Device and method for eliminating NOx and N2O

US9238196B2 · kind B2 · utility

Assignee

• THYSSENKRUPP INDUSTRIAL SOLUTIONS AG · DE

Inventors

• Meinhard Schwefer · Meschede, DE
• Rolf Siefert · Rheda-Wiedenbrück, DE
• Stefan Pinnow · Elsdorf, DE

Key dates

• Filing date: Dec 8, 2012
• Grant date: Jan 19, 2016
• Expiry date: Dec 8, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02C20/10
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Disclosed herein is a device and method for lowering the content of NOX and N2O in gases. The device comprises a container having therein two reaction steps connected in series. The first step removes NOX (DeNOX stage) by reducing NOX with a nitrogen-containing reducing agent. Downstream thereof, the second step removes N2O by catalytic decomposition of N2O to N2 and O2 (DeN2O stage). Each step comprises one or more catalyst beds through which flows gas to be purified. The catalyst bed of the DeNOX stage containing zeolites doped with transition metals, including lanthanides. The at least one catalyst bed of the DeN2O-stage contains one or more catalytically active compounds of elements selected from groups 5 to 11 of the Periodic Table, but not iron-doped zeolites. A device for introducing a nitrogen-containing reducing agent into the stream of the NOX and N2O-containing gas is further disposed upstream of the DeNOX stage.