| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately estimate a catalyst temperature during catalyst regeneration processing in accordance with an injection pattern of a cylinder injector.SOLUTION: An exhaust emission control system includes: an exhaust aftertreatment device 30 having an NOx catalyst 32 arranged therein; an SOx purge control section 60 that performs catalyst regeneration processing for removing SOx adsorbed to the NOx catalyst 32 by increasing an exhaust gas temperature through exhaust rich injection; discharge amount storage sections 86A-87B that acquire and store beforehand the amounts of HC and CO discharged from an internal combustion engine 10 during execution of the catalyst regeneration processing with respect to each injection pattern of a cylinder injector 11; heat generation amount estimation sections 88A, B that estimate HC and CO heat generation amounts of the NOx catalyst 32 on the basis of the amounts of HC and CO read from the discharge amount storage sections 86A-87B in accordance with the multiple injection patterns during execution of the catalyst regeneration processing; and catalyst temperature estimation sections 88C, D that estimate a catalyst temperature during execution of the catalyst regeneration processing on the basis of the HC and CO heat generation amounts estimated by the heat generation amount estimation sections 88A, B.SELECTED DRAWING: Figure 10 |
