Utilization of simulated flue gas containing CO2, SO2, NO and ash for Chlorella fusca cultivation

• Chlorella fusca LEB 111 tolerated up to 400 ppm SO2 and NO.
• 40 ppm thermal coal ash did not affect cell growth.
• Industrial wastes added to cultures did not affect the biomass composition.

Microalgae can use the CO2 from coal power plants in their metabolic pathways. However, these microorganisms must be able to tolerate other residues produced from burning coal. This study evaluated the wastes addition (CO2, SO2, NO and ash) present in the flue gas from a coal power plant on the growth parameters during culture, CO2 biofixation and on the biomass characterization of Chlorella fusca LEB 111. The SO2 and NO injection (until 400 ppm) in cultivations did not markedly affect CO2 biofixation by microalga. The best CO2 biofixation efficiency was obtained with 10% CO2, 200 ppm SO2 and NO and 40 ppm ash (50.0 ± 0.8%, w w−1), showing a specific growth rate of 0.18 ± 0.01 d−1. The C. fusca LEB 111 biomass composition was similar in all experiments with around 19.7% (w w−1) carbohydrates, 15.5% (w w−1) lipids and 50.2% (w w−1) proteins.