Diesel emission control system using combined process of nonthermal plasma and exhaust gas components' recirculation

A NOx aftertreatment system, using nonthermal plasma (NTP) reduction and exhaust gas components' recirculation, is investigated. A pilot-scale system is applied to a stationary diesel engine. In this system, NOx is first removed by adsorption, and subsequently, the adsorbent is regenerated by thermal desorption. NOx desorbed is reduced by using nitrogen NTP. Moreover, NOx, CO2, and water vapor recirculated into the engine intake reduce NOx. In this study, approximately 57% of the NOx of the exhaust (NOx: 240–325 ppm, flow rate = 300 NL/min) can be continuously treated for 58 h. A system energy efficiency of 120 g (NO2)/kWh is obtained.