Micro-discharge in porous ceramics for exhaust gas cleaning

摘要

In this study, a novel NO_x removal method using micro-discharge in porous ceramics for exhaust gas cleaning was examined. Micro-discharge consists of many discharges in narrow channels inside porous ceramics, and transition to flashover can be suppressed due to narrow channel. The micro-discharge was generated by 60Hz ac high voltage using 29 mm diameter ceramics plate with 10 W electrical input, and was applied for the cleaning of exhaust gas from diesel engine. Two kinds of ceramics with different pore size of 15 μm and 90 μm were used. Simulated gas consisted of NO, O_2, N_2 (0.01%, 10%, balance), and C_2H_4 (0%, 0.3% or 0.6%) was supplemented as additive at some conditions. NO oxidation experiments were carried out at 20°C and 150°C. As a result, oxidation ability without the C_2H_4 addition was higher than that with the additive at 20°C.