| 摘要 |
The present invention relates to a method for purifying the exhaust gas of an internal combustion engine, where nitrogen oxides within exhaust gas are converted by hydrocarbon which is measured and injected in a pulse form into an exhaust gas channel in front of a nitrogen oxide catalyst converter. According to the present invention, the concentration of hydrocarbon in the exhaust gas or the scale of the concentration is detected by a hydrocarbon sensor within the flow of the exhaust gas in back of the nitrogen oxide catalyst converter, and penetrates through the nitrogen oxide catalyst converter. Based on the concentration of hydrocarbon or the scale of the concentration detected by the hydrocarbon sensor, the measurement supply of hydrocarbon is affected in a method where the decomposition of hydrocarbon passing through the nitrogen oxide catalyst converter is prevented. In addition, the present invention relates to a device for performing the method above. The device and method optimally use the purifying action of hydrocarbon in relation to the used amount of the hydrocarbon during the removal of nitrogen oxides and enable the measurement and addition of hydrocarbon into exhaust gas of an internal combustion engine using a method for preventing the decomposition of unused hydrocarbon. |
