| 摘要 |
PURPOSE:To provide a usage of denitration apparatus in which the temperatures for starting and stopping the denitration apparatus are made as low as possible without generating ammonium nitrate when NH3 is injected to exhaust gas containing NO2 for the catalytic reduction with a denitration catalyst. CONSTITUTION:In the catalytic reduction of NO2 and NO by the denitration catalyst in which exhaust gas 2 containing NO2 and NO is introduced to a denitration apparatus equipped with an NH3 injector 5 and a denitration catalyst 6 and injected with NH3, the percentage of NO2 to the nitrogen oxides in the exhaust gas is obtained, and an exhaust gas temperature which gives the theoretical rate of denitration obtained by the percentage is obtained from the temperature characteristic curve of the denitration catalyst to set up the exhaust gas temperatures for starting and stopping the NH3 injection based on the temperature obtained. In this way, the operation temperature of the denitration apparatus can be decreased without generating ammonium nitrate so that the total NOx discharged from HRSC, etc., can be decreased remarkably. |
