Method for operating an exhaust aftertreatment system and exhaust aftertreatment system

US8468806B2 · kind B2 · utility

Assignee

• VOLVO LASTVAGNAR AB · SE

Inventors

• Lennart Andersson · Båstad, SE
• Jonas Edvardsson · Timrå, SE
• Jonas Jansson · Handen, SE
• Carl-Johan Karlsson · Handen, SE
• Lucas Megas · Handen, SE
• Anders Tuomivaara · Handen, SE

Key dates

• Filing date: Feb 21, 2008
• Grant date: Jun 25, 2013
• Expiry date: Apr 10, 2029

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A system and a method are provided for operating an exhaust aftertreatment system of an engine in which one or more constituents of the exhaust gas are oxidized in an oxidation catalyst and one or more constituents of the exhaust gas are deoxidized by means of a group of possible chemical reactions of different type between the one or more constituents of the exhaust gas and catalytic material arranged in a selective-catalytic-reduction catalyst, wherein the exhaust gas flows from the oxidation catalyst to the selective-catalytic-reduction catalyst, wherein the steps are performed: (a) adjusting at least one desired ratio among one or more pairs of the one or more constituents by varying a space velocity of the exhaust gas in at least the oxidation catalyst; (b) varying the space velocity of the exhaust gas by varying one or more operation parameters of the engine; and (c) establishing the ratio to a value at least approaching the desired ratio among the one or more pairs of the one or more constituents at the inlet of the selective-catalytic-reduction catalyst.