| 摘要 |
In an exhaust gas purification system for an internal combustion engine provided with a particulate filter and an SCR catalyst arranged downstream of the particulate filter, the present invention is intended to decrease an amount of NOx discharged into the atmosphere in a suitable manner. According to the present invention, in an exhaust gas purification system for an internal combustion engine provided with a particulate filter, an SCR catalyst arranged downstream of the particulate filter, a reducing agent supply device and an EGR device, when the temperature of the particulate filter is equal to or higher than a PM oxidation starting temperature, and when an amount of PM trapped in the particulate filter is equal to or less than an upper limit amount, an amount of EGR gas is made to increase, whereas when the temperature of the particulate filter belongs to a temperature range in which oxidation reduction reaction of NO 2 and PM is promoted, and when the temperature of the SCR catalyst belongs to an NOx reduction window, an amount of NO 2 in exhaust gas is made to increase. |
