Internal-combustion engine system having a nitrogen oxide storage catalyst and an operating process therefor

US6161377A · kind A · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Walter Boegner · Waiblingen, DE
• Guenter Karl · Eßlingen, DE
• Bernd Krutzsch · Köngen, DE
• Christof Schoen · Winnenden, DE
• Dirk Voigtlaender · Ditzingen, DE
• Guenter Wenninger · Stuttgart, DE

Key dates

• Filing date: Oct 26, 1998
• Grant date: Dec 19, 2000
• Expiry date: Oct 26, 2018

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2200/0802
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

An internal-combustion engine system includes an internal-combustion engine with a pertaining engine exhaust gas system, an emissions control device having an NO.sub.x storage catalyst arranged in the exhaust gas system, a lambda probe for detecting the engine air ratio and devices for the periodic desulfurization of the catalyst at a raised temperature and a rich air ratio of the latter, as well as to an operating process suitable for this system. The desulfurization devices comprise secondary air feeding devices for feeding secondary air into the NO.sub.x storage catalyst. During the desulfurization phases, the engine is operated at a rich air ratio and secondary air is metered into the catalyst.