| 摘要 |
<p>PURPOSE:To keep an aerobic atomospheric state, by providing a filter bed packed with a bacteria depositing particulate medium to the middle region in a biological membrane filter tank and providing an air vent pipe to the lower part of the filter bed. CONSTITUTION:A biological membrane filter tank 1 is constituted by forming a filter bed 3 by packing the space above a support bed 2 comprising large particles with a bacteria depositing particulate medium such as sand or anthracite. Above the filter tank, a backwashing water storage tank 4 is formed as the tank part integrally connected to the filter tank 1 and partitioned by a partition wall 5 and the air diffusion pipe 9 connected to an air supply pipe 8 is provided below the filter bed 3 and air for biological oxidation rises while being uniformely distributed to the entire surface of the filter bed 3 from said air diffusion pipe 9. Above the filter bed, air vent pipe 10 opened at the upper end thereof is vertically provided from the upper partition partition wall 5 of the filter tank 1. The air vent pipe 10 is also used as a raw water inflow passage and raw water is flowed so as to be countercurrently contacted with air discharged through said vent pipe 10 and the raw sewage flowed in the space above the filter bed 3 is purified through the filter bed 3.</p> |
