Method for reducing nitrogen oxides in flue gas

US4950473A · kind A · utility

Assignees

• Didier Engineering GmbH · DE
• Didier-Werke AG · DE

Inventors

• Claus Flockenhaus · Essen, DE
• Manfred Galow · Essen, DE
• Klaus Merkel · Essen, DE
• Hans-Eugen Buhler · Königstein, DE
• Hartmut Kainer · Wiesbaden, DE

Key dates

• Filing date: Oct 27, 1988
• Grant date: Aug 21, 1990
• Expiry date: Oct 27, 2008

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F23J2215/10
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Apparatus and method for reducing nitrogen oxides in flue gas within a flue gas duct includes a number of distributor tubes for the injection of a reducing agent into the flue gas within the duct. Each distributor tube includes a control valve to be able to set an appropriate injection of the reducing agent to respond to different concentrations of the nitrogen oxides within the flue gas over the cross section of the flue gas duct. Each distributor tube comprises at least two parallel distributor tube segments which extend from opposite sides of the flue gas duct to the center of the flue gas duct. The two parallel distribution tube segments include a plurality of openings along the lengths thereof to supply the reducing agent generally evenly throughout their aligned portions of the cross section. The control valve is employed to adjust the reducing agent to provide the proper quantity thereof which corresponds to the particular concentration of nitrogen oxides within the flue gas at each corresponding portion of the entire cross section.