Large-Scale Microalgae Cultivation in Agricultural Wastewaters for Biofixation of CO2 and Greenhouse Gas Abatement

76092-Novel, cost-effective technologies are needed to stabilize and reduce greenhouse gas emissions. Microalgae have been shown to be able to fix carbon dioxide (CO2) at high rates, producing a biomass that can be converted to fuels and chemicals to replace fossil fuels. However, additional research is needed to increase the efficiency of CO2 fixation and develop techniques for managing algal cultures in large-scale applications. This project will develop large-scale microalgae-based carbon sequestration technologies using power plant flue gases for CO2 and agricultural wastewaters as nutrient sources. The algal biomass harvested from the mass culture ponds will be converted to methane fuel, a substitute for fossil fuels, with the residues used as fertilizers. In Phase I, novel strains of microalgae with high capacity for CO2 fixation will be isolated and cultured on nutrient-rich agricultural wastewaters, to demonstrate the potential of the technology. Also, an innovative means for harvesting the algal biomass and converting it to biofuels (methane gas) will be investigated. Commercial Applications and Other Benefits as described by the awardee: In addition to the capture and recycling of power plant flue gas CO2, the new process should result in the production of biofuels and fertilizers. Because these products will provide sufficient revenue, the abatement of greenhouse gas emissions can be accomplished, even without a commercial return from this beneficial function.