Evaluation Of A New Approach For Nox Removal From The Flue Gas In Lab-Scale

A chemical absorption-biological reduction integrated approach is developed to achieve the NOx removal from the flue gas. In this integrated process, NO (the primary component of NOx) is chelated by Fe(II)EDTA and subsequently reduced to N2 by microorganism. Fe(III)EDTA formed via oxidation of Fe(II)EDTA by oxygen in the flue gas is simultaneously and biologically reduced back to Fe(II)EDTA. During the steady state operation, the integrated approach for the NO removal can be achieved to 90%, in comparison with 29% by the water-based biofilter. Moreover, full breakthrough of NO was observed in the scrubbing process after 5 h of operation at the same condition. Two dedicated bacterial strains (a Fe(II)EDTA-NO reducing bacterium and Fe(III)EDTA reducing one) were isolated and characterized. The competition between Fe(III)EDTA and Fe(II)EDTA-NO reduction was also investigated with the mixed cultures.