| 摘要 |
A method of deciding on catalyst deterioration in an exhaust gas decontamination system, which method enables making an accurate decision on the state of deterioration of catalyst caused by sulfur poisoning in a NOx purging system using a direct reduction type NOx catalyst in the purging of NOx from exhaust gas. In particular, a method of deciding on catalyst deterioration in a NOx purging system (10) comprising exhaust gas passage (2) and, arranged therein, direct reduction type NOx catalyst (3), wherein when the operating condition of engine (1) is within a deterioration decision zone and is of stationary operation, an exhaust gas for decision is generated and wherein when the concentration of NOx in exhaust gas (Cnox) resulting from pass of the exhaust gas for decision through the direct reduction type NOx catalyst (3) is not below given decision level (Cnoxlim), the direct reduction type NOx catalyst (3) is judged as being deteriorated.
|
