MOVING BED TYPE SAND FILTER, MOVING BED TYPE BIOLOGICAL MEMBRANE SAND FILTERING METHOD AND SYSTEM THEREFOR

摘要

PPROBLEM TO BE SOLVED: To provide a non-wasteful and stable moving bed type biological membrane sand filtering method. PSOLUTION: A moving bed type sand filter 1 is constituted so as to circulate filter media by utilizing an air lift 4 to wash them. The lost head of a filter bed 3, concretely, pressure P on a discharge side, a pressure difference between the upper and lower parts of the filter bed or the fluctuation of a water level is detected by using the moving bed type sand filter 1 to adjust the supply amount F of air to the air lift 4. An ascending flow moving bed type sand filter 1 is preferably used. The waste of energy required in operation can be omitted and the life of an apparatus, or the like, can be extended. This filter can be put to practical use in a moving bad type biological membrane sand filter. PCOPYRIGHT: (C)2003,JPO