MEMBRANE SEPARATION ACTIVATED SLUDGE TREATMENT APPARATUS, AND MEMBRANE SEPARATION ACTIVATED SLUDGE TREATMENT METHOD

摘要

PROBLEM TO BE SOLVED: To provide a membrane separation activated sludge treatment apparatus capable of markedly enhancing filtering efficiency, capable of suppressing the damage and contamination of a filter membrane and improved in waste water treatment efficiency.SOLUTION: A membrane separation activated sludge treatment apparatus 1 includes a biological treatment part 2 for mixing flocculated sludge formed by a biological flocculation means, and a purified treated water forming part 3 for obtaining purified treated water by membrane filtration. The biological treatment part 2 has a biological flocculation tank 24 for forming the flocculated sludge by the biological flocculation means, and a sludge-containing biologically treated water storage tank 21 for mixing the formed flocculated sludge and waste water to form mixed water and biologically treating the mixed water to obtain sludge-containing biologically treated water. The non-permeated water formed by a membrane unit 31 is more concentrated in the flocculated sludge as compared with the sludge-containing biologically treated water in the sludge-containing biologically treated water storage tank 21. A means for transferring the non-permeated water to the biological flocculation tank 24 is also provided.