| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrict clogging of an NOx storage reduction type catalyst disposed on the downstream side, and further improve NOx emission control performance by promoting vaporization of liquid reducing agent. <P>SOLUTION: A vaporization promoting means 5 is disposed to promote vaporization of liquid reducing agent added between a turbo charger 2 and an injector 12, and the NOx storage reduction type catalyst is disposed downstream of the turbo charger 2. Vaporization of liquid reducing agent added from the injector 12 is promoted by the vaporization promoting means 5, so that attachment of liquid reducing agent to an upstream side end surface of the NOx storage reduction type catalyst can be restricted. Attachment of PM to it to clog a cell passage is also restricted, and increase of exhaust pressure loss can be restricted. Since utilization factor at an upstream side end part of the NOx storage reduction type catalyst is improved, NOx emission control performance is also improved. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
