| 摘要 |
PROBLEM TO BE SOLVED: To enhance modification of a fuel used as a reducing agent.SOLUTION: A reducing agent addition device includes fuel addition control means, ozone addition control means, and air increase control means. The fuel addition control means produces modified fuel by operating a fuel injection valve, a heater and an ozonizer, and operates the reducing agent addition device in a modified fuel mode for adding the modified fuel to an exhaust passage as a reducing agent. The ozone addition control means operates the reducing agent addition device in an ozone mode for producing ozone by operating the ozonizer while stopping the operation of the fuel injection valve and the heater. The air increase control means increases an air flow rate to the ozonizer in a case when an internal temperature of the ozonizer becomes high temperature over upper limit values Tu1, Tu2. The upper limit value Tu2 in the modified fuel mode is determined to be a value higher than the upper limit value Tu1 in the ozone mode. |
