低温等离子体处理柴油机NO_x和PM试验研究

Investigation on treating NO_x and PM in diesel engine exhaust by non-thermal plasma

建立了一种具有较强实用性的介质阻挡放电等离子体反应器试验装置。借助静态试验研究其放电特性,通过发动机台架试验探讨了利用低温等离子体处理柴油机2种主要有害排放物NOx和PM的效果和化学反应机理,并通过模拟试验作了处理PM的进一步验证。试验结果表明,放电功率对于低温等离子体活性成分的产生有重要影响,应当优选放电参数以获得高的放电功率从而达到更好的处理效果;采用低温等离子体处理柴油机排气,NOx总量变化不大,主要将NO转化成NO2;低温等离子体可以有效去除柴油机排气中的PM,去除率随能量密度的增大而提高。

A practical non-thermal plasma generator was designed and its discharge characteristic was researched through static experiment,then experiment was done to research the effect of treating NOx and PM in diesel exhaust by non-thermal plasma and the chemical mechanism was discussed. The process of treating PM by non-thermal plasma was verified through simulation experiment.The results show that discharge power is very important of producing active components for chemical reaction.When selecting proper discharge parameter,high discharge power can be obtained,thus removal efficiency may be improved.When treating NOx in diesel exhaust by non-thermal plasma,most NO is oxidized to NO2,but total amount of NOx has no obvious change.PM in diesel exhaust can be decomposed efficiently when treated by non-thermal plasma, and the removal efficiency can be improved when energy density is improved.