Regeneration eines NOx-Speicherkatalysators eines Verbrennungsmotors

摘要

The invention relates to an exhaust-gas cleaning device of an internal combustion engine with more than one cylinder, comprising an NOx storage catalytic converter positioned downstream from the internal combustion engine. The exhaust gas continuously flows into the NOx storage element of the catalytic converter in such a way that the NOx is absorbed in the NOx storage element as soon as the machine is run on a lean mixture and that NOx is released as soon as the oxygen concentration of the exhaust gas decreases, such that during the NOx release phase the engine is run at a gross lambda value which is slightly higher than the stoichiometric ratio of lambda = 1. To generate the near-stiochiometric exhaust gas flow with a gross value of lambda >/=1 some of the engine cylinders selectively and individually receive an enriched mixture while the remaining cylinders continue to be run on a lean mixture.