Process for removing nitric oxide, nitrous oxide and carbon monoxide from a gas stream

Abstract

The invention relates to a process for removing nitric oxides, nitrous oxide and carbon monoxide from a gas stream (1), comprising: (a) Removing nitric oxides from the gas stream (1) by adding an oxygen comprising gas (3) to the gas stream (1), oxidizing the nitrogen monoxide in the gas stream to form nitrogen dioxide, thereby obtaining a gas stream depleted in nitrogen monoxide and washing the gas stream depleted in nitrogen monoxide with water (7) to obtain a gas stream depleted in nitric oxides (11); (b) Oxidizing at least a part of the carbon monoxide in the gas stream depleted in nitric oxides (11) to form carbon dioxide, thereby obtaining a gas stream depleted in carbon monoxide (19); (c) Converting nitrous oxide in the gas stream depleted in carbon monoxide (19) into nitrogen and oxygen, if the gas stream depleted in carbon monoxide (19) is free of carbon monoxide, or, if the gas stream depleted in carbon monoxide (19) still contains carbon monoxide, into nitrogen and oxygen and/or carbon dioxide to obtain a purified off-gas stream (25).

Dependencies are inferred from the claim text.