| 摘要 |
PURPOSE:To properly control the concn. of O2 incorporated in exhaust gas of the inlet of a nitration apparatus, by partially branching combustion air and mixing it into exhaust gas of the upstream side of the stack gas denitration apparatus which is provided to the downstream side of a furnace for burning fuel such as a boiler and a combustion furnace. CONSTITUTION:Exhaust gas after combustion is introduced into an air preheater 5 via a mixer 3 and a denitration apparatus 4 from a flue 2 and discharged after denitration and heat exchange. Then when the concn. of O2 incorporated in exhaust gas discharged from the mixer 3 is measured and the value is not more than preset value, a first damper 7 is opened and the prescribed amount of combustion air branched from an air line 6 is fed to the mixer 3 provided to the upstream side of the denitration apparatus 4 in order to introduce it into the denitration apparatus 4. Thereby the concn. of O2 incorporated in the denitration apparatus 4 is most favorably kept. While measuring the amount of combustion air to be fed into a furnace 1 with a flowmeter or the like so that it is not made insufficient by means of the branching of combustion air from the air line 6, the divergence of a second damper 8 is adjusted and the prescribed reaction is performed in the furnace 1. |
