Simultaneous combined microbial removal of sulfur dioxide and nitric oxide from a gas stream.

A program is under way at the University of Tulsa to develop a viable process concept whereby a microbial process can impact on the problem of flue gas desulfurization and NOx removal. We have previously reported studies of SO2 reduction by Desulfovibrio desulfuricans and NOx reduction by Thiobacillus denitrificans. One potential process concept is the simultaneous combined removal of SO2 and NOx from cooled flue gas by contact with cultures of sulfate-reducing bacteria (SO2----H2S) and T. denitrificans (H2S----SO4(-2) as cultures-in-series or in coculture in a single contacting stage. Each of these contacting schemes has been investigated.