METHOD OF GASSES PURIFICATION FROM OXIDES OF NITROGEN Russian patent published in 1996 - IPC

FIELD: production of weak nitric acid, acids denitration and oxides of nitrogen removal from waste gasses. SUBSTANCE: subjected to purification gas is alternatively passing in direct and opposite directions through layer of catalyst divided at least for two parts. Between parts of catalyst layer ammonia is introduced in stoichiometric ratio to minimum concentration of oxides of nitrogen in gas. As concentration of oxides of nitrogen achieves given value, ammonia is introduced within 1 - 60 minutes in stoichiometric ratio to maximum concentration of oxides of nitrogen. EFFECT: improved quality of purification. 1 tbl