Modification and improvement of microalgae strains for strengthening CO2 fixation from coal-fired flue gas in power plants

Abstract Biological CO 2 capture using microalgae is a promising new method for reducing CO 2 emission of coal-fired flue gas. The strain of microalgae used in this process plays a vital role in determining the rate of CO 2 fixation and characteristics of biomass production. High requirements are put forward for algae strains due to high CO 2 concentration and diverse pollutants in flue gas. CO 2 can directly diffuse into the cytoplasm of cells by extra- and intracellular CO 2 osmotic pressure under high CO 2 concentrations. The flue gas pollutants, such as SO x , NO x and fly ashes, have negative effects on the growth of microalgae. This work reviewed the state-of-the-art advances on microalgae strains used for CO 2 fixation, focusing on the modification and improvement of strains that are used for coal-fired flue gas. Methods such as genetic engineering, random mutagenesis, and adaptive evolution have the potential to facilitate photosynthesis, improve growth rate and reduce CO 2 emission.