| 摘要 |
Provided is a method and device for biologically treating organic wastewater, wherein a fixed bed carrier is used in a first biological treatment tank (bacterial dispersion tank) so that a fixed bed can be formed without growing animalcules and thus the bacterial dispersion tank can be operated in a high load state with no fear of misoperation. Organic wastewater is supplied to a first biological treatment tank 10 and then biologically treated by bacteria therein to form a bacterial dispersion. Then, first biologically treated water containing the bacterial dispersion is passed from the first biological treatment tank 10 to a second biological treatment tank 20 and biologically treated therein. In the biological treatment tanks 10 and 20, a plurality of sheet-shaped carriers are disposed in such a manner that a face direction is arranged along the perpendicular direction. Thus, fixed beds 11 and 21 are formed and air is diffused from below the fixed bed 11 at a diffusion rate of 0.1-5 m3 air/m2 bottom area/min. |
