FACTORY FARMED BIOFUEL
Biofuel From Algae
by Ramesh Suri, October 16, 2006
Algae are microscopic, single-celled plants, growing in an aqueous environment.
For growth algae make use of sunlight as energy source and simple inorganic nutrients, predominantly CO2, soluble nitrogen components and phosphates. For many years, there has been a theory that noxious flue gases produced by industries could be substantially reduced by using algae. The algal biomass produced can then be used for generating high-energy biofuel. In the case of the cement industry, the biofuel produced can be directly fired in captive power plants and kilns.
Characteristics of algae cultivation are:
- The productivity per area is 2 to 5 fold higher as compared with traditional agricultural crops and fast growing ‘energy crops.’
- Lower quality water can be used for growing algae, e.g. the effluent of biological waste water treatment facilities.
- Algal systems can remove CO2 (and NOx) from flue gases.-
Many algal species produce valuable products, such as colorants, polyunsaturated fatty acids and bioactive compounds. These ‘fine chemicals’ are applicable as a natural ingredient in food products, pharmaceuticals, food supplements and personal care products.
- After extraction of these valuable compounds the remaining biomass (approx. 80%) can be used for production of ‘green’ electricity and heat. Alternatively, microalgae can be used for the production of methylesterfuel (bio-diesel).
Finding renewable energy sources has been a top concern for many scientists around the world and algae based biofuel has emerged as a viable resource. At present there are two common methods for algae based biofuel production: open ponds and bioreactors. The major technical challenges of these systems are how to: sustain highest photosynthesis and biomass productivity, reduce cell damage by hydrodynamic stress, reduce costs in fabrication, installation, and maintenance, and increase the capability of the system to expand to an industrial scale.
From 1978 to 1996, the U.S. Department of Energy’s Office of Fuels Development funded a program to develop renewable transportation fuels from algae. The main focus of the program, know as Aquatic Species Program (or ASP), was the production of biodiesel from high lipid-content algae grown in ponds utilizing waste CO2 from coal fired power plants. The study demonstrated that more than 300 species of algae were well suited to the task. Gaseous emission was pumped through the base of a pond and algae grown on the surface. The project was eventually abandoned because of the difficulty in harvesting algae and high cost of energy required to agitate the pond to ensure sufficient algal exposure to sunlight. As photosynthesis efficiency is driven by complex cellular mechanisms that depend on having just the right exposure to light, past algal systems grew to be complex and ultimately too expensive for most industries to contemplate. They took the form of huge, shallow ponds with extensive pumping and distribution mechanisms.
GreenFuel Technologies Corp., a Massachusetts based research company, working in collaboration with theMassachusetts Institute of Technology (MIT), using the air-lift bioreactors for algal growth on flue gas, has succeeded in reducing the capital investment by streamlining the harvesting of algae, limiting the energy required to operate the system, automating many of the necessary controls (e.g., flow controllers and gas uptake), and minimizing the physical space required.
SCHEMATIC OF AN AIR LIFT BIOREACTOR
Solid arrows indicate the direction of the gas flow;
open arrows indicate the direction of the liquid flow.
GreenFuel uses an implementation of an air-lift reactor (ALR), which is a type of pneumatic contacting device in which fluid circulation takes place in a defined cyclic pattern through channels built specifically for this purpose. The process, called photomodulation, rotates the algae in and out of the sunlight. On the basis of the ALR principles and the specific requirements of photosynthetic processes, a “triangular” ALR configuration was developed that is particularly suitable for algal growth. The GreenFuel bioreactor consists of a riser tube or channel, a gas separator, and a down comer tube or channel. The difference in the apparent fluid densities between the riser and down comer provides the driving force for liquid circulation. Air-lift reactors (ALRs) have great potential for industrial bioprocesses, because of the low level and homogeneous distribution of hydrodynamic shear.
In the GreenFuel Technologies beta system at MIT, a slipstream from the MIT Cogeneration Plant is passed directly from a sampling port on the stack into a bank of triangle-shaped bioreactors containing algae in a salt water growth medium. Each bioreactor is self-contained; the gas enters at the bottom two vertices, and makes a single pass though the tubular bioreactor before exiting at the top vertex. The bioreactor dimensions-approximately 8 feet tall by 6 feet long by several inches wide-are determined by the amount of time required for the gas to dissolve in the growth medium as it rises through the vertical and hypotenuse legs (The triangle design is patented by GreenFuel).
Greenfuel Technologies)
The GreenFuel team has been growing algae on the Cogen gases, and harvesting algae ‘crops’ daily. Algae reduced NOx day and night, regardless of temporal and weather conditions. The process is essentially an effect of the surface configuration of the algae cell walls. Even dead algae can reduce NOx up to 70 percent. The harvested algae can be used to generate biofuel products. A week-long evaluation by a third party called CK Environmental Inc. certified that over the seven-day test period, the GreenFuel beta system simultaneously removed 85.9 percent NOx (2.1 percent, regardless of weather conditions), and 82.3 percent CO2 (12.5 percent) on sunny days, or 50.1 percent CO2 (6.5 percent) on cloudy or rainy days. The testing methods conformed to EPA standards for measuring NOx and CO2 emissions.
The Academic and University Centre in Nove Hrady, Czech Republic developed a closed tubular photobioreactor. This “penthouse-roof” photobioreactor was based on solar concentrators (linear Fresnel lenses) mounted in a climate-controlled greenhouse on top of the laboratory complex combining features of indoor and outdoor cultivation units. The dual-purpose system was designed for algal biomass production in temperate climate zones under well-controlled cultivation conditions and for heating service water with surplus solar energy.
Greenshift Corporation
GreenShift Corporation has acquired rights to Ohio University’s patented cynaobacteria based bioreactor process for reducing greenhouse gases emissions from fossil-fuel combustion processes. Dr. David Bayless at OU designed a bioreactor based on a newly discovered iron-loving cyanobacterium (blue-green algae). In concept, this is very similar to GreenFuel Technology’s reactor. The algae grown in the bioreactor on 60 by 120-centimeter membranes of woven fibers resembling window screens interspersed between the Oak Ridge glow plates. Capillary action wicks water to the algae, fiber optic cables channel sunlight into the glow plates, and ducts bring in the hot flue gas. Spreading the cyanobacteria on membranes maximizes surface area for growth, minimizes water and optimizes the use of sunlight. The algae use the available carbon dioxide and water, giving off pure oxygen and water vapor in the process. The organisms also absorb nitrogen oxide and sulfur dioxide. A prototype is capable of handling 140 cubic meters of flue gas per minute, an amount equal to the exhaust from 50 cars or a 3 megawatt power plant. Once the algae grow to maturity, they fall to the bottom of the bioreactor and are used as feedstock and fertilizers. The biomass can also be utilized for producing biodiesel.
Future research in this area would involve determination of the operational and economic feasibility of such systems for organic biomass production from the viewpoint of cement industry. This would lead to sequestration of CO2 produced from cement manufacturing and production of biofuel as an alternate fuel.
References:
Novakovic, G.V., Kim, Y., Wu, X., Berzin, I., and Merchuk, J.C., 2005. Air-Lift Bioreactors for Algal Growth on Flue Gas: Mathematical Modeling and Pilot-Plant Studies. Ind. Eng. Chem. Res. Vol. 44, pp. 6154-6163.
Sheehan, J., Dunahay, T., Beneman, J. and Roessler,P., 1998. A Look Back at the U.S. Department of Energy’s Aquatic Species Program Biodiesel from Algae. U.S. Department of Energy, Office of Fuels Development.
De Boer, A.J., and van Doorn, J., 1998. Combined production of chemicals and biomass with microalgae in a closed photobioreactor. ECN Contribution to the 10th European Conference: ‘Biomass for energy and industry’. ECN RX-98-003, pp. 27-29.
Reith, J.H., van Doorn, J., Mur, L.R., Kalwij, R., Bakema,G. and van der Lee, G., 2000. Sustainable co-production of natural fine chemicals and biofuels from microalgae. Conference Biomass for Energy and Industry, Sevilla, June 2000.
Bayless, D.J., et al., 2002. Enhanced Practical Photosynthetic CO2 Mitigation (http://www.netl.doe.gov/publications/proceedings/01/carbon_seq/5a4.pdf)
Masojídek, J., Papácek, S., Sergejevová, M., Jirka, V., Cervený, J., Kunc, J., Korecko, J., Verbovikova, O., Kopecký, J., `tys, D. and Torzillo, G., 2003. A closed solar photobioreactor for cultivation of microalgae under supra-high irradiance: basic design and performance. Journal of Applied Phycology, Vol. 15, pp. 239-248.
Website References:
GreenFuel: Using Algae to Capture Emissions
Vision: The World Student Community for Sustainable Development, April 22, 2005
Greenshift Licenses Bioreactor Technology
Green Car Congress, December 12, 2005
Beta Test Set for Emission-Fighting Algae Bioreactor
Power Engineering International, November 2004
Blue Green Acres
Scientific American, August 29, 2005
Algae Emissions Reduction Concept Shows New
Editor’s Note: With every new technology there is a lot of hype, especially when it is green technology. Biofuel is no exception. In the realm of new green energy technologies not only is the holy grail of abundant energy held forth by entrepreneurs to investors as an irresistable temptation, there is also the claim that we will save the planet. Heady stuff.
We’ve been aggressively covering developments in biofuel for quite some time now, and we’ve learned a few things. First of all, using the best crops out there, such as palm oil for biodiesel and sugar cane for bioethanol, you will get an economically viable crop. But at 6,000 barrels of fuel per square mile per year, you will not get a substitute for petroleum. In fact, to replace worldwide petroleum use with biofuel you would have to consume 10.8 million square miles of farmland with the highest yielding biofuel crops, and there are only 5.8 million square miles of farmland on earth.
We’ve also learned that the biofuel boom is already having unintended negative consequences. It’s crowding out food production and driving up food prices in nations where many of the poorer citizens already can’t afford to buy enough food. It is also encouraging new rounds of deforestation in regions where deforestation for rangeland, farms and timber harvesting are still out of control. Clearly, biofuel is a new technology with potential, but it is also problematic. A conscientious environmentalist will undoubtedly make a nuanced appraisal of biofuel, not a total endorsement.
Now we have a new concept - factory produced biofuel. In the following assessment of biofuel produced in a “bioreactor” from algae, the pitfalls of producing biofuel from algae ponds is recognized, and then the author explains the potential to produce biofuel within illuminated, enclosed containers, infused with carbon dioxide. While much more needs to be learned, it is certainly possible this process could become economically viable, and could result in a far higher contribution from biofuel to the ever increasing fuel requirements of civilization. - Ed Ring
http://ecoworld.com/features/2006/10/15/factory-farmed-biofuel/
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DOE Doles Out Bucks for Biofuel Producers
Greentech Media
10/10/08 - 04:08 PM EDT
Written by Rachel Barron
Novozymes said Wednesday it scored $12.3 million from the U.S. Department of Energy to develop enzymes that would help cut the cost of producing cellulosic ethanol.
Enzymes are used to help break down the starch of cellulose feedstocks, such as switchgrass, corncobs and woodchips, and turn them into sugars. The sugars are then fermented and distilled to become ethanol. The government expects something in return for its investment. The deal calls for the Danish company to increase the efficiency of the enzymes by two folds.
To accomplish this goal, Novozymes will match the DOE's funding, bringing the total amount invested into the project to $25 million. The company said it will have the cost-cutting enzymes ready for the commercial market by 2012.
This is the second time the company has received funding from the DOE. In 2001, Novozymes bagged $18 million from the federal government, again to improve enzymes used in producing biofuels.
The company has received government support at a time when private industry investments are harder to come by. Doing research and building biofuel refineries are multimillion-dollar undertakings, but raising money will be difficult while the financial market continues to take its lumps. Commercializing biofuel technologies could take longer as a result, Arnold Klann, CEO of waste-to-ethanol company BlueFire Ethanol, told Reuters last week.
Still, the biofuel industry keeps moving forward. Here's a breakdown:
Mascoma Corp. said Tuesday it grabbed $26 million from the DOE and $23.5 million from the State of Michigan to build a cellulosic ethanol plant. The plant, which will be located in Michigan's Chippewa County, will produce 40 million gallons of ethanol per year from woodchips. Mascoma and JM Longyear, a timber and mining company, plan to form Frontier Renewable Resources to own and operate the new plant.
The food vs. fuel debate continued to brown biofuels' green image Tuesday when the United Nations Food and Agriculture Organization released a report that found that biofuel subsidies and policies contributed to rising food prices. The U.N. agency called for biofuel policies and subsidies to be reviewed right away in an effort to preserve the world's food security. The report did have some positive things to say about next-generation biofuels such as cellulosic ethanol, which it said could reduce the fossil energy used and greenhouse gasses produced during biofuel production.
We all need a plan to accomplish a goal. And some of us need a plan to create a plan. And that's basically what U.S. Departments of Agriculture and the DOE said Tuesday when the agencies outlined the steps needed to accomplish the country's goal of cutting U.S. gasoline consumption by 20 percent over the next 10 years. Titled the National Biofuels Action Plan, the plan calls for interagency efforts to help drive the development of a sustainable biofuel production. For example, a group led by the USDA, DOE and the Environmental Protection Agency is defining the criteria to be used when assessing the sustainability of biofuel production. And another interagency group is creating a 10-year technology research plan for developing cost-effective ways for producing cellulosic ethanol.
In April, the United Kingdom required those supplying more than 450,000 liters (118,890 gallons) of fossil fuel-based transportation to make sure up 2.5 percent of their fuels sold are coming from biofuels over the next year. But that wasn't all. The biofuels will also have to meet the U.K. government's environmental standards. According to an interim quarterly report published Tuesday by the U.K.'s Renewable Fuels Agency, biofuels supplied by several companies, including BP (BP Quote - Cramer on BP - Stock Picks) and Exxon Mobil (XOM Quote - Cramer on XOM - Stock Picks) subsidiary Esso, have so far failed to meet the country's green standards.
Ethanol producer Poet said Tuesday it is getting the total funding the DOE promised last year. In February 2007, the DOE said it would give Poet up to $80 million to build a commercial ethanol plant that makes fuel from corn as well as corn fiber and cobs. The first part of the deal with the government gave the Sioux Falls, S.D.-based company $3.7 million to help with the preliminary design of the plant and feedstock collection. Now, the company is getting the remaining $76.3 million for construction and plant operation. Upon completion, the plant will make 125 million gallons ethanol per year, 25 million of which will be from corn fiber and cobs. Construction on the plant will begin in 2009, and cellulosic fuel production could come as early as 2011, the company said.
http://www.thestreet.com/print/story/10441893.html
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