| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an emission control system in which an NOx control function and a PM control function are combined, and an emission control method, wherein the optimum NOx control rate can be maintained in a continuously regenerable range of the DPF. <P>SOLUTION: The emission control system 1 executes NOx control by NOx occlusion reduction catalyst 42 and PM control by continuous regeneration type DPF 41 with respect to exhausting gas of an internal combustion engine. In a catalyst regeneration control for regenerating the NOx occlusion reduction catalyst 42 when the temperature Tent of an exhaust gas flown in the DPF 41b is not less than the self combustion temperature Tent0 and the differential pressure increase rate dP0 of pressure difference across the DPF 41b is not less than the prescribed criterion value, at least either of controls for reducing frequency to enrich exhaust gas and for making enrichment shallow is carried out. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
