DEVICE FOR TREATING WASTE WATER

摘要

PURPOSE:To decrease the excess sludge to be discharged to the outside of a system, by disposing an ultraprecision filter device contg. a porous filter medium constituted of a hollow tube or fiber group that can capture particles of <=1mum particle size in the flow behind an aerobic biomembrane filter bed. CONSTITUTION:Raw water is treated primarily with a screen 38 and is removed of coarse matter, whereafter the water is transferred to a control tank 10. The water therein is aerated preliminarily with an air diffusion pipe 41 communicating with a blower 40 and is transferred into an immobilized biomembrane filter bed tank 30 of submerged type where the water is subjected to a secondary treatment. The waste water in the tank 30 is kept fluidized by an air diffusion pipe 48 communicating with a blower 47 and is brought into contact with the membranes fixed with living things on a honeycomb body 46, whereby the waste water is purified. The entire volume of the water treated and purified in the filter bed 30 is subjected to a tertiary treatment of solid-liquid sepn. in an ultraprecision filter device 32, and is then disinfected by a disinfecting device 24 so as to be reused as industrial water. The device 32 is backwashed with water periodically to prevent clogging.