| 摘要 |
<p>PURPOSE:To eliminate the blowing of excess air while maintaining the specified volume of the liquid to be retained in an absorption column and oxidation column by blowing air of the quantity corresponding to the quantity of SO2 absorbed in the absorption column to the oxidation column and correcting the liquid depth control value of a pump tank by the apparent specific gravity determined from the air-liquid ratio of an aq. soln. and air. CONSTITUTION:The quantity of the SO2 absorbed in the absorption column 2 is calculated from the values of the quantity of the waste gas and concn. of SO2 measured by detectors 14, 15 and a meter 16 and the air of the quantity corresponding to the absorbed SO2 is blown into the oxidation column 6 by operating a regulator 17 of an air line 7. The air-liquid ratio of the aq. soln. changes according to the quantity of the air to be blown and the apparent specific gravity thereof changes in the oxidation column 6; therefore, the apparent specific gravities of the cases of various gas-liquid ratios are preliminarily stored in a microcomputer contained in the meter 16 and the set value of the liquid depth to be controlled by the pump tank 5 is corrected and changed by the apparent specific gravity value according to the gas-liquid ratio in that stage, by which the specific liquid amt. is maintained in the oxidation column.</p> |
