Multipoint barrier discharge process for removal of NOx from diesel engineexhaust

We investigated the application of the dielectric barrier discharge process to the removal of NOx from exhaust gas of a 20-kVA diesel engine generator . A multipoint-to-plane geometry was used as an electrode for low-voltage o peration. A pyrex glass plate with a 2-mm thickness was put on the plane el ectrode as the dielectric barrier The reactor consists of six discharge cel ls, with each cell consisting of five stacked multipoint-to-plane electrode s where the exhaust gas flows with a high flow rate. The exhaust gas was su ccessfully treated at a flow rate of 1.2 m(3)/min. In order to produce repe titive high-voltage pulse, we made two switching electronic devices, an ins ulated gate bipolar transistor (IGBT), and a pulse transformer. This pulse modulator supplied the voltage with peak value of 10 kV and repetition rate of 2.5 kp/s (pulses per second) to the reactor. The energy transfer effici ency of the pulse modulator is 65% at 300 W of the power consumed in the re actor. The NOx (NO + NO2) in the exhaust gas was reduced by 35 ppm with an electrical efficiency of 32 g/kWh.