抄録
Electrical discharge process using corona is effective in reducing particulate matter (PM), nitrogen oxides (NO_x) and total hydrocarbon (THC) contained in diesel engine exhaust. We experimentally evaluate the application of DC corona discharge reactor to reduce the PM and NO_x from diesel exhaust. Particulate trapping in a corona reactor can be accomplished by electrostatic precipitation. The accumulated PM on a nichrome electrode of reactor can be regenerated by the controlled burning process. In a corona reactor, the NO_x reacts with H_2O contained in exhaust at activated field. NO_x decreases as a result of HNO_3 formation in a reactor, and successively HNO_3 mist are adhered on the paper filter. A corona reactor consists of cylindrically-shaped outer electrode made of stainless steel and central electrode made of rolled nichrome wire. In this study, the effects of exhaust gas temperature and flow rate through a reactor on smoke degree reduction rate and NO_x removal rate are investigated by using a single reactor and multi-type discharge reactor. Also discussed is the particle size distribution of PM collected by a reactor.