| 摘要 |
<p>PURPOSE:To keep the treatment load of raw supply water constant and to reduce load of after-treatment of sludge, by supplying, when part of sludge that has been separated from treated water from an aeration tank is restored to the aeration tank, at least part of the remaining sludge to an adjustment tank. CONSTITUTION:The raw supply water having different loads is supplied to the adjustment tank 2 through a raw water supply pipe 3. After the raw water is stirred by aeration to cause the loads to be uniform, it is treated in the aeration tank 6. Activated sludge of the treated water is separated by a separation tank 7 and is recovered into a distribution tank 8, part of the sludge is restored to the aeration tank 6, part of the remaining sludge is supplied to the adjustment tank 2, and the rest of the sludge is supplied to a sludge concentration reservoir 10. A sludge supply amount adjusting valve 14 is adjusted in accordance with variation of loads of the raw water, so that treatment loads of the raw supply water from the adjustment tank to the aeration tank 6 are made uniform.</p> |
