Dual-course dielectric barrier discharge with a novel hollow micro-holes electrode to efficiently mitigate NO_x

The effect of a novel hollow annular micro-hole electrode on the DBD de-NO_x performance was investigated. The experimental results show that the hollow electrode allows the feed gas to take full advantage of the redundant heat of the electrode, thus reducing the energy consumption of the system. Subsequently, the micro-hole structure can improve the uniformity of feed gas in the plasma channel and prolong the residence time of the feed gas in the plasma channel. The reactor can also raise the temperature of the feed gas and enhance the plasma electric field. The optimum NO_x removal efficiency of about 82.6% is achieved at 16 annular micro-holes. Compared to the rod electrode reactor, the novel electrode reactor shows 19.7% reduction in energy consumption and 13.2% enhancement in de-NO_x efficiency. The calculations of de-NO_x mechanism show that the NO₂ concentration decays significantly as the feed gas residence time increases, accompanied by a slight increase in N₂O concentration. The NO₂ concentration marginally increases while N₂O concentration slightly decreases as the increase of feed gas temperature. DBD de-NO_x presents the mode of accelerated reduction of NO, essential removal of NO₂, and gradual consumption of N₂O with the reduced electric field increases.