| 摘要 |
PURPOSE:To suppress the accumulation of nitrite nitrogen and to efficiently remove org. matter by controlling the amounts of air, oxygen enriched air and oxygen blown into a fluidized bed type reactor using a bacteria immobilized carrier using the redox potential of the reactor and providing a post stage ozone contact tank. CONSTITUTION:A fine powder of shaft furnace water slag is used as a bacteria immobilizing carrier to improve the sedimentation properties of bacteria and the concn. of bacteria is kept high in a fluidized bed type reactor. Further, by setting the redox potential of the fluidized bed type reactor to a certain value range, the oxidative decomposition of BOD and TOC in waste water is promoted and the formation of nitrite nitrogen is suppressed. In such a case that the destruction and fragmenting of activated sludge are generated when a too much amount of air is used corresponding to the kind of the org. matter in a waste fluid or the BOD concn. in the waste fluid and redox potential is not kept, oxygen enriched air and/or oxygen is supplied to perform aeration. An ozone contact bed is arranged to the rear stage of the fluidized bed type reactor to oxidize remaining nitrite nitrogen to nitrate nitrogen. |
