Sustainable approach for simultaneously reducing CO2 and NO emissions from synthetic industrial flue gases using bacterial consortium and domestic wastewater in a suspended glass bioreactor

Abstract

The current study showed how a bacterial consortium (Bacillus tropicus SSLMC1 and Bacillus cereus SSLMC2) isolated from the harsh environment of Sambhar Salt Lake could simultaneously remove carbon dioxide (CO2) and nitric oxide (NO) while using domestic wastewater (DWW) as nutrients and an energy source. A 3-L suspended glass bioreactor was used for the lab tests to see how well the bacterial consortium would be able to fix CO2 and NO from three different gaseous mixtures (only CO2, only NO and a mixture of CO2 and NO). The simultaneous removal of CO2 and NO was shown to have the highest values of biokinetic parameters such as biomass productivity, specific growth rate, fixation efficiency, fixation rate, utilization efficiency and nutrient utilization efficiency. The starting and final amounts of nutrients and pollutants present in DWW were examined for checking the simultaneous removal of CO2 and NO. The presence of fatty acids, fatty alcohols and long-chain hydrocarbons found in cell lysate and cell-free supernatant was analysed using Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectroscopy (GC–MS). The potential mechanism for the bio fixation of CO2 and NO was presented based on the findings of the experimental work and the product analysis. The resulting biokinetic characteristics were compared to those from earlier studies and showed that using DWW as a nutrient and energy source would allow bacterial consortia to simultaneously biofix CO2 and NO.