Automatic Control Method of NO Removal by a Combination of Ozone Injection and Exhaust Gas Recirculation

NO_x from diesel exhaust gases can efficiently be removed by a combination of ozone injection and exhaust gas recirculation (EGR). To industrialize the system, it is necessary to develop a NO control system because the NO concentration largely changes by an engine output power. In this paper, we constructed a NO control system without using any sensor. As for the control method, we adopted two control methods: 1) an ozone control under a predetermined rate of the EGR and 2) an energy minimum control. The details of the automatic control methods are introduced in this paper. NO control experiments were carried out using a 2.4-kVA diesel engine generator, and the NO emissions were successfully controlled by the system.