| 摘要 |
<p>PURPOSE:To simplify considerably the titled treatment by subjecting activated sludge to a solid-liquid sepn. after biological treatment of org. waste water, aerating the separated water with gas contg. O2, evaporating and condensing the steam, and using the condensed water as the highly treated water of the above- described org. waste water. CONSTITUTION:Org. waste water 1 is biologically treated in a biological treatment stage 2, and the activated sludge slurry 3 flowing out of said stage is subjected to a solid-liquid sepn. in a solid-liquid sepn. stage 4 using a centrifugal concentrator or the like. The separated excess activated sludge 8 is fed to a sludge dehydration stage 7, where the sludge is separated to separated water 8 by the dehydration and dehydrated cake 9. The water 8 and the separated water 10 in the stage 4 are fed to an aeration tank 11 where the water is aerated by the gas contg. O2. Outflow water 12 is preheated with a heat exchanger 13 and is then fed to an evaporator 14'. Evaporated steam 15 is compressed and heated by a steam compressor 16, and is utilized as a heat source in the indirect heating section 17 of the evaporator 14' and a heat exchanger 13, by which the steam is made into highly treated water 19.</p> |
