Development of suitable photobioreactors for CO2 sequestration addressing global warming using green algae and cyanobacteria

CO₂ sequestration by cyanobacteria and green algae are receiving increased attention in alleviating the impact of increasing CO₂ in the atmosphere. They, in addition to CO₂ capture, can produce renewable energy carriers such as carbon free energy hydrogen, bioethanol, biodiesel and other valuable biomolecules. Biological fixation of CO₂ are greatly affected by the characteristics of the microbial strains, their tolerance to temperature and the CO₂ present in the flue gas including SO_X, NO_X. However, there are additional factors like the availability of light, pH, O₂ removal, suitable design of the photobioreactor, culture density and the proper agitation of the reactor that will affect significantly the CO₂ sequestration process. Present paper deals with the photobioreactors of different geometry available for biomass production. It also focuses on the hybrid types of reactors (integrating two reactors) which can be used for overcoming the bottlenecks of a single photobioreactor.