SBIR Phase I: Extraction of Lipids from Algal and Collection by Foam Fractionation

This Small Business Innovation Research Phase I project will develop a method for lysing algae and recovering the oil without pre-concentrating or dewatering. A promising feedstock for biofuels is photosynthetic algae, which can produce lipids in much higher yields per acre then can terrestrial crops. Currently, the harvesting and extracting of the oil consumes 40%-60% of the energy required to produce biodiesel from algae. If the lipids and other compounds can be collected directly from the growth media these expenses would be entirely avoided. Cavitation is a good candidate as it has been shown to rupture algal cell membranes and release cell contents. Feasibility of hydrodynamic jet cavitation as a practical and easily scalable method will be demonstrated. This process will be inline and will use shear flow and local accelerations to create high pressure fluctuations in the liquid causing bubbles to grow and collapse using a fraction of the energy required for ultrasonic cavitation. Hydrodynamic submerged jet cavitation also creates clouds of fine microbubbles that can attach to lipids and lift them to the surface. By controlling the creation and collection of foam, the lipids can be concentrated and recovered from the growth media with minimal energy input. The broader impact/commercial potential of this project is the development of new fuel resources that would benefit the nation by providing a stable energy source, reducing gas imports and dependence on foreign nations, and reducing greenhouse gas emissions. Commercialization of microalgae for biofuels and nutritional uses is expanding rapidly in the USA and the world. Eliminating the major energy requirements of harvesting and extraction will increase the profitability of biofuel production from algae. Providing a technology capable of achieving this will be very marketable. This technology could also be applied to other biotechnologies in which microorganisms are used to produce high value products, such as pharmaceuticals, nutraceuticals, or biorefining. This process could be used for more economical and more sustainable use of bioresources. In addition, greater understanding of the behavior of microorganisms in hydrodynamic flows would benefit the fields of biotechnology, health care, and water purification.