多针-板脉冲放电处理模拟尾气中的NO_x

Treatment of NO_x in simulation exhaust by multi-needle to plate pulse discharge

机动车尾气中NO_x受到人们普遍关注。采用多针-板放电反应器,研究NO_x浓度变化随电气、气体等参数的变化规律,为脉冲放电去除NO_x提供一定理论支撑。结果表明:在一定条件下提高脉冲电压有利于NO转化;脉冲重复频率增大可提升NO_x去除率,脉冲重复频率达到一定值时NO_x去除率增幅不明显;流量增大利于NO转化,不利于NO_x去除;随氧浓度的升高NO转化率呈现先降低后升高,NO_x去除率逐渐降低。当氧浓度低于5%时,NO_x主要是通过NO还原成N_2;氧浓度高于5%时,NO主要通过氧化转化为NO_2。

NOx emission of motor vehicles has been widely concerned. In this paper, the relationship between the change of NOx concentration and electrical parameters, gas parameters was studied by using a multi needle plate discharge reactor, which provided some theoretical support for the NOx removal by pulsed discharge. The results show that the improvement of pulse voltage is beneficial to NO conversion under certain conditions;The removal rate of NOx can be increased by increasing pulse repetition frequency, while when the pulse repetition frequency reaches a certain value, the increase of NOx removal rate becomes less obvious;The increase of gas flow is beneficial to the conversion of NO, but go against the removal of NOx;with the increase of oxygen concentration, the conversion rate of NO decreased at first and then increased, and the NOx removal rate decreasedgradually. When the oxygen concentration is lower than 5%, NOx is mainly reduced to N2 by NO. When the oxygen concentration is higher than 5%, NO is mainly converted to NO2.