| 摘要 |
PURPOSE:To simplify and rationalize the treatment for org. waste liquid, by treating the org. waste liquid biologically then subjecting the biologically treated water to an evaporation treatment in an evaporation stage of an indirect heating type by a steam compression method and/or a multi-effect method. CONSTITUTION:Night soil 1 is admitted without dilution into a biological nitrification and dentrification stage 2 of a nitrifying liquid circulation system, whereby BOD, nitrogen, etc. are removed. Part 3 of the outflow slurry from the stage 2 is subjected to solid-liquid sepn. in a solid-liquid sepn. stage 4 such as a centrifugal concentrator. The concd. sludge is returned to the stage 2. On the other hand, there maining part 3' of the outflow slurry is mixed with separated liquid 5' and is admitted into an evaporation drying vessel 6 of a hermetic indirect heating type. The temp. of the inflow slurry 7 is increased to about 40 deg.C by the oxidation heat of microbes in the stage 2 and further the slurry is preheated to about 80 deg.C in a heat exchanger 9 by the condensed water 8 of steam. |
