SEPTIC TANK

摘要

PROBLEM TO BE SOLVED: To perform large flow rate adjustment even by a small amount of air by ensuring sufficient air lift water depth while suppressing the suction of accumulated sludge. SOLUTION: A septic tank is equipped with a sedimentation treatment tank 1 and a treatment tank 2 receiving water to be treated from the sedimentation treatment tank 1 to treat the same and an air lift pump is provided to the sedimentation treatment tank 1 to adjust a flow rate. The air lift pump 3 is formed into a Ushape and the leading end on the suction side of the air lift pump 3 is provided above the intermediate position of the tank and the lower part of the U-shaped part 3b of the air lift pump 3 is positioned at the lower part of the tank.