| 摘要 |
<p>PURPOSE: To provide the biological membrane filter capable of maintaining the biological filtration function of the entire packed bed by removing only a large amt. of suspended matter depositing on the surface layer. CONSTITUTION: This downflow biological membrane filter has an inlet 1 for the water to be treated at the upper part and a treated water outlet 4 at the lower part and contains a packing material-packed bed 3. An inlet 23 for cleaning gas and/or liq. is provided in the upper part 3a of the packed bed at the position of 1/3 to 1/4 of the thickness of the bed from the lower part of the surface layer, and a waste cleaning water outlet 24 is furnished above the packed bed. When the filtration function is deteriorated, only the upper layer is cleaned by using a cleaning inlet set at the upper layer, and the function is restored.</p> |
