The effects of inner electrode shape on the performance of dielectric barrier discharge reactor for oxidative removal of NO and SO2

Abstract

Seagoing vessels are responsible for more than 90% of global freight traffic, but meanwhile, emission pollutants (NOx and SOx) of seagoing vessels also cause serious air pollution. Nonthermal plasma (NTP) combined with wet scrubbing technology is considered to be a promising technology. In order to improve the oxidation efficiency and energy efficiency of the NTP reactor, the screw and rod inner electrodes of dielectric barrier discharge (DBD) reactor were investigated. To analyze the mechanism, the optical emission spectra (OES) of NTP was measured and numerical calculation was applied. The experiment results show that the NO oxidation removal efficiency of screw electrode is lower than that of rod electrode. However, the SO2 removal efficiency of screw electrode is higher. According to the OES experiment and numerical calculation, the electric field intensity of the screw electrode surface is much higher than that of the rod electrode surface, and it is easier to generate N radicals to form NO. For the same energy density condition, the OH radical generation efficiency of the screw electrode reactor is similar to that of the rod electrode, but the gas temperature in the discharge gap is higher. Therefore, the SO2 oxidation efficiency of the thread electrode is higher. This study provides guidance for the optimization of oxidation efficiency and energy consumption of DBD reactor.