The increased usage of fossil fuels has led to increase in the concentration of CO2, which is a greenhouse gas responsible for global warming. Algae-based CO2 conversion is a cost-effective option for reducing carbon footprint. In addition, algae-based CO2 mitigation strategy has the potential to obtain valuable products at the end of the process. In the present study, freshwater algal species were isolated and identified for CO2 capture, such as Hydrodictyon, Spirogyra, Oscillatoria, Oedogonium, and Chlorella. The algal strains were screened based on different parameters like fast growth rate, high rate of photosynthesis, strong tolerance to the trace constituents of other gases (gaseous hydrocarbons, NOx, SOx, etc.), high temperature tolerance, and possibility to produce high value products, etc. The study involves integrated methods for utilizing 90–99% CO2 from a natural gas processing industry (GAIL India, Ltd.) as well as 13–15% of CO2 from flue gas of thermal power plants (Chandrapura and Santaldih Thermal Power Station) as carbon nutrient source along with the additional nutritional supplements. A 400-ml and 25-l flat panel photo-bioreactor (PSI Photo-bioreactors) was used for CO2 capture. After CO2 capture, the algal biomass was used to extract value-added products such as amino acid rich feed, algal oil, algal pellets, etc.
Part of the book: Algae