Abstract: The invention relates to a method for monitoring an ammonia slip catalytic converter which is arranged in an exhaust gas after-treatment device of an internal combustion engine, downstream of a catalytic converter arrangement, wherein the method comprises the steps of measuring a nitrogen oxide content in the exhaust gas by means of a sensor upstream of the ammonia slip catalytic converter, detecting a sensor signal of an ammonia-cross-sensitive nitrogen oxide sensor which is arranged downstream of the ammonia slip catalytic converter, and checking whether the ammonia-cross-sensitive nitrogen oxide sensor measures a higher value than the sensor.

Abstract: Exhaust gas treatment system (100) for a motor vehicle, comprising a first catalytic converter (101-1) for selective catalytic reduction; a second catalytic converter (101-2) for selective catalytic reduction; a first nitrogen oxide sensor (103-1) upstream of the first catalytic converter (101-1) for detecting a first nitrogen oxide value (NOx-1); a second nitrogen oxide sensor (103-2) between the first and the second catalytic converter (101-1; 101-2) for detecting a second nitrogen oxide value (NOx-2); a third nitrogen oxide sensor (103-3) downstream of the second catalytic converter (101-2) for detecting a third nitrogen oxide value (NOx-3); an electronic evaluation device (105) for calculating a first efficiency of the first catalytic converter (101-1) on the basis of the first and the second nitrogen oxide value (NOx-1; NOx-2), a second efficiency of the second catalytic converter (101-2) on the basis of the second and the third nitrogen oxide value (NOx-2; NOx-3) and a total efficiency of the exhaust ga

Abstract: A correction method of NOx purifying efficiency of SDPF includes: measuring a temperature change per unit time inside the SDPF, determining whether the temperature change per unit time inside the SDPF is below a first predetermined value, determining whether a difference between a maximum value and a minimum value of temperature of respective parts inside the SDPF is below a second predetermined value if the temperature change per unit time inside the SDPF is below the first predetermined value, determining whether a temperature inside the SDPF is in a low temperature region if the difference between the maximum value and the minimum value of temperature of the respective parts inside the SDPF is below the second predetermined value, and performing a low temperature region correction if the temperature inside the SDPF is in the low temperature region.

Abstract: An exhaust gas purification system, which includes an engine and an exhaust pipe that is connected to an exhaust manifold of the engine, includes: a catalyst converter disposed at a rear side the engine on the exhaust pipe; a selective catalytic reduction on diesel particulate filter (SDPF) disposed at a rear side of the catalyst converter on the exhaust pipe; a reducing agent injector disposed between the catalyst converter and the SDPF on the exhaust pipe and injecting a reducing agent; and a controller controlling an amount of the reducing agent injected from the reducing agent injector.

Abstract: Provided is an exhaust purification system that may include: a first catalyst installed on a rear exhaust pipe of an engine; a selective catalytic reduction (SCR) catalyst installed on the rear exhaust pipe of the first catalyst; a reducing agent injector which is installed on an exhaust pipe between the first catalyst and the SCR catalyst and configured to inject a reducing agent; and a controller configured to control an amount of reducing agent injected from the reducing agent injector. /The controller may calculate a total amount of ammonia adsorbed in the SCR catalyst, a required amount of reducing agent based on a total amount of ammonia adsorbed in the SCR catalyst, and the amount of nitrogen oxide introduced into the SCR catalyst, and then control a reducing agent injector to inject the required amount of reducing agent.

Abstract: An exhaust gas purification system, which includes an engine and an exhaust pipe that is connected to an exhaust manifold of the engine, includes: a catalyst converter disposed at a rear side the engine on the exhaust pipe; a selective catalytic reduction on diesel particulate filter (SDPF) disposed at a rear side of the catalyst converter on the exhaust pipe; a reducing agent injector disposed between the catalyst converter and the SDPF on the exhaust pipe and injecting a reducing agent; and a controller controlling an amount of the reducing agent injected from the reducing agent injector.

Abstract: A correction method of NOx purifying efficiency of SDPF includes: measuring a temperature change per unit time inside the SDPF, determining whether the temperature change per unit time inside the SDPF is below a first predetermined value, determining whether a difference between a maximum value and a minimum value of temperature of respective parts inside the SDPF is below a second predetermined value if the temperature change per unit time inside the SDPF is below the first predetermined value, determining whether a temperature inside the SDPF is in a low temperature region if the difference between the maximum value and the minimum value of temperature of the respective parts inside the SDPF is below the second predetermined value, and performing a low temperature region correction if the temperature inside the SDPF is in the low temperature region.

Abstract: The invention relates to a method for monitoring an ammonia slip catalytic converter which is arranged in an exhaust gas after-treatment device of an internal combustion engine, downstream of a catalytic converter arrangement, wherein the method comprises the steps of measuring a nitrogen oxide content in the exhaust gas by means of a sensor upstream of the ammonia slip catalytic converter, detecting a sensor signal of an ammonia-cross-sensitive nitrogen oxide sensor which is arranged downstream of the ammonia slip catalytic converter, and checking whether the ammonia-cross-sensitive nitrogen oxide sensor measures a higher value than the sensor.

Abstract: Exhaust gas treatment system (100) for a motor vehicle, comprising a first catalytic converter (101-1) for selective catalytic reduction; a second catalytic converter (101-2) for selective catalytic reduction; a first nitrogen oxide sensor (103-1) upstream of the first catalytic converter (101-1) for detecting a first nitrogen oxide value (NOx-1); a second nitrogen oxide sensor (103-2) between the first and the second catalytic converter (101-1; 101-2) for detecting a second nitrogen oxide value (NOx-2); a third nitrogen oxide sensor (103-3) downstream of the second catalytic converter (101-2) for detecting a third nitrogen oxide value (NOx-3); an electronic evaluation device (105) for calculating a first efficiency of the first catalytic converter (101-1) on the basis of the first and the second nitrogen oxide value (NOx-1; NOx-2), a second efficiency of the second catalytic converter (101-2) on the basis of the second and the third nitrogen oxide value (NOx-2; NOx-3) and a total efficiency of the exhaust ga

Abstract: Provided is an exhaust purification system that may include : a first catalyst installed on a rear exhaust pipe of an engine; a selective catalytic reduction (SCR) catalyst installed on the rear exhaust pipe of the first catalyst; a reducing agent injector which is installed on an exhaust pipe between the first catalyst and the SCR catalyst and configured to inject a reducing agent; and a controller configured to control an amount of reducing agent injected from the reducing agent injector. / The controller may calculate a total amount of ammonia adsorbed in the SCR catalyst, a required amount of reducing agent based on a total amount of ammonia adsorbed in the SCR catalyst, and the amount of nitrogen oxide introduced into the SCR catalyst, and then control a reducing agent injector to inject the required amount of reducing agent.