烟气条件对直流电晕自由基簇射NO氧化过程的影响

Effect of Flue Gas Conditions on NO Oxidation Process by DC Corona Radical Shower

运用以湿空气为自由基源物质的直流电晕自由基簇射系统,研究了烟气在反应器内的滞留时间、烟气流速和NO浓度对NO氧化过程的影响.结果表明:烟气流速的增加会抑制电晕放电的发展,而烟气中NO浓度的增加则使放电变得更加容易.NO的氧化受烟气在反应器内滞留时间的影响较小,而它受烟气流速的影响较大.在2W的输入功率下,当烟气在反应器内的滞留时间从8 5s增加到34 .2s时,NO的氧化率只从5 4 . 5 %提高到5 7 .6 %.而在1 7W·h/m3 的能量密度下,当烟气流速从1 . 4cm/s增加到6 .3cm/s时,NO的氧化率从6 0 0 %减少到38 .6 %,能量利用率也从2 0 . 8g/ (kW·h)下降到了1 3 .3g/ (kW·h) .在湿空气流量一定的情况下,NO初始浓度存在一个最佳值,本实验中最佳的NO浓度为1 0 0×1 0 -6左右.

Using an air-H_2O DC corona radical shower system, the influences of reside time of flue gas in the reactor, velocity of flue gas and NO concentration on NO oxidation process were studied. The results show that the increasing velocity of flue gas can restrain corona development and the increasing NO concentration can make discharge more easy. The reside time of flue gas in the reactor has less effect on the NO oxidation. The NO oxidation rate increased only from 54.5% to 57.6% at 2W input power when the reside time of flue gas in the reactor increased from 8.5s to 34.2s. However, the velocity of flue gas has important effect on the NO oxidation. At 1.7W·h/m3 energy density, when the velocity of flue gas increased from 1.4cm/s to 6.3cm/s, the NO oxidation rate droped from 60.0% to 38.6% and the energy yield also falled from 20.8g/(kW·h) to 13.3g/(kW·h). Under the certain flux of humid air, NO initial concentration has a best value, which was about 100×10 -6 in this experiment.