| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress hydrocarbon emission into the atmosphere by certainly catching hydrocarbon even if the flow speed of the hydrocarbon injected from an injection nozzle is increased at once by a sudden increase in exhaust gas pressure. <P>SOLUTION: A particulate filter 23 is provided in the exhaust pipe 16 of a diesel engine 11 with a turbosupercharger 17, a first oxidation catalyst 31 is provided in the exhaust pipe on the exhaust gas upstream side of the filter, and a first selective reduction catalyst 41 is provided in the exhaust pipe on the exhaust gas upstream side of the first oxidation catalyst. A hydrocarbon liquid adding means 26 has an injection nozzle 26a inserted into the exhaust pipe provided on the exhaust gas upstream side of the first selective reduction catalyst, and injects hydrocarbon liquid 26d from the injection nozzle toward the first selective reduction catalyst. A controller 29 controls the hydrocarbon liquid adding means based on a detected result from an operating state detection means 28 detecting the operating state of the engine. A second selective reduction catalyst 42 is provided in the exhaust pipe on the exhaust gas downstream side of the particulate filter. <P>COPYRIGHT: (C)2011,JPO&INPIT |
