PURIFYING DEVICE OF BATHTUB

摘要

PURPOSE:To prevent the lowering of filtering capacity at the time of injection. CONSTITUTION:A jet pump 5 and an intermittent valve 16 are arranged to a jet passage 4 and both ends of a circulating passage 6 are connected to the jet passage 4. A physical filter tank 7 and a biological filter tank 8 are arranged on the way of the circulating passage 6 in series and a circulating pump 10 is provided on this side of the inlet 9 of the physical filter tank 7 of the circulating passage 6. One end of a first bypass passage 11 is connected to the jet passage 4 between the suction port 2 of the jet passage 4 and the jet pump 5 and the other end of the first bypass passage 11 is connected to the part between the inlet 9 of the physical filter tank 7 of the circulating passage 6 and the circulating pump 10 through a first three-way valve 12 and one end of a second bypass passage 13 is connected to the circulating passage 6 in the vicinity of the outlet 14 of the physical filter tank 7. The other end of the second bypass passage 13 is connected to the first bypass passage 11 through a second three-way valve 15. A first opening and closing valve 17 is provided between the physical filter tank 7 and the biological filter tank 8.