| 摘要 |
<p>PURPOSE:To reduce the consumption of NH3 by obtaining the provisional amt. of NH3 to be injected from the amt. of combustion gas, the concn. of generated NOx, and the concn. of NOx after denitration, obtaining further the amt. to be injected by the concn. of the residual NH3, and controlling by a temp. selector. CONSTITUTION:The amt. of combustion gas is calculated by an arithmetic unit 13 of the amt. of combustion gas, and the amt. of NOx is calculated along with the signal from an NOx analyzer 10b. The signal 15 of the set NOx concn., the signal of the denitration rate by a denitration rate arithmetic unit 19, and the signal of an arithmetic unit 18 of the amt. of excess NOx are inputted to an arithmetic unit 21 of the amt. of injected NH3 to obtain a provisional amt. (I) of injected NH3. A provisional amt. (II) of injected NH3 is obtained at an arithmetic unit 28 of the amt. of injected NH3 from the signal of an arithmetic unit 22 of the amt. of residual NH3 and the signal of a storage device 25 of the amt. of injected NH3. The smaller value between the provisional amts. of injected NH3 (I) and (II) is selected by a low selector 29, inputted to a temp. selector 26, then inputted directly to a NH3 flow rate regulator 30 when the denitration temp. is appropriate, and NH3 is injected from a nozzle 6.</p> |
