| 摘要 |
<p>The process for the purification of wastewater by biological treatment that eliminates sludge such as carbon, nitrogen or phosphorus in the wastewater, comprises fixing a portion of microorganisms having different metabolic spectra on movable solid supports (2) to constitute a fixed fluidized biomass, treating the activated sludge by keeping other portion of microorganisms free, subjecting the treated sludge to a solid/liquid separation by flotation at a speed of greater than 10 m/H, and re-circulating a portion of the recovered sludge towards the activated sludge treatment. The process for the purification of wastewater for eliminating sludge such as carbon, nitrogen or phosphorus by biological treatment, comprises fixing a portion of microorganisms having different metabolic spectra on movable solid supports (2) to constitute a fixed fluidized biomass, treating the activated sludge by keeping other portion of microorganisms free, subjecting the treated sludge to a solid/liquid separation by flotation at a speed of greater than 10 m/H, and re-circulating a portion of the recovered sludge towards the activated sludge treatment. Concentration of suspended matter of the sludge subjected to the liquid/solid separation is 0.3-1.5 g/l. Conditions of heavy mass of free microorganisms culture is coupled with a treatment of nitrogen in conditions of low mass of microorganisms using the fixed fluidized biomass. The heavy mass of free microorganisms is provided with a first anoxic treatment area for eliminating a major portion of the carbon and a portion of nitrogen by heterotrophic bacterial action, and with a second aerated treatment area for eliminating nitrogen. The two treatment areas are physically separated, and a fraction of nitrate produced in the second aerated treatment area is re-circulated towards the first anoxic treatment area. An independent claim is included for an installation for the purification of wastewater.</p> |
