TREATMENT OF WASTE WATER IN WASTE REFUSE INCINERATION TREATMENT FACILITIES

PROBLEM TO BE SOLVED: To miniaturize treatment equipment by adding a chemical agent consisting of an alkali agent, a flocculant and a flocculation aid to inorg. waste water not only to insolubilize heavy metals as hydroxides but also to flocculate a suspended substance to sediment and separate them and mixing org. waste water with supernatant waste water to biologically treat org. matter. SOLUTION: Inorg. waste water stored in a first raw water tank 1 is sent to a reaction tank 2 and a chemical agent, a flocculant and a flocculation aid is added to inorg. waste water not only to insolubilize heavy metals as hydroxides but also to flocculate a suspended substance. Next, this inorg. waste water is sent to a sedimentation tank 3 and, after flocs are sedimented and separated, alkaline supernatant waste water is sent to a neutralization tank 4 and a neutralizing agent is added to the supernatant waste water to neutralize the same. Subsequently, the waste water is sent to a second raw water tank 5 to be stored therein and org. waste water is added to the waste water and this mixed waste water is sent to a biological treatment tank 6 and org. matter is metabolized and decomposed by aerobic bacteria bonded to a contact material. Thereafter, the waste water is sent to a sedimentation tank 7 and sludge composed of decomposed matter of org. matter is sedimented and separated to be sent to a treated water tank 8.