| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust emission cleaning device capable of both eliminating NOx and HC and reducing the amount of NO generation without adding a special additive such as alcohol to exhaust gas.SOLUTION: The exhaust emission clearing device includes a first oxidation catalyst for oxidizing HC in exhaust gas, a NOx removal catalyst provided on the downstream side of the first oxidation catalyst for reducing NOx in the exhaust gas with NH, a temperature sensor for detecting the temperature of the exhaust gas, and a NO reduction mode executing unit capable of executing a NO reduction mode to reduce an amount of NO generation in the exhaust emission clearing device. In the NO reduction mode, the NO reduction mode executing unit reduces an amount of NOx exhaust when the temperature of the exhaust gas is equal to or higher than a reference temperature, and reduces the amount of HC exhaust when the temperature of the exhaust gas is lower than the reference temperature.SELECTED DRAWING: Figure 4 |
