| 摘要 |
<p>A denitrator which is equipped with: a noncatalytic denitration means in which a reducing agent is injected into an NOx-containing flue gas generated in a combustion furnace and the flue gas is noncatalytically denitrated; and a catalytic denitration means in which a reducing agent is injected into the noncatalytically denitrated flue gas and this flue gas is catalytically denitrated using a denitration catalyst. The denitrator is further equipped with: a control means that memorizes in advance a first correlation, which is a correlation between the load imposed on the combustion furnace and the amount of the reducing agent to be injected in the noncatalytic denitration means, and controls, on the basis of the first correlation, the amount of the reducing agent to be injected in the noncatalytic denitration means and that memorizes in advance a second correlation, which is a correlation between the load imposed on the combustion furnace and the inlet NOx concentration that is the NOx concentration measured on the denitration catalyst inlet side, predicts the inlet NOx concentration on the basis of the second correlation, and controls, on the basis of the inlet NOx concentration, the amount of the reducing agent to be injected in the catalytic denitration means; and a catalyst deterioration detection means that detects a deterioration of the denitration catalyst. When a deterioration of the denitration catalyst was detected by the catalyst deterioration detection means, the control means can replace the first correlation and the second correlation in accordance with the deterioration of the denitration catalyst.</p> |
