Abstract: A polymeric membrane includes an active layer on a support. The active layer includes at least two chemically distinct crosslinked, polyamide films, and the films are crosslinked with each other at an interface.

Abstract: An induced symbiotic osmosis pump (ISOP) (and method of using same) comprising: a closed loop comprising a riser pipe and a downpipe having substantially the same length fluidly communicating at a base with an induced osmosis semipermeable membrane and fluidly communicating at an opposed end with a brine pump fluidly communicating with a pressure exchanger fluidly communicating with a reverse osmosis membrane, the downpipe comprising a check valve; the induced osmosis semipermeable membrane of the closed loop fluidly communicating with an initial reverse osmosis module fluidly communicating with a brine pump fluidly communicating with a source of fluid having an initial salinity; the brine pump electronically communicating with an electrical source; and, the reverse osmosis membrane fluidly communicating with a storage tank.

Abstract: The present invention includes systems and methods for treatment of seawater RO system for recovering most of the water (i.e., 85-90%) from the concentrate of a brackish groundwater reverse osmosis treatment system that may use, e.g., a batch method. With proper pH control and antiscalant dosage, the batch-treatment SWRO system of the present invention can be used to recovery water from silica-saturated RO concentrate without fouling the membranes. Silica concentrations of over 1,000 mg/L are attainable with relatively minimal pre-treatment of the silica-saturated feed solution.

Abstract: Equipment, systems, processes and techniques for conducting reverse osmosis processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.

Abstract: A method and apparatus for conditioning water is disclosed. Water is flowed past a probe, wherein the water may include impurities. The probe is energized to excite the water and a presence of electrons in the excited water is reduced to produce positively charged water downstream of the probe that causes the impurities to dissociate from the water. The excited water may be deposited on a soil for crop production. The excited water may be further deposited on the soil to flush impurities in the soil to a depth away from a root of a crop planted in the soil to reclaim the soil for crop production. The excited water may further be used to descale pipes, such as used in irrigation, heat exchangers, cooling systems, etc. In yet another embodiment, the probe may be energized at a frequency selected to destroy organism, thereby protecting ecosystems.

Abstract: A method and a system are provided for producing water from atmospheric air by contacting the air with an aqueous hygroscopic material in a contacting chamber and allowing a portion of the water from the air to be adsorbed into the aqueous hygroscopic stream. The adsorbed water is then subsequently separated from the hygroscopic material to provide a clean water stream and a reconstituted hygroscopic stream.

Abstract: An induced symbiotic osmosis pump (ISOP) (and method of using same) comprising: a closed loop comprising a riser pipe and a downpipe having substantially the same length fluidly communicating at a base with an induced osmosis semipermeable membrane and fluidly communicating at an opposed end with a brine pump fluidly communicating with a pressure exchanger fluidly communicating with a reverse osmosis membrane, the downpipe comprising a check valve; the induced osmosis semipermeable membrane of the closed loop fluidly communicating with an initial reverse osmosis module fluidly communicating with a brine pump fluidly communicating with a source of fluid having an initial salinity; the brine pump electronically communicating with an electrical source; and, the reverse osmosis membrane fluidly communicating with a storage tank.

Abstract: A multi-ported vessel system includes an outer pressure vessel containing a plurality of flow distribution tubes, each of which comprises a plurality of reverse osmosis membrane elements aligned serially within each tube. The outer pressure vessel includes bypass flow paths whereby feed water flows around each of the tubes within the vessel. Slots are disposed in the flow distribution tubes at the upstream end of each RO membrane element such that feed water reaches all RO membrane elements of the tubes in parallel. The serial alignment of the membranes also allows for serial water processing also. A product water tube collects the purified water from the reverse osmosis elements and provides it to a product water port. Brine water is provided to an output port to be discarded of for further processing. The parallel processing of feed water by all membrane elements results in increased productivity and reduced costs.

Abstract: An integrated process for removing sulfate from water sources, such as pretreated acid mine drainage (AMD). The multivalent cation (MVC) content of a sulfate stream is reduced by strong acid cation (SAC) ion exchange and sulfate is concentrated with a membrane system and separated as precipitate and overflow. Precipitation results from reaction of sulfate with MVC produced by regeneration of SAC with sodium chloride. The overflow is reacted with carbonate to precipitate MVC, generate sodium chloride and give a further overflow stream. This latter stream is concentrated to a level capable of being a regenerant for the SAC and when needed, used to regenerate the SAC and produce MVC for sulfate precipitation. The process minimizes the use of chemicals by treating, reconcentrating and recycling input species. Capital expenditures are minimized by precipitation of only side streams.

Abstract: The invention provides permeable magnetically responsive filtration membranes that include a filtration membrane polymer base suitable for fluid filtration; hydrophilic polymers conjugated to the surface of the filtration membrane polymer; and magnetic nanoparticles affixed to the ends of a plurality of the hydrophilic polymers, wherein the hydrophilic polymers are movable with respect to the surface of the filtration membrane polymer surface in the presence of an oscillating magnetic field.

Abstract: The invention provides a method and apparatus for continuous monitoring of permeate from membrane elements in a water treatment plant, including a desalination plant. The apparatus includes a probe that includes multiple sensors such that at least one sensor is associated with each membrane element. Each sensor is coupled to a node, which is configured to communicate a signal associated with the permeate quality to a central node sink. The node may communicate wirelessly with the node sink.

Abstract: Systems and methods for osmotically assisted desalination include using a pressurized concentrate from a pressure desalination process to pressurize a feed to the desalination process. The depressurized concentrate thereby produced is used as a draw solution for a pressure-retarded osmosis process. The pressure-retarded osmosis unit produces a pressurized draw solution stream that is used to pressurize another feed to the desalination process. In one example, the feed to the pressure-retarded osmosis process is impaired water.

Abstract: A process for preparing a reverse osmosis membrane that includes: (A) providing a polyamine, a polyfunctional acid halide, and a flux increasing additive having the formula Z+B? where Z+ is an easily dissociable cation and B? is a beta-diketonate; (B) combining the polyamine, polyfunctional acid halide, and flux increasing additive on the surface of a porous support membrane; and (C) interfacially polymerizing the polyamine and the polyfunctional acid halide, and flux increasing additive on the surface of the porous support membrane to form a reverse osmosis membrane comprising (i) the porous support membrane and (ii) a discrimination layer comprising a polyamide. The reverse osmosis membrane is characterized by a flux that is greater than the flux of the same membrane prepared in the absence of the flux increasing additive.

Abstract: Systems and methods for cleaning and disinfecting a medical therapy device that delivers any one of hemodialysis, hemodiafiltration and hemofiltration. The system has a base module that has at least one segment of a controlled compliant flow path and at least one pair of jumpered ports configured on the base module. One or more components have connections connectable to the jumpered ports of the base module to provide for fluid communication between the segment of the controlled compliant flow path in the base module and a flow path defined by the one or more components. The base module is connected to the one or more components that define a flow path configurable for carrying out in part at least one function performed during any one of hemodialysis, hemodiafiltration or hemofiltration.

Abstract: Systems and methods for the storage of potential energy that may be readily converted to electrical power delivered to a customer or grid distribution are disclosed. This method may involve the use of salinity gradients, or as they may be also described, osmotic pressure gradients or differences between two solutions, to produce hydraulic pressure in a concentrated solution, allowing for the generation of power.

Abstract: An embodiment of the present invention includes: a recycle line that brings a part of salt-enriched membrane separation concentrated water 26 back to the rear flow side of a pretreatment apparatus 12; a water discharge line that discharges the remained concentrated water into a sea area; and a control apparatus 31 that controls to adjust the ratio between the discharging amount of the discharging membrane separation concentrated water to be discharged into a sea area and the supplying amount of supplying seawater. A pH is set to be equal to or less than 7.3 by adding acid 21. The salt 18 is obtained from the dryer 19, and produced water (fresh water) 29 is obtained by combining evaporated water 28 supplied from the evaporator 16 with the permeated water 24 supplied from the reverse osmosis membrane apparatus 25.

Abstract: Disclosed herein are water purification and supply systems for medical devices and methods of using. In an embodiment, the system includes A dialysis system includes a filtration system capable of filtering a water stream, a water purification system capable of purifying said water stream in a non-batch process, a mixing system capable of producing a stream of dialysate from mixing one or more dialysate components with the water stream in a non-batch process, and a dialyzer system. The dialyzer may be a microfluidic dialyzer capable of being fluidly coupled to the stream of dialysate and a blood stream.

Abstract: The invention concerns a centrifugal filtering device for filtering a fluid. The device comprises a rotatable inner casing forming an inner space and a rotatable outer casing forming an outer space. The device further comprises a fluid inlet, at least one filter and drive means. The drive means is configured to rotate the inner casing to create a centrifugal pressure. The pressure forces a part of the fluid contained in the inner space through the filter and to a radially outer position of the outer space. The filtered fluid forms a filtrate, the filtrate having a kinetic energy. The outer casing is configured to transport the filtrate from the radially outer position to a radially inner position of the outer space, permitting transfer of the kinetic energy from the filtrate to the outer casing, thereby permitting regaining of mechanical energy.

Abstract: Described herein is a structure for a permeate spacer for use in spiral wound osmosis membrane elements, having at least two sets of parallel ribs, wherein the ribs in the first set are oriented at about a 90 degree angle to the ribs in the second set. The permeate spacer is used by sandwiching it inside a membrane envelope or leaf, and is particularly useful for non-pressure-driven processes, such as forward osmosis (FO) and pressure-reduced osmosis (PRO).

Abstract: High purity water produced by reverse osmosis. A feedwater is pretreated to remove hardness and non-hydroxide alkalinity, and the pH is raised to 8.5 or more to ionize solute species such as boron that are sparingly ionized when in neutral or near neutral pH aqueous solution. Ultrapure water resulting is suitable for industrial use.

Abstract: A method of purifying impure water contaminated with a filterable impurity and a dissolved impurity, such as seawater, comprising the steps of: providing impure water to a primary microfiltration or ultrafiltration unit to remove the filterable impurity and produce impure filtered water contaminated with a dissolved impurity; providing the impure filtered water contaminated with a dissolved impurity to a reverse osmosis unit to produce a potable water stream and a residual reverse osmosis stream; and treating the residual reverse osmosis stream prior to reuse. The treatment may be in the form of passing through a secondary filter (such as another microfiltration or ultrafiltration membrane or a cartridge filter, and the subsequently treated reverse osmosis reject may be used to backwash the microfiltration or ultrafiltration unit.

Abstract: A method of cleaning a membrane (6) in a membrane filtration system by flowing gas bubbles past the surfaces of the membrane (6) to scour accumulated solids therefrom. The method includes flowing a liquid past a supply of gas; creating a reduced pressure within the liquid flow to cause a flow of gas from the supply of gas (9) into the liquid flow and form gas bubbles therein and then flowing the liquid containing the gas bubbles past the surfaces of the membrane (6) to scour the surfaces thereof. Apparatus for performing the method is also disclosed.

Abstract: A potable water producing system for disposition at a body of salt water and a method of producing potable water is provided. The system includes a wave energy conversion system (AWECS) and a portable filtration-anchor system. The AWECS is in the form of a floating articulated barge housing a desalination system including a reverse osmosis membrane. The filtration-anchor system is submerged in the body of salt water and includes a sand filter to filter the adjacent salt water and to provide the filtered salt water to the desalination system on the articulated barge. The action of the waves on the articulated barge provides energy to pump the filtered salt water from the sand filter to the reverse osmosis member to produce potable water. Moreover, the action of the waves on the articulated barge effects the shaking of the reverse osmosis filter, thereby rendering it self-cleaning.

Abstract: A system, method, and apparatus for precipitating a water soluble salt or water soluble salts from water, including adding a water-miscible solvent to a water solution including an inorganic salt. The system, method and apparatus also allow for the separation of the precipitated salt, and for separation of the solvent from the water. In doing so, reclamation of water is provided.

Abstract: A process for treating a water stream containing dissolved organic carbon and dissolved salts comprises subjecting the water stream to reverse osmosis after a pre-treatment step to reduce the amount of dissolved organic carbon directed in water to the reverse osmosis treatment step. The preferred pre-treatment step is a membrane treatment step such as nanofiltration. The process enables treatment of complex effluents including mixtures of domestic and industrial effluents. Treated water may be recycled and a treatment plant (100) employing the process forms another aspect of the invention.

Abstract: A water treatment system including a reverse osmosis module and a control valve controlling communication between a water source and the module. A feedwater biased storage tank stores permeate and its pressurization by feedwater is controlled by a feedwater control valve. Flow of signal pressure to a signal pressure chamber of the feedwater control valve is restricted to reduce the rate at which a fluid generated force is applied. A check valve in parallel with the restriction allows relatively unrestricted flow out of the signal chamber when signal pressure is terminated. A tank pressurization control valve controls the operation of the feedwater control valve and controls the pressurization of a feedwater biasing chamber in the storage tank. Per-meate is stored in an accumulator for flushing the reverse osmosis module when the storage tank reaches a predetermined limit. Cleaning substances or additives can be introduced into the system.

Abstract: A system and method for removing gas from a gas producing subterranean formation and removing contaminants from the produced water is provided. The method includes providing a mixture of gas and water gathered from a gas producing well. Thereafter the method entails separating the gas from the mixture to produce a gas product and the produced water which includes organics, suspended solids and dissolved solids including silica. Thereafter, suspended solids are removed from the produced water. After removing some of the suspended solids, the produced water is directed to a micro porous polymer extraction (MPPE) unit. In the MPPE unit aromatic organic compounds are removed from the produced water. Thereafter the produced water is treated in a membrane bioreactor to remove additional organics. Thereafter the produced water is directed to at least one RO unit that produces a high dissolved solids containing reject stream and a low dissolved solids permeate stream.

Abstract: A purifying device and a process for deeply treating printing and dyeing wastewater are provided. The device includes a nanometer catalytic microelectrolysis system, a membrane filtration and separation system and a a membrane washing regeneration system. The method includes the following steps of: drawing the printing and dyeing wastewater by a first water pump (12), pumping a first part of the wastewater into a nanometer catalytic microelectrolysis tank (13) to perform catalysis microelectrolysis, and a second part of the wastewater into a neutralization tank (16) to mix with the water from the nanometer catalytic microelectrolysis tank (13) to precipitate, filtering the wastewater by a sand filtration tank (17), and then pumping the wastewater into an adsorption and filteration device of granular active carbon (18) for adsorption and filtration. The process has lower cost and higher energy efficiency, and can realize recycled water to be reused.

Abstract: A method is disclosed for estimating an optimal individual product water flow rate for a RO train in an RO unit. The RO unit includes a plurality of RO trains. The method can include providing a desired overall product water flow rate for the reverse osmosis unit followed by obtaining one or more dynamic characteristics for each RO train in the plurality of RO trains; estimating a minimal specific energy consumption value for each RO train using the one or more dynamic characteristics; and subsequently obtaining an optimal individual product water flow rate for each RO train.

Abstract: According to one embodiment, a apparatus includes a controller configured to obtain values measured by a first sensor and a second sensor, receive pH target values at the entrance of a first reverse osmosis membrane and at the entrance of a second reverse osmosis membrane, and use a transfer function from the acid injection to pH at the entrance of the first reverse osmosis membrane, a transfer function from the alkaline injection to pH at the entrance of the first reverse osmosis membrane, a transfer function from the acid injection to pH at the entrance of the second reverse osmosis membrane, and a transfer function from the alkaline injection to pH at the entrance of the second reverse osmosis membrane, to control an injection rate of the acid injected from a first injection device and an injection rate of the alkali injected from a second injection device.

Abstract: Described are water-on-water valves for use in reverse osmosis filtration systems. The water-on-water valves are regulated by the pressure in a product line, which contains fluid from a product line of the filter module and/or the product side of a water-on-water storage tank. Exemplary valves are shuttle valves that are regulated by the pressure downstream of the product side of a reverse osmosis filter module. The valves may comprise a piston within a housing, and an end of the piston may have an enlarged diameter relative to the maximum diameter of the remainder of the piston.

Abstract: A reverse osmosis element is provided. The reverse osmosis element includes a plurality of permeate tubes arranged to form a core frame. The reverse osmosis element further includes a plurality of leaves wound over the core frame. Each leaf of the plurality of leaves is coupled to one permeate tube of the plurality of permeate tubes. A retentate channel is defined by the plurality of permeate tubes of the core frame, and sealed by the plurality of leaves wound over the core frame. The reverse osmosis element includes first and a second end caps coupled to the plurality of permeate tubes. At least one of the first and the second end caps includes a retentate discharge port, and at least one of the first and second end caps includes one or more permeate discharge ports.

Abstract: A high efficiency water purification system is provided incorporating recovery of a portion concentrate wastewater associated with the reverse osmosis unit. This reduces the overall volume of concentrate wastewater requiring discharge/disposal by reusing the purified concentrate of a concentrate recovery units as RO feed water. Initial feedwater is pressurized and passed through an RO membrane, and separated into a permeate flow and a concentrate flow. A portion of the higher pressure concentrate is then directed to an additional set of thin film composite membranes (concentrate recovery membranes). The concentrate recovery membranes are arranged in an array such that the concentrate pressure is adequate to provide the force required to drive the concentrate through the recovery system membranes. The permeate produced by the concentrate recovery system is directed back to the feed of the primary RO unit; thereby, reducing the volume of raw feed water required for system operation.

Abstract: A reverse osmosis system and method of operating the same includes a first pump receiving feed fluid at a first pressure and increasingly pressurizing the feed fluid to a second pressure higher than the first pressure. A membrane housing having an inlet, a membrane, a permeate outlet and a brine outlet. The inlet receiving feed fluid. A hydraulic energy management integration system (HEMI) having a turbine portion, a pump portion and a motor. The brine outlet fluid is in fluid communication with the turbine portion. The reverse osmosis system also includes a second pump and a controller controlling the motor to retard rotation of the HEMI while the first pump increasingly pressurizes the feed fluid to the second pressure.

Abstract: Hydraulic fracturing produces backflow water that is high in total dissolved solids, hardness and silica. A system to treat backflow water has an electrical separation unit and a reverse osmosis (RO) unit. The electrical separation unit may comprise an electrodialysis device (ED), an electrodialysis reversal (EDR) device or a supercapacitive desalination (SCD) device, or a combination thereof. The electrical separation unit may be combined with a precipitation unit and reduces the TDS and hardness of the backflow water. The RO unit reduces the silica concentration of the backflow water. A pre-treatment unit may further condition backflow water treated in the electrical separation unit to inhibit fouling in the RO unit. The treated backflow water may be suitable for reuse in hydraulic fracturing or discharge.

Abstract: A high-pressure pump P1 that increases the pressure of raw water, a high-pressure reverse osmosis device including a high-pressure reverse osmosis membrane for concentrating a salt content in high-pressure feed water, a first drain valve mounted on a permeated water line for supplying the permeated water downstream and temporarily draining permeated water of an initial start-up from a discharge line, a low-pressure pump that is mounted on a permeated water line provided downstream of the first drain valve and reduces the pressure of the permeated water, a low-pressure reverse osmosis device including a low-pressure reverse osmosis membrane for concentrating a salt content in low-pressure feed water, and a second drain valve mounted on a discharge line at the concentrated water side of the low-pressure reverse osmosis device that temporarily discharges the low-pressure feed water of the initial start-up supplied to the low-pressure reverse osmosis device.

Abstract: Water treatment systems and methods are provided to minimize membrane fouling and the required maintenance that results therefrom. A water treatment system includes a pressure vessel with a plurality of spaced-apart membranes disposed therein, and an impeller or other means for circulating feed water through the interior of the vessel and past the membranes. Antifouling particles (such as diatomaceous earth or activated carbon) and/or pellets can be added to the feed water inhibit membrane fouling and extend the useful life of the membranes.

Abstract: A method of operating a capacitive deionization cell using a regeneration cycle to increase pure flow rate and efficiency of the cell.

Abstract: Disclosed herein are water purification and supply systems for medical devices and methods of using. In an embodiment, the system includes a dialysis system including a filtration system capable of filtering a water stream, a water purification system capable of purifying the water stream in a non-batch process, a mixing system capable of producing a stream of dialysate from mixing one or more dialysate components with the water stream in a non-batch process, and a dialyzer system. The dialyzer may be a microfluidic dialyzer capable of being fluidly coupled to the stream of dialysate and a blood stream. The water purification system includes an RO filter 6122, a proportioning valve 6165, a heater 6150, first and second heat exchangers, and a throttle valve 6160.

Abstract: Disclosed is an improved method for remineralizing desalinated water. The desalination system includes, but is not limited to, a conventional reverse osmosis membrane system, forward osmosis membrane system, electro dialysis system, Multi Stage Flash (MSF) system, and Multi Effect Distillation (MED) system.

Abstract: Disclosed is a versatile multi-use high water recovery process that integrates the use of water purification membranes including reverse osmosis and nanofiltration with ion exchange water softening resins in a number of configurations that optimize operation and achieve maximum membrane permeate recoveries while eliminating the use of fresh water, sodium chloride and other chemicals needed to regenerate the IX resin. The invention provides process mobility and flexibility that enable selection of optimum process configurations and features to address variability in the Influent Water quality.

Abstract: The invention relates to a method of treating water effluent from purging or cleaning steam generator circuits. In characteristic manner, the following steps are performed: filtering the raw effluent to separate insoluble matter from the filtered effluent; and concentrating the filtered effluent to below the solubility limit of the dissolved species so as to obtain a liquid concentrate, the concentration step including at least evapo-concentration treatment and reverse osmosis treatment; the pH of the effluent being adjusted to a value in the range 5 to 6.5.

Abstract: Systems, components, and methods for water purification are described. In an example, a system may comprise an array of light-focusing elements, a heat exchanger device, a turbine generator, or other components and can be configured to use a source of light (e.g., sunlight) to filter water from a water source and to generate electricity. The electricity may be looped back into the system to further produce filtered water.

Abstract: Aspects for utilizing a seawater fluid to optimize egg-production characteristics are disclosed. In one aspect, a method is provided, which includes identifying a desired optimization, determining a corresponding seawater to non-seawater ratio, and generating a seawater fluid according to the ratio. An egg-cultivation method is also provided, which includes ascertaining a desired optimization, selecting a corresponding seawater to non-seawater ratio, and providing a seawater fluid comprising the ratio to a hen. In another egg-cultivation method, hens are provided with a mixed feed comprising a feed to seawater-mineralized produce ratio selected according to a desired optimization. A method to grow produce is also provided, which includes mineralizing soil with a seawater fluid comprising a seawater to non-seawater ratio corresponding to a preferred optimization.

Abstract: A system and method for purifying and recycling cold wastewater is provided. Contaminated wastewater is supplied at a temperature no greater than 45° F. through an ultrafilter. The wastewater is fed through a reverse osmosis filter unit. Clean water is reused whereas reject is sent to disposal. Cold temperatures are preferably maintained throughout the treatment process.

Abstract: Brine disposal systems are configured to receive brine from a brine source and to passively collect seawater from a nearby ocean during high tide using one or more tidal forces. Tidal movements during high tide, low tide, or both may be used to mix and thereby dilute the brine with the seawater. The mixture of seawater and brine is then passively discharged into the ocean during low tide using the tidal force, thereby minimizing the impacts on the marine ecosystem.

Abstract: A process for removing a solvent from a source solution, said process comprising a) contacting the source solution with one side of a selectively permeable membrane, b) contacting a draw solution having a higher osmotic pressure (higher solute concentration) than the source solution with the opposite side of the membrane, such that solvent from the source solution passes across the membrane to dilute the draw solution by direct osmosis, c) removing solvent from the diluted draw solution to regenerate the draw solution, and d) recycling the regenerated draw solution to step a), characterized in that a portion of the draw solution is discarded or treated before and/or after the draw solution is regenerated in step c) so as to reduce the concentration of any solute species present in the draw solution from the source solution.

Abstract: A process for treatment of water. Hardness and non-hydroxide alkalinity are removed from feedwaters to an extent sufficient to avoid scaling when concentrated. Sparingly ionizable components in the feedwater are urged toward increased ionization by increasing the pH of the feedwater. In this manner, species such as silica become highly ionized, and (a) their rejection by membranes used in the process is significantly increased, and (b) their solubility in the reject stream from the membrane process is significantly increased. Sparingly ionized species such as boron, silica, and TOC are highly rejected. Recovery ratios of ninety percent (90%) or higher are achievable with many feedwaters, while simultaneously achieving a substantial reduction in cleaning frequency of membranes used in the process.

Abstract: A process for a purification of water with multiple contaminants including dissolved solids. The process may involve one or more steps of separating oil and water, metals precipitation, dissolved air flotation (DAF), filtration, forward or reverse osmosis and crystallization. An improved DAF unit is described which increases air dissolution to oxidize impurities and improve flotation. Various embodiments of staged osmotic membrane systems are provided to generate an essentially pure water stream and a highly concentrated solute stream. In some embodiments, reverse osmosis and nanofiltration units are employed in a staged manner. In other embodiments, all stages are reverse osmosis units and the osmotic pressure of each stage is adjusted by the provision of a solution on the low pressure side of the reverse osmosis membrane using nanofiltration membranes. Various recycle options are employed to improve the efficiency of the systems.

Abstract: This invention concerns a method for desalination of sea water and a design and construction of a centrifugal filter for desalination of water. The process uses the filter developed based on reverse osmosis technology as a fundamental component that uses hollow fiber membrane modules arranged in a spiral manner around a central support pipe and distributed in concentric rings around the periphery of the rotating section to favor the formation of Dean vortices. Wherein the membrane is built with a structure of an aromatic polyamide as the first layer, followed by a layer of polyestersulfone and a support layer of polyester; applying the material Kevlar 49 in position 1 and 4 on the aromatic chain structure to increase the structure and resistance of the membrane.