703 非平衡プラズマを用いたディーゼルエンジン排ガス中のNOxの除去(OS-6 ディーゼル燃焼・排ガス浄化)

Abstract

Two-stage plasma and chemical reactors was investigated for the control of NOx in an exhaust gas of diesel engine. Previous results was shown that nonthermal plasma was able to oxidize NO to NO_2 with low power consumption but cannot convert NO_2 to N_2 effectively. Rather, part of the NO_2 is converted to form N_2O,NO_3 and HNO_3 despite of any additives or catalysts. As an alternative technology, the two-stage plasma and chemical reactors were developed : the plasma reactor to convert NO to NO_2, and the chemical reduction process to convert NO_2 to Na_2SO_4 using Na_2SO_3 as reducing chemical resulting in minimum reaction byproducts (NO, CO, N_2O). The plasma reactor without chemical reactor oxidized nearly 100% of 325ppm NO with minimum byproducts.