Abstract: A method for desulphurising a nitrogen oxide accumulator catalytic converter of an exhaust gas system that includes the nitrogen oxide accumulator catalytic converter and at least one selective catalytic reduction catalytic converter disposed downstream of the nitrogen oxide accumulator catalytic converter, of an internal combustion engine, where a desulphurisation strategy, on the basis of which the nitrogen oxide accumulator catalytic converter is desulphurised, is adjusted to the ageing of the nitrogen oxide accumulator catalytic converter.

Abstract: A method for operating an exhaust system of an internal combustion engine of a motor vehicle, in which exhaust gas from the internal combustion engine flows through a first SCR catalytic converter, which is followed by an ammonia barrier catalytic converter, and flows through a second SCR catalytic converter which is disposed downstream of the ammonia barrier catalyst, includes introducing a reducing agent introduced into the exhaust gas by a first metering device upstream of the first SCR catalytic converter and by a second metering device upstream of the second SCR catalytic converter. When a predetermined threshold value of a temperature of a region of the exhaust system is exceeded, a quantity of reducing agent introduced into the exhaust gas by the first metering device is increased.

Abstract: A method for desulphurising a nitrogen oxide accumulator catalytic converter of an exhaust gas system that includes the nitrogen oxide accumulator catalytic converter and at least one selective catalytic reduction catalytic converter disposed downstream of the nitrogen oxide accumulator catalytic converter, of an internal combustion engine, where a desulphurisation strategy, on the basis of which the nitrogen oxide accumulator catalytic converter is desulphurised, is adjusted to the ageing of the nitrogen oxide accumulator catalytic converter.

Abstract: A method for operating an exhaust system, where the exhaust system has a first selective catalytic reduction (SCR) catalytic converter close to the engine and a second SCR catalytic converter arranged downstream of the first. A respective quantity of reducing agent to be introduced into the exhaust gas by a respective dosing element is set depending on a first temperature of the first SCR catalytic converter, where during a period of time during which the first temperature exceeds a predeterminable first threshold value and a second temperature of the second SCR catalytic converter exceeds a predeterminable second threshold value, which is lower than the first threshold value, the introduction of the reducing agent into the exhaust gas with regard to the dosing elements takes place exclusively via the second dosing element such that during the period of time, no introduction of the reducing agent into the exhaust gas takes place.

Abstract: A method for operating an internal combustion engine of a motor vehicle, which has an exhaust gas system that exhaust gas from at least one combustion chamber of the internal combustion chamber can flow through and includes at least one nitrogen oxide storage catalyst, at least one particulate filter, and at least one selective catalytic reduction (SCR) catalyst.

Abstract: A method for operating an exhaust system of an internal combustion engine of a motor vehicle, in which exhaust gas from the internal combustion engine flows through a first SCR catalytic converter, which is followed by an ammonia barrier catalytic converter, and flows through a second SCR catalytic converter which is disposed downstream of the ammonia barrier catalyst, includes introducing a reducing agent introduced into the exhaust gas by a first metering device upstream of the first SCR catalytic converter and by a second metering device upstream of the second SCR catalytic converter. When a predetermined threshold value of a temperature of a region of the exhaust system is exceeded, a quantity of reducing agent introduced into the exhaust gas by the first metering device is increased.

Abstract: A method for operating an exhaust system, where the exhaust system has a first selective catalytic reduction (SCR) catalytic converter close to the engine and a second SCR catalytic converter arranged downstream of the first. A respective quantity of reducing agent to be introduced into the exhaust gas by a respective dosing element is set depending on a first temperature of the first SCR catalytic converter, where during a period of time during which the first temperature exceeds a predeterminable first threshold value and a second temperature of the second SCR catalytic converter exceeds a predeterminable second threshold value, which is lower than the first threshold value, the introduction of the reducing agent into the exhaust gas with regard to the dosing elements takes place exclusively via the second dosing element such that during the period of time, no introduction of the reducing agent into the exhaust gas takes place.

Abstract: A method for operating an internal combustion engine of a motor vehicle, which has an exhaust gas system that exhaust gas from at least one combustion chamber of the internal combustion chamber can flow through and includes at least one nitrogen oxide storage catalyst, at least one particulate filter, and at least one selective catalytic reduction (SCR) catalyst.

Abstract: A method for adjusting the temperature of an exhaust gas aftertreatment device is disclosed. A first characteristic temperature value for an oxidative carbon monoxide conversion and a second characteristic temperature value for an oxidative hydrocarbon conversion are assigned to an oxidation catalytic converter, and a third characteristic temperature value for a reductive NOx conversion is assigned to an SCR catalytic converter. Different respective values for injection parameters of injection processes for fuel injections into combustion chambers of the internal combustion engine and/or the heating output of an electric heating element are set upon reaching the first and the second characteristic temperature values for the temperature of the oxidation catalytic converter and upon reaching the third characteristic temperature value for the temperature of the SCR catalytic converter.

Abstract: A method and device for monitoring the formation of nitrogen dioxide at an oxidation catalytic converter is disclosed. The conversion of the nitrogen oxides, corresponding to a first exhaust gas volume flowrate through the oxidation catalytic converter, is detected. The exhaust gas volume flowrate is then changed and the conversion of the nitrogen oxides which changes with the change in the exhaust gas volume flowrate is also detected. By reference to the respective conversion of the nitrogen oxides at the different exhaust gas flowrates through the oxidation catalytic converter, it is concluded, on the basis of a predetermined relationship between the conversion of the nitrogen oxides and a proportion of nitrogen dioxide in the nitrogen oxides in the exhaust gas, that nitrogen dioxide is being formed at the oxidation catalytic converter.

Abstract: A method for determining a soot load on a particle filter provided with a selective catalytic coating is disclosed. The method includes determining a nitric oxide conversion on the particle filter and determining a soot load on the particle filter from the determined nitric oxide conversion.

Abstract: A system for exhaust gas routing and aftertreatment in a motor vehicle includes a first exhaust gas duct element, which has an inlet opening and an outlet opening, and a second exhaust gas duct element, which has a transfer pipe having a longitudinal axis and having a sleeve surface and a first closed end. An intake opening is provided in the sleeve surface adjacent to the closed end. The transfer pipe projects into the outlet opening and is accommodated in the first exhaust gas duct element by its closed end and the intake opening, so that exhaust gas flowing in through the inlet opening in a first direction can flow through the intake opening and into the transfer pipe and flow—viewed in the direction of the longitudinal axis of the transfer pipe—in the transfer pipe through the outlet opening out of the first exhaust gas duct element.

Abstract: A method for operating an exhaust gas system of a motor vehicle involves performing regeneration of the particle filter as a function of at least one aging value characterizing an aging condition of the oxidation catalytic converter.

Abstract: A method for operating a motor vehicle internal combustion engine that has an exhaust tract with an exhaust gas purification unit acting catalytically and/or by filtration with which combustion air supplemented by exhaust gas diverging from the exhaust tract is fed to the combustion chambers of the internal combustion engine by exhaust gas branching off from the exhaust tract at a total exhaust gas recirculation rate. The total exhaust gas recirculation rate has a low-pressure proportion diverging downstream from the exhaust gas purification unit and a high-pressure proportion diverging upstream from an exhaust gas turbocharger turbine arranged in the exhaust tract. An essentially decreasing low pressure proportion is set with at least approximately the same operating points of the internal combustion engine with an increasing operating period of the exhaust gas purification unit.

Abstract: A method for operating an internal combustion engine having an exhaust emission control unit with at least one exhaust emission control component which acts catalytically and/or by filtration involves operating the internal combustion engine, during a cold start or warm-up of the internal combustion engine, using a cold start engine operating process with predefined values for predefined internal combustion engine operating variables. The cold start and/or the warm-up of the internal combustion engine is controlled or regulated as a function of soot loading of a particle filter of the exhaust emission control unit.

Abstract: A method for operating a motor vehicle diesel engine having an exhaust emission control system is provided. The emission control system includes an oxidation catalytic converter, a particle filter, and an SCR catalytic converter, in which the exhaust gas that is discharged from the diesel engine is passed through the oxidation catalytic converter before passing through the particle filter and the SCR catalytic converter. A regeneration of the particle filter with thermal soot burn-off is occasionally carried out, during which the diesel engine is operated at an air-fuel ratio having a lambda value (?) of at least approximately 1.0, and air is added to the exhaust gas after it exits the oxidation catalytic converter and before it enters the particle filter air, so that soot deposited on the particle filter is burnt-off.

Abstract: A method and device for monitoring the formation of nitrogen dioxide at an oxidation catalytic converter is disclosed. The conversion of the nitrogen oxides, corresponding to a first exhaust gas volume flowrate through the oxidation catalytic converter, is detected. The exhaust gas volume flowrate is then changed and the conversion of the nitrogen oxides which changes with the change in the exhaust gas volume flowrate is also detected. By reference to the respective conversion of the nitrogen oxides at the different exhaust gas flowrates through the oxidation catalytic converter, it is concluded, on the basis of a predetermined relationship between the conversion of the nitrogen oxides and a proportion of nitrogen dioxide in the nitrogen oxides in the exhaust gas, that nitrogen dioxide is being formed at the oxidation catalytic converter.

Abstract: A system for exhaust gas routing and aftertreatment in a motor vehicle includes a first exhaust gas duct element, which has an inlet opening and an outlet opening, and a second exhaust gas duct element, which has a transfer pipe having a longitudinal axis and having a sleeve surface and a first closed end. An intake opening is provided in the sleeve surface adjacent to the closed end. The transfer pipe projects into the outlet opening and is accommodated in the first exhaust gas duct element by its closed end and the intake opening, so that exhaust gas flowing in through the inlet opening in a first direction can flow through the intake opening and into the transfer pipe and flow—viewed in the direction of the longitudinal axis of the transfer pipe—in the transfer pipe through the outlet opening out of the first exhaust gas duct element.

Abstract: A method for operating an exhaust gas system of a motor vehicle involves performing regeneration of the particle filter as a function of at least one aging value characterizing an aging condition of the oxidation catalytic converter.

Abstract: A method for operating an internal combustion engine having an exhaust emission control unit with at least one exhaust emission control component which acts catalytically and/or by filtration involves operating the internal combustion engine, during a cold start or warm-up of the internal combustion engine, using a cold start engine operating process with predefined values for predefined internal combustion engine operating variables. The cold start and/or the warm-up of the internal combustion engine is controlled or regulated as a function of soot loading of a particle filter of the exhaust emission control unit.