METHOD OF CLEANING NITRIC ACID PRODUCTION EXHAUST GAS TO REMOVE NITROGEN OXIDES Russian patent published in 2004 - IPC

FIELD: gas treatment.

SUBSTANCE: method comprises mixing exhaust gas with methane and passing thus obtained gas mixture onto two catalyst beds wherein nitrogen oxides are reduced and simultaneously gas stream undergoes thermochemical heating preferably on at least one of the beds and is further used as working medium. According to invention, methane or gas mixture is preliminarily mixed with ammonia-containing gas or with ammonia serving as reducing gas whereas reduction of nitrogen oxides is performed preferably on the first-bed catalyst and thermochemical heating of gas stream is preferably performed on the second-bed catalyst involving oxidation of methane thereon. Invention allows capital outlays to be reduced by about 2.7 times, modernization time by 30 times, and ammonia consumption by 10-15%.

EFFECT: enhanced process efficiency.

3 cl, 1 tbl, 6 ex