摘要 |
PROBLEM TO BE SOLVED: To provide a biological treatment tank and a method for operating the biological treatment tank, in which a carrier can be fluidized at an early stage when a carrier is thrown therein before the operation thereof is started and a startup time can be made shorter, and to provide a method for treating organic waste water.SOLUTION: In such a case that organic waste water is treated biologically in the biological treatment tank, when the carrier is thrown in the biological treatment tank, air is diffused from only a half side of air diffusion pipes to form a circulation flow in the biological treatment tank. Later, air is diffused from all of the air diffusion pipes. The biological treatment tank has a tower body and the height of the tower body is 6-11 m and a ratio of the height of the tower body to the diameter thereof is 1.5-5.0.SELECTED DRAWING: Figure 1 |