Daimler-benz Ag

Daimler Chrysler Ag

Purem Abgassysteme Gmbh & Co. Kg

Daimler Ag

Günter Wenninger

Bernd Krutzsch

Friedrich Wirbeleit

Walter Boegner

Michel Weibel

Andreas Hertzberg

Klaus Binder

Christian Goerigk

Georg Huthwohl

Bernd Maurer

Stefan Renfftlen

Brigitte Konrad

Ekkehard Lindner

Rolf Wunsch

Marko Weirich

Stefan Kurze

Dirk Voigtländer

Michael Pabel

Ronny Meissner

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

A filter assembly for an exhaust gas purification system of an internal combustion engine. The filter assembly, has porous filter plate elements, connected with each other on their outer as well as on their inner peripheries, forming in pairs as filter pockets. Catalytic agents such as ammonia are applied to the filter pockets on the outer and/or inner sides to oxidize carbon black contained in the combustion gas. In particular, this filter assembly is compact and can be used for diesel engines of motor vehicles.

Filter assembly for an exhaust gas purification system

A process and apparatus for reducing the nitrogen oxide content in oxygen-containing emissions is provided, particularly for internal-combustion engines, particularly of diesel engines and directly injecting Otto engines for motor vehicles. The nitrogen oxides contained in the exhaust gas are reduced by a suitable reducing agent, such as hydrogen or hydrocarbons, on a DENOX catalyst. For achieving an improved conversion rate for the nitrogen oxides, a combination of hydrogen and hydrocarbons are used as reducing agents. In different operating ranges of the internal-combustion engine only hydrogen, only hydrocarbons, or hydrogen and hydrocarbons are added. Preferably, for this purpose, the quantity of supplied hydrogen or hydrocarbons is reduced or increased with an increasing engine load and/or catalyst temperature and/or rotational engine speed.

Process and apparatus for reducing nitrogen oxides in engine emissions

A diesel fuel containing an additive which improves the combustion of soot, for reducing the pollutant emission in the combustion exhaust gases from diesel engines by discontinuous burning-off of soot which has been precipitated in the exhaust gas filter, is described. For this purpose, a lithium, sodium or potassium salt of an aliphatic or aromatic alcohol, of a phenol, of an aliphatic acid or of a naphthoic acid, phenylacetic acid or cinnamic acid is added, singly or as a mixture, to the diesel fuel before the combustion of the latter in the internal combustion engine. As a result of the addition of the alkali metal salts, the ignition temperature of the soot precipitated in the particle filter is reduced, and the soot is oxidized at a temperature which is considerably lower than the normal ignition temperature. The regeneration range for the particle filter is therefore reached much more frequently in real running practice. This avoids a critical filter loading with soot, which can lead to filter damage during burning off. A further advantage of the process described is that, according to present knowledge, no additional substances with a health risk are emitted during running as a result of the addition of these alkali metal salts to the diesel fuel.

Diesel fuel containing an additive which improves the combustion of soot

Growing community of inventors

Stuttgart, Germany

Günter Wenninger