| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust treatment device for an engine that can perform reproduction processing of a DPF even immediately after the start of the engine or during light-load operation, and can suppress a functional decrease of a combustion catalyst.SOLUTION: When the temperature of exhaust 6 is lower than a predetermined reference exhaust temperature during reproduction treatment of a DPF 7, a control device 11 performs low temperature-time gas ignition treatment so as to ignite an inflammable gas 2 by an electrothermal ignition device 10 and to supply heat of flame combustion of the inflammable gas 2 to an exhaust passage 4 in the low temperature-time gas ignition treatment. When a predetermined amount of PM is deposited on a combustion catalyst 5, the control means 11 performs reproduction treatment of the combustion catalyst 5 so as to generate an inflammable gas 2 by an inflammable gas generator 1. The inflammable gas 2 is ignited by the electrothermal ignition device 10 and heat of flame combustion of the inflammable gas 2 is supplied to the exhaust passage 4. The entrance exhaust temperature of the combustion catalyst 5 is thereby made higher than that in the low temperature-time gas ignition treatment so as to burn away the PM deposited on the combustion catalyst 5. |
