| 摘要 |
PROBLEM TO BE SOLVED: To remove the discharge of low concentration sulfuric acid to the outside and to provide an efficient exhaust gas desulfurization system. SOLUTION: The exhaust gas desulfurization system is provided with a desulfurization tower 4 which has a catalyst vessel 6 therein, supplies waste gas 100 from an inlet 5 on the side wall at a tower lower part, at the same time, supplies water from above the catalyst vessel 6 by means of a sprinkler nozzle 7 and subjects SOx in waste gas to desulfurization reaction up to dilute sulfuric acid (H2 SO4 ), an exhaust flue 13 which discharges the desulfurized and purified waste gas from an exhaust port 12 at a tower head part to the outside, a sulfuric acid concentration tank 50 which concentrates sulfuric acid via a discharging pump 10 from the desulfurization tower 4, a sulfuric acid concentration meter 62 which is made to branch from a discharge line 61 of sulfuric acid discharged from the desulfurization tower 4 and measures the concentration of sulfuric acid, and a controlling means 64 which performs change-over control of a switching valve 63 of sulfuric acid line according to the measurement of the concentration meter 62. |
