Daimler Chrysler Ag

Mercedes-benz Aktiengesellschaft

Josef Gunther

Bernd Krutzsch

Roland Kemmler

Dirk Voigtlaender

Christof Schoen

Marko Weirich

Herbert Klein

Uwe Kleinecke

Wolfgang Oehler

Miechel Weibel

An exhaust-gas cleaning system removes at least nitrogen oxides contained in exhaust-gas from a combustion source. An ammonia-generation catalytic converter generates ammonia using constituents of at least some of the exhaust gas emitted from the combustion source during ammonia-generation operating phases. Downstream a nitrogen oxide reduction catalytic converter reduces nitrogen oxides which are contained in the exhaust gas emitted from the combustion source using the ammonia generated as reducing agent. A nitrogen monoxide generation unit is situated outside the combustion source, for enriching the exhaust gas which is fed to the ammonia-generation catalytic converter with generated nitrogen monoxide during the ammonia-generation operating phases. The system is used for cleaning exhaust gases of motor vehicle internal-combustion engines which are operated predominantly in lean-burn mode, removing nitrogen oxides which are contained therein.

Exhaust-gas cleaning system and method with internal ammonia generation, for the reduction of nitrogen oxides

In an internal combustion engine with at least two groups of cylinders of which each has an exhaust pipe with a catalytic converter and of which one group can be shut down so that it is inoperative during part-load engine operation, the exhaust pipes are joined downstream of the catalytic converters by a common pipe section, and vacuum generating means are provided for subjecting the exhaust pipe of the inoperative cylinder group upstream of its catalytic converter during part load operation when the one cylinder group is shut down to vacuum for pulling exhaust gas from the common pipe section into the catalytic converter of the inoperative cylinder group.

Piston-type internal combustion engine having two groups of cylinders

Growing community of inventors

Affalterbach, Germany

Josef Gunther