METHOD FOR DISCHARGING SLUDGE FROM STORAGE TANK IN SLUDGE TREATING DEVICE BY ACTIVATED SLUDGE AND STRUCTURE THEREFOR

摘要

PROBLEM TO BE SOLVED: To maintain a sludge to be reutilized in an aerobic state and to enhance the dehydration efficiency of the sludge by storing a concd. sludge obtained by concentrating the treated sludge from an aeration tank in a concentration tank in a storage tank and returning the environmental sludge formed by supplying air to the stored sludge from the storage tank. SOLUTION: A circulating passage 14 is connected between a forced-feed pump 11 of a discharge passage 10 to a mixing tank 7 and a discharge cock 12 through a circulating cock 15. The circulating passage 14 is connected to a storage tank 6 and an air suction part 16 is furnished to the circulating passage 14. When a stored sludge is sent to the mixing tank 7 from the storage tank 6, the discharge cock 12 is opened and the circulating cock 15 closed. Meanwhile, when the stored sludge is not sent to the mixing tank 7 from the storage tank 6, the discharge cock 12 is closed and the circulating cock 15 opened. Accordingly, the stored sludge is sent to the circulating passage 14 by the pump 11 and then returned to the storage tank 6 as the circulating sludge. At this time, the stored sludge is passed through the air suction part 15, air is joined to the sludge current, and the air bubble is mixed in the sludge.