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

Abstract

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.

Characteristics and Activities of Sulfate-Reducing Bacteria

“…The utilization of S02 from flue gas desulfurization process by D. desulfuricans appears feasible (Lee and Sublette, 1991) and has economic potential (Sublette and Gwozdz, 1991). Desulfotomaculum orientis can be grown on H 2 • CO 2 , and S02 with the production of H 2 S, while D. desulfuricans transforms S02 to H 2 S, using minerals and pretreated sewage sludge (Deshmane et al, 1993).…”

Denitrification and nitric oxide reduction in an aerobic toluene-treating biofilter

“…This was done because the presence of high nitrate concentrations could inhibit the reduction of NO or nitrogen dioxide (NO 2 ) as nitrate is a more favorable electron acceptor than either of these compounds (Fig. 1) (Lee and Sublette, 1991).…”

High-efficiency removal of NO x by a novel integrated chemical absorption and two-stage bioreduction process using magnetically stabilized fluidized bed reactors

“…Figure 6 also indicates that Fe(II)EDTA-NO concentrations increased with increasing SO 2 concentrations. Lee and Sublette [36] noted that SO 3 2 had an inhibition effect on denitrifying bacteria. Furthermore, SO 3 2 and SO 4 2 would be reduced to S 2 in the bioreactor, which inhibited Fe(II)EDTA-NO reduction [37].…”