TW200600462A - Drainage method of sewage treatment tank - Google Patents

Abstract

A drainage method of sewage treatment tank comprising setting a floating body and a drain pipe in a tank, wherein the floating body floats on the water surface of the tank, and the drain pipe has a water intake setting on the floating body at one edge of the drain pipe and a water outlet in another edge extending outwardly to the tank. There is water in the drain pipe. The water intake of the drain pipe and the water surface under the floating body form an isolated space, followed by decreasing the pressure of the isolated space to make the water surface raise. Further, water can enter the drain pipe through the water intake, and be discharged from the tank through the water outlet. For above, the water discharged by the drain pipe always is the water near the surface. When the aeration procedure is performed, the produced air can enter the isolated space to decline the water surface and avoid the sewage entry into the drain pipe.