Energy Efficiency Improvement of Nitric Oxide Treatment Using Nanosecond Pulsed Discharge

Pulsed streamer discharge plasmas, one type of nonthermal plasma, have been used to treat exhaust gases. Since a pulsewidth of applied voltage has a strong influence on the energy efficiency of the removal of pollutants, the development of a short-pulse generator is of paramount importance for practical applications. In this paper, a nanosecond (ns) pulse generator which has a 5-ns pulse duration in output pulsed voltage is developed, and NO-removal experiments using ns pulsed discharge were conducted. The experimental results of the NO removal showed 100% of NO-removal ratio at 7 pps of pulse repetition rate and the extremely high energy efficiency, which is 0.43 mol/kWh (12.9 g-NO/kWh) for NO removal (initial NO concentration = 200 ppm; gas flow = 2.0 l/min ). The result of deriving energy efficiency for NO removal indicated that the ns pulsed discharge has great advantage in energy efficiency for NO removal to the conventional discharge methods. By this research, the utility of the ns pulse plasma process was proven, and the influence of shorter pulse duration on NO-removal energy efficiency was confirmed.