| 摘要 |
PURPOSE:To enhance the power of dehydrating treatment without the necessity of a sludge-thickening step, by adding a ferric flocculant to treated water from the step of biological treatment, separating the treated water under an acidic condition, and subjecting the separated water to advanced treatment while dehydrating the separated sludge. CONSTITUTION:After organic waste water 1 such as night soil is treated in the step 2 of biological treatment, the biologically treated water 3 (or a mixed slurry of it with excess biological sludge) is mixed with a ferric flocculant 4, e.g. ferric chloride or poly (ferric sulfate), and optionally an alkali agent 5, e.g. slaked lime, and separated into clean separated water 7 and conc. sludge 8 by using the step 6 of capillary suction-dehydration with felt, sponge or the like. The separated water is subjected to advanced treatment, while the conc. sludge 8 is supplied to a filter press 9 provided with a pressing mechanism to obtain dehydrated cake 10 having a low water-content and a dehydration filtrate 11. |
