| 摘要 |
PROBLEM TO BE SOLVED: To prevent clogging of an ammonia injection pipe due to sticking of dust, and to stably inject ammonia into exhaust gas for a long period by providing a dust removing means for blowing air or steam toward an ammonia injection nozzle. SOLUTION: An air or steam piping 4 as the dust removing means blowing the air or steam toward the ammonia injection nozzle (b) is provided in an inlet duct of a denitrification device as a waste gas flue. When the ammonia 3 from the ammonia injection pipe 2 is injected into the flue from the nozzle (b), it comes into contact with NOx in the waste gas to reduce the NOx to N2 and remove it. A portion of the ammonia reacts with SOx in the waste gas at that time, and becomes acidic ammonium sulfate and it sticks to the vicinity of the nozzle 6 and deposits. Air or steam is ejected from the ejection nozzle 7 of the air or steam piping 4 and the acidic ammonium sulfate and the dust are scattered. |
