WASTEWATER TREATMENT DEVICE AND METHOD

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive wastewater treatment device of a wet type flue gas desulfurization system, which prevents re-release of mercury contained in an exhaust gas in desulfurization thereof and performs the treatment for reducing the mercury concentration in a gypsum generated when desulfurizing in an absorption tower, and to provide a wastewater treatment method using the device.SOLUTION: A wastewater treatment device of a flue gas desulfurization system is provided with: a sulfur oxide-absorbing part 6 which introduces an exhaust gas including sulfur oxide from a combustion apparatus with a boiler and has a spray nozzle for spraying a lime stone-containing absorbent liquid; an absorbent liquid-storing part 11 provided below the absorbing part; a filter part 68 having a smaller hole size than the grain size of a mercury absorbent at a position dividing the inside of the liquid-storing part 11 vertically in two; a mercury absorbent-supplying part 60 provided above the level of the absorbent liquid in the liquid-storing part 11 on the upper portion of the filter part 68; and a first absorbent liquid extraction part for extracting the absorbent liquid in the liquid-storing part 11 to the lower part of the filter part 68 to supply the liquid to an absorbent liquid circulation path.