不同进气方式对热等离子体应用于CH4-CO2重整的影响

采用大功率双阳极热等离子体装置, 对CH4-CO2重整制合成气进行实验研究. 实验采用两种不同的原料气输入方式: 一种是使原料气(CH4和CO2的混合气体)作为等离子体放电气体全部通入第1阳极与第2阳极间的放电区, 直接参与放电; 另一种是保持前述状态, 再附加另一部分原料气通入从等离子体发生器喷出的等离子体射流区. 实验表明: 第1种方式下, CH4和CO2同时具有很高的单程转化率和反应选择性, 但能量转化效率较低; 第2种方式下, 尽管CH4和CO2单程转化率和选择性有所降低, 但由于进料量增加, 所得合成气摩尔量较大, 因此能量转化效率高于第1种进气方式所得结果. 实验还发现, 保持放电电流恒定的情况下, 等离子体放电电压随通入第1阳极与第2阳极间放电区的原料气流量增加而增加, 与通入等离子体射流区的流量无关, 同时实验未发现等离子体发生器阴极和阳极被氧化或出现碳沉积现象.

Effect of Different Feeding Modes on CO_2 Reforming of CH_4 by Thermal Plasma

CO_2 reforming of CH_4 was investigated using binode thermal plasma at atmospheric pressure. The experiment was conducted in two modes. One was to introduce the feed gases (CH_4 and CO_2) into the discharge region between the first anode and the second anode of the plasma generator as plasma forming gas; the other was to introduce the feed gases into the discharge region and also into the plasma jet from the exit of the plasma generator. Experimental results show that the conversion of feed gases and the selectivity of products by the former mode are higher than that by the latter. However, the energy conversion efficiency was less because of the larger feed flux and the higher amount of synthesis gas produced in the latter mode. Furthermore, during discharge in both modes, the discharge power was affected only by the feed flux into the plasma generator but the feed flux into the plasma jet, and oxidation on the cathode and anode or carbon deposition in the plasma generator was not observed in any experiments.