Influence of NO Concentration on Removal Efficiency in Multipoint-to-Plane Electrode Dielectric Barrier Discharge Reactor

An influence of initial nitrogen monoxide (NO) concentration on removal efficiency with a multipoint-to-plane electrode dielectric barrier discharge (DBD) reactor was investigated experimentally. Several hundreds ppm NO was diluted with nitrogen and oxygen gas mixture (N2:O2=9:1) and was fed to the DBD reactor as a diesel exhaust simulated gas. The experimental results were evaluated using a simple model, which relates the change of NO concentration with input energy density (IED: J/L). About 50% of NO was removed with energy efficiency of 11 g/kWh at 200 ppm initial NO concentration. The energy efficiency at 100 ppm NO removal decreased from 11 to 6 g/kWh with increasing initial NO concentration from 200 to 500 ppm at sinusoidal applied voltage. The energy consumed in the reactor during one cycle of the applied voltage decreased from 8.5 to 2 mJ with increasing NO initial concentration from 50 to 300 ppm at 6.5 kVpp sinusoidal applied voltage. This energy decrease depended on the applied voltage waveform shape. The decrease of the consumed energy changed from 6.5 to 2 mJ by changing the applied voltage waveform shape from the sinusoidal to the pulse. The experimental results were also evaluated for the system performance of the reactor using the energy constant kE (L/J). The energy constant decreased exponentially with increasing of NO initial concentration.