Experimental study on the influence of H ₂ O vapor and O ₂ for desulfurization and denitrification of the diesel exhaust in marine application by non‐thermal plasma

Abstract

Abstract To improve the pollutant removal efficiency by non‐thermal plasma (NTP), the effect of H 2 O vapor and O 2 on removal efficiency of NO and SO 2 as well as the reduction of CO was investigated in H 2 O/O 2 /SO 2 /NO/C 3 H 6 /CO 2 /N 2 system. To analyse the reaction mechanism, the effects of H 2 O vapor and O 2 on the emission intensity of and were investigated. The experimental results show that the increase of H 2 O vapour (0%–9.8%) promotes the generation of OH radicals, increases the removal efficiency of NO from 18.9% to 57.3%, decreases the energy per NO removed from 449.0 to 148.1 eV/NO, increases SO 2 removal efficiency from 4.8% to 35.3%, decreases the energy per SO 2 removed decreases from 2784.0 to 582.9 eV/SO 2 , and reduces the generation of CO from 460 to 229 ppm. In the range of 0%–15%, the increase of O 2 content promotes the formation of O radicals, increases the removal efficiency of NO from 8.5% to 54.2%, and decreases the energy per NO removed from 994.3 to 156.4 eV/NO. In the range of 0%–5%, increasing O 2 content promotes SO 2 removal efficiency from 8.7% to 24.8%, and decreases the energy per SO 2 removed from 2485.7 to 876.6 eV/SO 2 . However, CO generation increases from 200 to 350 ppm with the increase of O 2 in 0%–5% due to the incomplete oxidation of C 3 H 6 . In the range of 5%–15%, the increase of O 2 produces more O radicals, decreases the removal efficiency of SO 2 from 24.8% to 23.5% and the generates of CO from 350 to 311 ppm. This study is helpful for improving the efficiency of NTP for desulfurization and denitrification, while reducing the by‐product CO.