| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of supplying urea water to a NOx catalyst selectively reducing NOx in exhaust gas with using ammonia as reducing agent without clogging. <P>SOLUTION: This device is provided with the NOx catalyst 30 selectively reducing NOx with using ammonia as reducing agent, an urea water injection device 42 mixing urea water into pressurized air supplied via an air supply passage 46 and supplying the same to an urea water adding nozzle 38 via an urea water injection passage 40, and a washing water supply means 54, 60 supplying washing water to the urea water injection device 42, and controls the washing water supply means 54, 60 based on one or both of inner pressure in the air supply passage 46 and the urea water injection passage 40. <P>COPYRIGHT: (C)2007,JPO&INPIT |
