Systematic Investigation of Biomass, Fatty Acid Productivity and CO2 Sequestration from Generator Gases by Fresh Water Microalgae in Photobioreactors for Biodiesel Application

The potential of microalgae as renewable energy feedstock for biofuel production is well recognized in developing countries and it is a large source of biomass for capturing CO2 on non-arable lands. In the current studies photobioreactor with 2 L capacity was used and operated with generator exhaust gases for algal CO2 sequestration. The reactor operated on generator exhaust gases with CO2 ranges from 500-8000 ppm. As CO2 concentration increased from 500 to 4000 ppm, there were steady increase in biomass 450 mg/l of dry weight till 2000 ppm, but above 2000 ppm there is decline in growth. The fatty acid profiles were more or less constant at all the CO2 concentrations and maximum lipid content was 48%. The maximum reduction in CO2 was 70% at 500 ppm whereas it was 52% at 4000 ppm. When CO2 concentration increased to 8000 ppm without air, algae could not sustain and showed decline in biomass content. CO2 fixation from generator gases not only reduces greenhouse gases but also help in getting fatty acid as biofuel.