| 摘要 |
<p>PROBLEM TO BE SOLVED: To discharge highly concentrated excess sludge generated by drainage treatment in drainage treatment using a membrane separation purification tank. SOLUTION: Activated sludge and a membrane separator 32 are received in a membrane separation tank 12, drainage in the tank is purified by the biodegradation effect of the activated sludge and separated into solid and liquid by the membrane separator 32, and the treated water is taken out. The membrane separation tank 12 is divided by partitions 14, 20 into the first chamber 16 on the upstream side, the second chamber 18 on the downstream side, and a sludge storage tank vessel 22. In an ordinary treatment mode, drainage in the first chamber 16 containing activated sludge is transferred to the second chamber 18 through an opening 52, and drainage in the second chamber 18 containing activated sludge is returned to the first chamber 16 through a return conduit 38 to make the sludge concentration uniform. In a sludge concentration mode, the return of liquid is stopped, and sludge is concentrated in the second chamber and discharged into the storage tank 22.</p> |
