APPARATUS AND METHOD FOR TREATING SEWAGE

摘要

PROBLEM TO BE SOLVED: To provide a sewage treatment apparatus and waste water treatment method wherein a problem accompanied with solid-liq. separation in a final sedimentation basin is solved and a conventional filter device is improved and executed in use and stable and good quality of treated water is obtd. SOLUTION: In an apparatus for treating sewage by an activated sludge method wherein a hollow filter body 5 with an inlet part consisting of a water- permeable supporting material at least as a part of the surrounding wall and an outlet part as an opening and wherein filtration is performed by forming a filter membrane consisting of activated sludge and turbid substances on this supporting material is submerged and arranged in a biological reaction tank 2 and treated water is drawn from the filter body 5 through the outlet by water head difference between it and the succeeding tank, mesh opening of the supporting material is made as a separation particle diameter of at least 30μm and a thickness of at most 2mm.