| 摘要 |
PROBLEM TO BE SOLVED: To provide and develop an automatic back wash sand filtration device for elevated water supply, capable of automatically performing back wash sand filtration work and when filtering, supplying water to an elevated location from two places of a treatment water tank by using pump pressure.SOLUTION: An automatic back wash sand filtration device for elevated water supply is formed by integrally laminating a back wash water tank 2, a filtration chamber 3 and a treatment water tank 4. A back wash water pipe 5 which communicates the back wash water tank and the treatment water tank is provided therebetween, and a back wash electric valve A is provided in the back wash water pipe. When performing back washing, a raw sea water supply pipe 7 for supplying water to the filtration chamber in filtering is closed, the back wash electric valve is opened, and a back wash discharge pipe 8 is opened, before discharging waste water. When filtering, treated water produced by filtering raw sea water supplied from the raw sea water supply pipe is supplied from a treated water elevated pressure-supplying pipe 6 or 9 to an elevated water tank X. |
