WASTE GAS CLEANING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a waste gas cleaning method wherein nitrogen oxide in a waste gas is removed and an unreacted matter in ammonia injected as a reducing agent for the nitrogen oxide is not emitted out of a system. SOLUTION: In a method of removing nitrogen oxide by bringing the nitrogen oxide in waste gas and ammonia injected as a reducing agent for the nitrogen oxide into contact with a catalyst, nitrogen oxide is removed by contact reduction in a waste gas front flow part and then oxidation of ammonia and removal of nitrogen oxide are simultaneously performed or removal of nitrogen oxide is performed after ammonia is oxidized and decomposed.