mervenvs Posted November 26, 2008 Report Share Posted November 26, 2008 I've been interested for a while in the use of algae as biofuel (see algae fuel in wikipedia), but this is not what I want to talk about here.One of the reason algae have high potential is their tremendously fast growth compared to other plants.So could it be possible to get char from algae ? Instead of/in addition to using algae as fuel, it might be worth using them as a source of biochar since:- they grow fast- they are happy in sunny conditions, which correlates with conditions where Biochar as soil amendment seems the most effective.- they can be used with dirty/grey water (even seawater for seaweed, but with slower growth, I think) The problems I see are:- the fact that you need a lot of nutrients to speed the growth of algae. Although these are usually recycled when algae are used for biofuels, I don't know what a high content of NPK would lead upon pyrolysis.- you obviously need a lot of water, which prevent the use in arid conditions, unless you use grey water (could that be a form of waste treatment ?), you are close to the coast, or you use a closed system. I wonder if a low-tech system would be feasible, the type you could use in a garden. I am not sure if it would be interesting on the large industrial scale though, since making biofuel will probably be more valuable, but I would find particularly exciting to see algae from the Greenfuel system (ESU) used as pre-char for soil amendment ! What do you think ? I haven't seen any thread dedicated to the home-growth of algae. Is any of you interested in algae as fuel/carbon trap ? Quote Link to comment Share on other sites More sharing options...
Essay Posted November 26, 2008 Report Share Posted November 26, 2008 Yes, yes, & yes!!! ...and not just grey water, but humanure, pig farm tailing, etc. Extract the bio-oils as a part of the drying process and then carbonize.They're working on high-oil algaes. I think I recall 8,000 gallons of bio-oil/acre. ...be back later....~ ;) Quote Link to comment Share on other sites More sharing options...
Michaelangelica Posted November 26, 2008 Report Share Posted November 26, 2008 AgreedAlgae has a lot of potential as bio-fuel and charcoal. I read recently of a W.A. Australian farmer sowing his salty irrigation ditches with sea-weed Sorry google seems to be slowing up and I can't find the URL What do you know- a little creativity in searching and found this :-WA Wheatbelt tries seaweed as cash crop. 11/01/2007. ABC News Online There is a lot more to this story. Quote Link to comment Share on other sites More sharing options...
mervenvs Posted November 26, 2008 Author Report Share Posted November 26, 2008 Extract the bio-oils as a part of the drying process and then carbonizemmm, I read that up to 60 % of the algae is oil, i'm not sure if the rest is very valuable, but a good comprise would be indeed to extract the oil and then carbonize ! back after work with more data ! Quote Link to comment Share on other sites More sharing options...
mervenvs Posted November 27, 2008 Author Report Share Posted November 27, 2008 I think I recall 8,000 gallons of bio-oil/acre. Wikipedia gives [5000-20,000] gallons/acre/year, quoting the article on biofuels. The problem is that this article gives a value of ~300 gallons/acre/year. Greenfuel indicates a maximum value of 5500 gal/a/y.Considering the fact that GF use a closed photobioreactor and fed them with a stream of quite concentrated CO2, which are probably close to optimum conditions for algae growth, I doubt a value of 20,000 can be commonly reachable. Quote Link to comment Share on other sites More sharing options...
Essay Posted November 29, 2008 Report Share Posted November 29, 2008 I don't know if the distinction between bio-oils and biofuels is important here, but I'm pretty sure only a fraction of bio-oils can be used for biofuels. So maybe 5000 gal. biofuel is equivalent to 8000 gal. bio-oils. But whatever.... It's a lot better than the 400-1200 gallons of ethanol that they get from corn! And done properly, it can be carbon negative--whereas corn is lucky to be carbon neutral or only moderately carbon positive. This could be a huge new industry in the near future....They could sell carbon credits to the polluters.... ~ :) Quote Link to comment Share on other sites More sharing options...
Ahmabeliever Posted November 30, 2008 Report Share Posted November 30, 2008 You can crop algae every week. I do, I feed it to fish. It doesn't take much pollution to grow algae, if you fed a portion of humanure to a pond system you'd have an extremely efficient biomass producer, no need for added co2 there's plenty free with the outgassing. You could use agricultural slurry in exactly the same way. Then there's all the food processing and brewers wastes... Microbiology, imo, will be our saving grace. I'm just experimenting now with EM to see if I can make algae go away (well, be of numbers where it's not taking over the ecosystem). Cross your fingers and wish me luck, our lakes need a break. Quote Link to comment Share on other sites More sharing options...
Michaelangelica Posted November 30, 2008 Report Share Posted November 30, 2008 You can crop algae every week. I do, I feed it to fish. It doesn't take much pollution to grow algae, if you fed a portion of humanure to a pond system you'd have an extremely efficient biomass .How do you do this?Can the algae be used on the garden as Mulch? Microbiology, imo, will be our saving grace.IMO2(See "wee beasties" thread) Quote Link to comment Share on other sites More sharing options...
mervenvs Posted December 1, 2008 Author Report Share Posted December 1, 2008 You can crop algae every week. I do, I feed it to fish.How do you grow your algae ? In a pond ? How do you harvest ? Do you dry them as well ?I'm just experimenting now with EM to see if I can make algae go away (well, be of numbers where it's not taking over the ecosystem). Cross your fingers and wish me luck, our lakes need a break.What is EM ? Quote Link to comment Share on other sites More sharing options...
Ahmabeliever Posted December 3, 2008 Report Share Posted December 3, 2008 What is EM? - Essential Microbes - Made in Japan by Dr Higa EM now belongs to a trust and is distributed at cost only in the countries it is produced. Ti find em in NZ I type in emnz dot com. For australia try emau. EM is a symbiotic community of microbes that enhance each other via exudates and other processes. Together they are greater than the sum of parts. ActinomycetesRay fungiPhotosynthetic bacteriaYeastsLactic Acid Bacteria How do I grow algae - In a half a barrel filled with water that gets a flow from an aquaponic system. This is the sump of the system. Water flows 15 minutes every two hours during daylight. No flow at night. Will grow every 2 days if I let it get full light I've got it covered at present as it is housing some guppies for breeding. Can the algae be used as mulch? Well.... I feed it to worms, and to fish... It makes a 'cake' if thrown directly on the ground but would get eaten/broken down eventually. Good thinking though, I'm always running out of mulch myself. I have found shredded paper works good but you have to shred it fine (like with a machine) or snails live in it. I can dry algae in one day left in the sun, squeeze out the excess water and lay flat. I generally just feed it wet, but keep a few cakes handy for friends to give to their fish. It's a hot fishy favourite. To get this algae just get some duckweed. The algae are associated. Then get the water too rich for duckweed the algae will begin to take over. I grow duckweed outside now it's summer, in the shade (a couple hours sun). This doesn't get taken over by algae. Hope that lot helped. Algae outgrows everything I've seen. Quote Link to comment Share on other sites More sharing options...
mervenvs Posted December 8, 2008 Author Report Share Posted December 8, 2008 Wow ! that sounds impressive. i tried to grow algae in half-cut plastic bottles, and the harvest after many weeks was... shamefully small. I didn't seed or anything, just took some water from the river added some NPK and soil.Do you know how much you get by harvest ? I wonder what the dimensions of your barrels are. Maybe UK is too cold as well, and not sunny enough ! Quote Link to comment Share on other sites More sharing options...
froggy Posted December 9, 2008 Report Share Posted December 9, 2008 Hey people, After reading some of the past postings, I can see I have alot of work ahead of me. Algae has been far too hyped and far too little actual data is ever brought to the discussion table. Yes algae looks like it grows fast and it does grow fast in the right environment, those conditions are very hard to replicate on an industrial scale. The world of commercial algae is virtually 100% in open ponds because the value of the product cannot support advanced infrastructure, such as a PBR. In todays marketplace, $4-9/lb dried weight is where the market is. At 20% lipid content, that puts biodiesel at a cost of ~ $200/gallon and no one is producing a consistant 20% lipid content algae because of various technical issues that we could get into later. By the way, Dr Briggs and other that quoted 20,000 gal/acre as a theoretical limit has its uses but dont missunderstand these numbers. Mike is quoting a theoretical limit that is unavailable with the biology and technology that exists. And the most important part of this number is that its a gross estimate, not a net estimate. A net estimate would need to include production costs, specifically EROI value which will significantly lower those real world numbers. Meaning 5000gal/ac turns into 1000gal/ac net gallons for sale. One more item, if you think you are going to be able to adjust the temp of the medium so one can grow algae in the northern climes of the world, its because you havnt done the simple Delta heating calculations of trying to grow algae in a water medium. Unless you have free heating source, you cant period. Algae is ~ 50% carbon by weight. Depending on how you plan to turn algae into char, there are a few technical issues ahead of you. Frankly, Im not sure anyone has successfully field trialed a way to turn algae into a biochar, tho I know of at least 1 benchtop models that exist. Moral of the story is that I dont think growing commercial algae is a viable option for fuel or charcoal but harvesting free, nasty shoreline washup into terra preta and harvesting the NPK so that it doesnt fall back into the system for next years algae bloom is available under the right technologial and economic conditions. Froggy Quote Link to comment Share on other sites More sharing options...
Essay Posted December 10, 2008 Report Share Posted December 10, 2008 Hey people,...those conditions are very hard to replicate on an industrial scale. The world of commercial algae is virtually 100% in open ponds...Froggy ?? Hiya Froggy! Welcome! Algae seems like a very workable and natural solution (with lots of potential for selective diversification and genetic modification, i.e. domestication). Also it is not only a solution for CO2 problems, but simultaneously tackles food, fuel, economic and social issues, multiplying its payoff factor over simply as a biofuel. Today @ Colorado State UniversityCurrently, algae grown in photo-bioreactors at Solix headquarters yield more than five times the amount of fuel per acre of land per year than agriculture-based fuels including ethanol from corn and biodiesel from soy and canola, at their current commercial yields. Solix engineers have created systems that automatically adjust for environmental changes such as sunlight and temperature to optimize growing conditions. Algae cultivation consumes substantial quantities of carbon dioxide, potentially helping to reduce emissions of greenhouse gases believed to contribute to global climate change. The Solix system has the ability to capture emissions directly from power plants and factories. The biofuel plant will be located on a ten-acre site on the Southern Ute Indian Reservation in Southwest Colorado. It will be built in two phases, with the first to be completed in 12 to 18 months and consisting of four acres of photo-bioreactors for growing algae, and one acre for a lab facility. Upon completion of the first phase, Solix will build an additional five-acre expansion that will allow the pilot facility to produce at commercial scale. "As the world moves to replace fossil fuels with the clean, renewable energy of the future, we see algae as a highly attractive alternative to agricultural crop feedstocks," said Doug Henston, CEO of Solix. ===EMBARGOED FOR RELEASE OoopsThe program's attempts to grow algae on an agricultural scale encountered two fundamental problems, however. The first was that the open ponds in which the high-lipid-concentration species of algae were grown were quickly colonized by local indigenous algae that had much lower levels of lipids. The second problem was that the costs of regulating temperature in the open ponds was inordinately expensive. The bioreactor designed by Jim Sears, founder of Solix Biofuels Inc., solves both of those problems. The algae grow within closed plastic bags, which reduces the possibility of infestation drastically. And a novel low-energy temperature control system keeps the algae within a temperature range that optimizes growth. Because of the low capital costs of the bioreactor design, and the fact that the CO2 can be sourced from biomass-fed electricity plants rather than only coal or natural gas, it presents opportunities for developing countries also."This is an ideal solution for producing liquid transportation fuels while absorbing greenhouse gas emissions through growing biomass in countries that don't have access to fossil oil or coal," Sears said. Colorado State University - News & Information"This process harnesses photosynthesis to turn carbon dioxide and energy captured from the sun into an economical petroleum substitute." "Algae are the fastest growing organisms on the planet, and can produce 100 times more oil per acre than conventional soil-tilled crops that are now being grown for biofuel use," said Solix founder Jim Sears. Solix officials estimate that widespread construction of its photo-bioreactor system could meet the demand for the U.S. consumption of diesel fuel - about 4 million barrels a day - by growing algae on less than 0.5 percent of the U.S. land area, which is otherwise unused land adjacent to power plants and ethanol plants. The plants produce excess carbon dioxide, which is necessary to turn algae into oil. In addition to producing biodiesel, the process would prevent a large portion of the greenhouse gases produced by coal-burning power plants from being expelled directly into the atmosphere. These are the guys who are talking about 8000 gals/acre/yr. ...though I think they mean bio-oil, not refined fuel. ...and then of course there is the "char" potential, though it sounds as if they have other ideas (feedstock, ?). Here is a very polished slide show (w/ a slide showing algal "fuel" at 1000 gal/acre "today," and 5000 gal/acre "tomorrow") comparing algae with other biofuel crops.http://ncvecs.colostate.edu/cac.docs/cac23/PDFs/Sheehan.pdf=== ...andThe Competitive EdgeBoosting the amount of power from renewable resources would lead to more jobs, higher wages, and an increased gross domestic product for Colorado, reports the Environment Colorado Research and Policy Center in a report issued in February, 2007. According to the report, increasing the renewable energy standard through 2020 also would: Increase Colorado’s share of gross domestic product by a net of $1.9 billion. Supplement landowner income with cumulative total lease payments of $50 million. Save 18 billion gallons of water that otherwise would be used for steam and cooling in coal- or gas-fired plants. Reduce soot, smog, mercury, and global warming pollution by 11 percent. Provide 10 times more local tax revenue than coal-fired power plants. But I'd sure like to see those links you mentioned... on the other thread, "Algae." ~ :evil: Quote Link to comment Share on other sites More sharing options...
Essay Posted December 10, 2008 Report Share Posted December 10, 2008 ...field trialed a way to turn algae into a biochar, tho I know of at least 1 benchtop models that exist. Moral of the story is that I dont think growing commercial algae is a viable option for fuel or charcoal but harvesting free, nasty shoreline washup into terra preta and harvesting the NPK so that it doesnt fall back into the system for next years algae bloom is available under the right technologial and economic conditions. FroggyI'd like to hear more about the one benchtop model.... B) ;) I kept wondering what the Chinese were doing with all that seaweed they scooped out of the bay, before the Olympics--wondering if they let it rot (+ release CO2) or used it as some feed or fertilizer (keeping the carbon within the food chain).=== The thing about char, as a "way to sequester carbon" ...whether it comes from algae or not... ...Is that it's not just counting the carbon in the char that is buried, but should be counting the carbon in the biomass that grows within and around the char. I need a source, but it must be at least 4 times the weight of char, that biomass increases the initial weight by...(or words to that effect)....1 lb. char = 4 lb. sequestered CO2. ...roughly... once it's been fully colonized. Plus there is the enhancement of soil where more biomass is encouraged, again magnifying the sequestration effect....and there is the reduction in use of NPK pertro-fertilizers and other energy intensive practices to add into the net CO2 reduction equation. ...so it's not just the carbon of the char, but the reduced energy use & enhanced biomass too. ~:doh: Quote Link to comment Share on other sites More sharing options...
froggy Posted December 10, 2008 Report Share Posted December 10, 2008 Im not discounting char as a resource, Im discounting commercially grown algae as a feedstock. I think Terra Preta is a marvel. As to the benchtop, Im sorry but stupid lawyers proclude me from talking about certain things I work on or have signed on. Quote Link to comment Share on other sites More sharing options...
mervenvs Posted December 14, 2008 Author Report Share Posted December 14, 2008 I need a source, but it must be at least 4 times the weight of char, that biomass increases the initial weight by...(or words to that effect)....1 lb. char = 4 lb. sequestered CO2. ...roughly... once it's been fully colonized.Johannes Lehmann (Cornell Univ. I think) is one of the most visible researchers in the field, notably working in Brazil near historical terra preta sites. I'm not sure about the figures but he does claim that there is a positive humus gain (i.e. apart from the added charcoal, there is still a mass gain). I would be careful, because this observation is still controversial. Another group pointed out the fact that Lehmann's group only measures the top few cm of the soil (maybe 20 or 30, I don't remember). In their article, they observe that when you go deeper, there is an overall mass loss, due to enhanced microbacterial/fungal activity. So they cast doubt on the actual CO2 storage habilities of char. But as far as I remember this was done in Sweden (I think it's the same article I am thinking about), which obviously consists in very different conditions than the subtropical climate of historical TP sites. There have been a few discussions in Science or Nature recently between Lehmann and another guy.If you are interested, I can have a look at the names and links. I'll try to sum that up when I have a bit more time. Quote Link to comment Share on other sites More sharing options...
mervenvs Posted December 14, 2008 Author Report Share Posted December 14, 2008 Im not discounting char as a resource, Im discounting commercially grown algae as a feedstock. I think Terra Preta is a marvel.One of the main problems with commercially grown algae, one that is the most costly in term of technology and energy, is the difficulty to prevent "foreign" algae to compete with the desired species. But if you grow algae for char, you don't necessarily need a special species of algae. So you are less fussy about the temperature, etc... And might the best species win ! Probably, the local species. I think some projects invove algae as part of waste treatment. In this case, the mutiple interest of the stuff reduces the effective energy cost (since you should have to treat the water anyway, it might be overall more valuable to do such a process than to have another kind). In places like Australia, drying algae and charring it might be useful, especially in the view of gaining productive ground over the desert. Also, I am wondering if growing algae near the sea, partially with seawater, wouldn't be a way of harvesting nutrients in addition to carbon. To sum up, I am a bit doubtful about the possibility to grow algae for fuel (at least in the short term), but there could to be some specific were algae fulfills a combinations of requirments that will make it valuable enough to compete existing separate techniques. Quote Link to comment Share on other sites More sharing options...
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