| 摘要 |
<p>PURPOSE:To prevent the dissolution rate of calcium compounds and a desulfurization ratio from lowering by increasing the dissolution rate of calcium compounds by controlling the variation range or frequency of pH of an absorbent liquid containing calcium compounds. CONSTITUTION:In the desulfurization of exhaust gas, the amount of absorbent slurry of calcium compounds to be fed is controlled by a controller so that the pH of the absorbent slurry is kept at a set value. The variation range or frequency of the pH is lowered l-10-hr, often 2-6hr, before an increase in the feed amount. An action is therefore taken to increase the dissolution rate of calcium compounds at that time. Practically, water containing less fluorine compounds and aluminum compounds is added into the absorbent liquid; at the same time, drainage is extracted corresponding the water added.</p> |
