Isolation and application of SOX and NOX resistant microalgae in biofixation of CO2 from thermoelectricity plants

Microalgae have been studied for their potential use in foodstuffs, agriculture, in the treatment of wastewater and, in particular, in the reduction of atmospheric carbon dioxide, the main cause of global warming. Thermoelectricity plants account for 22% of CO2 emitted into the atmosphere and native microalgae may be more tolerant to the gases emitted from burning fossil fuels. In the study presented here, microalgae were isolated from ponds next to a Thermoelectricity Plant, located in southern Brazil, and identified as Synechococcus nidulans and Chlorella vulgaris. The isolated microalgae were grown and compared with two different strains of microalgae, Spirulina sp. and Scenedesmus obliquus, for CO2 biofixation. The microalgae were exposed to 12% CO2, 60 ppm of SO2 and 100 ppm of NO, simulating a gas from coal combustion. The C. vulgaris had similar behavior to Spirulina sp., with 13.43% of maximum daily fixation. The microalgae with the greater fixing capacity were C. vulgaris and Spirulina sp. and these can be grown in electric power plants for CO2 biofixation of the coal combustion gas, which would help reduce global warming.

► Microalgae can help reduce global warming.
► Synechococcus nidulans and Chlorella vulgaris were isolated in a thermoelectric plant.
► Microalgae were compared with Spirulina and Scenedesmus obliquus for CO2 fixation.
► Microalgae were exposed to CO2, SO2 and NO, simulating a gas from coal combustion.
► C. vulgaris and Spirulina sp. showed 13.43% of maximum daily fixation.