Patent ID: 8142655
Filing Date: 2012-03-27
Classification: B01D,C02F

Abstract:
1. A filtration unit that is immersible in raw water that is held inside a reservoir tank or a reservoir pond, and comprises a membrane module that filters the introduced water, comprising: a casing which is in the shape of a box having a bottom and includes the membrane module housed on a membrane module side of the casing and an activated carbon cartridge housed on an activated carbon cartridge side of the casing, the activated carbon cartridge having activated carbon provided in cartridge form therein; and a support for supporting the casing by suspending it in the raw water, wherein the casing is provided with an intake port extending through a vertical sidewall thereof to introduce the raw water into an interior of the casing, and a first opening/closing device that is installed on this intake port and controls a flow of the raw water into the interior of the casing, and the activated carbon cartridge side and the membrane module side are spatially separated within the casing so as to allow the raw water introduced into the interior of the casing to circulate from the activated carbon cartridge side to the membrane module side, and wherein the casing comprises a partitioning wall, positioned to separate the activated carbon cartridge from the membrane which are housed in the casing, and a connecting port disposed in the partitioning wall that connects the activated carbon cartridge to the membrane module and is adapted to allow the water which is introduced into the interior of the casing to circulate from the activated carbon cartridge side to the membrane module side, and wherein a second opening/closing device is provided in the connecting port and is adapted to prevent the raw water from counter-flowing from the separated membrane module side to the separated activated carbon cartridge side, and wherein the second opening/closing device includes a shut off valve, and is provided with a tube-shaped component which has a predetermined length and which connects the separated activated carbon cartridge side of the casing to the separated membrane module side of the casing, the second opening/closing device being capable of controlling the circulation of the raw water circulated from the separated activated carbon cartridge side of the casing to the separated membrane module side of the casing, and is adapted to be capable of closing the circulation of the raw water between the separated activated carbon cartridge side of the casing and the separated membrane module side of the casing by closing the shut off valve.