Abstract: A motor vehicle combustion engine includes an air supply section and an exhaust gas recirculation section that includes a particle filter and an SCR exhaust gas purification component. A first exhaust gas turbocharger includes a turbine arranged upstream of the particle filter in the exhaust gas section. A first exhaust gas recirculation line, which diverges from the exhaust gas section upstream of the turbine of the first exhaust gas turbocharger, and a second exhaust gas recirculation line, which diverges from the exhaust gas section downstream of the particle filter are provided to recirculate the exhaust gas from the exhaust gas section into the air supply system. An SCR catalyst is arranged in the second exhaust gas recirculation line.

Abstract: In a method for reducing the emission of nitrogen dioxide in a motor vehicle having an exhaust gas purification system having an SCR catalytic converter with adsorption centers for nitrogen oxides, an exhaust gas enriched with ammonia is supplied to the SCR catalytic converter above an operating temperature. Below the operating temperature, the exhaust gas supplied to the SCR catalytic converter is enriched with a material such that an adsorption of nitrogen oxides is inhibited at corresponding adsorption centers of the SCR catalytic converter. In order to reduce the overall NOx emissions below a first, predeterminable amount, an exhaust gas enriched with ammonia is supplied to the SCR catalytic converter and the NO2 portion of the total NOx emissions is reduced below a second, predeterminable amount in that NO2 is converted with hydrocarbons stored in the SCR catalytic converter.

Abstract: In a method for operating an air-compressing fuel-injection internal combustion engine having an exhaust gas post-treatment system with a particle filter and a nitrogen oxide reduction catalytic converter, a plurality of internal combustion engine operating settings are provided, each having respective predefined values for predefined internal combustion engine operating parameters. A heating operating setting is set when the internal combustion engine is warming up, while a basic operating setting is set in the warmed-up state. When the temperature in the exhaust gas system exceeds a predefinable first value, the heating operating setting is changed over to the basic operating setting. In the warmed-up state, at least one further (third) operating setting, with an exhaust gas recirculation rate that is reduced compared to the basic operating setting, is provided in addition to the basic operating setting.

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: An operating method is provided for a motor vehicle diesel engine having an exhaust emission control system that includes a three-way catalytic converter and an SCR catalytic converter situated one behind the other in the flow direction of the exhaust gas. The diesel engine is operated, at least intermittently, with an air-fuel ratio of approximately ?=1.0 in a first operating range in which the SCR catalytic converter falls below a predefinable minimum temperature and with excess air that is typical for normal diesel engine operation in a second operating range in which the SCR catalytic converter exceeds the predefinable minimum temperature. An output signal of an exhaust gas sensor situated downstream from the three-way catalytic converter and which is correlated with a NOx concentration of the exhaust gas is used to set the air-fuel ratio in the first operating range.

Abstract: A motor vehicle combustion engine includes an air supply section and an exhaust gas recirculation section that includes a particle filter and an SCR exhaust gas purification component. A first exhaust gas turbocharger includes a turbine arranged upstream of the particle filter in the exhaust gas section. A first exhaust gas recirculation line, which diverges from the exhaust gas section upstream of the turbine of the first exhaust gas turbocharger, and a second exhaust gas recirculation line, which diverges from the exhaust gas section downstream of the particle filter are provided to recirculate the exhaust gas from the exhaust gas section into the air supply system. An SCR catalyst is arranged in the second exhaust gas recirculation line.

Abstract: In a method for operating an air-compressing fuel-injection internal combustion engine having an exhaust gas post-treatment system with a particle filter and a nitrogen oxide reduction catalytic converter, a plurality of internal combustion engine operating settings are provided, each having respective predefined values for predefined internal combustion engine operating parameters. A heating operating setting is set when the internal combustion engine is warming up, while a basic operating setting is set in the warmed-up state. When the temperature in the exhaust gas system exceeds a predefinable first value, the heating operating setting is changed over to the basic operating setting. In the warmed-up state, at least one further (third) operating setting, with an exhaust gas recirculation rate that is reduced compared to the basic operating setting, is provided in addition to the basic operating setting.

Abstract: The exhaust gas aftertreatment device according to the invention having a reforming unit for generating hydrogen by steam reforming, partial oxidation of hydrocarbons and/or mixed forms thereof is distinguished by the fact that the reforming unit is arranged directly in the main exhaust gas stream from an internal combustion engine. The steam and residual oxygen which are required for the reforming preferably originate from the exhaust gas. The step of providing the required reducing agents consists in briefly switching the internal combustion engine, which is predominantly operated in lean-burn mode and the exhaust gas from which is undergoing the aftertreatment, to rich-burn mode, allowing reforming by means of the reforming reactor according to the invention using the hydrocarbons that are present in the exhaust gas.

Abstract: In a method for operating an air-compressing fuel-injection internal combustion engine having an exhaust gas post-treatment system with a particle filter and a nitrogen oxide reduction catalytic converter, a plurality of internal combustion engine operating settings are provided, each having respective predefined values for predefined internal combustion engine operating parameters. A heating operating setting is set when the internal combustion engine is warming up, while a basic operating setting is set in the warmed-up state. When the temperature in the exhaust gas system exceeds a predefinable first value, the heating operating setting is changed over to the basic operating setting. In the warmed-up state, at least one further (third) operating setting, with an exhaust gas recirculation rate that is reduced compared to the basic operating setting, is provided in addition to the basic operating setting.

Abstract: In a method for operating an air-compressing fuel-injection internal combustion engine having an exhaust gas post-treatment system with a particle filter and a nitrogen oxide reduction catalytic converter, a plurality of internal combustion engine operating settings are provided, each having respective predefined values for predefined internal combustion engine operating parameters. A heating operating setting is set when the internal combustion engine is warming up, while a basic operating setting is set in the warmed-up state. When the temperature in the exhaust gas system exceeds a predefinable first value, the heating operating setting is changed over to the basic operating setting. In the warmed-up state, at least one further, (third) operating setting, with an exhaust gas recirculation rate that is reduced compared to the basic operating setting, is provided in addition to the basic operating setting.

Abstract: In a device and a method for removing nitrogen oxides from the exhaust of an internal combustion engine which is operated predominantly with an excess of air, the internal combustion engine is assigned an exhaust system having a nitrogen oxide reduction catalytic converter which comprises two catalytic converter parts, whose reducing agent filling levels can be determined. Metering of a reducing-agent-containing additive into the exhaust gas of the internal combustion engine takes place as a function of the reducing agent filling level of the first catalytic converter part and/or of the second catalytic converter part.

Abstract: In a method for reducing the emission of nitrogen dioxide in a motor vehicle having an exhaust gas purification system having an SCR catalytic converter with adsorption centers for nitrogen oxides, an exhaust gas enriched with ammonia is supplied to the SCR catalytic converter above an operating temperature. Below the operating temperature, the exhaust gas supplied to the SCR catalytic converter is enriched with a material such that an adsorption of nitrogen oxides is inhibited at corresponding adsorption centers of the SCR catalytic converter. In order to reduce the overall NOx emissions below a first, predeterminable amount, an exhaust gas enriched with ammonia is supplied to the SCR catalytic converter and the NO2 portion of the total NOx emissions is reduced below a second, predeterminable amount in that NO2 is converted with hydrocarbons stored in the SCR catalytic converter.

Abstract: An exhaust gas purification system for a motor vehicle having a reducing agent storage tank, and an associated operating method. In particular, an exhaust gas purification system for a motor vehicle, for which predetermined maintenance intervals is provided. The system includes a reducing agent storage tank for storing a reducing agent intended for exhaust gas purification. A method for operating a motor vehicle having an exhaust gas purification system and a reducing agent storage tank for storing a reducing agent intended for the exhaust gas purification, which comprises predetermined maintenance work after predetermined maintenance intervals is also provided.

Abstract: A device for monitoring an exhaust gas catalytic converter in the exhaust system of an internal combustion engine, includes a measuring apparatus that is arranged in the exhaust system in such a way that, in the greatest part of the operating range of the internal combustion engine, it assumes a temperature that is correlated with a temperature of the exhaust gas catalytic converter. The measuring apparatus has a temperature-sensitive component with a temperature-dependent characteristic component parameter that changes either abruptly at a predetermined transition temperature or temperature range, or continuously in a predetermined way as a function of the temperature. A control and evaluation unit connected to the measuring arrangement detects the characteristic component parameter and/or a change in the latter, and correlates it with an aging state of the exhaust gas catalytic converter.

Abstract: In a method for operating an air-compressing fuel-injection internal combustion engine having an exhaust gas post-treatment system with a particle filter and a nitrogen oxide reduction catalytic converter, a plurality of internal combustion engine operating settings are provided, each having respective predefined values for predefined internal combustion engine operating parameters. A heating operating setting is set when the internal combustion engine is warming up, while a basic operating setting is set in the warmed-up, while a basic operating setting is set in the warmed-up state. When the temperature in the exhaust gas system exceeds a predefinable first value, the heating operating setting is changed over to the basic operating setting. In the warmed-up state, at least one further, (third) operating setting, with an exhaust gas recirculation rate that is reduced compared to the basic operating setting, is provided in addition to the basic operating setting.

Abstract: In a device and a method for removing nitrogen oxides from the exhaust of an internal combustion engine which is operated predominantly with an excess of air, the internal combustion engine is assigned an exhaust system having a nitrogen oxide reduction catalytic converter which comprises two catalytic converter parts, whose reducing agent filling levels can be determined. Metering of a reducing-agent-containing additive into the exhaust gas of the internal combustion engine takes place as a function of the reducing agent filling level of the first catalytic converter part and/or of the second catalytic converter part.

Abstract: An exhaust gas purification system for a motor vehicle having a reducing agent storage tank, and an associated operating method. In particular, an exhaust gas purification system for a motor vehicle, for which predetermined maintenance intervals is provided. The system includes a reducing agent storage tank for storing a reducing agent intended for exhaust gas purification. A method for operating a motor vehicle having an exhaust gas purification system and a reducing agent storage tank for storing a reducing agent intended for the exhaust gas purification, which comprises predetermined maintenance work after predetermined maintenance intervals is also provided.

Abstract: in a method for operating a supercharged internal combustion engine and an internal combustion engine including an exhaust gas treatment system which comprises a catalytic converter arranged close to the engine, an exhaust gas turbocharger which is arranged downstream of the catalytic converter, and a post-injection device for introducing additional fuel into the exhaust gas flow upstream of the catalytic converter, wherein the heat energy of the exhaust gas mass flow which acts on the exhaust gas turbocharger is varied by controlling the fuel quantity which is additionally introduced into the exhaust gas flow by means of the post-injection device resulting in an improvement in the response behavior of the internal combustion engine, excess energy which is generated by the exhaust gas turbocharger by means of a motor generator connected to the exhaust gas turbocharger is stored in a storage device and is returned to the motor generator for rapidly accelerating the turbocharger when an increased power output i

Abstract: The exhaust gas aftertreatment device according to the invention having a reforming unit for generating hydrogen by steam reforming, partial oxidation of hydrocarbons and/or mixed forms thereof is distinguished by the fact that the reforming unit is arranged directly in the main exhaust gas stream from an internal combustion engine. The steam and residual oxygen which are required for the reforming preferably originate from the exhaust gas. The step of providing the required reducing agents consists in briefly switching the internal combustion engine, which is predominantly operated in lean-burn mode and the exhaust gas from which is undergoing the aftertreatment, to rich-burn mode, allowing reforming by means of the reforming reactor according to the invention using the hydrocarbons that are present in the exhaust gas.

Abstract: The invention concerns an exhaust gas cleaning system for an internal combustion engine with at least one catalytically active component which is configured such that its catalytically active coating comprises at least a first region with high light-off temperature and a high temperature resistance and at least a second region with a low light-off temperature and a reduced temperature resistance (relative to the first region). The exhaust-gas-side surface of the catalytically active coating in the intake region of the catalytically active component has at least a partial diffusion layer, or is at least partially covered by a diffusion layer.