| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of controlling an exhaust emission control device capable of preventing NOx storage/reduction catalyst from being deteriorated by the poison of a sulfate, capable of avoiding the lowering of an NOx purification factor by the NOx storage/reduction catalyst and extending the life of the catalyst, and capable of efficiently and securely separating the sulfate from a particulate filter and decomposing and discharging the sulfate and a nitrate from the NOx storage/reduction catalyst by the addition of the minimum required HC without performing difficult operational control on the diesel engine side. <P>SOLUTION: The particulate filter 12, the NOx storage/reduction catalyst 11, and a bypass line 17 bypassing the NOx storage/reduction catalyst 11 are installed in an exhaust pipe 9, a selector valve 18 is installed at the branch part of the exhaust pipe, and an HC adding device 19 is installed at the inlet side of the NOx storage/reduction catalyst 11. Thus, the temperature raising control of the particulate filter 12, the switching of the selector valve 18, and the HC adding control by the HC adding device 19 can be properly performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
