METHOD FOR PRESSURE-DEHYDRATING FERMENTABLE ORGANIC LIQUID WITH HIGH EFFICIENCY

PURPOSE:To easily perform dehydrating work and to miniaturize a sludge treating installation by floating and separating sludge floc through gas generated in the case of heating fermentable organic liquid and dehydrating the floc at high pressure by a belt press type dehydrator. CONSTITUTION:Sewage discharged from the kitchen of a home and a flush toilet is sent to an initial sedimentation basin 12 through a grit chamber 10. Initially settled sludge obtained therein is sent to a concentration tank 13 together with excess sludge returned from the final sedimentation basin 15. Sludge is concentrated herein and thereafter sent to a separation tank 16 and separated into sludge floc which is concentrated and floated and separated water containing clean water of the lower part. Sludge floc is sent to a belt press type hydrator 17 and dehydrated. The belt press type hydrator 17 is formed by using a filter medium belt having large filtration capacity such as synthetic monofilament, a stainless wire gauze or a perforated rubber belt and so constituted that high pressure dehydration is enabled. Sewage in the sedimentation basin 12 is sent to the final sedimentation basin 15 through an aeration tank 14 and purified.