| 摘要 |
<p>PURPOSE:To enable the utilization of the sludge produced in a treatment for waste water from wet type desulfurization of waste gas as a secondary raw material and to treat the sludge efficiently without adverse influence on the desulfurization of the waste gas by mixing said sludge with a concd. gypsum slurry of a gypsum recovery stage and recovering the slurry. CONSTITUTION:Sludge slurries from the 1st and the 2nd settling tanks, F, H in a treatment stage for waste water are supplied into a mixing tank a, where the slurries are mixed with the concd. gypsum slurry discharged from a desulfurizer for waste gas. The slurry mixture is fed through a line 2 to a solid-liquid separating tank B, where separated cake 5 is recovered and is utilized effectively as gypsum for cement. Filtrate 3 and overflow water 4 are recovered in a recovery pit C, and recovered water 6 is fed to a raw liquid tank D in the treatment stage for waste water. Air 17 is blown to the liquid in a raw liquid tank D to treat the easily treatable COD. Heavy metals and fluorine are deposited in a flocculating reaction tank E and after an assistant 19 for condensation is added to the liquid, the liquid is fed into the tank F where the concentration and sepn. of the sludge are accomplished. The concd. slurry 11 of sludge is fed to the tank A. The supernatant liquid 10 is treated in a softening tank G and the sludge 14 produced by the treatment is fed to the tank A.</p> |
