METHOD FOR REMOVING NITROGEN OXIDE

摘要

PURPOSE:To ensure that NOx is removed without the necessity to install a large-capacity ammonia injection equipment and release ammonia or unreacted NOx to an area outside the system by allowing a desorption gas to circulate in a circulation system path including an absorbent and a reactor in the desorption process and adjusting an ammonia supply in accordance with variations of a nitrogen oxide concentration. CONSTITUTION:A desorption gas desorbed from adsorption materials 4a, 4b which absorb a nitrogen oxide, is circulated in a circulation system path including an absorption material 4b and a reactor 10 in the desorption process. Then a fixed amount of ammonia is supplied to the circulation system path until the variation of nitrogen oxide concentration is reduced from the start of desorption process. After that, if the variation is insignificant, an ammonia supply is adjusted in accordance with a change in the flow of the nitrogen oxide on the inlet side of the reactor 10.