Daimler Chrysler Ag

Daimlerchrylser Ag

Christof Sch&ouml;n

Bernd Krutzsch

Walter Boegner

Michel Weibel

Andreas Hertzberg

Dirk Voigtl&auml;nder

Josef G&uuml;nther

G&uuml;nter Wenninger

Stefan Renfftlen

Ralph Stetter

Norbert Ruzicka

Hans-Peter Holzt

Kirsten Hardenberg

Doris Schr&ouml;der

G&uuml;nter Karl

Renate Marx

Dirk Voightl&auml;nder

A method for the desulfurization of a nitrogen oxide adsorber of an exhaust gas purification device for a combustion system employs desulfurization phases that are intermittently implemented by a desulfurization control unit. During each desulfurization phase, the carbon monoxide concentration and/or the lambda value of the exhaust gas stream exiting the nitrogen oxide adsorber is recorded. A localized maximum that appears in the recorded course of the carbon monoxide concentration over time, or a downward slope that appears in the established course of the lambda value over time, falling from a temporary plateau value, is employed as criterion for terminating the desulfurization phase. The method may be used, for example, in exhaust gas purification devices in primarily lean-burning vehicle combustion engines.

Method and apparatus for desulfurizing a nitrogen oxide adsorber

A method for operating an exhaust-gas cleaning system having an NO adsorption accumulator and an SO trap, includes, in normal operating phases, feeding the exhaust gas to be cleaned first via the SO trap and then via the NO adsorption accumulator. The normal operating phases are from time to time interrupted by desulphurization phases for desulphurizing the SO trap. Means are provided for controlling the direction of flow of the exhaust stream so that it optionally passes firstly via the SO trap and then via the NO adsorption accumulator, or firstly via the NO adsorption accumulator and then via the SO trap, so that during the desulphurization phases the exhaust gas can be passed firstly via the NO adsorption accumulator and then via the SO trap.

Exhaust-gas cleaning system with nitrogen oxide accumulator catalyst and sulphur oxide trap and operating method therefor

A method and apparatus for periodically desulphating a nitrogen oxide or sulphur oxide storage vessel of an exhaust emission control system of a multi-cylinder internal combustion engine, in which an engine exhaust emission containing reducing agent and oxygen is fed to the nitrogen oxide or sulphur oxide storage vessel by setting a rich fuel/air ratio for a first subset of the engine cylinders and a fuel/air ratio which is, in comparison, leaner for the other cylinders. The distance between the fuel/air ratio for the first subset of the engine cylinders and that for the second subset of the engine cylinders is set higher in an initial storage vessel heating-up phase than in the subsequent desulphation mode, and/or control errors of the entire fuel/air ratio are eliminated by a predefinable set point value by modifying the fuel/air ratio either of just the first subset or just the second subset of the engine cylinders. Used, for example, in motor vehicles.

Method and device for periodically desulphating a nitrogen oxide or sulphur oxide storage vessel with rich/lean engine cylinder distribution

Growing community of inventors

Remshalden, Germany

Christof Schön

Growing community of inventors

Remshalden, Germany

Christof Sch&ouml;n

Christof Schön