| 摘要 |
PURPOSE:To prevent a screen from cogging and lowering treating capacity by carrying out biological reaction treatment of organic drain pretreated with a super fine mesh screen and then ultrafiltrating it. CONSTITUTION:Raw liquid in a receiving tank 4 passes through a rough mesh screen 10 and a fine mesh screen 12 to be stored in a storage tank 8. Then, the same is sent to an activated sludge treatment tank 16 consisting of a foregoing stage treatment tank 18 and a following stage treatment tank 20 through a liquid charging pump 14 and activated sludge treatment is carried out gradually. A seventh chamber of the activated sludge treatment tank 16 is connected with an ultrafiltration device 42 through a pipe 39 and a circulation pump 40 and liquid to be treated is flowed by cross flow system to be separated into filtered liquid and concentrated liquid. After passing through an activated carbon tank 44, if required, filtered liquid is discharged as treated water. By said process, clogging of super fine mesh screen with biological membrane and lowering of treating capacity are prevented. |
