| 摘要 |
<p>PROBLEM TO BE SOLVED: To save magnesium hydroxide by constantly adjusting the injection amount of magnesium hydroxide appropriately by providing the instrument with a pH adjusting meter which inputs an output signal from a SiO2 adjusting meter and a pH concentration signal from a circulating liquid pH meter and controls the operation of a magnesium hydroxide injection valve. SOLUTION: A flue gas desulfurizer has a desulfurization-absorption tower 1 equipped with a demister 2, a circulating liquid spray nozzle 5, and an oxidizing air aeration nozzle 6, and a circulating pump 4 and a pH meter 7 are installed in a circulating line 4a which connects the nozzles 5 with the lower part of the tower 1. An oxidizing blower 3 is connected with the aeration nozzle 6. The output signal of a SiO2 adjusting meter 10 connected with a SiO2 adjusting meter 9 which is installed in an exhaust gas suction port 12 and the output signal of the pH meter 7 are input into a pH adjusting meter 11. The operation of a magnesium hydroxide injection valve 8 is controlled on the basis of both input signals so that the amount of magnesium hydroxide which is injected into the lower part of the tower 1 is adjusted appropriately.</p> |
