FILTER UNIT, CONTINUOUS FILTER USING SAME AND WASHING METHOD FOR FILTER ELEMENT OF FILTER UNIT AND CONTINUOUS OPERATION OF CONTINUOUS FILTER

摘要

PURPOSE: To realize continuous operation for filtration by arranging washing nozzles inside and outside a filter element that can be reciprocated in the axial direction to effectively wash and simultaneously arranging plural filter units side by side. ;CONSTITUTION: As filtration is continued, the differential pressure between the raw water side and water filtrate side rises by foreign matters deposited on the inner peripheral wall of a filter element 12. When that the differential pressure becomes the specified one or more is detected, a continuous filter 1 is shifted to the washing process. When a shaft 25 is turned to make branch pipes 29, 32 coincide with the axes of an outlet pipe 9 and an inlet pipe 8 respectively, the filter element 12 is interrupted from communication with a raw water chamber 2 by sealings 31, 34 to communicate with a washing water drain pipe 38. An inner washing nozzle 20 is installed so that the spray may obliquely strike on the inner peripheral wall to wash the foreign matter deposited on the inner wall so as to scrape it out. An outer washing nozzle 21 is installed just near the outer periphery of the filter element to wash out the foreign matter stuck on the inner peripheral wall in a backwash manner. The filter element is transferred in the axial direction to axially perform uniform washing.;COPYRIGHT: (C)1994,JPO&Japio