| 摘要 |
<P>PROBLEM TO BE SOLVED: To easily and precisely evaluate a deterioration degree of denitration catalyst during an actual machine operation. <P>SOLUTION: A denitration apparatus includes denitration catalyst for decomposing nitrogen oxides by the reaction between ammonia added into exhaust gas J flowing in a flue 1 with the nitrogen oxides in the exhaust gas. After the addition of the ammonia into the exhaust gas is suspended for a set time, the addition of the ammonia into the exhaust gas is started at an ammonia mole ratio set for the nitrogen oxide concentration of the exhaust gas flowing in the flue at an inlet side of the denitration apparatus. During a period after the addition of the ammonia into the exhaust gas is started until the nitrogen oxide concentration in the exhaust gas flowing at an outlet side of the denitration apparatus is stabilized, integration values obtained by multiplying the nitrogen oxide concentration flowing at the outlet side by a flow rate of the exhaust gas flowing in the denitration apparatus are obtained for the initial introduction point of time of the denitration catalyst and for each passage of time from the initial introduction point of time. By comparing the integration value at the initial point of time with the integration of value for each passage of time, the deterioration degree of the denitration catalyst is determined. <P>COPYRIGHT: (C)2013,JPO&INPIT |
