Systems and processes for production of industrial chemicals, metals, minerals, and water from salt brine

Abstract

The improved systems and processes are directed to recovery and utilization of salt brines, which are waste byproducts generated from municipal or industrial water treatment processes such as Reverse Osmosis, thermal desalination, or the like. These brines, typically characterized by high concentrations of dissolved salts, are processed to synthesize commercially valuable chemicals and enable water recovery for potable reuse. The invention integrates advanced separation, precipitation, and electrochemical techniques into a unified process achieving efficient resource recovery and waste minimization such that the resulting facility is Zero Liquid Discharge (ZLD). Core products derived from this process include hydrochloric acid (HCl) and caustic soda (NaOH). Additional products may include calcium sulfate (CaS04), magnesium hydroxide (Mg(0H)2), elemental magnesium metal, lithium hydroxide ( LiOH), lithium chloride ( LiCl), and a variety of rare earth elements (REEs). Additionally, the process recovers purified water for reuse in municipal or industrial applications.

Description

TITLE OF THE INVENTIONSystems And Processes For Production Of Industrial Chemicals, Metals, Minerals, And Water From Salt BrineTECHNICAL FIELD

[0001] The instant invention relates to water treatment systems and processes, specifically with the recovery and production of chemicals, metals, minerals, and potable or industrial use water from salt brines.BACKGROUND ART

[0002] Salt Brines contain diverse anions and cations though more typically, Sodium Chloride (NaCl) is the dominant constituent as a result of industrial or municipal desalination. These brines, particularly those associated with a groundwater source, typically contain other common constituents and these include: Calcium (Ca2 +), Magnesium (Mg2+), Bicarbonate (HC03), Sulfate (S042), Potassium (K+), Iron (Fe2+ / Fe3+), Manganese (Mn2+), Fluoride (F ), Arsenic (As), and Bromide (Br ) . There may also be a presence of Rare Earth Elements (REE's), Lithium (Li+), and other metals in ionic form.

[0003] Hydrochloric acid (HCl) is a vital chemical with numerous industrial applications. In the steel industry, it is employed for pickling processes, targeting the efficient removal of rust and scale. The oil sector utilizes HCl in well acidizing, aiming to enhance overall production yields. Moreover, its role is pivotal in the synthesis of various organic compounds.Additionally, its use for pH control is employed across multiple industrial sectors for effective neutralization tasks.

[0004] Caustic soda (NaOH) is employed in numerous industrial applications. Within the pulp and paper industry, it is used WUPWE . 1000. 01.00. IB . PCT 1during both pulping and bleaching operations . Its importance also extends to the chemical production industry, being crucial for synthesizing a range of organic chemicals . It is commonly employed in soap and detergent applications as well as its industrial use as a surfactant . In the Oil and Gas industry, NaOH is used broadly for certain refining and processing techniques .

[0005] Calcium sulfate (CaS04) serves a variety of critical roles across multiple industrial sectors . Predominantly, it is utilized in the construction industry as the primary ingredient in plasterboard, wallboards, and other plaster-based products, providing fire-resistant properties and aiding in sound insulation . Additionally, in the cement industry, gypsum acts as a setting regulator when mixed with Portland cement . The agricultural sector leverages gypsum as a soil conditioner, enhancing soil structure and preventing water runoff .

[0006] Magnesium hydroxide (Mg(0H)2) is a compound with a range of industrial applications . In the environmental sector, it is widely employed as a non-toxic alternative for wastewater treatment, aiding in neutralizing acidic effluents, odor control and removing heavy metals . Magnesium Hydroxide is also used in the plastics industry as a flame retardant for polymers, imparting enhanced fire-resistant properties . In pulp and paper production, its role as a pulping agent proves essential.

[0007] Elemental magnesium metal (Mg) is a lightweight, silver-white alkaline earth metal known for its high strength- to-weight ratio, corrosion resistance, and reactivity. It is primarily produced through the electrolysis of molten magnesium chloride derived from seawater, salt brines, or the reduction of magnesium oxide (MgO) from dolomite and magnesite. Magnesium is widely used in lightweight alloys for automotive and aerospaceWUPWE . 1000. 01.00. IB . PCT 2applications, as a reducing agent in chemical processes, and in emerging technologies like magnesium-ion batteries.

[0008] Lithium (Li), a lightweight and highly reactive alkali metal, has secured a foundational role in its application in the energy sector as a vital component of lithium-ion batteries. It is used to power a myriad of devices, from smartphones to electric vehicles, revolutionizing energy storage solutions.

[0009] Rare earth elements (REEs), comprising a set of seventeen chemical elements in the periodic table, are critical to a myriad of modern technologies and industries. Central to the electronics industry, REEs are integral to the manufacturing of high-performance magnets, which are vital in, for example, wind turbines and hard disk drives. In the realm of energy, they play a pivotal role in the production of hybrid and electric vehicle batteries, promoting sustainable transportation. The defense sector leverages them for advanced communication systems, guidance systems, and night vision equipment . Their unique luminescent properties also find application in the making of phosphors, which are essential in fluorescent lamps and LED screens. Moreover, they are employed in petroleum refining as catalysts to enhance the fracking process.

[0010] DESALINATION METHODOLOGY AND ORIGINS OF BRINES

[0011] Reverse osmosis (RO) is a widely employed membrane-based desalination technique used to produce fresh, potable water from saline sources such as seawater or brackish water. It relies on the principles of selective permeability through semipermeable membranes to separate water molecules from dissolved ions and other impurities. The desalination process begins by drawing in saline source water, typically from the ocean, through large intake structures or pipes. Prior to entering the RO system, the source water undergoes rigorous pre- treatment to eliminate suspended solids, organic matter, and potential fouling agents.WUPWE . 1000. 01.00. IB . PCT 3Processes include screening, sedimentation, coagulation, and disinfection . The pre- treated water is then pressurized using high-pressure pumps to create the necessary hydraulic force for the RO process . Pressure levels are typically in the range of 800 to 1, 200 psi (55 to 83 bar) depending on the specific RO system. The pressurized water is conveyed through a series of semipermeable RO membranes . These thin-film composite (TFC) or cellulose acetate membranes or other materials have nano-sized pores, typically in the range of 0.1 to 0.0001 microns, allowing water molecules to pass through while blocking the passage of ions, salts, and most impurities . As the saline water is forced through the RO membranes under pressure, water molecules permeate the membrane matrix, while dissolved salts, minerals, and contaminants are rejected . This separation process generates two streams : the purified, low-salinity permeate (freshwater) and the concentrated brine reject . The fresh permeate is further treated to adjust its pH, re-mineralize it, and disinfect it to meet drinking water quality standards . While the permeate clean water is the product from the desalination process, the concentrate brine is the feed source for the metal and minerals recovery process .

[0012] Thermal desalination processes such as multi-effect distillation (MED) and Multi-stage flash processes may also be used for desalination . Most commonly such processes are attached to power plants such that water is co-generated from the process . Thermal desalination processes utilize heat energy to convert saline water, including seawater or brackish water, into freshwater through evaporation and condensation .

[0013] Two widely used thermal desalination techniques are MultiEffect Distillation (MED) and Multi-Stage Flash (MSF) . Both processes exploit multiple stages for enhanced energy efficiency. Saline source water, typically seawater, isWUPWE . 1000. 01.00. IB . PCT 4initially drawn into the desalination plant through intake structures and subjected to preliminary pre- treatment . Pretreatment methods encompass screening, sedimentation, and filtration to remove suspended solids, algae, and impurities .

[0014] Both MED and MSF processes utilize multiple evaporation stages, commonly referred to as "effects" in MED and "stages" in MSF . These stages are organized sequentially, with each acting as a separate evaporator unit . An external heat source is a critical component of thermal desalination . The heat can be supplied through various means, such as steam, hot water, or waste heat from industrial processes, most commonly power plants . It initiates the evaporation process in the first effect or stage. In each effect or stage, the saline water is heated, causing it to evaporate. As vapor rises, it leaves behind dissolved salts and impurities, which results in the concentration of these substances in the remaining brine. In certain configurations, vapor produced in the first effect or stage can be compressed and sent to subsequent effects or stages as a heat source. This enhances energy efficiency by utilizing vapor for further evaporation . This is known as vapor compression . Vapor produced in the effects or stages is condensed into freshwater in separate condensers . The collected freshwater is the desired product water, ready for use. The concentrated brine, enriched with separated salts and impurities, is typically discharged back to surface or subsurface. As in the Reverse Osmosis process, while the permeate clean water is the product from the desalination process, the concentrate brine is the feed source for the metal and minerals recovery process .

[0015] FRAMING THE ENVIRONMENTAL CHALLENGES AROUND SALT BRINES

[0016] The global discharge of salt brines is 142 Billion Cubic Meters (115 Million Acre Feet) of brine annually, of which 55%WUPWE . 1000. 01.00. IB . PCT 5of brine discharges occur in the Middle East alone. The primary challenge associated with brine disposal is its potential environmental impact . The concentrated brine contains elevated levels of dissolved salts and minerals, making it denser than seawater . Discharging brine directly into marine ecosystems can disrupt local marine life and harm sensitive habitats, such as coral reefs and estuaries . The increased salinity and altered chemical composition can adversely affect marine organisms and disrupt the balance of coastal ecosystems .

[0017] Injecting desalination concentrates, or brine, into the ground poses significant environmental risks, primarily related to groundwater contamination and geophysical disturbances . The high salinity and concentration of dissolved minerals in brine can seep into freshwater aquifers, potentially rendering them unsuitable for human consumption, agriculture, or ecological functions . Additionally, brine often contains residual chemicals from the desalination process, such as anti-scalants, coagulants, and heavy metals, which may further degrade groundwater quality. Over time, the accumulation of such contaminants can create long- lasting challenges in managing subsurface water resources . Geophysical risks include increased pressure in injection wells, which may induce micro-seismic events or cause fractures in surrounding geological formations, further enhancing the risk of contaminant migration . Proper site selection, regulatory oversight, and advanced monitoring systems are critical to mitigating these risks and ensuring the safe disposal of brine into the ground .

[0018] METHODOLOGIES FOR MANAGING BRINES

[0019] Treatment methods for salt brine, which is a concentrated solution of salt and other dissolved impurities as described in the foregoing descriptions, are essential to manage and reduce their environmental impact . The choice of common treatmentWUPWE . 1000. 01.00. IB . PCT 6methodology depends on the composition of the brine, local regulations, and the specific goals of the treatment .

[0020] Dilution : One of the simplest methods for reducing the salinity of brine is dilution with freshwater . By mixing the brine with a large volume of freshwater, the overall salinity decreases . This method is frequently used in coastal areas where brine can be discharged into the ocean . However, this approach may not be suitable for highly concentrated brines, for very large volumes or inland locations .

[0021] Evaporation Ponds : Evaporation ponds are shallow, man-made basins where brine is allowed to evaporate under the sun ' s heat . As water evaporates, salts and other impurities are left behind and can be harvested or managed . Evaporation ponds are effective for brine with relatively high salinity levels and are often used in arid regions . However, this approach is effective only for relatively small desalination systems .

[0022] Membrane Technologies : Electrochemical Membrane processes such as electrodialysis can be employed to selectively remove ions and impurities from brine. These processes use catalyst enabled, ion-exchange membranes and bipolar electrodialysis membranes, to separate brine into a concentrate stream and a purified (permeate)stream, The typical technology employed in this application is the Electrodialysis Bipolar Membrane (EDBM) approach .

[0023] Crystallization : Crystallization is a method that involves controlled cooling or evaporation of brine to promote the formation of salt crystals . These crystals can be separated from the remaining brine, effectively concentrating the brine.Crystallization is suitable for brines with high salt content . It is generally a thermal process that results in a large quantity of residue remaining .WUPWE . 1000. 01.00. IB . PCT 7

[0024] Chemical Precipitation : Chemical precipitation involves the addition of chemicals to brine to induce the precipitation of specific salts . Once the salts have settled or formed solid particles, they can be separated from the treated brine. Common precipitating agents include lime, calcium chloride, and aluminum sulfate.

[0025] ZERO LIQUID DISCHARGE (ZLD) AND ITS IMPORTANCE

[0026] Zero Liquid Discharge (ZLD) is an advanced wastewater management strategy that eliminates liquid waste discharge from industrial processes, including desalination . In the context of desalination, ZLD aims to recover all usable water and valuable minerals or salts from brine, leaving only solid waste for disposal. This approach is driven by growing concerns over the environmental impacts of traditional brine disposal methods, such as direct discharge into marine ecosystems or injection into the ground . ZLD not only minimizes ecological harm but also aligns with sustainability goals by transforming waste into resources, making it an increasingly attractive solution for desalination facilities . However, While ZLD is achievable using crystallizers, the economic viability is limited if large quantities of solids remain following dewatering .

[0027] A ZLD system for desalination brine waste typically involves several advanced treatment stages . These systems begin with primary treatment to remove suspended solids and adjust chemical properties, followed by membrane-based technologies such as reverse osmosis (RO) or nanofiltration (NF) to recover as much water as possible. The concentrated brine is then subjected to thermal processes, such as evaporators or crystallizers, to extract valuable salts and produce solid waste. Techniques like Electrodialysis Bipolar Membranes (EDBM) and advanced ion exchange, may be integrated to enhance the recovery of high-value chemicals, including magnesium, lithium,WUPWE . 1000. 01.00. IB . PCT 8or rare earth elements. These systems are complex but provide the dual benefits of waste minimization and resource recovery, making them a cornerstone of sustainable desalination.

[0028] When the common constituents of groundwater can be removed and synthesized into industrial chemicals, the brine, which is typically viewed as a waste product, becomes a product of value. This shifts the market from a compliance driven wastewater market to a requirement driven chemical market . In addition, the water, which would ordinarily be discharged in the course of the disposal process, may be recovered thereby reducing water demand, particularly in water deficient areas such as the United States Southwest, Middle East and parts of Asia.SUMMARY OF THE INVENTION

[0029] This invention discloses a comprehensive system and process for the recovery, utilization, and conversion of saline brines, such as those derived from municipal and industrial water treatment processes including reverse osmosis (RO), nanofiltration (NF), and thermal desalination. The disclosed technology integrates advanced membrane separation, chemical precipitation, electrochemical conversion, and thermal concentration processes into a unified system, enabling the production of industrial-grade chemicals such as hydrochloric acid (HCl) and caustic soda (NaOH), as well as valuable byproducts including magnesium hydroxide (Mg(0H)2), gypsum (CaS04) and potable water. In addition, in other embodiments the system may produce lithium salts, rare earth elements (REEs), and Elemental Magnesium. The invention achieves Zero Liquid Discharge (ZLD), eliminating liquid and solid waste, thereby addressing critical environmental challenges posed by brine disposal while creating significant economic value through resource recovery.WUPWE . 1000. 01.00. IB . PCT 9

[0030] Due to their chemical composition in salt brines, the above cited chemicals do not have industrial value in and of themselves. To have value, the individual ions must be reordered in the method and process invention that is set out herein. The purpose of this invention is to produce the useful industrial chemicals cited below, to produce potable water for either municipal and industrial purposes and to reduce the discharge of pollutants into the environment .

[0031] The process begins with a primary nanofiltration (NF) unit that supersaturates sulfate and calcium ions in a concentrate stream while directing a permeate stream for downstream treatment . Supersaturated concentrates are treated in a gypsum precipitation subsystem, where controlled crystal growth occurs in a reactor tank equipped with anti-scalants, followed by solid- liquid separation using a hydrocyclone cyclonic separator. Magnesium hydroxide recovery is achieved through a vibratory shear membrane system, which mitigates silica scaling and enables the production of Mg(0H)2slurry suitable for industrial applications. The NF permeate and concentrate streams are then directed to a seawater reverse osmosis (SWRO) unit, where sodium chloride recovery is maximized by integrating multiple streams. The SWRO concentrate is pre- treated using ion exchange and chelating beds to reduce divalent ion concentrations to below 20 parts per billion (ppb), ensuring the protection of downstream electrodialysis bipolar membrane (EDBM) systems .

[0032] The purified sodium chloride concentrate is processed in the EDBM unit to produce Hydrochloric Acid (HCl) and Caustic Soda (NaOH) . Bipolar membranes dissociate water molecules into H+and OH” ions, directing the formation of hydrochloric acid and caustic soda in separate cell compartments. A chloride removal system further purifies the caustic soda to industrial-gradeWUPWE . 1000. 01.00. IB . PCT 10standards by eliminating residual chloride ions transported via the "ion cloud" effect . Concentration of both HCl and NaOH is achieved using multi-effect evaporators, enabling HCl to reach 35.2% concentration and NaOH to reach 50%. Azeotropic constraints are overcome by incorporating an azeotrope breaker, such as sulfuric acid or other chemical entrainers, during the evaporation process, allowing separation beyond azeotropic concentration limits .

[0033] The system incorporates energy-efficient designs, such as cascading heat utilization in multi-effect evaporation and low-pressure operation in specific stages, to minimize energy requirements . The integrated process recirculates depleted brine streams into the NF and SWRO systems, creating a closed- loop operation . This configuration ensures complete utilization of dissolved solids and recovers all water as potable or reusable industrial water . The invention is particularly applicable for brines with high salinity or complex compositions, offering a scalable solution for Reverse Osmosis desalination plants and thermal desalination plants .

[0034] By integrating these advanced processes, the disclosed invention distinguishes itself from existing technologies through its ability to recover multiple valuable products while achieving complete elimination of liquid and solid waste such that it is a Zero Liquid Discharge (ZLD) system. The invention addresses pressing environmental and industrial challenges, offering a transformative approach to brine management, resource sustainability, and economic efficiency.DESCRIPTION OF DRAWINGS

[0035] The accompanying drawing, which is incorporated in and constitutes a part of this disclosure, illustrates the various embodiments described . In the drawing :WUPWE . 1000. 01.00. IB . PCT 11FIG. 1 is a water treatment processing schematic depicting the inflows and outflows of fluids and solids of the various processing stages in relation to the equipment utilized in a first embodiment .WUPWE . 1000 . 01 . 00 . IB . PCT 12DESCRIPTION OF EMBODIMENTS

[0036] The following description refers to the accompanying drawings . Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or similar parts . While multiple illustrative embodiments are described herein, modifications, adaptations and other implementations are possible . For example, modifications, substitutions, or additions may be made to any components illustrated in the drawings . Additionally, the illustrative methods described herein may be modified by substituting, reordering, removing, or adding steps to the disclosed methods unless expressly stated otherwise . Accordingly, the invention is not limited to the disclosed embodiments and examples . Instead, the proper scope of the invention is defined only by the appended claims .

[0037] The invention presents an improved and novel system and process for the recovery and utilization of salt brines, which are waste byproducts generated from municipal or industrial water treatment processes such as Reverse Osmosis (RO) or thermal desalination . These brines, typically characterized by high concentrations of dissolved salts, are processed to synthesize commercially valuable chemicals and enable water recovery for potable reuse . The disclosed invention integrates advanced separation, precipitation, and electrochemical techniques into a unified process to achieve efficient resource recovery and waste minimization such that the resulting facility is Zero Liquid Discharge (ZLD) . The core products derived from this process are Hydrochloric Acid (HCl) and Caustic Soda (NaOH) . Since the composition of brines can vary, additional products may include Calcium Sulfate (CaS04), Magnesium Hydroxide (Mg(0H)2), Elemental Magnesium Metal, Lithium Hydroxide ( LiOH), Lithium Chloride ( LiCl), and a variety of Rare Earth ElementsWUPWE . 1000. 01.00. IB . PCT 13(REEs) . Additionally, the process recovers purified water for reuse in municipal or industrial applications.

[0038] In a first embodiment the process described herein allows the production of Hydrochloric Acid (HCl), Caustic Soda (NaOH), Calcium Sulfate (CaS04), Magnesium Hydroxide (Mg(0H)2) and potable water. Other embodiments can also be used for the production of Elemental Magnesium, Lithium Chloride and Rare Earth Elements (REEs) .

[0039] The process is configured in the following distinct sequence each of which forms a process "Stage" :° Stage 1: Metals and Minerals Recovery of Calcium Sulfate (CaS04) and Magnesium Hydroxide (Mg(0H)2) ;° Stage 2: Salt concentration and purification of dissolved Sodium Chloride (NaCl) ;° Stage 3: Electrochemical production of Hydrochloric Acid (HCl) and Caustic Soda (NaOH) using an Electrodialysis Bipolar Membrane system; and° Stage 4: Concentration and purification of Hydrochloric Acid (HCl) and Caustic Soda (NaOH) to high grade industrial chemical products readied for distribution.

[0040] Figure 1 is a water treatment processing schematic depicting the inflows and outflows of fluids and solids of the various processing stages in relation to the equipment utilized in a first embodiment . Fluids and solids utilized or produced in various processes include: clean-in-place (CIP) chemicals (102) ; miscellaneous utility / plant sources (114) ; return water (122) ; natural gas (128) ; brackish well water (154) ; reverse osmosis concentrate (166) ; sodium sulfate / calcium chloride (Na2S04 / CaCl2) (192) ; dry salt / brine (206) ; clean in place waste (106) ; evaporation pad solids (112) ; plant water (124, 126) ; caustic product (150) ; acid and caustic product (152) ; acid productWUPWE . 1000. 01.00. IB . PCT 14(188) ; silica (Mg(0H)2) solids (208) ; and gypsum or other solids (210) ; drift and evaporation losses (120) ; steam condensate (134) ; steam (136) ; EDBM caustic (142) ; EDBM acid (184) ; lean brine (160) ; chloride removal by-products (190) ; process steam (162) and purge acid (164) . Processing stages and equipment include: membrane systems (104) ; process cooling towers (116) ; EDBM cooling towers (118) ; blowdown recovery (108) ; evaporation pad (110) ; brackish water reverse osmosis (156) ; polishing reverse osmosis (158) ; demineralization reverse osmosis (130, 138) ; combined turbine and heat recovery steam generator (HRSG) (132) ; EDBM (140) ; chloride removal system (144) ; caustic concentration (146) ; acid concentration (186) ; plant water reverse osmosis (204) ; primary nanofiltration system (170) ; primary weak acid cation ion exchanger (172) ; primary degasifier (174) ; fluoride ion exchanger (176) ; secondary nanofiltration system (178) ; seawater reverse osmosis system (180) ; chelating ion exchange / silica ion exchange / arsenic ion exchange (182); precipitation stages (194, 196) ; secondary weak acid cation ion exchange (198) ; tertiary nanofiltration degasifier (200) ; and tertiary nanofiltration (202) .

[0041] Stage 1: Gypsum Process

[0042] Referring to Figure 1, the process begins with salt brine being received from a membrane desalination process such as a Reverse Osmosis (RO) desalination plant, a Membrane Distillation (MD) plant or a thermal desalination plant that employs processes such as Multi-Stage Flash (MSF), Multiple-Effect Distillation (MED), Vapor Compression (VC), or Solar Water Desalination (156, 166) . One of ordinary skill will readily understand how each of these technologies operates.

[0043] The salt brine is brought to super saturation levels using a nanofiltration (NF) system (170) . The nanofiltration system produces two streams: 1) a permeate stream consisting mainly ofWUPWE . 1000. 01.00. IB . PCT 15water with some other minor constituents which are subsequently reviewed herein; and 2) a concentrate stream where sulfates (S042) and calcium ions (Ca2+) are concentrated to a supersaturated state and stabilized using anti-scalants .

[0044] Unique in this process is that a nanofiltration system may be used as a molecular separation process to separate solids and salts from water molecules . In this application both the permeate and the concentrate are product streams . Both the permeate and the concentrate result in a product since all of the salts and water are recovered as a product through both permeate and concentrate streams, and consolidated . The function of the Primary Stage Nanofiltration system is to supersaturate the sulfates (S042) and calcium ions (Ca2+) into a single supersaturated concentrate stream where the gypsum can be precipitated out in a controlled manner as described in detail below. Once that is achieved, the permeate streams and concentrate streams may be brought together in Stage 2 processing .

[0045] The concentrate stream from first stage nanofiltration :

[0046] In such a supersaturated state, the concentrate solution must maintain a flow rate above approximately 4 feet per second (fps), failing which the dissolved materials may crash out of solution in an uncontrolled manner . Such an uncontrolled crash may fail to produce useful chemicals . In addition, an uncontrolled crash into a quiescent zone can result in the formation of gypsum rock within the piping, together with other constituents, that is difficult to remove and which could result in loss of equipment that is irrevocably seized with the gypsum rock. Accordingly, sustained flow, a narrow operating temperature range, and saturation control using anti-scalants is maintained . These variables are managed through a digital control process that is programmed into a Human MachineWUPWE . 1000. 01.00. IB . PCT 16Interface (HMI) . The HMI is in the form of computer operations having an HMI display, which is common to the understanding of one of ordinary skill.

[0047] From the nanofiltration system, the concentrate flow is directed into a reactor tank and the solution is seeded with gypsum (CaS04) crystals. The reactor tank is mechanically agitated such that this supersaturated solution remains in motion while gypsum crystals grow in the reactor. A portion of the flow ranging from approximately 5-30% is continually drawn from the reactor from which the resulting gypsum (CaS04) crystals are separated using a hydrocyclone. (194) The hydrocyclone concentrates the larger crystals while directing the remaining de-concentrate to the second stage precipitation process for Magnesium Hydroxide. The resulting gypsum (CaS04) slurry is then further concentrated using a centrifuge. (194) This centrifuge initially adds water that reduces the sodium chloride in the solids and then concentrates the crystals from a slurry to a solid. These solids are directed to a container or containment area for use as a product while the remaining liquid is directed to the second stage precipitation process (196) .

[0048] The Permeate Stream from the First Stage Nanofiltration to Second Stage Nanofiltration.

[0049] The permeate from the first stage nanofiltration is chemically stable since it does not contain sulfates, however, it will contain calcium ions. This permeate flow is first directed to a primary weak acid cation (WAC) ion exchange system (172) that removes hardness. This is followed by a degasifier to remove carbon dioxide (C02) (174) . From this point, the flow is directed towards a secondary (second stage) nanofiltration system (178) . The permeate from the secondary nanofiltration system is directed to Stage 2 and goes to a seawater reverse osmosis system (180) . Therefore, the permeate from the primaryWUPWE . 1000. 01.00. IB . PCT 17nanofiltration system flows to the secondary nanofiltration system following the aforedescribed ion exchange and degasification processes.

[0050] The concentrate from the secondary nanofiltration system may contain silica which is directed to the second stage precipitation process for the magnesium hydroxide solution.

[0051] Stage 1: Magnesium Hydroxide Process

[0052] The Stage 1 Gypsum Process describes the precipitation of the gypsum from the concentrate stream. Following the separation of the gypsum crystals in the hydrocyclones, there remains a liquid containing magnesium ions (Mg+), which is consolidated with both the silica from the secondary nanofiltration concentrate (178) and any remaining liquid from the centrifuges. These three streams are then dewatered to produce a slurry containing varying quantities of magnesium hydroxide, silica, and other minor but not relevant species (hereinafter referred to as a magnesium hydroxide slurry) .

[0053] The magnesium hydroxide slurry is chemically stable following the removal of the gypsum upstream. However, the dewatering of this slurry can be challenging. This is due to the fact that, as any slurry containing silica is dewatered, the silica will begin to come out of solution and adhere to surfaces with which it comes into contact . Therefore this solution must remain in either very high constant high flow conditions exceeding approximately 10 feet per second or in a highly turbulent state such that the propensity for the silica to adhere to surfaces is reduced. This approach may also be combined with material selections such as Teflon, PTFE, and polysulfone that provide additional resistance to silica scaling .

[0054] The dewatering of the magnesium hydroxide solution precludes conventional membrane processes. Dewatering approaches WUPWE . 1000. 01.00. IB . PCT 18can include the use of filters, settlers, chemical coagulation, and vibratory shear membrane separation. However, the method and process employed in this embodiment preferentially calls for the use of a vibratory shear membrane process whereby a high velocity flow condition takes place within a membrane housing, such that there remains no liquid contact between the solids in the flow stream and the surface of the membrane and surfaces of the membrane housing. This condition may be induced by creating a harmonic resonance within the membrane housing.

[0055] When the Magnesium Hydroxide has been dewatered, such dewatering is managed to a pumpable slurry having a concentration of approximately 25-55% This material is then a product that may be used for industrial applications such as an odor control chemical in wastewater lift stations, headworks, or in sewage lines. It may also be used for odor control in slaughterhouse wastes or similar applications.

[0056] The residual liquid from the dewatered magnesium hydroxide solution is the permeate from the vibratory shear membrane process (196) . If it is a physical settling in the form of deadend filtration, this will simply be the residual liquid following production of the magnesium hydroxide slurry.Following this second stage precipitation, the remaining liquid will go through a secondary Weak acid conditioner (WAC) (198), which is an ion exchange system for the removal of hardness, followed by a degasifier for the removal of C02(200), followed by a tertiary nanofiltration system (202) from which any residual sulfates are removed in a concentrate stream. The concentrate stream from this tertiary nanofiltration system is directed to the first stage gypsum precipitation (194) where it augments the production of gypsum. The permeate of the tertiary nanofiltration system (202) is directed to a seawater desalination system (180) .WUPWE . 1000. 01.00. IB . PCT 19

[0057] Stage 2: The Salt Concentration Process Using SWRO, Ion Exchange and Chelating

[0058] Referring still to Figure 1, a unique series of processes are employed for both the permeate stream of the primary nanofiltration system as well as the concentrate stream of the primary nanofiltration both being directed to a seawater reverse osmosis system (SWRO) following the removal of the gypsum and magnesium hydroxide / silica slurry through the series of processes heretofore described. It is unconventional to combine both a concentrate stream and permeate stream. However, both of these streams contain high quantities of sodium chloride (NaCl) together with minor quantities of other species in that SWRO feed. These combined streams form the feed streams to the SWRO (180) . The SWRO also produces a concentrate stream and a permeate stream.

[0059] Seawater Desalination System (SWRO) Concentrate

[0060] The primary function of the SWRO is to maximize the concentration of the concentrate stream as a feedstock for the electrodialysis (ED) process (182) . The SWRO produces a concentrate greater than approximately 60,000 parts per million (PPM) total dissolved solids (TDS) .

[0061] There are multiple points of feed to the SWRO (180) as follows: 1) the permeate originating from the primary nanofiltration system (170) following its previously described post- treatment (172, 174, optional 176, and 178) ; 2) the concentrate originating from the primary nanofiltration system (170) following precipitation of gypsum, magnesium hydroxide slurries and its previously described post- treatment (194, 196, 198, 200, and 202) ; 3) the deconcentrated salt solution following electrodialysis (ED) (140) upstream of the SWRO; and 4) the concentrate return from the upstream chloride removal system (CRS) (144) that removes chlorides from the caustic soda WUPWE . 1000. 01.00. IB . PCT 20(NaOH) such that it is of industrial "membrane grade" quality. A major innovation to this application is the consolidation, recirculation and recycling of all sources of sodium chloride (NaCl) in the system.

[0062] As stated, the SWRO concentrate is the raw material for the Stage 3 production of caustic soda (NaOH) and hydrochloric acid (HCl) via electrodialysis. However, it is critical to remove divalent ions from the electrodialysis feed stream.Divalent ions are chemical species that can form two chemical bonds, owing to their capacity to donate or share two electrons during chemical reactions. This characteristic arises because these ions have either two fewer or two more electrons than the number of protons in their nucleus, resulting in their distinctive bonding behavior. Common examples of divalent ions include calcium (Ca2+), magnesium (Mg2+), iron (Fe2+), barium (Ba2+), strontium (Sr2+), manganese (Mn2+), zinc (Zn2+), and copper (Cu2+) .

[0063] Divalent ion blinding is a significant challenge in the operation of electrochemical membranes, particularly in processes such as electrodialysis. The distinction between "fouling" and "blinding" is that the former may be cleaned or removed while the latter refers to an irrevocable loss of membrane area due to either permanent scaling or molecular bonding to the membrane surface. Divalent ions, such as calcium (Ca2+), magnesium (Mg2+), and barium (Ba2+), have a strong propensity to interact with the surface of membranes and form insoluble precipitates when they combine with anions like carbonate (C032) or sulfate (S042) . These precipitates obstruct ion exchange pathways, reduce membrane permeability, and impair overall membrane efficiency by reducing available membrane surface area. The deposition of such scale not only decreases the operational lifespan of the membranes but also increases theWUPWE . 1000. 01.00. IB . PCT 21energy demand of the process due to elevated resistance.Effective blinding management strategies, for example but not limitation, include pre- treatment of feedwater to remove divalent ions, periodic chemical cleaning, and operation of electrodialysis at lower current densities, are strategies that maintain optimal membrane performance.

[0064] Ordinary ion exchange processes are employed on reverse osmosis feedwater or in some cases, such as for ultra-pure water treatment applications, on permeates. The application of ion exchange on concentrates is unconventional but necessary for the removal of divalent ions. The ion exchange beds follow the SWRO (182) . Following the ion exchange, an additional safety factor for removal of divalent / trivalent ions is the use of chelating beds which are employed in an additional polishing function for the selective removal of any residual divalent ions (182) .Following this treatment, the level of divalent ions is typically below approximately 20 parts per billion (ppb) . This flow then forms the feedwater to the electrodialysis (ED) process .

[0065] Seawater Desalination System (SWRO) Permeate

[0066] The SWRO permeate has a salinity of less than approximately 300 parts per million (ppm) of total dissolved solids (TDS), and is suitable for industrial reuse or potable water applications. In those instances where National Sanitation Foundation (NSF) standards are applicable, the use and application of a NSF compliant "Polishing Reverse Osmosis System" (158) may be required and utilized. This necessity arises when the downstream material science is not NSF certifiable owing to the unusual operating configuration of the use of SWRO concentrate as a treated product and where the intent is to use the resulting pure water for potable purposes.WUPWE . 1000. 01.00. IB . PCT 22

[0067] Since the SWRO permeate is less than approximately 300 ppm TDS, a side stream is taken from the permeate line and is processed through a demineralizer (138) . The function of this demineralizer is to remove any potential scale forming materials. A second polishing demineralizer (130) may be utilized to ensure that no residual scale forming materials are present . Following demineralization, the water may be used for other applications such as for steam generation and for cooling tower blowdown (132) .

[0068] Stage 3: Electrodialysis with Bipolar Membranes (EDBM)

[0069] Electrodialysis with bipolar membranes (EDBM) is an advanced membrane-based electrochemical process designed to separate and recover valuable components from solutions while simultaneously producing acids and bases. It integrates the principles of conventional electrodialysis (ED) with the functionality of bipolar membranes to enable the conversion of salts into their corresponding acids and bases.

[0070] Referring still to Figure 1, in this embodiment, the conversion of sodium chloride (NaCl) to both caustic soda (NaOH) and hydrochloric acid (HCl) takes place within a membrane stack that is equipped with multiple electrochemical cells, each with an anode and cathode forming three flow chambers, each of which is separated by a series of membranes and spacers (140) . An electrochemical membrane stack refers to a series of cells that are created by assembling a series of spacers and membranes, which form cells, into a stack consisting of hundreds of such cells. This assemblage of stacked cells is put into compression for purposes of sealing the device and taken together is referred to as an "EDBM stack."

[0071] The membranes consist of two layers, an anion-exchange layer and a cation-exchange layer, separated by a water dissociation catalyst . When an electric field is applied across WUPWE . 1000. 01.00. IB . PCT 23the EDBM stack (140), water molecules at the bipolar membrane's interface dissociate into H+and OH-ions. Anions (e.g. , Cl ) move toward the H+ions to form acids (e.g. , HCl), and cations (e.g. , Na+) combine with OH ions to produce bases (e.g. , NaOH) . Cation-exchange membranes and anion-exchange membranes within the EDBM stack (140) direct the selective transport of ions, creating separate streams of acids, bases, and purified water.

[0072] In the EDBM stack (140), cation-exchange membranes allow positively charged ions (e.g. , Na+) to move toward the cathode, while anion-exchange membranes permit negatively charged ions (e.g. , Cl ) to move toward the anode. The H+ions produced by the bipolar membrane combine with the anions (e.g. , Cl ) to form acids (e.g. , HCl) (184), while the OH-ions combine with cations (e.g. , Na+) to form bases (e.g. , NaOH) (142) . There are therefore multiple streams through the EDBM stack (140) : 1) concentrate feed; 2) dilute caustic soda (142) ; 3) dilute hydrochloric acid (184) ; and 4) a deconcentrate, also known as "lean brine" (160) .

[0073] Electrodialysis (ED) operates by applying an electric field across a solution, causing ions to migrate through ion-selective membranes toward oppositely charged electrodes.Positively charged ions (cations) move toward the cathode, while negatively charged ions (anions) migrate toward the anode. This movement is facilitated by cation-exchange membranes (CEMs) and anion-exchange membranes (AEMs), which selectively allow the passage of their respective ions while blocking others. However, under certain conditions, ions can deviate from their intended pathways due to phenomena known as ion drag and the influence of the "ion cloud." An ion cloud forms around a migrating ion, composed of oppositely charged counterions that are attracted to it . When the electric field drives this ion cloud rapidly through the solution, it may exert a dragging force on nearby ions, sometimes pulling them toward the wrong electrode. ThisWUPWE . 1000. 01.00. IB . PCT 24phenomenon, combined with other effects like diffusion and concentration gradients, can disrupt the ideal selective transport of ions. The chloride removal system (144) removes these negative chloride ions from the caustic soda solution such that the caustic soda purity is to a higher industrial grade and therefore of more value.

[0074] In electrodialysis processes for the production of caustic soda (sodium hydroxide) and hydrochloric acid from sodium chloride, the current density plays a critical role in determining the efficiency and concentration of the resulting products. Current density, measured as the electric current per unit membrane area (i.e. , amperes per square meter), directly influences the rate of ion migration across the membranes. To achieve product concentrations in the range of approximately 3% to approximately 8% for caustic soda and hydrochloric acid, typical current densities are maintained within a range of approximately 100 to approximately 500 amperes per square meter, depending on system design and operational parameters. Lower current densities (near approximately 100 A / m2) are often used for achieving steady, lower-concentration outputs, while higher current densities (up to approximately 500 A / m2) are applied to accelerate ion dissociation and concentrate the products more rapidly. The higher the current density the greater the concentration of the product solution but at a cost of relatively lower membrane life and relatively inefficient transport of ions.

[0075] However, operating at higher current densities introduces challenges such as increased energy consumption, membrane heating, a more intense "ion cloud" and ion depletion near the membrane surface, which can lead to concentration polarization and reduced efficiency. Effective management of these conditions requires careful optimization of flow rates, brine composition,WUPWE . 1000. 01.00. IB . PCT 25and pre- treatment to ensure stable operation. Additionally, the membrane stack design must support uniform ion distribution and minimize resistance. Bipolar membranes, which dissociate water molecules into H+and OH-ions, are especially sensitive to current density, as excessive values can cause local overheating or fouling, impacting the quality of the acid and base products. By maintaining current density within the optimal range and ensuring proper system monitoring, consistent product concentrations of approximately 3% to approximately 8% can be achieved while preserving operational efficiency and membrane longevity .

[0076] Another beneficial aspect of this invention is its closed-loop configuration, wherein depleted brine is recirculated to the SWRO system (180) and augmented with incoming brine originating at the primary NF (170), therefore allowing for continuous and automated operation of the plant . This recirculation allows for the consumption of all of the Sodium Ions Na+and Chloride Ions Cl’, to be converted to useful industrial products.

[0077] This embodiment offers a comprehensive solution for the utilization of salt brines, enabling the extraction of valuable chemical products, water recovery, and the recycling of waste streams. By integrating innovative separation and synthesis technologies, the invention addresses key industrial challenges related to waste management, resource sustainability, and environmental stewardship.

[0078] Stage 4: Concentration of Hydrochloric Acid (HCl) and Caustic Soda (NaOH)

[0079] Hydrochloric Acid Concentration

[0080] Referring still to Figure 1, following the production of a dilute solution of hydrochloric acid in the EDBM (140), theWUPWE . 1000. 01.00. IB . PCT 26solution is transferred to a hydrochloric evaporator which includes an azeotrope breaker (186) .

[0081] Concentrating a dilute solution of hydrochloric acid (HCl) from approximately 3-5% to approximately 35.2% requires a thermal distillation process with two effects and the inclusion of an azeotrope breaker to overcome the separation challenges posed by the azeotropic behavior of HCl and water . HCl forms an azeotrope with water at approximately 20.2% concentration, where the mixture exhibits a constant boiling point, preventing further separation by conventional distillation . An azeotrope breaker disrupts this behavior, allowing the concentration process to continue to higher concentrations .

[0082] In the first effect, the dilute HCl solution is fed into a heated distillation chamber where thermal energy (for example but not limitation, steam) is applied . The steam (162) is produced from pure water from the SWRO (180) as previously described . Heat causes water to evaporate preferentially, concentrating the HCl to near its azeotropic limit of approximately 20%. At this stage, an azeotrope breaker, such as a carefully dosed entrainer (for example but not limitation, sulfuric acid or another suitable dehydrating agent), is introduced into the system. The azeotrope breaker alters the boiling characteristics of the solution, shifting the azeotropic composition and enabling further separation .

[0083] The concentrated solution, now free from the azeotropic constraint, enters the second effect, which operates under reduced pressure to lower the boiling point of water and enhance energy efficiency. This low-pressure distillation further removes water, achieving the target HCl concentration of approximately 35.2%. Vapors from both effects, primarily water, are condensed and removed as separate streams . The azeotrope breaker ensures high separation efficiency, enabling the systemWUPWE . 1000 . 01 . 00 . IB . PCT 27to surpass the azeotropic limit and produce a highly concentrated, essentially pure HCl product . This approach combines the benefits of thermal distillation and azeotropebreaking chemistry, ensuring effective and energy-efficient concentration of hydrochloric acid.

[0084] Once the desired acid concentration is achieved, typically approximately 30% or greater, the solution may be transferred to an acid product tank where the material is held pending use (188) .

[0085] Caustic Soda Concentration

[0086] A process for concentrating a dilute solution of sodium hydroxide (NaOH) from an initial concentration of approximately 3-5% to a final concentration of approximately 50% comprises a chloride removal system (144) followed by a three-effect evaporation system (146) . The chloride removal system (144) eliminates residual chloride ions introduced during electrodialysis bipolar membrane (EDBM) processing (140) . The removal of the residual chlorides may provide a more valuable industrial product .

[0087] The purified NaOH solution is then fed into the first evaporation effect, where thermal energy, supplied through steam, is applied to evaporate water preferentially under controlled temperature and pressure conditions of approximately 280-320 degrees Fahrenheit and pressures in the range of approximately 75-90 psi. This effect concentrates the solution to approximately 15-20%. The partially concentrated solution is transferred to the second evaporation effect, which operates at a lower pressure of approximately 30-40 psi and temperatures ranging from approximately 100-120 degrees Fahrenheit to reduce the boiling point of water, minimizing energy consumption and thermal degradation of NaOH. This stage concentrates the solution to approximately 30-35%. Finally, the solution enters WUPWE . 1000. 01.00. IB . PCT 28the third evaporation effect, where water is further removed under reduced pressure and temperatures ranging from 80-90 degrees Fahrenheit to achieve a final NaOH concentration of approximately 50%. The cascading thermal energy from earlier effects optimizes energy recovery and efficiency. This integrated process of chloride removal and staged evaporation ensures the production of high-purity, concentrated NaOH suitable for industrial and chemical applications. Once the desired caustic soda concentration is achieved, typically approximately 40-50% or greater, the solution may be transferred to a caustic soda product tank where the material is held pending use (150) .

[0088] Clauses that describe particular aspects of embodiments of the instant invention follow.

[0089] Clause 1: A method for the comprehensive recovery and utilization of salt brines, comprising: treating a brine feed with nanofiltration (NF) system to produce a supersaturated concentrate stream containing sulfate and calcium ions stabilized with anti-scalants and a permeate stream directed for secondary treatment; applying a nanofiltration system where both the permeate and concentrate are used and both are used as product streams; precipitating gypsum from the supersaturated concentrate in a reactor tank, controlling crystal growth through seeding, temperature regulation, and anti-scalant dosing, and separating gypsum solids using a hydrocyclone followed by a centrifuge to render a solid gypsum product; recovering magnesium hydroxide from the residual concentrate stream using vibratory shear membrane technology to minimize silica scaling and maintain turbulence; directing both permeate and concentrate streams from the Primary NF unit, followed by a series of of additional processes into a single seawater reverse osmosis (SWRO) system to maximize sodium chloride recovery whileWUPWE . 1000. 01.00. IB . PCT 29rejecting precipitated solids; pre- treating the SWRO concentrate stream with ion exchange and chelating beds to reduce divalent ion concentrations to below approximately 20 ppb; converting sodium chloride from the pre-treated brine into hydrochloric acid (HCl) and caustic soda (NaOH) using an electrodialysis bipolar membrane (EDBM) system, wherein bipolar membranes dissociate water molecules into H+and 0H“ ions, creating separate product streams; removing chloride ions from the caustic soda stream using a purpose designed chloride removal system in a modified ion exchange process; concentrating the hydrochloric acid using multi-effect evaporators to a final concentration of less than approximately 30-35% and an azeotrope breaker in the first effect; concentrating caustic soda by first removing chlorides using a chloride removal system (CLS) followed by multi-effect evaporators to achieve a concentration of between approximately 40% to approximately 60%; recirculating depleted brine streams from downstream processes into the NF system feed to achieve zero liquid discharge (ZLD), ensuring complete utilization of dissolved solids; and recovering commercial-grade industrial products, including magnesium hydroxide, gypsum, hydrochloric acid, caustic soda, and potable or reusable water .

[0090] Clause 2 : The method of clause 1, wherein the nanofiltration system operates at flow velocities equal to or greater than approximately 4 feet per second, in vessels that are highly agitated and within a controlled temperature range to prevent premature precipitation of supersaturated constituents .

[0091] Clause 3: The method of clause 1, wherein the reactor tank in the gypsum precipitation subsystem is equipped with automated controls for temperature, flow rate, and anti-scalant dosing to optimize crystal growth and separation efficiency.WUPWE . 1000. 01.00. IB . PCT 30

[0092] Clause 4: The method of clause 1, wherein the magnesium hydroxide recovery subsystem employs chemically resistant materials, including polytetrafluoroethylene (PTFE) or polysulfone, to prevent adhesion of silica and other scaling agents .

[0093] Clause 5: The method of clause 1, whereby a vibratory shear membrane technology is employed to concentrate gypsum to a slurry without scaling tanks or piping.

[0094] Clause 6: The method of clause 1, wherein the SWRO system integrates both NF concentrate and permeate streams, balancing osmotic pressure to enhance sodium chloride recovery while minimizing energy consumption.

[0095] Clause 7: A method whereby the use and application of industry standard Reverse Osmosis membranes is reversed. Where normally the desalinated permeate stream is the product, the concentrate stream serves as the stream that is used to produce caustic soda and hydrochloric acid and the permeate stream produces water that is recovered for potable water or industrial purposes .INDUSTRIAL APPLICABILITY

[0096] The instant invention is industrially applicable to wastewater treatment, specifically in the recovery and production of industrial chemicals, metals, and minerals from the treated salt brines.WUPWE . 1000. 01.00. IB . PCT 31

Claims

CLAIMSI claim:Claim 1 A system for recovery of salt brines from wastewater with zero liquid discharge, the system comprising:a plurality of nanofiltration units receiving a salt brine, the nanofiltration units producing from the salt brine a permeate stream and a concentrate stream, the concentrate stream including a supersaturation of sulfates and calcium ions;at least one mineral precipitation unit for receiving the concentrate stream at a flow rate of at least approximately 4 feet per second to produce a gypsum slurry therefrom;at least one dewatering unit receiving the concentrate stream to produce a magnesium hydroxide slurry and a residual liquid stream therefrom;at least one seawater reverse osmosis (SWRO) unit receiving the permeate stream and the concentrate stream to maximize the concentration and to produce an SWRO outflow therefrom;at least one concentrate side Ion Exchange and chelating polishing unit receiving the SWRO outflow to produce a feedwater therefrom;at least one electrodialysis bipolar membrane (EDBM) unit receiving the feedwater and producing an EDBM acid and an EDBM base therefrom;WUPWE . 1000. 01.

00. IB . PCT 32and one or more recirculation pathways adapted such that no salt brine is discharged.Claim 2 The system of Claim 1, the mineral precipitation unit comprising :at least one reactor tank receiving the concentrate stream and growing gypsum crystals therefrom;at least one hydrocyclone unit for concentrating the grown gypsum crystals to produce a gypsum slurry; andat least one centrifuge for further concentrating the gypsum slurry into a gypsum solid.Claim 3 The system of Claim 1 comprising:at least one WAC ion exchange unit receiving the permeate stream; andat least one degasifier for removal of carbon dioxide from the permeate stream.Claim 4 The system of Claim 1, the at least one dewatering unit comprising:at least one vibratory shear membrane separation unit .Claim 5 The system of Claim 1, the at least one dewatering unit comprising:at least one vibratory shear membrane separation unit; andWUPWE . 1000. 01.

00. IB . PCT 33a harmonic resonance generator within the vibratory shear membrane unit to impart a harmonic resonance therein .Claim 6 The system of Claim 1 comprising :a thermal distillation unit receiving the EDBM acid to produce a concentrated acid .Claim 7 The system of Claim 1 comprising :a chloride removal unit followed by a three-effect evaporation system to produce a concentrated base.Claim 8 A method for recovery of salt brines from wastewater with zero liquid discharge, the method steps comprising :treating a salt brine feed with a plurality of first nanofiltration units to produce a concentrate stream and a permeate stream;treating the concentrate stream and the permeate stream with a second nanofiltration unit;precipitating the concentrate stream to recover gypsum therefrom;recovering magnesium hydroxide from the concentrate stream utilizing at least one vibratory shear membrane separation unit;treating the concentrate stream and the permeate stream with at least one seawater reverse osmosis unit to produce an SWRO concentrate stream therefrom;WUPWE . 1000. 01.

00. IB . PCT 34pre-treating the SWRO concentrate stream with ion exchange and chelating beds to reduce divalent ion concentrations ;converting sodium chloride from the pre-treated SWRO concentrate stream into an EDBM acid and an EDBM base using an electrodialysis bipolar membrane (EDBM) system;removing chloride ions from the EDBM base stream using a modified ion exchange process; andrecirculating the concentrate stream and the permeate stream from downstream processes into the plurality of first nanofiltration units to achieve zero liquid discharge .Claim 9 The method of Claim 8 comprising:pre-treating the SWRO concentrate stream with ion exchange and chelating beds to reduce divalent ion concentrations to below approximately 20 ppb.Claim 10 The method of Claim 8, wherein the EDBM acid is hydrochloric acid and the EDBM base is caustic soda.Claim 11 The method of Claim 8 comprising:wherein the EDBM acid is hydrochloric acid, concentrating the EDBM acid, using a multi-effect evaporator and an azeotrope breaker, to a final concentration of approximately 35% or less.Claim 12 The method of Claim 8 comprising:WUPWE . 1000. 01.

00. IB . PCT 35wherein the EDBM acid is hydrochloric acid, concentrating the EDBM acid, using a multi-effect evaporator and an azeotrope breaker, to a final concentration of less than approximately 30-35%.Claim 13 The method of Claim 8 comprising:wherein the EDBM acid is hydrochloric acid, concentrating the EDBM acid, using a multi-effect evaporator and an azeotrope breaker, to a final concentration of approximately 35.2%.Claim 14 The method of Claim 8 comprising:wherein the EDBM base is caustic soda, concentrating the EDBM base by first removing chlorides using a chloride removal system followed by multi-effect evaporators to achieve a concentration of between approximately 40% to approximately 60%.Claim 15 The method of Claim 8 comprising:recovering from the salt brine feed at least one commercial-grade industrial product chosen from the group consisting of : calcium sulfate; magnesium hydroxide; magnesium; lithium hydroxide; lithium chloride; gypsum; hydrochloric acid; caustic soda; and potable water.WUPWE . 1000. 01.

00. IB . PCT 36

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