| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a biological treatment apparatus and a biological treatment method which enable reduction in agitation costs. <P>SOLUTION: The biological treatment apparatus comprises a biological treatment tank for biologically treating organic waste water, a pressure device for pressurizing sludge-containing liquid pulled out from the biological treatment tank, a membrane separator which performs the membrane filtration of the sludge-containing liquid pressurized by the pressure device to separate the liquid into treated water which is permeate passing through a separation membrane and sludge concentrate which is nonpermeate, and a return passage for returning the nonpermeate separated by the membrane separator into the biological treatment tank. The return passage is formed so as to supply the nonpermeate to the biological treatment tank from the bottom while maintaining the nonpermeate under a pressurized condition. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
