Efficient processing of algal bio-oils for biodiesel production

Biodiesel is a clean-burning, renewable fuel produced from domestic agricultural sources (such as vegetable oils and animal fats) that can be blended with petroleum diesel and used by most compression-ignition (diesel) engines with few or no modifications. However, the availability of suitable agricultural fats and oils for biodiesel feedstock is limited, and is not expected to increase apace with increased demand from biodiesel producers. Microalgae (microscopic photosynthetic organisms) have been considered as a potential source of bio-oils suitable for biodiesel feedstock, due to their rapid growth rates relative to terrestrial plants and lack of direct competition for agricultural land with food crops or dedicated energy crops (e.g., corn for ethanol). This project will address the two most significant obstacles to the commercial production of bio-oils from photosynthetic microalgae: (1) the low densities of cultures associated with photosynthetic cultivation, leading to high land footprints and downstream processing costs; and (2) the general difficulty of extracting and purifying the bio-oils using techniques that consume minimal amounts of energy. Phase I will evaluate the quality of the biodiesel produced from microalgal bio-oils by two candidate processes, assess their total energy costs, and identify the process with the greatest potential for commercialization. Phase II will optimize the selected process, conduct a full cost and energy analysis, and determine the best path for scaling up to commercial production. Commercial Applications and other Benefits as described by the awardee: The technology should result in a commercially viable process for producing biodiesel from algal bio-oils. Specific beneficiaries in the commercial sector include the commercial trucking, construction, and agriculture industries; railroads, shipping, and maritime industries; and manufacturing industries ¿ all of which have significant transportation and energy costs tied to petroleum diesel prices. Federal sector beneficiaries include the military (currently, the largest user of biodiesel in the U.S.), agencies with large diesel-powered truck fleets (e.g., the U.S. Postal Service), and agencies operating on-road and off-road diesel vehicles in sensitive environments (e.g., National Park Service, Fish and Wildlife Service).