GRAVITY TYPE AUTOMATIC BACK WASHING TWO-STAGE SAND FILTRATION DEVICE WITH ELEVATED WATER STORAGE TANK

摘要

PROBLEM TO BE SOLVED: To provide a gravity type automatic back washing two-stage sand filtration device with an elevated water storage tank capable of attaining the efficiency of filtration treatment and the advancement of filtration performance without requiring the separate installation of the elevated water storage tank for supplying filtration-treated water into each breeding water tank.;SOLUTION: A gravity type automatic back washing two-stage sand filtration device with an elevated water storage tank includes: the elevated water storage tank 30 storing filtration-treated water; an upper filter section 10 having an upper filtration chamber 11 disposed via an upper filtration material 13 and an upper treated water tank 12; a lower filter section 20 having a lower filtration chamber 21 disposed via a lower filtration material 23 and a lower treated water tank 22; an upper connection pipe 15 connecting the upper treated water tank 12 to the elevated water storage tank 30; and a lower connection pipe 25 connecting the lower treated water tank 22 to the elevated water storage tank 30.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2018,JPO&INPIT