| 摘要 |
An exhaust gas purification system including a reducing agent supplying apparatus and an exhaust gas purification apparatus, in that order from an upstream side of an exhaust passage in an internal combustion engine, and a control unit for controlling an amount of reducing agent supplied into the exhaust gas to recover purification capability of the exhaust gas purification apparatus. A concentration of the reducing agent in the exhaust gas, which flows into the exhaust gas purification apparatus, is varied temporally. The reducing agent is supplied in a proper amount to efficiently recover the purification capability. At the same time, the outflow of the reducing agent to the downstream side of the exhaust gas purification apparatus can be prevented. |
