| 摘要 |
PURPOSE:To lessen propagation of actinomycetes in a system and to suppress foamed scum by disposing a separating vessel for subjecting the underwater suspended matter in in-station return water to floating concentraction just before return of this return water into a grit basin, subjecting this water to scum sepn. by floating the actinomycetes with the fine air bubbles in the separating vessel and separating the underwater suspended matter in a filter bed. CONSTITUTION:The separating vessel 6 which is a device for separating and removing the actinomycetes scum is installed in a confluent area of the scum return water, the supernatant water of the sludge concentrated layer and the water desorbed from the dehydrated sludge. The confluent water is admitted into the grit basin through the separating vessel 6. The in-station return water is admitted through an inflow pipe 62 into the separating vessel 6 and air is aerated into the water through an air supply pipe 70, by which the air is excessively dissolved into the water. Next, the air dissolved in the water floats in the form of fine air bubbles and the underwater suspended such as actinomycetes in the water are pushed up onto the water surface by the buoyancy thereof to form suspended materials 6A when the pressure in the separating vessel 6 is reduced by opening a pressure reducing valve 61. Next, the actinomycetes gather on the filter bed and form suspended materials 6B when the treated water is passed through the filter bed by opening a treated water valve 65. |
