“Welcome to Nakagawa, stay and live in Nakagawa” Nakagawa Town in Fukuoka Prefecture, blessed with greenery and water, will be home to a new water purification plant that adopts the latest technology.

Swing Corporation’s “Immersion Type PVDF” membrane technology allows monitoring of the membrane conditions by eyesight as they are not housed in casings, offering an advantage of improved maintenance control efficiency. The technology further incorporates various other ideas for reducing construction cost and lowering the life cycle cost.

A concern with a refurbishing project like this one, in which the existing water purification plant remains in operation during the work, is the heightened turbidity resulting from the reduced sedimentation capacity due to raw water quality changes. First updating the membranes of the current sand filtering facility into the immersion type PVDF membranes, with a superior tolerance for water quality changes, ensures a stable water supply even during the construction work. This allows the refurbishment work without suspending operation of the existing facilities.

The pressure for filtration is provided by water level difference. It does not require operation of auxiliary equipment such as water supply pumps, enabling filtration with no power.

PVDF membrane provides 20 times more physical strength per each hollow fiber than the existing membrane. It has a further advantage of higher tolerance for chemical washing and thus is easier to recover from clogging, allowing a longer membrane replacement cycle and contributing to lowering of life cycle cost.