| 摘要 |
PURPOSE:To make stack gas contg. NOX harmless with high efficiency by vaporizing aq. ammonia in a vaporizer outside of a flue using a part of denitrated stack gas as vaporizing gas and returning the stack gas to the flue again. CONSTITUTION:A branch pipe 21 conducting denitrated exhaust gas to a vaporizer 20 with a recirculating fan 22 is disposed to a down stream of an exhaust gas flue 4 of a denitration apparatus 9. Ejection nozzles 25 for ejecting atomized ammonia or a precursor thereof, and a mixer 26 for mixing the atomized ammonia or the precursor uniformly with denitrated stack gas are housed in the vaporizer 20. Ammonia or the precursor is ejected through one or plural ejection nozzles matching a sectional area of a denitration catalyst bed 9 which is disposed to the flue 4 and to an upstream of the denitration catalyst bed 9 with the denitration stack gas which has been vaporized by the stack gas formed by being vaporized in the vaporizer 20 as ejection medium. As the result, stack gas contg. NOX is made harmless with high efficiency. |
