CATALYTIC OXIDATION OF NOX/SOX IN FLUE GASES WITH ATMOSPHERIC OXYGEN AS THE OXIDATION REAGENT

摘要

The present application solves the existing problem of using very expensive oxidation reagents, such as H₂O₂ and ozone, in removal of NO_x and SO_x from the flue gases, by performing the NO_x and SO_x oxidation with atmospheric oxygen. The combined system for catalytic oxidation and wet-scrubbing of simultaneously both NO_x and SO_x from a flue gas and manufacturing fertilisers, comprises: (a) an air separation unit for separating atmospheric oxygen from air and thereby producing an air stream substantially enriched with atmospheric oxygen for oxidation of NO_x and SO_x, (b) an adsorption and oxidation reactor containing an oxidation catalyst and designed to receive said air stream and a flue gas stream containing NO_x and SO_x, to adsorb said streamed gases, and then to carry out the catalytic oxidation of said NO_x and SO_x by said oxygen to yield nitric and sulphuric acids, (c) a separator and reactor control unit for separation of products and liquids and controlling said catalytic oxidation and wet-scrubbing; and (d) a vessel containing gas or liquid ammonia, connected to said adsorption and oxidation reactor or to said separator and reactor control unit, and streaming said ammonia into the adsorption and oxidation reactor or into the separator and reactor control unit to react with the nitric and sulphuric acids and to yield ammonium nitrate and ammonium sulphate fertilisers.