| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a compact and inexpensive exhaust emission control device while maintaining the purification efficiency of exhaust gas. <P>SOLUTION: An oxidation catalyst 108, a mixer 111, a DPF 112 and an SCR catalyst 113 are accommodated in a casing 104 of an exhaust emission control device 101 in this order from the upstream. An urea water injection nozzle 109 for adding urea water in exhaust gas is provided at the upstream of the oxidation catalyst 108. An urea water injection nozzle 110 is provided at the downstream of the oxidation catalyst 108. When an exhaust gas temperature is lower than a predetermined threshold, the urea water injection nozzle 109 is operated to add urea water into exhaust gas from the upstream of the oxidation catalyst 108. When the exhaust gas temperature is a predetermined threshold or higher, the urea water injection nozzle 110 is operated to add urea water into exhaust gas from the downstream of the oxidation catalyst 108. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
