SEWAGE TREATMENT EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To directly and continually withdraw treated water containing no sludge component of the upper part of a separation membrane from a single tank so as not to obstruct a circulating water flow by diffusing air to wash the separation membrane by arranging an immersion membrane separator to the aerobic zone in the circulating water channel comprising the single tank and connecting a treated water withdrawing pipe to this apparatus. SOLUTION: A partition wall 12 is arranged in a single sewage treatment tank 1 to form a circulating water channel 2 and an aerobic zone 10 and an anaerobic zone 11 are demarcated in the circulating water channel 2. A stirring aerator 3 is arranged at the start position in the aerobic zone 10 and an immersion membrane separator 4 is arranged on the downstream side of the aerator. A raw water inflow port 13 is provided at the start position of the anaerobic zone 11. The air diffusion pipe 42 connected to the bottom part of the separation membrane 41 of the immersion membrane separator 4 and the treated water withdrawing pipe 43 connected to a pump 5 is connected to the upper part of the separation membrane 4. By this constitution, air is diffused to strongly wash the separation membrane 41 and treated water containing no sludge component is directly, continually and stably withdrawn from the withdrawing pipe 53.