| CPC F01N 3/208 (2013.01) [B01D 53/944 (2013.01); B01D 53/9418 (2013.01); B01D 53/9436 (2013.01); B01D 53/9495 (2013.01); B01J 19/0013 (2013.01); B01J 19/0033 (2013.01); B01J 19/245 (2013.01); F01N 3/035 (2013.01); F01N 3/106 (2013.01); F01N 13/0093 (2014.06); F02D 41/0245 (2013.01); B01J 2219/00162 (2013.01); B01J 2219/00182 (2013.01); F01N 2610/1406 (2013.01); F01N 2610/1433 (2013.01); F01N 2610/1453 (2013.01); F01N 2900/1402 (2013.01); F01N 2900/1404 (2013.01)] | 9 Claims |
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1. An exhaust gas after-treatment system comprising:
an exhaust flow path configured to move exhaust gas discharged from an engine;
a first reactor installed in the exhaust flow path and embedded with a catalyst for reducing the amount of nitrogen oxide contained in the exhaust gas;
a second reactor installed in the exhaust flow path, disposed at a downstream side from the first reactor, and embedded with a catalyst for reducing the amount of nitrogen oxide contained in the exhaust gas;
a first reducing agent injection unit configured to inject a reducing agent toward the exhaust gas to be introduced into the first reactor;
a second reducing agent injection unit configured to inject the reducing agent toward the exhaust gas to be introduced into the second reactor;
a reducing agent supply unit configured to supply the reducing agent to the first and second reducing agent injection units;
a first temperature sensor configured to measure a temperature of the exhaust gas to be introduced into the first reactor;
a second temperature sensor configured to measure a temperature of the exhaust gas to be introduced into the second reactor; and
a control device configured to control whether to inject the reducing agent from the first and second reducing agent injection units and the amount of reducing agent to be injected on the basis of temperature information provided by the first and second temperature sensors,
wherein the control device adjusts the temperature of the exhaust gas to be discharged from the engine by controlling an operational condition of the engine,
wherein the control device raises the temperature of the exhaust gas by controlling the engine when the temperature of the exhaust gas measured by the first temperature sensor is lower than a first reference temperature,
wherein
the control device injects the reducing agent from the first reducing agent injection unit while raising the temperature of the exhaust gas by controlling the engine when the temperature of the exhaust gas measured by the first temperature sensor is higher than a second reference temperature according to the performance of the catalyst contained in the first reactor and the second reactor and the temperature of the exhaust gas measured by the second temperature sensor is lower than a third reference temperature set higher than the second reference temperature, and
the control device injects the reducing agent from the first and second reducing agent injection units when the temperature of the exhaust gas measured by the first temperature sensor is higher than the second reference temperature and the temperature of the exhaust gas measured by the second temperature sensor is higher than the third reference temperature, and
wherein
the first reference temperature is preset in a range of higher than 150° C. and lower than 200° C.,
the second reference temperature is preset higher than the first reference temperature in a range of 200° C. to 500° C., and
the third reference temperature is preset higher than the second reference temperature in a range of 250° C. to 600° C.
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