Process for catalytically reducing nitrogen oxides in combustion exhaust gases

US5370850A · kind A · utility

Assignee

• Metallgesellschaft AG · DE

Inventors

• Bernd Thone · Friedberg, DE
• Gerhard Schmidt · Mühldorf a. Inn, DE

Key dates

• Filing date: Oct 12, 1993
• Grant date: Dec 6, 1994
• Expiry date: Oct 12, 2013

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J27/053
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A combustion exhaust gas which is to be dedusted and denitrated is mixed with NH.sub.3 and at temperatures in the range of about 250.degree. to 600.degree. C. is passed through a fluidized bed. The fluidized bed contains a denitrating catalyst, which contains FeSO.sub.4. The combustion exhaust gas serves as a fluidizing gas in the fluidized bed. Fresh denitrating catalyst is supplied to the fluidized beg and comprises at least 90% by weight FeSO.sub.4, which contains water of crystallization and has particle size in the range from 1 to 150 micrometers. The treated exhaust gas is dedusted in an electrostatic precipitator.