Abstract
The NO_x aftertreatment system, using nonthermal plasma (NTP) reduction and NO_x recirculation, is investigated. A pilot-scale system is applied to a stationary diesel engine generator. In this system, NO_x is first removed by adsorption, and subsequently, the adsorbent is regenerated by thermal desorption using the waste heat of the exhaust gas. The desorbed NO_x is reduced by nitrogen NTP. Moreover, ambient air is introduced into the adsorption chamber with the help of the engine intake to recirculate the NO_x. The recirculation of NO_x also contributes to a reduction of the NO_x emission. In the present experiment, approximately 55% of the NO_x of the diesel exhaust (NO_x: 270-325 ppm, flow rate = 300 NL/min) can be continuously treated for 55 h. The energy efficiency of the system is calculated as 120 g (NO_2)/kWh with the combination of NTP and the NO_x recirculation.
