Daimler Chrysler Ag

Daimler-benz Ag

Brigitte Konrad

Bernd Krutzsch

Michel Weibel

Martin Hartweg

Walter Boegner

Andreas Hertzberg

Klaus Binder

Stefan Renfftlen

Herbert Guettler

Rolf Wunsch

Marko Weirich

Guenter Wenninger

Andrea Seibold

Leonhard Walz

Dirk Voigtlaender

Thomas Liebscher

Günter Wenninger

Dirk Voigtl&auml;nder

Holger Adler

Josef G&uuml;nther

Martina Heinau

G&uuml;nter Wenninger

Oliver Abet

Dirk Voigtländer

Heinz-Jost &Ouml;lschlegel

Josef Günther

Heinz-Jost Ölschlegel

An internal combustion engine includes an exhaust-gas aftertreatment device, and an operating method is for operating the internal combustion engine. The internal combustion engine is operable with a lean mixture and a rich mixture, the internal combustion engine having an exhaust-gas aftertreatment device, which includes a nitrogen oxide storage catalytic converter and a particle filter. When lean exhaust gas flows through the nitrogen oxide storage catalytic converter, it removes nitrogen oxides from the exhaust gas by storing them, and, when reducing exhaust gas flows through the nitrogen oxide storage catalytic converter, it produces ammonia through reduction of stored and/or supplied nitrogen oxides and releases it to the exhaust gas. Downstream from the nitrogen oxide storage catalytic converter, the exhaust-gas aftertreatment device includes a SCR catalytic converter, which reduces nitrogen oxides contained in the exhaust gas, using ammonia produced by the nitrogen oxide storage catalytic converter.

Exhaust-gas aftertreatment device with nitrogen oxide storage catalytic converter, and operating method therefor

An exhaust-gas cleaning system for cleaning exhaust gas from a combustion source so as to remove at least nitrogen oxides contained therein is provided. An ammonia-generation catalytic converter for generating ammonia uses constituents of at least some of the exhaust gas emitted from the combustion source during ammonia-generation operating phases. A downstream nitrogen oxide reduction catalytic converter is provided for reducing nitrogen oxides which are contained in the exhaust gas emitted from the combustion source using the ammonia generated as the reducing agent. According to the invention, a plasma generator for using plasma technology to generate reactive particles, which promote the ammonia-generation reaction, from constituents of the exhaust gas fed to the ammonia-generation catalytic converter during the ammonia-generation operating phases is connected upstream of the ammonia-generation catalytic converter. This ensures that sufficient ammonia is generated even at relatively low exhaust-gas temperatures.

Exhaust gas cleaning system having internal ammonia production for reducing nitrogen oxides

In a method for operating an internal combustion engine using exhaust gas purification system, and internal combustion engine, the method for operating an internal combustion engine with exhaust gas purification system, in which a rich mode of the internal combustion engine with a rich exhaust gas composition and a lean mode of the internal combustion engine with a lean exhaust gas composition are set alternately, and by the exhaust gas purification system with a rich exhaust gas composition ammonia is synthesized and stored and with a lean exhaust gas composition nitrogen oxides are reduced to form nitrogen by means of the stored ammonia. The quantity of fuel which is introduced by a combustion cycle of the internal combustion engine is introduced by at least one preinjection, at least one main injection and at least one afterinjection, the at least one preinjection and the at least one main injection are burnt under excess oxygen in order to generate a quantity of nitrogen oxides which is sufficient for the ammonia synthesis, and a rich or lean exhaust gas composition is set by the at least one afterinjection. The method may be used, for example, for exhaust gas purification in motor vehicle diesel engines.

Method for operating an internal combustion engine using exhaust gas purification system, and internal combustion engine

An exhaust-gas aftertreatment device with a nitrogen oxide storage catalytic converter for an internal combustion engine, and a method for operating an exhaust-gas aftertreatment device which is assigned to an internal combustion engine and has a nitrogen oxide storage catalytic converter. An SCR catalytic converter is arranged in the exhaust-gas aftertreatment device, it being possible for the exhaust gas which emerges from the nitrogen oxide storage catalytic converter to be fed to the SCR catalytic converter when the internal combustion engine is in a desulphating operating mode with a reducing exhaust-gas composition, in order for H S which is formed during the desulphating to be removed. When the internal combustion engine is in a desulphating operating mode, the following steps are performed: establishing a reducing exhaust gas composition upstream of the nitrogen oxide storage catalytic converter; releasing the sulphur which is bound in the nitrogen oxide storage catalytic converter, to form hydrogen sulphide (H S); feeding the hydrogen sulphide to an SCR catalytic converter which is arranged downstream of the nitrogen oxide storage catalytic converter in the exhaust-gas aftertreatment device; and reacting the hydrogen sulphide in the SCR catalytic converter to form sulphur dioxide under reducing exhaust-gas conditions. The method may be used in motor vehicles, e.g., passenger cars, with lean-burn internal combustion engines.

A method for producing a composite structure for microelectronic devices includes producing several microelectronic devices by means of a deposition method, preseeding a surface with growth seeds for a diamond and depositing the diamond layer from a gas phase. The diamond layer is provided with thin spots between the devices. According to the invention, the devices are laid down initially on a growth substrate directly and/or with the use of the material of the growth substrate. Following the deposition of the devices, the latter are seeded on their free surfaces for the diamond layer. The diamond layer is located on the seeded free surfaces of the devices.

Composite structure with a growth substrate having a diamond layer and a plurality of microelectronic components, and process for producing such a composite structure

A method of cleaning an exhaust gas from a combustion system that is operated alternately in lean and rich conditions includes intermediately storing nitrogen oxides during lean operation; releasing the stored nitrogen oxides, thereby producing ammonia and storing the ammonia during rich operation; releasing the ammonia, thereby reducing nitrogen oxides in a subsequent lean condition.

Process and apparatus for reducing nitrogen-oxide emissions in exhaust gas

A method for producing a composite structure for microelectronic devices includes producing several microelectronic devices by means of a deposition method, pre-seeding a surface with growth seeds for a diamond and depositing the diamond layer from a gas phase. The diamond layer is provided with thin spots between the devices. According to the invention, the devices are laid down initially on a growth substrate directly and/or with the use of the material of the growth substrate. Following the deposition of the devices, the latter are seeded on their free surfaces for the diamond layer. The diamond layer is located on the seeded free surfaces of the devices.

Composite structure with a growth substrate having a diamond layer and a

A material and a process for adsorbing and desorbing nitrogen oxides in exhaust gas systems of engines running on a lean mixture, which does not require a prior oxidation step, wherein a mixed oxide which has an oxygen-rich orthorhombic structure is used which changes to an oxygen-poor tetragonal structure as a function of temperature.

Process for absorbing and desorbing nitrogen oxides in exhaust gases

Growing community of inventors

Blaustein, Germany

Brigitte Konrad