Abstract: A method for increasing the exhaust gas temperature of internal combustion engines, particularly for driving a motor vehicle under load in order to reach the necessary regeneration temperature of at least one component of an exhaust gas post-treatment system, has the step of placing the engine under load by at least one of the brakes of the motor vehicle and/or by the starting element of the motor vehicle.

Abstract: A method for increasing the exhaust gas temperature of internal combustion engines, particularly for driving a motor vehicle under load in order to reach the necessary regeneration temperature of at least one component of an exhaust gas post-treatment system, comprises the step of placing the engine under load by at least one of the brakes of the motor vehicle and/or by the starting element of the motor vehicle.

Abstract: An uncontrolled heat pipe (20) is used in a valve seat device (19) for transferring the waste heat from the exhaust gas acting on the metering valve (15) to a condensation zone (21) which is situated in an environment which is at a lower temperature, whereby the metering valve is cooled sufficiently to prevent a chemical change of a reducing agent which otherwise can be caused by high temperatures.

Abstract: To ensure the maximum possible conversion of nitrogen oxides in a DeNOx catalytic converter in an off-gas cleaning installation for reducing nitrogen oxides and, at the same time, to prevent the reducing agent which is used for the reduction from escaping into the environment, there is provision for the density of a reducing agent solution to be used to determine the volume of the reducing agent solution which is to be metered. The density is regulated in two ways, in that the temperature of the reducing agent solution is measured using a temperature sensor and set by a temperature-control device.

Abstract: When determining the amount of a reducing agent solution to be introduced into the exhaust gas of a combustion system, in particular of a diesel engine, for catalytically reducing the nitrogen oxides by the SCR process, the concentration of the reducing agent in the reducing agent solution as well as the parameters characterizing the operating state of the combustion system, the exhaust gas and/or the catalyst are taken into consideration. As a result, the safety margin with respect to a theoretically optimum amount to be introduced that is required to avoid a leakage of reducing agent can be reduced, whereby the conversion rate of the nitrogen oxides is improved.

Abstract: A tank for a vehicle having a selective catalytic reduction exhaust gas purification system operating with a reducing agent includes a fuel space for the vehicle fuel and a reducing agent space for the reducing agent. The fuel space and the reducing agent space are combined into a single structural that can be fastened as a whole to the vehicle by brackets on the structural unit. This utilizes the limited space available in any vehicle as efficiently as possible and eliminates the need to provide mounting arrangements for separate fuel and reducing agent tanks.

Abstract: Excessive NOx emission in a diesel internal combustion engine with SCR exhaust gas treatment is detected by a control unit. The excessive NOx emission value is determined from the catalytic-converter efficiency calculated for the metering of the reducing agent. In response, measures are taken, such as delayed start of the fuel injection, deactivation of a coasting cutoff, reducing an exhaust gas recirculation rate and/or increasing the idling speed. As a result, the NOx content in the untreated exhaust gas drops, the catalytic-converter temperature increases more quickly after a cold start, and the NOx emission is reduced.

Abstract: A NO.sub.x reduction system includes an SCR catalytic converter and a metering assembly for reducing agent. A control unit for the reduction system is integrated together with the actuators and sensors as a functional unit at the reducing agent container. This provides savings in terms of lines and plug-in connections, and relieves the burden on the control unit of the internal combustion engine.