Oxidation characteristics of mixed NO and Hg0 in coal-fired flue gas using active species injection generated by surface discharge plasma

The oxidation characteristics of mixed NO and Hg0 were investigated using active species injection under oxygen atmosphere, namely, a surface dielectric barrier discharge plasma (SDBD) reactor inserted in simulated flue duct was used to generate and inject the oxygen-based active species into the flue gas to simultaneously oxidize NO and Hg0 at 110 °C. Approximately 92.5% and 99.1% of NO and Hg0 were oxidized at 301.8 J L−1, respectively, a reaction competition between NO and Hg0 with active species existed, and the NO oxidation was faster. The effects of important flue gas components on NO and Hg0 oxidation were investigated. H2O enhanced the NO oxidation, but inhibited the Hg0 oxidation. HCl exhibited a promotional effect on the Hg0 oxidation, but displayed no effect on the NO oxidation. SO2 and H2O showed obviously inhibitory effect on the NO and Hg0 oxidation. Ozone and O2 metastable states contributed to the NO and Hg0 oxidation. NO2, HNO3 and N2O5 were observed by Fourier transform infrared spectroscopy (FTIR).