APPARATUS AND METHOD FOR ANAEROBIC DIGESTION OF SLUDGE

摘要

PROBLEM TO BE SOLVED: To provide an apparatus and a method wherein in anaerobic digestion of sludge, supernatant liquor with good quality of water can be stably extracted without being affected by degree of digestion. SOLUTION: A hollow filter body 25 wherein at least a part of the surrounding wall is constituted with a water-permeable supporting material with a mesh opening of a separation particle diameter of at least 50μm and a thickness of at most 2mm is submerged below a scum layer 24 in an anaerobic sludge digestion tank 20 and a filter membrane consisting of digested sludge and turbid substances is formed on the supporting material and supernatant liquor is made to flow into the filter body 25 through the filter membrane by water head difference between it and the succeeding tank and the supernatant liquor is extracted from the filter body 25.