PURPOSE: To control the rate of filtration, to prevent the clogging of a filter layer and to heighten the efficiency of filtration, by a mechanism wherein a receiving tank for receiving filtrate is mounted to a filter tank in a natural filtration system and liquid-head difference between the both or pressure diffrence applied to the filter layer is controlled.
CONSTITUTION: A liquid 2 to be filtered in an opening type filter tank 1 is filtered by means of a filter layer 3, and poured into an opening type receiving tank 4 and stored. A liquid-head of the tank 1 is detected by means of an air bubble tube 5 or a pressure detector 12 or the like, and input to a differential pressure transmitting instrument 7 for detecting the liquid-head and a differential pressure transmitting instrument 8 for detecting liquid-level difference with the receiving tank 4. The liquid-head detected by means of the differential pressure transmitting instrument 7 for detecting the liquid-level is input to a secondary regulator 10 through a primary regulator 9. A liquid-level of the receiving tank 4 is detected by means of the air bubble tube 5 or a pressure detector 13 or the like, and input to the differential pressure transmitting instrument 8 for detecting liquid-head difference, differential pressure with the tank 1 is input to the secondary regulator 10, and the opening of an automatic opening-and-closing valve is adjusted by operating signal from the secondary regulator 10 in an adjusting valve 11.
TAKEDA MASARU
HAYASHI HIROSHI
TAKAHASHI SADATOSHI
HARA NOBUO
| JP49083664B | ||||
| JPS4919290A | 1974-02-20 |