| 摘要 |
<P>PROBLEM TO BE SOLVED: To effectively reduce NOx in an operation state of the low exhaust temperature, by utilizing an oxidation catalyst carried on a particulate filter and an oxidation catalyst arranged in its front stage. <P>SOLUTION: This exhaust emission control device is provided for forcibly regenerating the particulate filter 13 by reaction heat when its adding fuel causes oxidation reaction on the oxidation catalyst 14, by adding the fuel by post-injection on the diesel engine 1 side, by interposing the catalytic regeneration type particulate filter 13 equipped with the oxidation catalyst 14 in the front stage in an exhaust pipe 11, and is constituted so that an NO<SB>2</SB>generating catalyst 22 for promoting the oxidation reaction of NO to NO<SB>2</SB>is arranged in the exhaust pipe 11 on the upstream side of the oxidation catalyst 14, and a fuel adding device 23 is arranged for directly injecting the fuel into exhaust gas 9 between the NO<SB>2</SB>generating catalyst 22 and the oxidation catalyst 14, and a part of the exhaust gas 9 is extracted from an exhaust system on the upstream side of the fuel adding device 23, and is recirculated to an intake system. <P>COPYRIGHT: (C)2009,JPO&INPIT |
