The hollow fiber membrane module contains a hollow fiber membrane bundle having bundled hollow fiber membranes, a housing with an internal space formed in which the hollow fiber membrane bundle is housed and a gas supply portion which disperses cleaning gas for the hollow fiber membrane in the internal space. The internal space has an upper space in which an upper-side part of the hollow fiber membrane is positioned and a lower space in which a lower-side part of the hollow fiber membrane is positioned. The gas supply portion is provided with pipe vent holes which disperse gas in the housing at a position in the upper space and diffusing vent holes which disperse gas in the housing at a position below the lower space.

A system and method for predictive analysis of Seawater Reverse Osmosis (SWRO) desalination plants receives first data associated with a SWRO plant, including a first set of parameters associated with seawater, a second set of parameters associated with a permeate, and a third set of parameters associated with a brine. The system determines a fourth set of parameters by applying normalization techniques to the received first data. The system determines, based upon the fourth set of parameters, a set of membrane performance parameters associated with the SWRO plant, or a set of diagnostic indicators associated with at least one of the SWRO plant and the seawater. The system outputs the determined set of membrane performance parameters or the set of diagnostic indicators.

A control method for a water purifier includes establishing a first cleaning passage which communicates a scale inhibiting mechanism with an RO membrane element of the water purifier and through which the scale inhibiting mechanism cleans the RO membrane element for a first preset time. The method additionally includes establishing a draining passage which is connected to the scale inhibiting mechanism and through which liquid in the scale inhibiting mechanism is drained out, and establishing a second cleaning passage which is in communication with raw water and through which the RO membrane element is cleaned with the raw water for a second preset time.

A control method and system for controlling the operation of a seawater injection system comprising at least one water treatment line in which seawater is forced through one or more coarse filtration unit(s), ultrafiltration unit(s) and at least one of a reverse osmosis unit and/or a nanofiltration unit to a water injection pump, and wherein the flowrate required to create differential pressure across membrane(s) of the ultrafiltration unit(s) is obtained by a boosting pump. A controller C implemented operation control is applied to adjust automatically the outlet pressure and flow of the boosting pump such that an average flowrate through the ultrafiltration units is maintained and determined as boosting pump flow divided by the number of active ultrafiltration units. A proportional-integral-derivative control mechanism is preferably applied to all adjustable flow/pressure regulating units in the seawater injection system.

A system for cleaning a membrane of the present invention includes: a first membrane filtration tank which includes a membrane and an aerator, filters inflow raw water by membrane filtration, and discharges treated water and water to be treated, respectively; a pressure gauge for measuring a transmembrane pressure and a flow meter for measuring a permeation flux which are provided at a treated water discharge line of the first membrane filtration tank; and a controller which calculates a water permeability recovery rate by calculating the water permeability from the differential pressure measured at the pressure gauge and the permeation flux measured at the flow meter, predicts a membrane contamination degree from the calculated water permeability recovery rate, and controls a back-pulsing interval and an intermittent aeration interval.

Disclosed are system and method for filtration capable of minimizing the damage of a filtration membrane module, reducing the energy consumption, and improving the filtration efficiency. The filtration method of the invention comprises performing a preliminary filtration of a feed water with first and second submerged-type filtration membrane modules; pressurizing an initial filtrate produced through the preliminary filtration with a pressure higher than an osmotic pressure of the feed water; filtering the pressurized initial filtrate with a reverse osmosis membrane module; interrupting the first submerged-type filtration membrane module performing the preliminary filtration; and backwashing the first submerged-type filtration membrane module caused to stop performing the preliminary filtration, wherein the preliminary filtration with the second submerged-type filtration membrane module is continuously performed while the first submerged-type filtration membrane module is backwashed.

There is provided a system for the removal of scaling precipitants obtained due to dewatering a solution including i. at least one membrane, such as FO membrane adapted to be at least partially surrounded by a feed solution and to receive a flow through of a draw solution; and ii. a device adapted to control the flow of said draw solution through said at least one membrane; wherein said system is configured to operate in at least three predetermined different modes of operation including; filtration mode, osmotic relaxation mode and pulsation mode, according to some demonstrative embodiments.

A method of operating a filtration apparatus according to the present invention is a method of operating a filtration apparatus which includes one or more filtration modules provided with a plurality of hollow-fiber membranes arranged in parallel in one direction and a pair of holding members configured to fix both ends of the plurality of hollow-fiber membranes, and one or more cleaning modules configured to supply bubbles from below the filtration modules, the method including an operation step of carrying out a filtration treatment with the filtration modules, and a cleaning step of cleaning the filtration modules while stopping the filtration treatment with the filtration modules for 0.25 to 3 hours. The cleaning step is performed at intervals of 12 to 72 hours.

A water treatment device (1) includes a primary unit (U1) having a plurality of primary elements (E1) as reverse osmosis membrane devices disposed in parallel to each other to separate water to be treated (SW) into primary condensed water (CW1) and fresh water (FW1); a pump (P) which feeds the water to be treated (SW) to the primary unit (U1); a secondary unit (U2) having secondary elements (E2) as reverse osmosis membrane devices, the secondary elements (E2) being provided in smaller number than the primary elements (E1) and disposed in parallel to each other to separate the primary condensed water (W1) into secondary condensed water (CW2) and fresh water (FW2); and a switching unit (2) provided only in the secondary unit (U2) among the primary unit (U1) and the secondary unit (U2) to separate at least one of the plurality of secondary elements (E2) so that treatment is disabled.

A resistivity adjustment device includes: a hollow fiber membrane module that is divided by a hollow fiber membrane into a liquid phase side area; a liquid supply pipe that communicates with the liquid phase side area; a liquid discharge pipe that communicates with the liquid phase side area; a gas supply pipe that communicates with the gas phase side area; a gas discharge pipe that communicates with the gas phase side area; a bypass pipe that communicates with the liquid supply pipe and the liquid discharge pipe to bypass the hollow fiber membrane module; and a first on-off valve that is connected to the gas discharge pipe and opens or closes a first passage inside the gas discharge pipe, wherein the first on-off valve opens the first passage to discharge water accumulated in the gas phase side area.