Abstract: A method of removing salt from seawater to produce potable freshwater. Apparatus that may be used with the method includes a large metal cylinder, with open top and bottom ends, anchored to the sea floor offshore. Several pressure hulls may be attached to the side of the cylinder. Within each pressure hull there are several reverse osmosis devices (“RODs”), each containing a membrane that will allow water molecules, but not sodium and chlorine ions, to pass through. Due to the pressure differential, freshwater passes through the membranes by reverse osmosis, and is pumped out of the pressure hulls to a storage facility onshore. After equilibrium is reached, the pumps for the brine can be turned off, as gravity will cause brine to flow down from the pressure hulls through an opening in the bottom of the cylinder. Alternatively, a reverse osmosis system may be supported on an elevated undersea platform.

Abstract: Methods and systems for monitoring and/or controlling membrane separation systems or processes are provided. The present invention utilizes measurable amounts of inert fluorescent tracers and tagged fluorescent agents added to a feed stream to evaluate and/or control one or more parameters specific to membrane separation such that performance thereof can be optimized. The methods and systems of the present invention can be utilized in a variety of different industrial applications including raw water processing and waste water processing.

Abstract: A method for separating at least one lower polarity fluid from a mixture of fluids having varying polarity, comprising contacting at least one low polarity or non-polar polymeric membrane with the mixture of fluids under conditions such that the at least one lower polarity fluid selectively permeates through the membrane, wherein the membrane is one which has a ratio of heteroatoms chemically bonded to the carbon atoms in the membrane to the number of carbon atoms of less than about 0.2, preferably less than about 0.05.

Abstract: Methods and systems for monitoring and/or controlling membrane separation systems or processes are provided. The present invention utilizes measurable amounts of inert fluorescent tracer(s) added to a feed stream to evaluate and/or control the purification of such feed stream during membrane separation. The methods and systems of the present invention can be utilized in a variety of different industrial applications including raw water processing and waste water processing.

Abstract: In the invention, the pipe lines around permselective membranes and the surfaces of permselective membranes are intermittently disinfected by adding an inexpensive acid such as sulfuric acid or the like to pre-treated crude water so as to make the water have a pH of 4 or lower. Accordingly, the invention provides a method of surely disinfecting the permselective membranes in membrane separation systems.

Abstract: The present invention is a water processing method comprising the steps of separating boron-containing water in a reverse osmosis membrane module to provide a permeated water and subjecting a part of the obtained permeated water to boron removal using an adsorbent, wherein the water subjected to the boron removal is mixed with the water not subjected to the boron removal of the permeated water to provide a mixed water. The present invention provides economic water processing method and apparatus that remove the boron from boron-containing water.

Abstract: A method of boron removal from saline water containing boron and magnesium or calcium salts including a multi-stage reverse-osmosis (RO) separation process and comprising the steps of a first stage RO separation at pH<8.2; a second stage RO separation over at least part of the first-stage permeate; a third stage RO separation over the second-stage brine. The method is characterized in that the second stage separation is carried at pH>9 and the brine concentration is limited to a degree preventing Mg(OH)2 or CaCO3 scaling on RO membrane surfaces, the permeate constitutes product water, and the brine contains boron and magnesium or calcium ions; the third stage separation is carried at weak-acid pH, whereby the bulk of the magnesium or calcium ions are separated with the brine, while the bulk of the boron ions are retained in the permeate.

Abstract: The invention pertains to a method and a device for desalting water by reverse osmosis, particularly for desalting seawater, in which saltwater (10) is introduced under a first pressure (p1) into a pressure-compensation device (2) and conducted from pressure-compensation device (2) at a second, higher pressure (P2) into a membrane module (3), wherein desalted water (12) and concentrated saltwater (13) are conducted out of membrane module (3), wherein the concentrated saltwater (13) conducted out of membrane module (3) is continuously introduced at roughly second pressure (P2) into pressure-compensation device (2) and used there to apply roughly second pressure (P2) to saltwater (10) introduced into pressure-compensation device (2) and to introduce saltwater (11) into membrane module (3), and wherein the introduction of concentrated saltwater (13) into pressure-compensation device (2) and the conduction of concentrated saltwater (14) out of pressure-compensation device (2) are accomplished by means of controll

Abstract: A water purification system and method based on reverse osmosis is provided. An inlet of supplied water to be purified is driven by a first flow propelling device which drives inlet supplied water flow to an upstream side of a membrane. An outlet of reject water from the upstream side of the membrane is driven by a second flow propelling device. The first and second flow propelling devices are powered by a common driving shaft or otherwise linked or controlled so that a ratio of inlet flow to outlet flow is maintained constant and a rate of permeate flow from a downstream side of the membrane is also kept constant.

Abstract: A method is described for processing fruit or vegetables, e.g., cranberries, into two different juices. One of the two juices has a relatively high level of acids. The other of the two juices has a relatively low level of acids. The method of the invention entails providing three juice streams. The first juice stream is passed through a nanofiltration apparatus or some other apparatus that is capable of preferentially removing acidic compounds from the raw fruit or vegetable juice feedstock. This process creates two juice fractions: a juice fraction that is relatively enriched in acids and a juice fraction that is relatively reduced in acids. The second juice stream is combined with the juice fraction that is relatively enriched in acids to create a juice that has a relatively high level of acids. The third juice stream is combined with the juice fraction that is relatively reduced in acids to create a juice that has a relatively low level of acids.

Abstract: A spiral wound membrane module comprises a spiral wound membrane element including a separation membrane having high back pressure strength. In filtration running, raw water introduced from a raw water inlet of a pressure vessel is subjected to dead end filtration, and permeate is taken out from a permeate outlet. In washing, wash water containing a chemical having a contaminant separating function is introduced from an end of a water collection pipe through the permeate outlet for performing back wash reverse filtration with a back pressure of 0.05 to 0.3 MPa. The filtration running is temporarily stopped for maintaining the pressure vessel in a state sealed with the raw water and the permeate for a prescribed time. Thus, contaminants adhering to the membrane surface of the spiral wound membrane element are separated. A treatment system is formed by connecting units comprising spiral wound membrane modules in parallel with each other.

Abstract: A method and system for providing Water for Injection using reverse osmosis. Water for Injection can be produced by reverse osmosis and the reverse osmosis membrane can be kept in a constantly self-sanitizing condition. One way of obtaining a constantly self-sanitizing condition is to maintain the reverse osmosis membrane at an elevated temperature during production of Water for Injection.

Abstract: The present invention relates to the recovery of heat energy, e.g., the heat of compression, from the production of pressurized gases, in particular nitrogen (N2), but also other gases such as compressed dry air. This invention is directed to a system and method for increasing the efficiency in use of energy by recovering energy normally wasted in one device and using the energy in another device needing the energy. In particular, this invention is directed to recovering the heat of compression from a gas generation plant to warm cooling water that is also used as feed water to an ultra pure water generation plant.

Abstract: A composite reverse osmosis membrane is described, which includes a polyamide skin layer on a porous support, with a contact angle between the polyamide skin layer surface and water of 45° or less. The composite reverse osmosis membrane has a high salt rejection and also a high water permeability. This composite reverse osmosis membrane is produced by forming a polyamide skin layer on a porous support having the steps of: forming a layer on the porous support by coating a solution A including one or more compounds having at least two reactive amino groups; contacting the layer with a solution B comprising one or more polyfunctional acid halide compounds; and subsequently, contacting the layer with a solution C comprising the polyfunctional acid halide compound of a higher concentration than the solution C. The concentration of the polyfunctional acid halide compound in the solution C is preferably at least 1.2 times of the solution B.

Abstract: The invention relates to a low-water-consumption method for processing an exposed color reversal photographic film. This method comprises the circulation of this exposed film in: i) a black and white development bath, ii) a first washing bath, iii) a reversal bath comprising at least a buffer agent liable to pass through a nanofiltration membrane and, in addition, the collection of waters leaving the said reversal bath, the circulation of these waters through a nanofiltration device to produce a permeate that is recycled in the said first washing bath, a water volume at least equivalent to that supplied by the said permeate being rejected via the overflow and the said buffer agent being chosen so as to keep the pH in the first washing bath between 5 and 7.

Abstract: Methods of treating a high salinity liquid, such as seawater, containing boron are provided, including adjusting the pH of the liquid to about 8 to about 9.5, optionally adding a scale inhibitor to the liquid, passing the liquid through a reverse osmosis device, and recovering a permeate having a boron concentration less than about 2 ppm. One embodiment includes removing colloidal matter from the liquid using a membrane filtration system, such as ultrafiltration or microfiltration, prior to passing the liquid through the reverse osmosis device, and preferably prior to adjusting the pH of the liquid.

Abstract: A method of desalination of sea water is disclosed and the method comprises the steps of drawing a stream of sea water into a supplying tank; passing a high pressure air via the top end of the supplying tank; delivering sea water to a pressure tank; and performing desalination via a plurality of reverse osmosis films.

Abstract: Wastewater, particularly black water and/or gray water, is used, for example in an aircraft, for processing fuels used in a high temperature fuel cell. For this purpose a liquid hydrocarbon fuel is used for producing an emulsion for use as fuel in the high temperature fuel cell. The liquid hydrocarbon fuel is preferably kerosene. The liquid hydrocarbon fuel is first emulsified with the wastewater which is first passed through a treatment such as filtering, reverse osmosis, or any other cleaning treatment that makes the wastewater suitable for the emulsifying the liquid hydrocarbon fuel. The emulsion is then supplied as fuel to the high temperature fuel cell. Thus, smaller and hence lighter storage facilities for the wastewater can be used.

Abstract: A multi-stage apparatus and a process for recycling used engine coolant employs a combination of filtration, dissolved air floatation, centrifugation (hydrocyclone separation), semi-permeable nano filtration, reverse osmosis, and continuous deionization for separating ethylene glycol, with or without propylene glycol, and water from used engine coolant. The engine coolant is pre-filtered through a series of filters. The filters remove particulate contaninates. This filtered fluid is then subjected to dissolved air floatation and/or centrifugation to remove organic petroleum contaminants. Then, it is pressurized prior to being passed through semi-permeable nano filtration. The nano filtration separates the feed stream into a ultra filtration solution and a concentrated waste solution. The concentrate solution is returned to a centrifuged coolant tank for continuous circulation through the nano filtration device.

Abstract: Sodium chloride and purified water are recovered by treating salt water that contains sodium chloride with an integrated reverse osmosis and electrodialysis system, which includes an efficiency-enhancing feature that is one or more of the following: the use of univalent anion and univalent cation selective membranes in the electrodialysis unit; the addition of a nanofiltration unit to process the diluate from the electrodialysis unit; or operation of the electrodialysis unit at an elevated pressure. Magnesium and bromine can optionally be produced when the salt water contains these materials.

Abstract: A method and apparatus for processing waste streams wherein a slipstream is formed on the upstream side of an ultrafiltration membrane (120) to carry collected and concentrated filter reject to a microfilter (170) via a slipstream through a conduit (155) at a very low flux through the microfilter. The low flux gives the particles in this stream a chance to interact and thus form an irregular matrix that itself helps to trap particles. The effluent from this matrix and microfilter is returned upstream of the ultrafiltration membrane via a conduit (165) to be repeatedly collected and concentrated. The suspended solids removed from the reject stream and microfilter may then be disposed of directly without further processing. For metal ions, the removal efficiency of ultrafiltration membrane can be improved by injecting sulfide compounds or other compounds upstream of ultrafiltration membrane.

Abstract: In a multistage osmosis treatment method including: subjecting liquid to reverse osmosis treatment in a first-stage reverse osmosis separation module (31); adding an alkali agent to the obtained permeated water (5) to adjust a pH value of the permeated water (5) in an alkaline region; and further subjecting the permeated water (5) to reverse osmosis treatment in second and subsequent stage reverse osmosis separation modules (32), the supply water (5) to the second-stage reverse osmosis separation module (32) is subjected to at least one treatment selected from deferrization, demanganization, decarboxylation, and addition of a chelator and a scale inhibitor. Because of this, multistage reverse osmosis treatment is provided, in which the separation performance of the second and subsequent stage reverse osmosis membrane modules is enhanced, and liquid can be separated and purified to a high degree, and boron and the like that are not dissociated in a neutral region can be separated at a high blocking ratio.

Abstract: A method and system (10) for utilizing water to transfer heat are provided. In one embodiment, the system (10) includes two water softeners (16) for removing the hardness of the feed water. The water softeners (16) are coupled to a filtration device (14) and deliver the softened water thereto. The filtration device (14) removes minerals from the water so as to produce a filtered water volume and a rejected water volume. The filtration device (14) delivers the filtered water volume to a heat exchanger (12). The heat exchanger (12) evaporates the filtered water volume and produces a mineral deposit volume. The mineral deposit volume is delivered to the filtration device (14) for removal of the mineral deposits so as to produce a recycled water volume and a blowdown water volume. Thereafter, the recycled water volume is delivered to the heat exchanger (12) for reuse, and the blowdown water volume is discharged to the waste vessel (24).

Abstract: A filtration module has at least one nanofiltration or reverse osmosis membrane. The module is used to filter water and, when optionally fitted with at least one membrane adapted to selectively reject hardness causing salts, is used to remove hardness. Methods of cleaning using acidic solutions or gaseous carbon dioxide are discussed. Cleaning methods include the steps of periodically stopping permeation, injecting an acidic solution or gaseous carbon dioxide into the feed/retentate side of the module, holding the acidic solution or gaseous carbon dioxide in the module for a selected time, and flushing the acidic solution or gaseous carbon dioxide from the feed/retentate side of the module after expiration of the selected time.

Abstract: This invention relates to a method and a device for purifying water by means of inverted osmosis, ultra or nanofiltration or the like. The device comprises a raw water inlet (10) which via a pressurizing pump (15) is connected to a filter housing (24) in order to achieve an increased pressure of the water in the filter housing. The filter housing comprises a filter inlet (23), an outlet conduit (27) for purified water and a reject outlet (29) which is connected to a first branched off conduit (20) connected to the filter inlet (23) in order to form a circulation circuit (19) for concentrated unpurified water. The circulation circuit comprises a circulation pump (21) and a second branched off conduit (31) connected to a sewage drain (32) or the like for tapping off unpurified water.

Abstract: Systems and methods by which to subject cellulosic fibers to alkaline treatment are provided. The systems and methods of the invention include equipment, such as nanofiltration units and slurry concentrators, which result in a lowered overall consumption of alkaline solution during alkaline treatment. The systems and methods of the invention further allow the components of hemicaustic streams produced by such alkaline treatments to be utilized in higher value end uses.

Abstract: A method for modifying the rejection characteristics of a reverse osmosis membrane having a separating surface. The method comprises performing oxidation (1) of the reverse osmosis membrane, whereby a decrease in the salt rejection of said reverse osmosis membrane takes place, in effect rendering the reverse osmosis membrane ultrafiltration or microfiltration characteristics.

Abstract: This invention refers to the use of surface-active agents as a treatment of effluents containing acetic derivatives by tangential filtration characterized from aqueous solutions containing between 20 and 35% in weight of acetic derivatives having been optionally decanted and filtered in a conventional manner in order to remove suspended impurities, which undergo the addition of one or more surface-active agents, while submitted to the tangential filtration process via polymer membranes, the cutting range of which may vary between 0.001 and 0.

Abstract: A method and well is disclosed for desalinating saline aquifer water, wherein saline aquifer water flows from a subsurface aquifer layer directly into a downhole aquifer inflow region of a desalinated water production well in which a downhole assembly of one or more desalination and/or purification membranes is arranged, which separate the saline aquifer water into a primary desalinated water stream which is produced through the well to surface and a secondary concentrated brine reject stream, which can be disposed into a subsurface brine disposal zone.

Abstract: A system and method of desalinating brackish water from an inland, underground water supply is disclosed. The system includes a source of underground water, at least one distillation and/or non-distillation desalination stage, and a source of waste heat from a power generator. The method includes desalinating brackish water drawn from an underground source using waste heat from a power generator and one or more non-distillation and/or distillation desalination stages. Potable water is recovered from both the brackish underground water using waste heat from the power generator, while dissolved salts are taken to dryness and removed as solids and from the flue gases.

Abstract: A method of treating a high salinity liquid, such as seawater, containing boron is provided. The method includes adjusting the pH of the liquid to about 8.5 to about 9.5, optionally adding a scale inhibitor to the liquid, passing the liquid through a reverse osmosis device, and recovering a permeate having a boron concentration less than about 1 ppm.

Abstract: Heat exchanger packs having a first set of passageways for receiving a stream of ambient air and a second set of passageways for receiving a stream of warm water laden air is disclosed. The first set of passageways and second set of passageways being separate and permitting the warm water laden air stream to be cooled by the stream of ambient air so that water can condense out of the warm water laden air stream. Cooling tower configurations including the heat exchanger pack are disclosed for achieving effluent plume abatement, and capture of a portion of the effluent for replacement back into the cooling tower reservoir or as a source of purified water.

Abstract: A method for treating livestock wastewater includes directing screened wastewater to a hydrocyclone/separation tank system. The hydrocyclone directs the wastewater stream in a generally helical fashion to create bubble-particle aggregates. Activating chemicals can be added to the wastewater upstream of the hydrocyclone or within the hydrocyclone itself. The wastewater is channeled from an outlet of the hydrocyclone through a diffuser to a separation tank, where the bubble-particle aggregates are separated as they rise and accumulate on a free liquid surface of the tank. The treated wastewater settles below the bubble-particle aggregate accumulation and is transferred to a reservoir for later use as irrigation water or barn wash water. Salts may also be removed from the wastewater by filtering the wastewater through salt-removing filters before the wastewater is transferred to the reservoir.

Abstract: A spiral reverse osmosis membrane element of the present invention includes a plurality of bag-shaped reverse osmosis membranes, permeated liquid passage members arranged inside the reverse osmosis membranes, and a plurality of feed liquid passage members interposed between the reverse osmosis membranes, those membranes and passage members being wound around an outer surface of a hollow pipe in a manner that only the interiors of the reverse osmosis membranes communicate with through-holes formed in the surface of the hollow pipe. Each of the feed liquid passage members is a mesh member having series of quadrilateral meshes formed by a plurality of linear members crossing each other. Two opposite cross-points out of four cross-points of each of the quadrilateral meshes are in line in parallel with an axial direction of the hollow pipe. And relations 2 mm≦X≦5 mm and X≦Y≦1.

Abstract: An apparatus and method of removing salt from seawater to produce potable freshwater. In the first preferred embodiment, a reverse osmosis system containing one or more reverse osmosis devices (“RODs”) is supported by a platform on the sea floor. In the second preferred embodiment, a cylinder is supported by a flotation device, and the reverse osmosis system is retained on the cylinder. In both the embodiments, an elongated brine return runs downhill on the sea floor. The RODs each contain a membrane that will allow water molecules, but not sodium and chlorine ions, to pass through. Due to the pressure differential, freshwater passes through the membranes by reverse osmosis, and is pumped out of the pressure hulls to a storage facility onshore.

Abstract: A system and method are provided which removes bromine biocide used in effluent process streams without the use of chemicals or complex mechanical systems. In particular, the system and method of the present invention remove bromine biocide by photodissociating the bromine, thereby forming innocuous salts. Ultraviolet energy may be used to provide the energy for photodissociation, in particular ultraviolet energy supplied by medium pressure Hg vapor lamps.

Abstract: A process and apparatus for membrane treatment of a feed liquid to form a product liquid includes feeding a feed liquid, typically an aqueous solution such as tap water, to a primary membrane. The primary membrane separates the feed liquid into a primary membrane retentate which is retained by the primary membrane, and a primary membrane permeate. The primary membrane retentate is then fed to one or more supplemental primary membranes, or to a secondary membrane. The primary membrane retentate (or supplemental primary membrane retentate if a supplemental primary membrane is employed) is separated by the secondary membrane into a secondary membrane retentate which is retained by the secondary membrane, and a secondary membrane permeate passes through the secondary membrane. The secondary membrane retentate may either be collected and disposed of, or may be fed to one or more supplemental secondary membranes.

Abstract: The present invention is directed to a method and apparatus for desalinating seawater utilizing a two stage seawater desalination system, a first stage including at least one high performance nanofiltration membrane to receive seawater feed pressurized by a first stage pump sufficiently and to produce a first permeate, and a second stage including at least one high performance nanofiltration membrane to receive the first permeate pressurized by a second stage pump to between about 200 psi and about 300 psi to produce potable water.

Abstract: A process for removing soluble and insoluble inorganic, organic, and microbiological contaminants from a fluid stream employing a pretreatment module, a post-treatment module, a recycle stream module or any combination thereof, and a membrane module, is provided. The process provided reduces the problems associated with membrane fouling and increases contaminant removal capacity.

Abstract: A separation end cap adapted for connecting adjacent separation elements is provided. The end cap may be located at the distal ends of a separation element and is adapted for connection with a permeate tube located within the separation element. In one embodiment the end cap includes an inner hub for receiving an O-ring to seal against an inner hub of an end cap on an adjacent separation element. The inner hub of the end cap may be spin-welded to the outer surface of the permeate tube. A locking structure on an outer hub of the end cap co-acts with a locking structure on an end cap of an adjacent separation element to releaseably lock the end caps and, therefore, adjacent separation elements. The locking structure preferably provides a predetermined axial force on the O-ring to seal the connection between permeate tubes of adjacent separation elements.

Abstract: A slurry recycling system for use in a chemical mechanical polishing (CMP) apparatus for polishing a workpiece by using a slurry containing an abrasive, a pH agent and a deionized water is provided. The slurry recycling system includes a slurry collection tank for storing the slurry used in the CMP apparatus as a recyclable slurry; an ultra filter for separating, from the recyclable slurry, a fluid ingredient containing the pH agent and the deionized water and the abrasive to allow the abrasive to be reintroduced into the slurry collection tank; and a reverse osmosis filter for separating, from the fluid ingredient, the pH agent and the deionized water to allow the pH agent to be reintroduced into the slurry collection tank and to allow the deionized water to be discharged out.

Abstract: A tidal-powered desalinization system is mounted on a barge that oscillates about fixed pier structures, generating a two-way pumping action. The two-way pumping action is changed to a single direction flow of seawater. The sea water is directed into an on-board desalinization system. Fresh water is produced and collected in reservoirs, without an intervening generation of electricity.

Abstract: The present invention is for method and means for purification of water using reversed osmosis. Water is forced through a membrane element (10) under pressure, which is obtained by a high pressure pump (2), where the water which is supplied to the element (10) is both from the outside supplied, unpurified water and internally circulated water that has passed by the element at its inlet side. The high pressure pump operates intermittently and the quantity of water that is circulated internally is at least as large as the quantity of water that is supplied from the outside. After that the pressure has been reduced there is a time delayed flush cleaning of the element (10) by flushing with water that is supplied from outside.

Abstract: Processes and apparatus are disclosed for producing clear reverse osmosis retentates having silica concentrations which are substantially supersaturated in silica from feedwaters having silica concentrations, without substantial formation of alkali-soluble scale having substantial silica content in the associated reverse osmosis apparatus, by adjusting the pH of such feedwaters to an acidic pH range prior to reverse osmosis in accordance with this invention. Also disclosed are related processes and apparatus for periodically removing minor amounts of alkali-soluble scale having substantial silica content from the apparatus.

Abstract: A multi-stage apparatus and a process for recycling used engine coolant employs a combination of filtration, dissolved air floatation, centrifugation (hydrocyclone separation), semi-permeable nano filtration, reverse osmosis, and continuous deionization for separating ethylene glycol, with or without propylene glycol, and water from used engine coolant. The engine coolant is pre-filtered through a series of filters. The filters remove particulate contaminates. This filtered fluid is then subjected to dissolved air floatation and/or centrifugation to remove organic petroleum contaminants. Then, it is pressurized prior to being passed through semi-permeable nano filtration. The nano filtration separates the feed stream into a ultra filtration solution and a concentrated waste solution. The concentrate solution is returned to a centrifuged coolant tank for continuous circulation through the nano filtration device.

Abstract: Upon recovering a fluorochemical surfactant from a fluorochemical-containing aqueous solution, there is provided a method for recovering the fluorochemical surfactant from the aqueous solution containing the surfactant. In the method, the fluorochemical surfactant is recovered by subjecting the aqueous solution containing the fluorochemical surfactant to a filtration treatment step with a reverse osmosis membrane so as to obtain from the aqueous solution, a concentrated aqueous solution in which the concentration of the fluorochemical surfactant is increased.

Abstract: The invention relates to a method for producing crystals from thermally sensitive solids. According to this method, the solid is dissolved in at least one solvent and the solution is concentrated by drawing off the solvent to beyond the saturation concentration of the solid, so that crystallized solids are formed. The solvent is caused to permeate a substantially semi-permeable membrane, preferably by being subjected to excess pressure. The inventive method can be carried out substantially isothermally in order to prevent the thermally sensitive crystals from being damaged.

Abstract: Water purifier using membranes, ion exchange resins and electricity to remove ionic, organic and suspended impurities from water to produce high quality, pure water. Supply water is pre-treated by directing it first into a sediment pre-filter module, a softener module and a sediment removal and dechlorination module. The pre-treated water is supplied to a reverse osmosis module which separates the water into two streams (a purified water stream and a concentrate stream) by collecting fluids from both sides of pressurized membranes. The purified water is passed to an electrodeionization module which further purifies the water and directs the water to an ultraviolet sterilization module. The concentrate stream is divided into a recycle stream which is passed to the inlet of the reverse osmosis module and a waste concentrate stream which flows to an outlet of the machine. A control method for the water purifier is also disclosed.

Abstract: An object of the present invention is to provide a water purification system capable of treating for-treatment water containing a nitrogen compound such as polluted ground water efficiently and achieving a reduction in size of the system. The water purification system comprises an electrodialyser for concentrating a nitrogen compound in polluted ground water as for-treatment water containing a nitrogen compound, a nitrogen treatment device for treating the nitrogen compound in the for-treatment water treated in the electrodialyser by electrolysis as an electrochemical process, the for-treatment water containing at least chloride ions, and a pump for returning the for-treatment water treated in the nitrogen treatment device to the electrodialyser.

Abstract: Reverse osmosis filtration is conducted using a rotatable inner body having an axis of rotation and a reverse osmosis filter member disposed on the inner body. An outer body is disposed about the inner body and spaced therefrom to provide an annulus between an annular outer surface of the filter member and an annular inner surface of the outer body to receive a liquid to be filtered. A source of the liquid under pressure is communicated to an inlet to the annulus. The inner body is rotated at a rotational speed effective to generate Taylor or other vortices in the liquid in the annulus.