Removal of multi-pollutants in flue gas via a new approach based on dielectric barrier discharge coupling MnCu/Ti oxidation

Abstract

A dielectric barrier discharge (DBD) coupling MnCu/Ti oxidation and postpositioned wet electrostatic precipitator (WESP) system was built. The experimental results showed that WESP can significantly enhance the simultaneous conversion efficiency(ηC) of NO, SO2 and Hg0 by the DBD coupling MnCu/Ti reactor. The best simultaneous removal efficiency(ηR) of NO, SO2 and Hg0 reached 94.5%, 100% and 100%, respectively. The ratio of catalyst active component (Mn/Cu) and catalyst filling amount were optimized. The effects of catalyst active component ratio, filling amount, flue gas component and energy density (SED) on the ηC of NO, SO2 and Hg0 were determined. The effect of sodium humate (HA-Na) in the cleaning water on the ηR was also illustrated. Besides, we clarified the absorption mechanism and how WESP corona discharge oxidized NO, SO2 and Hg0, as well as the removal of NO2, SO2, and SO3 by HA-Na. Product analysis showed that NO2, SO2 and SO3 were converted into NO3- and SO42-, part of HgO was converted into Hg2+ in the cleaning water, and a small amount of Hg(NO3)2 and HgSO4 were converted into Hg2+, NO3- and SO42-.