metal workshop, garage, and/or a safe place to work.
Buying a Biodiesel Processor: This option means you’re going to take advantage of another person’s design and building skills. You pay the money, and a finished unit is delivered to your door. Advantages: • • • • •
Time factor eliminated: Fabricated and read-to-go Professional design: Many design problems already worked out. Fabrication tools unnecessary: A prefab unit takes care of that problem Safety factors: Are already thought of, built-in. A very serious consideration if you have children. Sales and service: If good, a real time saver. If bad, a real headache.
Disadvantages: • • •
Cost: A good biodiesel processor can set you back many thousands of dollars Time necessary to recoup cost: Depending on how much money is spent, time factor once processor up and running to recoup investment. Sales and service: Maybe excellent, spotty, or non-existent...you won’t know until it’s needed. (The worst time to find out)
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This is a big decision and deserves serious consideration. At this stage, the wrong decision can make or break your biodiesel experience. My opinion is that: If you are considering building a processor, the ability, tools and workshop are the most necessary. Knowledge can be gained. If you have to buy costly tools, then it may be worth looking into buying a processor, or looking into a kit. The same with the parts: Figure out exactly what you’ll need before hand. (Consult the parts list in this book) and gather as many as possible ahead of time. If you are considering buying a processor, then, of course, cost is going to be the biggest factor. Consider this aspect carefully. My opinion is not to spend more than 1 years cost in petrol-diesel. This is a project that needs to make good financial sense as well. If you’re spending $4,000$5,000 a year (or more) in petrol-diesel costs (not hard to do) then this is might be a good option. If you have a farm, are a trucker, have a fishing boat and/or a small business, then this is probably a no-brainer. Fortunately, there is a third option which can be the best of both worlds…
The Third Option: A Biodiesel Kit The last option is to buy a kit. With a kit, everything has been thought of. The design has been created, the parts collected and categorized, various subcomponents already bought and/or fabricated. Your mission, (Should you choose to accept it ;+) is to assemble these parts into a working processor. This should include a step-by-step, paint-by-the-numbers, manual to go along with it. (Be sure to ask!) Advantages: • • • • • •
Fabrication tools unnecessary. Design already taken take of. Safety factors would/should be built in. Time savings factor of parts collection and fabrication eliminated. Cost of (finished) processor greatly reduced Not necessary to scrounge or buy parts
Disadvantages: • •
Selection of size of processors usually limited. Guarantee, and/or service after the sale, is essential.
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Building a Test-batch Mini-Processor
This test batch mini processor, is exactly that, good for one or two liters test batches. Why would you want to make such small amounts? In order to get your measurements right before you commit to making a full size batch. This is an important step. Getting this right in the beginning can save hours, upon hours of headaches down the road. This is also an excellent little unit to try before investing a lot of money, time, and resources into a project before you know if it is right for you. Spending time, and perfecting your technique at this stage can save you a lot of money.
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Test-Batch Mini-Processor For one or two liters This mini-processor is easy to make from not very much, mostly kitchen stuff and a couple of tools. It’s effective and safe, closed and virtually air-tight, with no splashing or leaking of hot fumes. It will make one- or two-liter batches for test-batch or demonstration purposes, suitable for singlestage or two-stage processes, with full agitation and temperature control. And you can take it anywhere. There’s no need to follow this prescription exactly — use what’s to hand, improvise. For instance, if you don’t have a plastic drill-grip that will fit a plug spanner to use for the drill-stand as described below, we made a second stand using a piece of angle iron and a strip of 3/32" steel half an inch wide bent to fit round the drill and clamped in place with bolts. If you don’t have a welder or can’t make A steel stand, make a stand out of bits of wood bolted together and grip the drill in a portable vice clamped to the vertical. Or something. A crock-pot might do instead of a spaghetti cooker and a portable gas ring. Our gas ring died so now we use a hot-plate instead. You might find a way of using a sealed bearing in the lid rather than a wooden bush. And so on. Let us know!
Materials • • • • • • • • •
Three-liter HDPE container with two lids; Spaghetti-cooker — the bottom and sides of the inner pot are full of holes like a colander; Electric drill; Plastic grip for drill; Stand for the drill; Sparkplug spanner; Stirrer; Portable gas cooker (canned gas) or electric hot-plate; Two half-liter PET bottles.
Cost — in our case, zero: this was all discarded junk, including the drill, and all in perfect working order.
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The drill stand is rigged from scrap angle iron and welded together, but it could just as easily be bolted. The bit that holds the drill consists of the tough plastic grip that came with the drill, a plug spanner, which conveniently fits inside the grip, held in place by two bolts (extra holes mean you can move the drill in and out from the stand), and the plug spanner is welded to an extra bit of angle iron bolted inside the vertical section, again with extra holes above and below for adjustment.
The stirrer is a length of 6mm steel rod with a slot cut in the end and a piece of flat steel brazed into the slot, cut to size so it fits through the larger of the two HDPE container lids. The lid is fitted with a wooden bush cut from hardwood with a 6mm hole drilled through it to take the stirrer shaft. Make it a tight-fitting hole, then heat a piece of the same steel rod as the stirrer and push it carefully through the hole — not too hot, just enough to scorch the surface of the wood inside the hole, not char it. Add a few drops of biodiesel for lubrication. Cut a square hole in the lid the exact size and shape of the bush; cut another hole in the lid insert. Saw two shallow grooves on all four side of the bush, immediately above and below where it will fit the lid. Push the bush into the hole in the lid; push the insert into the lid around the bush. Secure with epoxy resin — push the resin firmly into the grooves to hold the bush in position. Some silicon round the seams helps. Heat up the oil in a saucepan on the gas cooker and pour it into the mini-processor. Slide the business end of the stirrer inside the processor and slide the bush in the lid over the other end; screw the lid on firmly. Fill the two half-litre PET bottles with water at or above the processing temperature. Put the processor into the spaghetti cooker; wedge in position with a PET bottle on either side. Add hot water to the cooker to just below the height of the oil — as
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much water as it will take before the processor begins to float. Use the gas flame to adjust the water temperature to the processing temperature, then turn off the gas.Attach the drill to the stand, tighten the stirrer in the chuck, switch on and start stirring.
Adding the Methoxide We mix methoxide for test batches in HDPE chemical bottles, which have a strong lid and a bung. Drill two holes in a lid and fit two short sections of plastic or 1/8" (4mm) copper piping, fix on both sides with strong epoxy resin. To one, on the inside, fix a length of rigid 1/4 (6mm) plastic tubing that will reach almost to the bottom of the bottle. To the other, on the outside, fit a length of flexible 1/4 plastic tubing. Fit a third section of copper piping to the small lid of the processor. To add the methoxide, remove the lid and bung from the bottle of pre-mixed (cool) methoxide and screw on the transfer lid tightly. Fit the other end of the length of flexible 1/4 plastic tubing to the inlet pipe in the small lid of the processor. Now, carefully, lift the methoxide bottle above the processor and turn it upside down. Air goes into the open pipe to the bottom (now the top) of the bottle, methoxide drains out of the second pipe through the processor lid into the oil to be mixed.
When all the methoxide has drained, turn the bottle right way up and put it down on the table beside the processor. Any stray methanol fumes that don’t condense inside the processor will vent into the methoxide bottle and condense there.
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Monitor the temperature with a thermometer, turning on the heat when necessary — this is quite safe, even with gas, as is running the drill motor, as no methanol fumes escape during processing. The temperature only needs adjustment twice in an hour at normal room temperature.
The HDPE container is translucent rather than fully transparent but it’s clear enough to see the reaction going on inside, and the changing color and viscosity of the oil.
When the process is finished, disconnect the drill, remove the container and stand it on its side to settle, small lid down; later, to drain off the by-product, simply tip it up, hold it over a container and loosen the small lid, tightening again when you hit the yellow biodiesel.
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Buying a Processor Buying a processor is a business decision. The factors you want to weigh of course, are how much is the processor, and how soon will I get my money back and start saving money. As i have said already in this book, a general rule of thumb is spend no more than one year fuel costs. For most people, that will be in the $5000 range. For this price, there are some excellent processors on the market. This doesn’t mean for a second that you can’t find something less expensive that will serve your needs...you can. What I’m trying to say here is in my opinion you want to spend NO MORE than that amount. What to watch out for when buying/building a small scale biodiesel processor: 1. What materials is the machine made from? Stainless steel is the ideal material for the vessels but this will make the machine expensive. Steel is OK. Plastic is NOT acceptable as it becomes unstable at 60 degrees, which is very near the biodiesel reaction temperature, resulting in leaking of joints and potentially complete collapse. It will also become brittle due to attack from the methoxide. The pipe work should NOT have braided flexible plastic on the biodiesel mixer pump. This is something to watch out for as it is a sure indicator that the builders of the machine are incompetent. Accidents have been recorded due to accidental pressure build up in flexible pipework causing an ‘annulism’ and subsequent bursting, spraying hot vegetable, oil possibly containing sodium methoxide, over the operator. 2. What pumps are used? The pump for mixing the biodiesel reactants should be spark proof and this normally requires full ATEX zone 1 certification, not only on the electrics, but also the pump itself. Good quality hand operated pumps are OK. Watch out that the pump will handle particles in the fluid as when making biodiesel it is not normal to filter the veg oil beyond about 2mm. Mag drive pumps are NOT tolerant to particle contamination. Centrifugal is the best option. Most machines have an inadequate mixing pump - many are illegal. 3. Where is the pump mounted and is it self priming? If the pump is not mounted below the level of the bottom of the tank it will need to be a self priming pump. Do not buy machines with pumps mounted half way up the vessel and equipped with priming kits - waste of time! 4. Does the machine have internal heating or is it a separate ‘add on’? The heater should be ATEX rated to zone 0 if it is in the biodiesel reactor and the reactor itself should have automatic fluid level sensors to prevent the following: Many biodiesel processors use immersion heaters located in the reactor and many accidents have been caused by inadvertently turning/leaving the heater element on in an empty reactor that contains methanol fumes. The result is explosions.
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5. Does the machine do all the stages of biodiesel production? These are: Heating, methoxide mixing, biodiesel reaction, water washing, biodiesel drying and filtration. If any of these stages are missing the biodiesel produced WILL damage your engine. 6. Methoxide mixing: NEVER buy a machine that pumps methanol through a container with the catalyst as this produces a dangerous exothermic reaction. Methanol is generally mixed with a conventional vortex mixer, not a pump. The mixer should be flat or domed at the bottom, not conical, as particles of catalyst will become lodged in the cone and will cause malfunction. If, for some reason a pump is used for mixing the methoxide, make sure it is a proper ATEX centrifugal pump rated for grinding particles. NEVER mix methoxide in a open topped vessel as the fumes will harm your health. 7. Buy from a reputable supplier. Things to watch out for here are if they say you can make money out of a small scale biodiesel plant. This is NOT true. Due to various economies in scale, it has been calculated that the minimum size to make a profitable business is 5,000 liters per day. Otherwise, it is always going to be a hobby activity. Do NOT buy from people kindly offering to build you a one off machine. Although their intentions may be good, they are unlikely to have the experience to build a safe machine and will therefore be acting illegally. If you do buy an illegal machine, YOU are not acting illegally unless you ask your mate to come and help you. You are allowed to harm yourself but not your mate. Dont buy an illegal machine. 8. Watch out for false claims made by the seller. One is the profitability as above. Another common sales bluff is to exaggerate the production capability of the machine. The way it is done is to say that biodiesel can be produced in 2 hours, giving 12 batches per 24 hour day. This is completely mis-leading as quality, clean biodiesel cannot be made in less than 24 hours per batch and even this is optimistic. The production from a machine with a reactor capacity of, say 200 liters, is not normally more than 100 liters per day. Be very suspicious of claims more optimistic than this. 9. Look for useful features such as sample points in the reactor and methanol mixing tanks. You need these to test that the process is going to work before mixing the reactants together. Temperature gauges are always useful for peace of mind. 10. Is the unit skid mounted? This is essential if tanks are connected with rigid pipe work as just connecting them on a concrete floor wont be accurate enough to ensure that the joints meet up and don't get strained. If the tanks are not skid mounted they will need to be connected by flexible pipe or by custom onsite built rigid pipe work which are both expensive options and the latter may mean that the machine cannot be moved.
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11. Accidents have happened due to bad biodiesel making process. Don't buy a machine that advocates mixing the methoxide into the hot oil, always do it the other way round. Even if the vessel has a temperature gauge, the oil is generally much hotter at the top than at the bottom. If the oil is over 65 degrees C at the top and you add methanol or methoxide the methanol will boil off, potentially causing a pressure build up and subsequent bursting of the vessel, especially if it is plastic. Then, if you’ve got non-spark proof motors running and a large methanol spillage you’ve got the perfect recipe for a major explosion.
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Buying a Kit In my opinion, a kit makes a lot of sense. Especially for a first-timer. If you are new to biodiesel, this
is an option you should seriously consider.
One, they are way less expensive than a completely built processor. Expect to save anywhere from $500 to $5000. If this is your first time, then a kit makes even more sense. Before buying that $5,000 processor, find out what a processor SHOULD do, needs to do, and what features are important to you. Two, most kits are “Appleseed Processors” meaning they are built around hot water tanks, designed for heating and storing hot liquids. Three, as you build your own processor you learn certain things in the process. You learn what each part is for, and how it fits into the overall process. This knowledge helps you in the making biodiesel process itself. Before Buying a Kit, ask these questions... • • • • • • • • •
Is there a guarantee? How long? What safety features are built into the unit? Is it an open or closed system? (You don’t want an “open” system” ) Do you supply parts as well? What kind of after the sale service can I expect? If I need technical help, can you provide it? Do you supply the necessary chemicals (methanol and lye) as well? What other options are there with this kit? Does a wash tank come with it, or is it extra?
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How to Easily Build a "Down and Dirty" Biodiesel Processor...
...at Home, using easy to find parts, in your Spare Time. For Less Than the Cost of Heating Your Home for One Month in the Winter!
...For Less Than the Cost of One Night Out! Click here for Details
•
How to create a test-batch mini-processor
•
How to make a 5-gallon processor
•
How to build an 80-litre per batch Processor
•
How to Build an “Appleseed” Processor
•
How to build a cone bottom processor
•
How to make a batch reactor
•
How to build 160-liter per day batch processor
•
How to build a 90-litre biodiesel reactor
•
And much more!
Copyright 2008 David Sieg
Click Here for Details...
Making Algae Biodiesel at home
Washing and Quality Testing Biodiesel "At Last! You Can Get Rid Of the Problems of Washing Biodiesel And Quality Testing Without Headaches and Hassles" The No Fluff, No BS Guide to Washing and Quality Testing Biodiesel.
Click here for details Section I: Washing Biodiesel: This is where you'll start by getting a firm foundation to build on. Bubble Washing: How to Build a Wash Tank: Dry Washing Mist Washing Mix Washing: Magnesol: How to Scale Up To Washing Larger Batches: Section II: Emulsion Busting: i.e. "Glop" Glop: Glop Busting on Steroids: Section III: Quality Testing...KNOW, BEFORE you put it into your engine, if your biodiesel is any good. A Simple Quality Wash Test, Visual Inspection, Commercial Quality Testing: ASTM Testing Explained: Clarity Testing: Feedstock Testing Water Testing Cold Weather Testing
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I'm about to Reveal A Simple, Proven System Of Making Biodiesel No One Else Will Tell You About... Making Biodiesel Has Never Been This EasyDiscover How I Taught 100's of People to "Turbo-Charge" Their Plans To Take Control of Their Own Energy Freedom! Even If You Have Never Made Biodiesel Before, Even If You Don't Know A Biodiesel Processor From a Food Processor. This E-book Spills it All! Click here for details You can start Making Biodiesel Anywhere...It doesn't matter where you live. I'm going to empower you with the knowledge to get you up and going, quickly, cheaply, and easily. Here's a secret...it's the PROCESS that is important...NOT the PROCESSOR.
•
• •
•
•
Plan your Making Biodiesel Project with Confidence... Here's the place most people go wrong, but you won't. A complete e-book in itself is devoted to planning. •
• Build a 90 Liter Biodiesel processor with ease... Step-by-step, I take you by the hand and show you, step-by-step how to build your own 90 liter "Appleseed" Processor out of a used Hot Water tank.
Trouble-shoot and solve problems before they arise.. Unlike other books, I know problems are "part and parcel" with any making biodiesel project. I don't gloss over them, instead you get SOLUTIONS. •
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BONUS
Sections
Copyright 2008 David Sieg
Modeling and Simulation of the Algae to Biodiesel Fuel Cycle Honors Undergraduate Thesis Submitted to: The College of Engineering Honors Committee College of Engineering 122 Hitchcock Hall The Ohio State University
By: Nick Sazdanoff Department of Mechanical Engineering Winter 2006
Approved by: ___________________________________ Dr. Yann Guezennec, Adviser Department of Mechanical Engineering
Contents Chapter 1 – Introduction 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Chapter 2 – Literature Review 2.1 The Aquatic Species Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2
2.3
2.1.1
Algae Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.2
Biochemistry and Molecular Biology . . . . . . . . . . . . . . . . . . . . . . 6
2.1.3
Algae Production Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1.4
Microalgae Outdoor Test Facility (OTF) . . . . . . . . . . . . . . . . . . . . 7
Algae Growth in Outdoor Raceway Ponds . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2.1
Microalgae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2.2
Algae Pond Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.2.3
Algae Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Biodiesel Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.3.1
Transesterification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Chapter 3 – Methodology of the GREET Model 3.1
The GREET Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.2
Biodiesel calculations in GREET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
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Chapter 4 – Methodology of the Algae Pond Model (APM) 4.1 NREL Outdoor Test Facility (OTF) Results . . . . . . . . . . . . . . . . . . . . . . . . 28 4.2 APM Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4.2.1
Solar Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.2.2
Day Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.3 Algae Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 4.4 CO2 Sequestration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 4.5 Fertilizer Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.6 Water Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.7 Electricity Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 4.7.1
Paddle Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.7.2
Pumping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.7.3
Centrifuge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.8 Transfer to the GREET Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 4.8.1
Model Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4.8.2
GREET Model Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.8.3
Data Transfer from APM to GREET . . . . . . . . . . . . . . . . . . . . . . 42
Chapter 5 – Modeling and Simulation Results 5.1 Algae Pond Model Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.2 Coronado Power Plant Case Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Chapter 6 – Conclusions and Future Work 6.1 Algae Pond Model (APM) Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . 56
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6.2 Algae Biodiesel as an Alternative Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Bibliography
58
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List of Figures 1.1 Petroleum Forecast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.1 Schematic of microalgae OTF facility in Roswell, NM . . . . . . . . . . . . . . . . . . . . . . 8 2.2 Scaled model of a 1,000 m2 algae pond . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.3 Scaled model of large algae farm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.4 Comparative evaluation of harvesting processes . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.5 Inputs and outputs of transesterification reaction . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.1 Energy efficiencies of petroleum based fuel cycle stages . . . . . . . . . . . . . . . . . . . . 20 4.1 Average solar radiation in the U.S. for the month of July . . . . . . . . . . . . . . . . . . . . 29 4.2 Solar radiation curve fit for Roswell NM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 4.3 Average day length for Roswell NM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 4.4 Calibration of algae growth to solar radiation for Roswell NM . . . . . . . . . . . . . . . 33 4.5 Calibration of CO2 consumption and algae growth . . . . . . . . . . . . . . . . . . . . . . . . . 34 4.6 Picture and technical specifications of the Alfa Laval CH-36B nozzle type centrifuge used in the APM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 4.7 Schematic of algae to biodiesel fuel cycle depicting which steps are modeled using the APM and which are modeled using GREET . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 4.8 Algae to biodiesel modifications to default GREET model . . . . . . . . . . . . . . . . . . 42
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4.9 Default GREET model biodiesel worksheet with algae to biodiesel modification cells highlighted in yellow and APM input cells in red . . . . . . . . . . . . . . . . . . . . . . 43 5.1 Location of algae simulation sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5.2 Daily solar radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 5.3 Daily algae productivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 5.4 Daily fertilizer usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 5.5 Daily CO2 consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 5.6 Daily electricity usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 5.7 Size and location of 73 million gallon per year algae to biodiesel facility near Coronado power plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5.8 Well to wheel energy use of algae to biodiesel B20 fuel cycle compared to lowsulfur diesel fuel cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 5.9 Well to wheel emissions of algae to biodiesel B20 fuel cycle compared to low-sulfur diesel fuel cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 5.10 Well to wheel urban emissions of algae to biodiesel B20 fuel cycle compared to low-sulfur diesel fuel cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
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List of Tables 1.1 Production averages from common oil seed crops . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.6 Long term OTF results from 1,000 m2 raceways . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.1 U.S. soybean production and deposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.2 Usage intensity fertilizer, energy, and pesticides for soybean farms . . . . . . . . . . . . 25 3.3 Input and output of soybean oil extraction plants . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3.4 Input and output of biodiesel plants with transesterification process . . . . . . . . . . . 27 4.1 Long term OTF results from 1,000 m2 raceways . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 4.2 Average monthly solar radiation in Roswell NM . . . . . . . . . . . . . . . . . . . . . . . . . . 30 4.3 Electricity consumption of a 1,000 m2 algae pond . . . . . . . . . . . . . . . . . . . . . . . . . 36 5.1 Location and solar radiation data for perspective algae to biodiesel sites . . . . . . . . 44 5.2 Production results using APM for inputs given in table 5.1 and for the soybean to biodiesel fuel cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.3 Number of ponds and production levels supported by Coronado Plant . . . . . . . . . . 52 6.1 Comparison of OTF results to laboratory results . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
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Chapter 1 Introduction 1.1 Motivation Transportation is the lynch pin of our society, powering the economies of the world everyday. Petroleum based fuels account for 97% of transportation energy, without petroleum food and products could not be shipped from place to place, people could not drive to work, and the world as we know it will no longer exist. At our staggering consumption levels the worlds petroleum reserves will be exhausted in the next 30 to 40 years. To compound this problem the existing petroleum powered transportation network is responsible for a large amount of the hazardous emissions causing global warming and air pollution problems worldwide. A viable energy source that eliminates petroleum and reduces green house gas emissions must be found. In 2004 the United States consumed over 7.5 billon barrels of oil and 24% of this was in the form of diesel fuel, which is the driving force behind the trucking and shipping industry (U.S. Energy Information Administration EIA). In the U.S. last year these activities resulted in the consumption of over 64 billion gallons of diesel fuel. At these staggering consumption rates, which increase every year, the limited world petroleum
1
reserves are only expected to last another 30 years according to the United States Energy Information Administration (EIA). Figure 1.1 displayed below shows the dramatic drop off in petroleum supply that is forecast in the year 2030.
Figure 1.1: Petroleum forecast
Many experts around the world feel that this is a very generous assumption. For example Dr. Seppo Korpela a professor in mechanical engineering at Ohio State University has extensively studied the phenomena of peak oil and he claims that we will reach peak oil production within the next 10 years. Everyday hazardous emissions are dumped into the atmosphere, 25% of green house gases in the United States result from the transportation sector (EIA). These emissions are causing worldwide global warming and air pollution problems. Smog that fills cities around the world is generated from the cars and trucks that swarm the streets.
2
These are becoming major problems in the U.S. and the world, with the transportation industry being one of the main contributors to these problems. An alternative form of energy that reduces petroleum consumption and cuts down on hazardous emissions must emerge to power the transportation network. There are many organizations and companies are searching for viable alternatives. To compare these various alternatives Argonne National Labs created the Green house gases Regulated Emissions and Energy use in Transportation (GREET) model. The GREET model analyzes the well-to-wheel energy use and emissions resulting from the various fuel cycles and compares them to the current petroleum fuel cycle. After extensively analyzing GREET model results I decided to conduct a more in depth study of biodiesel. Biodiesel is a proven technology and a very attractive alternative fuel source. It can be made from any fat or vegetable oil, currently the majority of biodiesel produced in the U.S. comes from soybeans. This current system provides an energy benefit of 35% meaning that you are left with 35% more energy then is put into the system. It provides a substantial reduction in green house gases, and can be used in current diesel vehicles with minor modifications. The major drawback of biodiesel is that only 42 gallons of biodiesel are produced on an acre of farm land. Even if all of the soybeans grown in the U.S. were used for biodiesel production, it would be well short of or current diesel consumption. A new higher yielding source of biodiesel must be discovered in order to justify biodiesel the source to power our transportation needs. Microalgae are remarkably efficient biological factories capable of taking a waste (zero-energy) form of carbon (CO2) and converting it into natural oil. Microalgae have
3
been found to have incredible production levels compared to other oil seed crops like soybeans. Table 1.1 below shows a comparison of oil yield for various oilseed crops. Production Averages for Common Oil Crops Plant lb. oil/acre Gallons of biodiesel/acre Algae 6,757 700 Coconut 2,070 285 Jatropha 1,460 201 Rapeseed 915 126 Peanut 815 112 Sunflower 720 99 Soybean 450 62
Table 1.1: Production averages for common oil crops
Extensive research has been carried out to develop high rate algae growth systems capable of producing biodiesel on a large scale. The United States Department of Energy (DOE) carried out an 18 year study of biodiesel production from algae, and this study is discussed in detail in Chapter 2. For my honors research project I developed a model that predicts the production levels as well as the energy use and emissions of the algae farms placed at various locations throughout the United States. The following chapters discuss in detail the research that I conducted on the algae to biodiesel fuel cycle and the GREET model. Chapter 4 describes the Algae Pond Model and how it was created. The results obtained from modeling the algae to biodiesel fuel cycle are discussed in chapter 5, and conclusions and recommendations are given in Chapter 6.
4
Chapter 2
Literature Review 2.1 The Aquatic Species Program This chapter analyzes each step of the algae to biodiesel process, and begins with a review of previous algae to biodiesel studies. From 1978 to 1996, the United States Department of Energy’s Office of Fuels Development funded the Aquatic Species Program (ASP). The focus of the program was to develop renewable transportation fuels from algae. Extensive research was conducted on the production of biodiesel from algae grown in large raceway ponds that use waste CO2 from coal fired power plants as a fertilizer for the algae. The main highlights of the program are described in the following sections.
2.1.1 Algae Classification The study began by trying to determine which species of algae would be suitable for the purpose of developing transportation fuels. For the production of biodiesel the selected strain of algae must have very high growth rates and a very high lipid or oil
5
content. There are well over 100,000 different species of algae, so the scientists involved in the study had the daunting task of analyzing these species and determining which were most suitable for producing biodiesel. By the end of the study the researchers had identified around 300 strains of algae that are the most suitable for producing biodiesel. They all have high growth rates, oil content, and are capable of growing in harsh climates. These strains of algae are currently housed at the University of Hawaii, and are available to interested researchers (Benemann, 1996).
2.1.2 Biochemistry and Molecular Biology Next researchers focused their efforts on using biochemistry to manipulate the algae to have higher oil content. The goal of this research was to take advantage of the “lipid trigger”, which is the phenomenon that occurs when microalgae are under environmental stress many species go through a metamorphosis and begin producing very large amounts of oil (Benemann, 1996). Researchers thought that this could be done by denying the algae certain nutrients, specifically nitrogen. However in the end the researchers concluded that although the nitrogen deficiency did increase the oil content of the algae it does not lead to increased oil productivity because it reduces the growth rates of the algae. During this time researchers were also attempting to genetically modify the certain algae species so that they would produce more oil and also enable them to grow in very harsh environments. Although the researchers did make significant discoveries they were unable to demonstrate increased oil production in the cells. Researchers concluded
6
that for future endeavors strains of algae should be selected that are native to the region where commercial microalgae production sites are planned. 2.1.3 Algae Production Systems Over the course of the program several test sites were constructed to examine the feasibility of large scale algae production in open ponds. Many different algae growth systems have been studied, for example the Japanese government have developed optical fiber based reactor systems that could dramatically reduce the amount of surface area required for algae production. However while breakthroughs in these types of systems have occurred their costs are prohibitive, especially for the production of fuels. The ASP focused on open pond raceway systems because of their relative low cost (Benemann, 1996). The Algae Pond Model, which is a program developed in Matlab to predict the energy use and emissions that result from growing algae in various regions, is based off of the results obtain during the operation of the Microalgae Outdoor Test Facility (OTF) in Roswell, New Mexico.
2.1.4 Microalgae Outdoor Test Facility (OTF) In 1987 construction began on an algae growth facility consisting of two 1,000m2 ponds, one plastic lined and another unlined, and six small, 3m2 ponds. An abandon water research facility in Roswell New Mexico was the site chosen for this operation. Roswell receives large amounts of daily solar radiation and has abundant flat desert land with large supplies of saline groundwater, making it an excellent location for algae growth. One limitation of the site was the low nightly temperatures, which turned out to be to low for many of the more productive species identified.
7
Building the large system required installation of two water pipeline of 1,300m in length. The ponds were 14 x 77 m, with concrete block walls and a central wooden divider. The paddle wheels were approximately 5m wide, with a sump that allowed counter flow injection of CO2. One pond was plastic lined; the other had a crushed rock layer, and the walls were cinder block (Benemann, 1996). Figure 2.1 below shows an overview of the layout of the facility.
Figure 2.1: Schematic of microalgae OTF facility in Roswell, New Mexico
The OTF facility experimented with three different species of algae; first they used C. cryptica CYCLO1. C. cryptica had high productivities in the summer months but reaching 30 g/m2/d but fell off drastically during when the weather became colder. Next M. minutum (MONOR2) a more cold-tolerant organism was used. Even though productivity in the winter was very low 3.5 g/m2/d in December the algae survived despite the ponds freezing over multiple times. Next Amphora sp. was used and although it exhibited growth rates above 40 g/m2/d in the summer it also could not survive in the 8
winter months. Because of its survivability M. minutum was selected as the most suitable strain of algae for the Roswell location (Goebel, 1989). The OTF facility operated the large scale ponds for two years, by the end of the study they had determined some important parameters for future algae ponds: 1) Power for pond mixing is quiet low around 0.1 kW/1,000m2 pond. 2) Pond mixing should be in the 15-25 cm/s range, and pond depth 15-25 cm. 3) CO2 utilization efficiencies of near 90% overall should be achievable. 4) Large-scale pond productivities of 70 mt/ha/yr are realistic goals for this process. 5) The small-scale ponds can be used to screen strains and optimize conditions. The results from the OTF large scale ponds are shown in table 2.1 below; the APM is based off of these results.
Pond Liner YES NO NO YES NO
CO2 use (m2/d) 15.2 13.4 14.6 22.0 19.2
Dates 10/1/88 - 9/30/89 10/1/88 - 9/30/89 10/1/89 - 9/30/90 6/1/90 - 10/30/90 5/1/90 - 9/30/90
Productivity Carbon Use Water Loss 2 (gm afdw/m /d) Efficiency (mm/d) 9.8 59 5.7 8.3 50 6.2 10.5 82 19 81 18 88
Table 2.1: Long Term OTF Results from 1,000 square meter Raceways Notes: gm/afdw/m2/d: grams of ash-free dry mass per square meter per day Pond liner: YES indicates a plastic lined pond; NO indicated dirt bottom
2.2 Algae Growth in Outdoor Raceway Ponds This section is a step by step walk through of the algae to biodiesel process. The size of the algae ponds are 1,000m2 the same size studied in the OTF. All of the processes discussed in this section are modeled in the Algae Pond Model. First the algae
9
pond operations are analyzed, followed by the oil extraction process, and finally transesterification or biodiesel production.
2.2.1 Microalgae Micro algae are remarkably efficient biological factories capable of taking a waste (zero-energy) form of carbon (CO2) and converting it into a high density liquid form of energy (natural oil). The four most abundant classes of micro algae are diatoms (Bacillariophyceae), green algae (Chlorophyceae), blue-green algae (Cyanophyceae), and golden algae (Chrysophyceae). Diatoms were the only class of micro algae analyzed in this study. They are found in fresh and salt water, and they store carbon in the form of natural oils or as a polymer of carbohydrates. (Benemann, 1996) For the algae to biodiesel cycle to be successful a species of algae that has high growth rates and oil content must be used. The Aquatic Species Program recommends that an effort be made to naturally select strains at the locations that would likely be commercial micro algal production sites. In this manner, the algae would be exposed to the prevailing environmental conditions, particularly the indigenous waters. If a nonnative strain of algae is used it is likely that a native species will infiltrate the pond and over time dominate the pond, killing off the desired strain. The Algae Pond Model is based off of the results obtained at the OTF using a unicellular green algae called Monoraphidium minutum (M. minutum). Algae reproduce by cellular division. They divide and divide and divide until they fill whatever space they are in or exhaust their nutrients (Tickell, 2003). There are multiple stages of algae growth that depend on the culture volume and algae density.
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Assume there is a small batch of algae is placed into a large volume tank mixing tank, and that the tank is supplied with enough CO2 and sunlight to generate maximum growth. Some form of agitation, such as shaking or mixing is necessary to ensure nutrient and gaseous exchange. The algae will initially enter an exponential growth phase, where cells grow and divide as an exponential function of time, as long as mineral substrates and light energy are saturated (Richmond, 2003). When the concentration of algae is high enough that light does not penetrate through the entire culture, the algae move into the light limited linear growth phase, which is expressed by the following equation (Richmond, 2003).
IA = u * X * V / Y I = Photon flux density (h J m^-2)^-1 A = Illuminated surface area (m^2) u = Specific growth rate (1 h^-1) X = Biomass concentration (grams/liter) V = Culture volume (m^3) Y = Growth yield (g/J) Finally if the size of the tank is not increased the algae will eventually reach a terminal density and stop growing. Algae growing in a flowing pond or raceway will operate in the light limited linear growth stage. The exponential growth stage is not achievable, since the algae are not all subject to the necessary amount of solar radiation. As algae cycle around the race way pond a certain percentage of algae will be harvest leaving the remaining algae room to grow in the linear growth range. Maintaining the algae in the linear growth range has allowed the model of algae growth to be controlled by linear relationships
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2.2.2 Algae Pond Operations A scaled version of the 1,000m2 algae pond is shown in figure 2.2 below.
77 m
Algae harvesting to settling ponds
CO2 bubblers from coal fired electric plant
14 m
Water and nutrient inlet Paddle wheel
Figure 2.2: Scaled model of a 1,000 m2 algae pond
This is the pond that the APM is modeled after. The pond depth is 20 cm corresponding to a volume of 200 m3 or 200,000 liters, it is unlined and powered entirely by electricity. Many ponds of this size would be fit into a small area along with larger settling ponds and a pumping centrifuge station in order to produce algae on a large scale. Figure 2.3 below is a scaled layout of what one of these facilities might look like.
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Centrifuge and pumping station Algae storage Settling Ponds (2 total)
Raceway ponds (64 total)
650 m
190 m
Figure 2.3: Scaled model of large algae farm for production of biodiesel
Algae pond operations are very simple. The algae are introduced into the pond and allowed to grow until they occupy 1% of the volume of the pond. Very high growth rates are achieved because the pond is constantly mixed by the paddle wheel and it is infused with an ample amount of CO2 and fertilizer. The paddle wheel rotates providing a current of 20 cm/s around the pond. The mixing is required to ensure that all of the algae receive the necessary amounts of solar radiation, CO2, and fertilizer required for optimal growth. The CO2 is injected into the algae pond in the form of flume gas from a nearby coal fired electric plant. The bubblers are spaced around the pond so that the CO2 is evenly dispersed throughout the pond. A 1,000 m2 algae pond operating in Roswell New Mexico consumes around 10,589 kg of CO2 each year. This is a miniscule amount
13
considering that the average 785 MW power plant produces 19,488 tons of CO2 daily, or enough to support about 330,000 algae ponds (CleartheAir, 2000). Algae require a certain amount of phosphorus and nitrogen to grow at optimal rates. The phosphorus and nitrogen are pumped into the ponds along with ground water from the central pumping station shown in figure 2.3. The nitrogen is in the form of ammonia or nitrate and must compose 0.8% of the volume of the pond solution to ensure maximum algae production. Likewise phosphorus is in the form of phosphate and must compose 0.6% of the pond (Benemann, 2006). In the future both of these nutrients could be supplied in the form of municipal solid waste. Water must also be continuously supplied to the ponds because a certain amount is lost daily due to evaporation and farm operations. The OTF tests recorded an average water loss of 6.2 mm or 6.2 m3 of water per day. This must be replaced with saline or fresh ground water depending on the species of algae used.
2.2.3 Algae Harvesting Algae harvesting is one of the major factors that must be overcome in order for algae to be used as a fuel source. The problem is that microalgae mass cultures are dilute, typically less than 500 mg/l on a dry weight organic basis, and the cells are very small. Many unicellular species like M. minitum are around 5 micrometers in diameter. In order to be processed into biodiesel the algae must be in the form of a paste that is 15% solids. In the raceway ponds the mixture is about 1% solids, this mixture must go through a process which will result in a concentration of at least 15%.
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Many different algae harvesting processes have been studied figure 2.4 below shows a number of these processes which were studied by Dr. John Benemann in 1996.
Figure 2.4: Comparative evaluation of harvesting processes
Centrifugation – The algae pond solution is pumped into a large centrifuge, which rotates at several thousand RPM causing the algae to be pressed against the outer wall, which is a filter only a few microns in spacing. The water is forced out, while the algae remain of the screen in the form of a paste about 20% algae. This is a proven method that has been extensively used when working with microalgae. Studies have determined that a nozzle disc type centrifuge with intermittent discharge is the best option for algae 15
harvesting (Mohn, 1988). The downfall however is the high power requirements or high cost associated with operating the centrifuge. Chemical flocculation – Certain chemicals like lime, alum, or chitosan can be added to the algae pond solution causing charge neutralization of the algae. This results in the algae clumping together. There is also a very high cost associated with this method, because of the large amounts of chemicals that are required. The APM uses settling ponds as the initial harvesting method, which will bring the solution to 3% algae. From the settling ponds this mixture will be put through a centrifuge which will bring the mixture to 15% algae. Using the settling ponds will help to reduce energy consumption and cost of centrifuge operations.
2.3 Biodiesel Production In order to be converted into a liquid fuel the oil contained in the algae must be extracted. According to Nick Nagle a senior engineer at the NREL who was a vital part of the ASP, algae oil extraction is very similar to soybean oil extraction, and can be modeled the same. The oil is extracted by mixing Hexane, a chemical made from petroleum, with the algae paste. The hexane removes the oil from the algae, this mixture of hexane and oil is distilled leaving pure algae oil. The remaining hexane is recycled through another batch of algae. The algae fiber remaining after this process can be used as fertilizer for the algae farms.
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2.3.2 Transesterification Transesterification is the process that the algae oil must go through to become biodiesel. It is a simple chemical reaction requiring only four steps and two chemicals. 1. Mix methanol and sodium hydroxide creates sodium methoxide 2. Mix sodium methoxide into algae oil 3. Allow to settle for about 8 hours 4. Drain glycerin and filter biodiesel to 5 microns Figure 2.5 below shows the inputs and outputs of this process.
Figure 2.5: Inputs and outputs of transesterification reaction
The alcohol used in this reaction can be either methanol or ethanol, the catalyst is sodium hydroxide, and the oil is any fat or vegetable oil. The outputs are 86% Methyl Esters or biodiesel, 9% Glycerine which can be used to make soap and other products, 1% fertilizer, and 4% alcohol which can be recycled back through the process (Tickell, 2003).
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Chapter 3 Methodology of the (GREET) Model 3.1 The GREET Model The Green house gases Regulated Emissions and Energy use in Transportation (GREET) model was created by Argonne National Laboratory. The model follows the entire fuel cycle path for over thirty different fuels. It breaks the fuel cycle up into upstream production and distribution of the fuel (well to pump) and downstream vehicle usage (pump to wheel). The GREET model displays energy use and emissions produced from different fuel cycle paths. This report will show the equations used to obtain the values for energy use and emissions as well as the assumptions that were made to insert values into these equations. The GREET model starts off by analyzing six petroleum-based fuel cycles: petroleum to conventional gasoline (CG), reformulated gasoline (RFG), conventional diesel (CD) (low-sulfur content), reformulated diesel (RFD), liquid petroleum gas (LPG), and electricity via residual oil. The upstream analysis of these fuels goes through three stages: recovery, refining, and distribution. For a given upstream stage, energy input per unit of energy product output is calculated by using the energy efficiency of the stage.
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By definition, energy efficiency is the energy output divided by the energy input (including energy in both process fuels and energy feedstock). Thus total energy input is: Energyin = 1/efficiency Energyin = Energy input of a given stage (say, in Btu per Btu of energy product output from the stage) Efficiency = Energy efficiency for the given stage (defined as [energy output]/[energy input] for the stage).
All of the assumed efficiencies are listed on the INPUT page of the GREET model. These efficiency values come from previous studies and research at Argonne National Laboratory. The table below shows the efficiencies used for petroleum fuel cycle stages.
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Figure 3.1: Energy efficiencies of petroleum based fuel cycle stages (%)
Upstage emissions of VOCs, CO, NOx, PM10, SOx, CH4, N2O, and CO2 for a particular stage are calculated in grams per million Btu of fuel throughput from the stage. Emissions from combustion of process fuels for a particular stage are calculated by using the following formula: EMcm,i
= (∑ j
∑ EF
i , j ,k
* EC j , k ) /1, 000, 000
k
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EMcm,i = Combustion emissions of pollutant i in g/ 106 Btu of fuel throughput EFi,j,k = Emission factor of pollutant i for process fuel j with combustion
technology k (g/ 106 Btu of fuel burned) ECj,k = Consumption of process fuel j with combustion technology k (Btu/ 106 Btu
of fuel throughput) ECj,k = EC * Sharefuelj * Sharetechk,j EC = Total energy consumption for the given stage (in Btu/ 106 Btu of fuel
throughput) Sharefuelj = Share of process fuel j out of all process fuels consumed during the
stage
∑
j
fuel j = 1
Sharetechk,j = Share of combustion technology k out of all combustion
technologines for fuel j ( ∑ k techk , j = 1 )
Combustion technology shares (Sharetechk,j) for a given process fuel are influenced by technology performance, technology costs, and emission regulations for stationary sources. In GREET, default technology shares are assumed for each upstream stage. In most cases, for a given combustion technology, GREET has two sets of emission factors: current and future. Emission factors of combustion technologies by fuel type are presented on the EF page of GREET 1.5a. Emission factors (EFi,j,k) for , CO, NOx, PM10, CH4, and N2O for different combustion technologies fueled by different process fuels are primarily derived from the fifth edition of EPA’s AP-42 document (EPA 1995). In the GREET model, SOx emission factors for combustion technologies fueled with all fuels except coal, crude oil, and residual oil are calculated by assuming that all sulfer contained in these process fuels is converted into sulfur dioxide (SO2). The following formula is used to calculate the SOx emissions of combustion technologies:
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SO xj = Density j ÷ LHV j × 1,000,000 × S _ ratio j × 64 ÷ 32
SOxj = SOx (primarily SO2) emission factor for combustion of process fuel j (in g/106 Btu of fuel j burned); Densityj = Density of process fuel j (in grams per gallon [g/gal] for liquid fuels, grams per standard cubic foot [g/scf] for gaseous fuels, or grams per ton [g/ton] for solid fuels) LHVj = Low heating value of process fuel j (in Btu/gal for liquid fuels, Btu/scf for gaseous fuels, and Btu/ton for solid fuels) S_ratioj = Sulfur ratio by weight for process fuel j 64 = Molecular weight of SO2 32 = Molecular weight of elemental sulfur Uncontrolled SOx emission factors associated with combustion of residual oil, crude oil, and coal are very high. For these cases, SOx emission factors for various combustion technologies are derived from the fifth edition of EPA’s AP-42 document. In GREET combustion CO2 emission factors in g/106 Btu of fuel throughput are calculated by using a carbon balance approach. Through the approach, the carbon contained in a process fuel burned minus the carbon contained in combustion emissions of VOCs, CO, and CH4 is assumed to convert to CO2. The following formula is used to calculate CO2 emissions: CO2, j ,k = [ Density j ÷ LHV j × 1,000,000 × C _ ratio j − (VOC j ,k × 0.85 + CO j ,k × 0.43 + CH 4, j ,k × 0.75)] × 44 ÷ 12
CO2,j,k = Combusion CO2 emission factor for combustion technology k burning process fuel j (in g/106 Btu of fuel j burned) Densityj = Density of process fuel j (in g/gal for liquid fuels, g/scf for gaseous fuels, or g/ton for solid fuels
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LHVj = Low heating value of process fuel j (in Btu/gal for liquid fuels, Btu/scf for gaseous fuels, and Btu/ton for solid fuels) C_ratioj = Carbon ratio by weight for process fuel j VOCj,k = VOC emission factor for combustion technology k burning process fuel j (in g/106 Btu of fuel j burned) 0.85 = Estimated average carbon ratio by weight for VOC combustion emissions COj,k = CO emission factor for combustion technology k burning process fuel j (in g/106 Btu of fuel j burned) 0.43 = Carbon ratio by weight for CO CH4,j,k = CH4 emission factor for combustion technology k burning process fuel j (in g/106 Btu of fuel j burned) 0.75 = Carbon ratio for CH4 44 = Molecular weight of CO2 12 = Molecular weight of elemental carbon The above formula shows the calculation method for combustion CO2 emissions by which carbon contained in VOC, CO and CH4 is subtracted. On the other hand, VOCs and CO reside in the atmosphere for less than 10 days before they decay into CO2. In GREET 1.5, the indirect CO2 emissions from VOCs and CO decay in the atmosphere are considered.
3.2 Biodiesel Calculations in GREET The GREET model does an excellent job of estimating the energy use and emissions that result from the soybean to biodiesel fuel cycle. The model is very complete, analyzing the inputs and outputs for each step of the process. This section is a breakdown of the default biodiesel calculations in GREET.
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First the GREET makes assumptions for the amount of soybeans yielded per unit area, the oil content of these soybeans, and their uses. This data was obtained from actual statistics presented by the Food and Agricultural Policy Research Institute, and the results are shown in table 3.1 below.
Table 3.1: U.S. Soybean production and deposition
Next the GREET model analyzes soybean farming, and assumes an energy consumption of 32,104 Btu/bushel. Table 3.2 below shows the usage intensity of fertilizer, energy, and pesticides for soybean farming. The values shown in table 3.2 come from a study done by John Sheehan at the NREL in 1998.
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Table 3.2: Usage intensity of fertilizer, energy, and pesticide for soybean farming
This study analyzed the fertilizer, energy, and pesticides for soybean farming in the 14 main soybean producing states. Because these values are for 1990 they were reduced by 10% to the approximate values for 2005 used in GREET. The soybean oil extraction process is analyzed next. At soybean oil extraction plants, soybeans are crushed and then organic solvents are used to extract the oil. The solvent extraction process is a widely used and well established technology. The standard solvent in n-hexane produced from petroleum, and most of this is recovered and recycled through the process several times. In calculating emissions and energy use nhexane is assumed to be produced from crude, and its upstream production energy use 25
and emissions are adopted from energy use and emissions calculated for producing liquid petroleum gas. Steam is also used in the oil extraction process and is assumed to be generated from natural gas. The inputs and outputs of the soybean oil extraction process are shown in table 3.3 below.
Table 3.3: Inputs and outputs of soybean oil extraction plants
Next the transesterification process is modeled. This data again comes from studies done by John Sheehan and Ahmed from the National Soy Diesel Development Board. Table 3.4 shows the results from the transesterification process.
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Table 3.4: Inputs and outputs of biodiesel plants with the transesterification process
The GREET model also considers the energy and emissions that result from transporting the various materials through each step in the process. Each of these processes are then combined resulting in the energy use and emissions produced by the soybean to biodiesel fuel cycle.
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Chapter 4 Methodology of the Algae Pond Model 4.1 NREL Outdoor Test Facility Results The algae model is based off of the results obtained by NREL at the Outdoor Test Facility (OTF) ponds in Roswell, New Mexico. A description of the facility as well an explanation of why NREL chose this area is given in chapter 2. This site was in operation for three years and the results from the OTF facility are given in table 4.1 below. These results where used extensively in modeling algae farm operations.
Pond Liner YES NO NO YES NO
CO2 use (m3/d) 15.2 13.4 14.6 22.0 19.2
Dates 10/1/88 - 9/30/89 10/1/88 - 9/30/89 10/1/89 - 9/30/90 6/1/90 - 10/30/90 5/1/90 - 9/30/90
Productivity Carbon Use Water Loss (gm afdw/m2/d) Efficiency (mm/d) 9.8 59 5.7 8.3 50 6.2 10.5 82 19 81 18 88
Table 4.1: Long Term OTF Results from 1,000 square meter Raceways Notes: gm/afdw/m2/d: grams of ash-free dry mass per square meter per day Pond liner: YES indicates a plastic lined pond; NO indicated dirt bottom
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4.2 APM Inputs 4.2.1 Solar Radiation
To model the amount of UV radiation that an algae pond receives solar radiation data was obtained from the National Renewable Energy Laboratory (NREL) Resource Assessment Program (http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/). This site provides maps that display the average solar radiation that an area receives per month. Figure 4.1 is the solar radiation map for the United States for the month of July; the green dot is the location of Roswell, New Mexico.
Figure 4.1 – Average solar radiation in the U.S. for the month of July
29
The solar radiation for each month of the year was determined and can be seen in table 4.2 below. Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Average 2 kWh/m /d 4 5 6 7 8 8.5 8 7 6 5 4 3 5.9167 Table 4.2: Average Monthly Solar Radiation in Roswell, New Mexico
This solar radiation data was plotted against time and a sine wave was fit to the data as shown in the figure below.
Figure 4.2: Solar Radiation Curve Fit for Roswell, New Mexico
The corresponding equation for solar radiation in Roswell NM is
UV = 2.75 × sin(π /180 × days − π / 2) + 5.75 UV = Solar radiation (kWh/m2/day) days = number of days (360 days make up one year in simulation)
30
A sine wave describing the amount of solar radiation that an area receives can be generated using the maximum and minimum values of solar radiation. In the United States the maximum radiation is in June and the minimum is in December. Given these two inputs the solar radiation curve can be determined by the following formula:
UV = A × cos(π /180 × days ) + avgUV UV = Solar radiation (kWh/m2/day) days = number of days (360 days make up one year in simulation) A = (max – min)/2 or (UV_Jun – UV_Dec)/2 avgUV = (max + min)/2 or (UV_Jun + UV_Dec)/2
4.2.2 Day Length
The next step in the modeling process is to generate a function of average hours of daylight for a given area for each day of the year. This is vital information because the algae pond should only be operated during daylight hours, because without sunlight the algae do not grow and therefore the operation of the paddle wheel and pumps is a waste of energy. The model prompts the user to input the average hours of daylight the area receives on December 21 and June 22 the shortest and longest days of the year. The generation of the day light function is done using these values and creating a cosine wave, the same procedure as generating the solar radiation function. The figure below shows the hours of daylight received each day in Roswell New Mexico.
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Figure 4.3: Average day length for Roswell New Mexico
4.3 Algae Growth The micro algae are grown in 1,000 m2 ponds, which are circulated by a paddle wheel as described in Chapter 2. When grown in this manner the algae are in the light limiting linear growth phase described by the equation
IA = u * X *V / Y I = Photon flux density (h J m^-2)^-1 A = Illuminated surface area (m^2) u = Specific growth rate (1 h^-1) X = Biomass concentration (grams/liter) V = Culture volume (m^3) Y = Growth yield (g/J)
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The major factor effecting algae growth is solar radiation, therefore the modeling of algae growth is based on a calibration between solar radiation and algae growth. The results for algae growth from the OTF operations were calibrated against the amount of solar radiation the area received during that time period to obtain a formula for algae growth based on the amount of solar radiation the pond receives. Figure 4.4 below shows the calibration plot and the corresponding equation relating solar radiation to algae growth. In the equation y is algae growth (g/m2/d) and x is solar radiation (kWh/m2/d).
Algae Growth (g/m^2/d)
20 18
y = 3.7618x - 11.162 16 14 12 10 8 5
5.5
6
6.5
7
7.5
8
Solar Radiation (kWh/m^2/day)
Figure 4.4: Calibration of Algae Growth to Solar Radiation for Roswell NM
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4.4 CO2 Sequestration The amount of CO2 sequestered by the algae is a vital part of the algae to biodiesel process. It is the main feedstock for the algae, providing a reduction in the amount of CO2 injected into the atmosphere from the coal fired electric plants. The amount of CO2 consumed was determined from the experimental results achieved in the OTF shown in table 4.1 above. The measured CO2 consumption was calibrated against the recorded algae growth rate as shown in figure 4.5 below.
18
CO2 Usage (m^3/d)
17
y = 0.6565x + 5.0784
16 15 14 13 12 11 10 8
10
12
14
16
18
20
Algae Growth (g/m^2/d) Figure 4.5: Calibration of CO2 Usage and Algae Growth
A straight line curve fit resulted in the following equation:
CO2consumed = 0.6565 × AlgeaGrowth + 5.0784 CO2consumed = Amount of CO2 consumed by the pond per day (cubic meters) AlgaeGrowth = Amount of new algae growth per day (g)
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However because this process is only 80% efficient the equation must be modified in order to ensure that the algae receive the required amount of CO2 to achieve maximum growth. The equation used in the Algae Pond Model is:
CO2consumed = (0.6565 × AlgaeGrowth + 5.0784) / 0.8
4.5 Fertilizer Consumption There are two elements that must be used to fertilize the algae, they are nitrogen and phosphorous. Nitrogen can be added to the ponds in the form of ammonia or nitrate, and should be mixed at 0.8% of the dry weight of the algae in the pond. Phosphorous as phosphate should be mixed at 0.6% of the dry weight (Benemann, 2006). The percentage of each element required by the algae ponds was given to me by Dr. John Benemann, who was one of the lead scientists on the Aquatic Species Program and has extensive experience and expertise in the field. The Algae Pond Model multiples these percentage by the amount of daily growth, to determine the amount of Nitrogen and Phosphorous required by the pond.
4.6 Water Consumption The OTF ponds recorded an average water loss of 6.2 mm or 6.2 cubic meters of water per day due to evaporation. Although this is not a constant daily value in reality, the Algae Pond Model will assume a daily water loss of 6.2 cubic meters. The evaporation rate is a function of solar radiation, temperature, wind velocity over the pond 35
surface, and current velocity of the pond. These are variables that should be considered by the Algae Pond Model in the future in order to properly model the amount of water required by the ponds.
4.7 Electricity Use 4.7.1 Paddle Wheel
Electricity is the major energy source used to power algae farm operations. The amount of power required for paddle wheel, pumping and centrifuge operations where determined from previous studies and current equipment specs, and are given in table 4.3 below. Average Average Daily Power Yearly Power Percentage of Consumption Consumption Algae Farm Operation (kWh) (kWh) Operations Paddle Wheel 1.23 441.2 17% Pumping 2.01 722.7 27% Centrifuge 4.11 1480.6 56% Total 7.35 2644.5 Table 4.3: Electricity Consumption of 1,000 m2 algae pond
The amount of power required by the paddle wheel was determined during OTF operations to be 0.1 kW (Benemann, 1996). This value is then multiplied by the number of hours of operation per day giving a certain number of kilowatt hours of electricity used per day. The hours of operation correspond to the hours of daylight because as long as there is solar radiation the algae are growing and the pond must be in operation.
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4.7.2 Pumping
Water will be pumped to and from the ponds using a Marlow Pumps Self-priming Centrifugal Pump model: 4B-PEL. This pump was selected because it is capable of effectively pumping water containing algae up to 5% by volume. This pump is rated to move 550 gal/min of algae sludge up to 15 feet vertical displacement at 15 horsepower, or one kilowatt hour will pump 11.4 cubic meters of algae water. To determine how much power is required to operate the pond, the amount of water to be pumped must be known. The amount of water to be pumped will be the amount of water pumped from the raceway pond to the settling pond, plus the amount of recycled water pumped from the settling pond back to the raceway pond, and the amount of fresh water that must be pumped due to evaporation. The amount of water pumped into the settling pond is a function of algae growth rate corresponding to the equation:
SettlingPond = % Pond × A lg aeGrowth SettlingPond = Amount of water pumped from raceway to settling pond (m3) %Pond = Constant equal to (10/10.5) or average amount of raceway pumped per day (5% by vol. or 10 m3) divided by the average growth (kg/day) AlgaeGrowth = (kg) of daily algae growth The amount of recycled water pumped from the settling pond back to the raceways is given by the equation:
SettlingPond _ recycled = SettlingPond × % SettlingPond SettlingPond_recycled = Water pumped from settling pond to raceway (m3) %SettlingPond = Constant equal to 67% or volume of settling pond recycled
37
These two values are combined with the amount of water that results from evaporation resulting in the total volume of water being pumped per day as shown in the equation:
TotalDailyPumping = SettlingPond _ recycled + SettlingPond + evaporation TotalDailyPumping = (m3) Amount of water pumped per day The amount of power required to for pumping is then determined by dividing the amount of water pumped per day by the rated power of the Marlow Pump model 4B-PEL.
DailyPumpingPower = TotalDailyPumping / Pump _ power DailyPumpingPower = (kWh) Amount of power required to operate pumps Pump_power = Constant (11.4 m3 / 1 kWh) from pump specs
4.7.3 Centrifuge
The Algae Pond Model’s centrifuge calculations are based on the operation of the Alfa Laval CH-36B GOF Separator Nozzle centrifuge, a picture of this device along with its technical specifications is shown in figure 4.6 below.
ALFA LAVAL CH-36B GOF Separator Nozzle Centrifuge Technical specifications Max. throughput capacity Max. nozzle flow Max. rotation Max. G-force Feed temperature range Installed motor power Noise level (ISO 3744 or 3746)
225 m3/h 160 m3/h 2900 rpm 4300 G 0-100 °C 190/225 kW 85 dB
Figure 4.6: Picture and Technical Specifications of the Alfa Laval CH-36B nozzle type centrifuge used in the Algae Pond Model
38
This centrifuge was recommended by Dr. Nick Nagle with the NREL, who worked on the Aquatic Species Program and has had extensive experience with the mass culture and harvesting of microalgae (Personal communication). The amount of power consumed by the centrifuge is found using the equation:
CentrifugePower = SettlingPond × 33% ÷ CentThru × CentPower CentrifugePower = (kWh) Amount of power required by centrifuge corresponding to daily algae growth SettlingPond = Amount of water pumped from raceway to settling pond (m3) 33% = Amount of mixture from settling pond that goes thru the centrifuge CentThru = Constant 180 (m3/hr) CentPower = Constant 225 (kW) The amount of algae water put through the centrifuge was determined to be 180 m3/hr which is 80% of the rated max throughput capacity. The centrifuge cannot operate at the maximum throughput capacity, because the algae water entering the centrifuge is 3% algae and the particles are very small in size (Alga Laval spec sheet). The power consumption of the various algae pond operations are summed resulting in the energy or electricity usage for the pond, this value is plotted so the user can see the amount of daily electricity required for pond operations.
4.8 Transfer to GREET Model 4.8.1 Model Separation
The outputs of the Algae Pond Model (APM) need to be inserted into the GREET model along with a few modifications in order to analyze the energy use and emissions of
39
the entire fuel cycle. The APM models the algae farm operations up to harvesting and storage of dry algae mass. The dry algae mass then goes through the oil extraction process, which is a batch process very similar to the soybean oil extraction process. It was determined that the soybean oil extraction model in GREET can be used to model algae oil extraction (Personal conversation Nagle). Therefore the GREET model is used to analyze the algae to biodiesel fuel cycle from oil extraction to vehicle use. Figure 4.7 below shows a schematic of the algae to biodiesel process, depicting which steps of the process are modeled using the APM and which are modeled in GREET.
Coal fired electric plant Settling Pond CO2
Algae Pond Model
H2O
Centrifuge Algae Pond Water
Fertilizer
SUN
Algae
Storage Tanks
Paddle wheel
Oil extraction Alga e
Use as fertilizer
Oil & Solve Distillatio
Biodiesel Oil
Biodiesel Production
Hexane
Glycerin
Hexane
OIL
GREET Model Natural Gas
Methanol
KOH Potassium hydroxide
Figure 4.7: Schematic of Algae to Biodiesel Fuel Cycle depicting which steps are modeled using the APM and which are modeled using GREET
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4.8.2 GREET Model Modifications
Several need to be made to the default GREET model in order to accurately model the algae to biodiesel process as appose to the soybean to biodiesel process. The GREET model should be run for long term results INPUT sheet cell B3, all of the other changes will be made on the biodiesel BD worksheet in the GREET model. First the shares of process fuels must be adjusted because soybean farming uses diesel fuel, gasoline and electricity whereas algae farm operations only use electricity. Therefore zeros need to be entered into cells B43 B44 and B47, while 100% needs to be entered into cell B48. Next, algae have higher oil content then soybeans, which results in the production of more biodiesel per bushel. The GREET model uses a default value of 5.7 pounds of soybeans to produce 1 pound of oil, however the algae species used in the model requires only 5 pounds of algae to produce 1 pound of oil. Therefore cell C11 must be changed from 5.7 to 5. The amount of fertilizers and pesticides must also be adjusted. Nitrogen used cell C38 must be changed from 107.1 to 217.4 grams/bushel. Phosphorus used cell D38 must be changed from 335.7 to 163.1 grams/bushel. Potassium, herbicide, and pesticide cells E38, F38, and G38 all need to be changed to zero. With these modifications made the GREET model is now ready to accept inputs from the APM and accurately model the algae to biodiesel cycle. Figure 4.8 below lists the changes that need to be made to the GREET model in order to model the algae to biodiesel process.
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Algae to biodiesel modifications to default GREET All changes made in biodiesel sheet (BD) Enter zeros in cells B43 B44 and B47 Enter 100% in cell B48 Change C11 from 5.7 to 5 Change C38 from 107.1 to 217.4 Change D38 from 335.7 to 163.1 Enter zeros into cells E38, F38, and G38 Figure 4.8: Algae to biodiesel modification to default GREET Model
4.8.3 Data Transfer from APM to GREET
The APM outputs the amount of energy (Btu) required to produce one bushel or 60 pounds of ash free dry algae mass in the Matlab command window. This value is determined by dividing the total amount of energy used for the year by the number of bushels produced. The user must enter this value into the GREET model sheet BD cell B38 replacing the default soybean farming input of 28,926 Btu/bushel. Next the APM outputs the amount of CO2 sequestered or used by the algae pond. This value needs to be subtracted from the GREET value for CO2 usage. The user must enter the CO2 emissions cell B79 by clicking on it once, then the amount of CO2 sequestered in the APM needs to be subtracted from the entire default GREET formula. The input cells that must be changed are highlighted in red in figure 4.8 below. By making this adjustment the GREET model will now determine the energy use and emissions that result from algae pond operations as well as for the entire fuel cycle.
42
Figure 4.9: Default GREET Model biodiesel worksheet with algae to biodiesel modification cells highlighted in yellow and APM input cells highlighted in red
43
Chapter 5 Modeling and Simulation Results 5.1 Algae Pond Model Results This chapter examines the results from running the Algae Pond Model for three suitable locations for algae operations. These locations were chosen because each of the areas receives large daily amount of solar radiation, and they all have mild winters ensuring year long operation. There is a coal fired electric plant and barren land at each of the sites providing the necessary resources for algae pond operations. Table 5.1 below shows the location, solar radiation, and hours of daylight for the selected sites. This information was input into the APM.
Power Plant Hours of Hours of Average UV Average UV Location daylight Dec. 21 daylight Jun. 22 radiation in Dec. radiation in Jun.
Rodemacher Boyce, LA
10.1
14.2
3
7.5
Escalante Roswell, NM
10
14.4
3
8.5
Coronado St. Johns, AZ
10
14.3
3.5
9.5
Table 5.1: Location and solar radiation data for perspective algae to biodiesel sites
44
Figure 5.1 below shows the location of each of the simulation sites. The green stars represent the site locations, the Rodemacher plant in Boyce, LA is given by the abbreviation LA, the Escalante plant in Roswell, NM is given by NM and the Coronado plant is given by the abbreviation AZ.
AZ
NM LA
Figure 5.1: Location of algae simulation sites, the green stars mark location of sites
After the values from table 5.1 are input into the APM in MatLab, the program cycles through the operations described in Chapter 4 Methodology of Algae Pond Model, and creates the following outputs. The APM outputs 5 figures, the first is the amount of daily solar radiation that impacts the area for each day of the year beginning on January 1st, as shown in figure 5.2 below. It is evident in figure 5.2 that the Coronado site in Arizona receives the most solar radiation per day, this will correlate to faster algae growth, and higher biodiesel
45
production per unit area then the other sites.
Figure 5.2: Daily solar radiation
Next the APM generates a plot showing the daily algae productivity, and as expected the Arizona location (AZ) has the highest daily productivity. Figure 5.3 is the plot of algae productivity per day. The daily productivity will directly impact the amount of fertilizer, CO2, and electricity consumed per day.
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Figure 5.3: Daily algae productivity
Figure 5.4 displays a plot showing the fertilizer usage per day at each location. The amount of fertilizer used is directly related to algae growth, because fertilizer like CO2 is the feedstock for the algae, and therefore higher algae growth rates result in higher consumption of nutrients, or fertilizer and CO2.
47
Figure 5.4: Daily fertilizer usage
Next the APM outputs the amount of CO2 sequestered or consumed daily by the algae pond. This is vital when trying to determine the size of operation or the number of algae ponds that can be sustained at a given location. A coal fired electric plant produces a set number of tons of CO2 daily, this number divided by the maximum amount of CO2 sequestered by a single pond gives the number of ponds that can be sustained by the coal fired electric plant. Figure 5.5 below shows the amount of CO2 sequestered daily at the given locations, with the maximum amount sequestered occurring when algae growth is at its maximum around the end of June.
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Figure 5.5: Daily CO2 consumption
Figure 5.6 displays the daily electricity requirements of the pond. Again the Arizona location has the highest energy needs because the higher algae growth rates require more algae water to be pumped from the raceway ponds to the settling ponds, and longer centrifuge operation. The maximum daily electricity required is 15 kWh per day for the algae pond in Arizona.
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Figure 5.6: Daily electricity usage
In the MatLab command window the APM outputs the amount of biodiesel produced annually at each location, the energy required to produce one bushel (60 lbs) of algae, and the amount of CO2 sequestered per bushel. These values are then input into the GREET model as described in section 4.8.2. Table 5.2 below displays these results for the three simulation locations and for the soybean to biodiesel cycle. It can be seen in Table 5.2 that the Coronado site in St. Johns, AZ produces the most biodiesel annually and also gives the greatest energy benefit for the algae to biodiesel cycle, which means that it produces 10% more energy then is input into the system. Although all of the simulation sites provide an energy benefit they are all substantially lower then the benefit from the soybean to biodiesel cycle. However using soybeans to produce biodiesel yields much less biodiesel per unit area compared to the algae to biodiesel cycle. At the
50
Arizona location fourteen times the amount of biodiesel is produced per unit area compared to using soybeans in the Midwest. GREET Inputs Energy required to CO2 Sequestered produce one bushel of (g/bushel) algae (Btu/bushel)
Gallons of Biodiesel Produced per year
Energy benefit
Rodemacher Boyce, LA
145
6%
68587
83605
Escalante Roswell, NM
177
8%
65195
76466
Coronado St. Johns, AZ
225
10%
61811
69526
Soybeans Midwest
16
35%
28926
0
Location
Table 5.2: Production Results using Algae Pond Model for Inputs given in Table 5.1 and for the soybean to biodiesel cycle
5.2 Coronado Power Plant Case Study This section will discuss the full fuel cycle analysis of a proposed alga to biodiesel facility in St. Johns, Arizona near the Coronado Power Plant. As shown in section 5.1 a 1,000 m2 algae pond in St. Johns, Arizona would produce 225 gallons of biodiesel per year. This is by far the highest yield of any of the test cases, and for this reason has been selected to simulate the development of a large scale alga to biodiesel facility at this location. The Coronado Power Plant produces has a generating capacity of 785 MW of power, and it produces 19,488 tons of CO2 daily (CleartheAir, 2000). The maximum daily CO2 consumption per pond is 54,000 grams per day. As shown in Table 5.3 below 51
the maximum number of algae ponds that can be supported by the Coronado Plant is 327,399, corresponding to a land area requirement of 245 square miles. This data is shown in Table 5.3 below. CO2 released Max CO2 Max number of Coronado Plant daily Coronado consumption per ponds Total land generating Power Plant 1000 m^2 pond supported by area (mi^2) capacity (MW) (tons) (g/day) Coronado Plant 785
19,488
54,000
327,399
245
Annual biodiesel production (gal) 73,664,840
Table 5.3: Number of ponds and production levels supported by Coronado Power Plant
To put this into perspective the Coronado Plant produces 0.2 % of the total electricity generated from coal each year according to the United States Energy Information Administration (EIA), and 73 million gallons of biodiesel represents 0.12% of diesel fuel consumption in the United States. Figure 5.7 shows the size and location of the proposed facility.
- Indicates an algae farm that is 20 miles long and 13 miles wide
Figure 5.7: Size and location of 73 million gallon algae to biodiesel facility near Coronado plant
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Using the GREET model the well to wheel energy use and emissions resulting from producing biodiesel at the Coronado facility were determined. Figure 5.8 is a well to wheel energy use comparison between the biodiesel produced at the Coronado facility and conventional low-sulfur diesel. The biodiesel produced at from the algae is mixed with petroleum diesel to form B20, 20% biodiesel and 80% petroleum diesel. This was chosen because it is an industry standard and the GREET model is setup to analyze B20.
Total Energy 1
Fossil Fuels Petroleum
-20.0%
-15.0%
-10.0%
-5.0%
0.0%
5.0%
10.0%
15.0%
% compared to Low-Sulfer Diesel cycle
Figure 5.8: Well to wheel energy use of algae to B20 cycle compared to low sulfur diesel cycle
It is evident from figure 5.8 that the algae to biodiesel cycle requires about 11% more energy then the low-sulfur diesel cycle. This is because an extensive amount of energy required for algae farm operations. The conventional diesel cycle requires far less energy upstream because the operation is very simple. The oil is pumped out of the ground, refined, and distributed. However the algae to B20 fuel cycle provides an 18% reduction
53
in petroleum consumption, which is the number one criterion that an alternative fuel must meet. The alga to biodiesel fuel cycle provides a substantial reduction in green house gas emissions but increases the emissions of other pollutants. Figure 5.9 is a well to wheel emissions comparison between the biodiesel produced at the Coronado facility and conventional low-sulfur diesel.
GHGs CO2 CH4 N2O VOC: Total CO: Total NOx: Total PM10: Total SOx: Total
1
-60.0%
-40.0%
-20.0%
0.0%
20.0%
40.0%
60.0%
80.0%
100.0% 120.0% 140.0%
% Compared to Low-Sulfur Diesel cycle
Figure 5.9: Well to wheel emissions from algae to B20 cycle compared to low sulfur diesel cycle
The algae to biodiesel fuel cycle provides a 40% reduction in green house gases because the algae sequester large amount of CO2 in the raceway ponds. However acid rain and smog forming emissions of nitrous oxides NOx and sulfur oxides SOx are increased by over 30%. This is a result of the coal burned to produce electricity to power the algae
54
farm operations. These hazardous emissions are emitted at the coal fired electric plants away from cities and the majority of the population. The algae to biodiesel fuel cycle reduces urban emissions because biodiesel burns cleaner then conventional diesel. Figure 5.10 is a well to wheel urban emissions comparison between the biodiesel produced at the Coronado facility and conventional low-sulfur diesel.
VOC: Urban 1
NOx: Urban PM10: Urban SOx: Urban
-5.0%
-4.0%
-3.0%
-2.0%
-1.0%
0.0%
% Compared to Low-Sulfer Diesel cycle
Figure 5.10: Well to wheel urban emissions from algae to biodiesel fuel cycle compared to low sulfur diesel cycle
This slight reduction in emissions is a result of using B20 compared to using low-sulfur diesel in conventional vehicles.
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Chapter 6 Conclusions and Recommendations 6.1 Algae Pond Model (APM) future work There are a few modifications that need to be made to the APM in the future so that it provides better results using a more diverse range of inputs. The current version of the APM does not include a temperature input, and therefore can only model locations that do not encounter freezing temperatures. Knowing the temperature at a potential site is required to determine if the algae ponds will freeze during any time of the year. If the ponds freeze the algae will die and production will stop. In the future a temperature function should be built into the APM to more accurately determine production levels, and expand the possible input locations. The fertilizer consumption modeled by the APM also needs reworked. Currently the amount of fertilizer used is based off of the amount of water being cycled through the ponds. This is not accurate because large amounts of water are lost due to evaporation while the fertilizer remains in the system. A new fertilizer model based on micro algae nutrient consumption needs to be developed.
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6.2 Algae biodiesel as an alternative fuel It was shown in the introduction of this report that a new energy source, which eliminates the use of petroleum and reduces green house gas emissions must arise if we are to continue our way of life. The use of biodiesel produced from algae was extensively studied and although this fuel cycle does provide substantial reductions in petroleum use and emissions several obstacles must be overcome for algae biodiesel to be an attractive alternative fuel. First algae harvesting methods must be refined to use less energy. The current methods that involve a centrifuge require too much energy resulting in a 12% increase in total energy required compared to the low-sulfur diesel cycle and only a 10% energy benefit. This also produces very high operating costs making it an unattractive investment. Second, strains of algae that have higher growth rates and are more resistant to adverse conditions need to be found or created. Although algae produce much higher yields of biodiesel per unit of land compared to any other oil seed crop these production levels can still be dramatically increased. Table 6.1 below shows the amount of biodiesel that is produced per acre at the OTF facility, and although this is almost an order of magnitude higher then the soybean to biodiesel cycle, if laboratory growth rates of 30 g/m2/day could be obtained using algae that are 50% oil instead of 20% almost 7000 gallons of biodiesel could be produced annually on an acre of land. If biodiesel could be produced at these staggering production levels this would be a very economically attractive alternative.
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Algae OTF Laboratory
Annual amount of Growth rate % Oil of algae by biodiesel produced per (g/m^2/day) weight acre (gal) 8.3 20% 700 30 50% 6694 Table 6.1: Comparison of OTF results to laboratory results
If these two processes were solved and biodiesel was produced from algae on a large scale, automobile manufactures would need to convert their diesel vehicles to run on B100 or pure biodiesel. If these developments occur biodiesel produced from algae could one day power the transportation network of the future.
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Bibliography AHMED, I.; ET AL.: How Much Energy Does It Take to Make a Gallon of Soy Diesel? National Soy Diesel Development Board, 1994 BENEMANN, J.; DUNAHAY, T.; ROESSLER, P.; SHEEHAN, J.: A Look Back at the U.S. Department of Energy’s Aquatic Species Program – Biodiesel from Algae. U.S. Department of Energy’s Office of Fuels Development, 1998 BENEMANN, J.; OSWALD, P.I.: Systems and Economic Analysis of Microalgae Ponds for Conversion of CO2 to Biomass. Department of Energy Pittsburgh Energy Technology Center, 1996 BENEMANN, J.: Personal conversation about algae growth and harvesting. January 17 2006 GOEBEL, R.P.; TILLETT, D.T.; WEISSMAN, J.C.: Design and operation of an outdoor microalgae test facility. Final Report to the Solar Energy Research Institute, 1989 MARTINI, N. AND SCHELL, J.: Plant Oils as Fuels Present State of Science and Future Developments. Berlin ; New York : Springer, c1998 MOHN, R.H.: Harvesting of Micro-algal Biomass. Microalgal Biotechnology, Cambirdge U. Press, 1988
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NAGLE, N.; LEMKE, P.: Mircoalgal Fuel Production Processes: Analysis of Lipid Extraction and Conversion Methods. Solar Energy Research Institute, 1989 NAGLE, N.: Personal conversation regarding algae harvesting recommended using settling ponds and nozzle type centrifuge, also said that oil extraction of soybeans is very similar and can be used for modeling purposes. January 2006 RICHMOND, A.: Handbook of Microalgal Culture Biotechnology and Applied Phycology. Blackwell Publishing, 2003 TICKELL, J.: From the Fryer to the Fuel Tank the Complete Guide to Using Vegetable Oil as an Alternative Fuel. Tickel Energy Consultants, 2003 WANG, M.: GREET 1.5 – Transportation Fuel-Cycle Model Volume 1: Methodology, Development, Use, and Results. Center for Transportation Research, Energy Systems Division, Argonne National Laboratory, 1999
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