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WO2025240958A1 - Total brine extraction using a vacuum membrane distillation – integrated crystallization reactor (vmd-icr) system - Google Patents

Total brine extraction using a vacuum membrane distillation – integrated crystallization reactor (vmd-icr) system

Info

Publication number
WO2025240958A1
WO2025240958A1 PCT/US2025/029981 US2025029981W WO2025240958A1 WO 2025240958 A1 WO2025240958 A1 WO 2025240958A1 US 2025029981 W US2025029981 W US 2025029981W WO 2025240958 A1 WO2025240958 A1 WO 2025240958A1
Authority
WO
WIPO (PCT)
Prior art keywords
salt
vmd
micron
exemplary embodiment
membrane
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/US2025/029981
Other languages
French (fr)
Inventor
Seyed B. SADR GHAYENI
Matt Heath NARROL
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kmx Technologies Inc
Original Assignee
Kmx Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kmx Technologies Inc filed Critical Kmx Technologies Inc
Publication of WO2025240958A1 publication Critical patent/WO2025240958A1/en
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/36—Pervaporation; Membrane distillation; Liquid permeation
    • B01D61/364—Membrane distillation
    • B01D61/3641—Membrane distillation comprising multiple membrane distillation steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/36—Pervaporation; Membrane distillation; Liquid permeation
    • B01D61/366—Apparatus therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/58—Multistep processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/26—Treatment of water, waste water, or sewage by extraction
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/442—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by nanofiltration
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/447—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by membrane distillation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/04—Specific process operations in the feed stream; Feed pretreatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/06—Specific process operations in the permeate stream
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/26—Further operations combined with membrane separation processes
    • B01D2311/2643—Crystallisation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2317/00—Membrane module arrangements within a plant or an apparatus
    • B01D2317/02—Elements in series
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/027—Nanofiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/14—Ultrafiltration; Microfiltration

Definitions

  • the present disclosure relates generally to the field of water purification. More particularly, the present disclosure relates to methods of concentrating brine streams and related systems. More specifically, the present disclosure relates to methods and systems for concentrating and separating salts and other dissolved solids from a water stream. The methods and systems are useful to treat water streams such as ground water, surface water, drinking water, wastewater, industrial process water, cooling water, and the like. BACKGROUND [0002] The water supply of various parts of the world is precarious.
  • an exemplary embodiment of the present disclosure may provide a process of purifying water comprising: providing an aqueous liquid feed stream comprising at least one salt; concentrating the at least one to near saturation or greater; crystallizing the at least one salt out of the feed stream to produce a slurry of the at least one salt; and separating salt crystals from the salt slurry.
  • an exemplary embodiment of the present disclosure may provide an integrated crystallization reactor (ICR) comprising: a vacuum membrane distillation system; a separation system selected from the group consisting of coarse filtration, microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO), and a hydrocyclone (HC).
  • ICR integrated crystallization reactor
  • MF microfiltration
  • UF ultrafiltration
  • NF nanofiltration
  • RO reverse osmosis
  • HC hydrocyclone
  • the disclosure provides a distillation apparatus including: a vacuum membrane distillation bundle; an integrated crystallization reactor comprising a chamber housed within a double walled generally cylindrical body, an inlet and an outlet; and a hydrocyclone with inlet and outlet lines, or a MF or a UF or a NF membrane system, preferably tubular membranes, capable of working at high solid loads (high density).
  • a double walled reactor defining a cavity or reaction space and having a liquid between the walls.
  • a tank with a cooling jacket is provided to reduce the temperature make larger and denser crystals and to accelerate precipitation without using a membrane system.
  • the temperature may be raised instead of lowered.
  • the disclosure provides: a process of purifying saltwater containing at least one salt, comprising: introducing the salt water into a pretreatment device selected from the group consisting of reverse osmosis, ultrafiltration, nanofiltration and microfiltration to afford a first permeate; transferring the first permeate to a VMD unit; transferring the concentrate from the VMD unit to a double-walled crystallization reactor, the reactor comprising a cooling jacket, in reciprocal fluid connection with the VMD unit to afford a supersaturated salt solution; transferring a high quality permeate product to be reused and fed into potential potable water streams; transferring the supersaturated salt solution to a cyclone to separate at least a portion of the salt from the supersaturated solution; and recycling at least a portion of the supersaturated solution to the VMD unit.
  • a pretreatment device selected from the group consisting of reverse osmosis, ultrafiltration, nanofiltration and microfiltration to afford a first permeate
  • a VMD unit transferring the concentrate from
  • Yet another aspect of the disclosure is a process of extracting salts from a feed water, comprising: providing a feed stream including at least one dissolved salt; introducing the feed stream to at least one VMD unit, to afford at least one of a (i) permeate, (ii) a high purity water and (iii) seepage; wherein the VMD underflow is transferred to a separation process including at least one UF system and one ultrafiltration tank; and wherein the ultrafiltration reject/overflow is transferred to a crystallization process including at least one crystallizer tank.
  • Page 2 of 56 232614 Another aspect of the disclosure is a process of salt crystallization and separation, comprising: providing a liquid feed stream comprising a solution of at least one salt; concentrating the solution to near saturation (for example, at least 60%, for example at least any of the following: 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5%, 99.9%); crystallizing the at least one salt out of the feed stream to produce a slurry of the at least one salt; and separating salt crystals from the salt slurry.
  • the process provides that pure water is also produced.
  • pure water includes substantially fully separated salts, that is, TDS (total dissolved solids) at an amount of less than 1000 ppm, less than 900ppm, less than 800ppm; less than 700 ppm; less than 600 ppm; less than 500 ppm; less than 400 ppm; less than 300 ppm; less than 200 ppm; less than 100 ppm; less than 75 ppm; less than 50 ppm; less than 25 ppm; less than 10 ppm; or less than 5 ppm.
  • TDS total dissolved solids
  • concentrating the at least one salt is performed by vacuum membrane distillation to produce a concentrated feed stream.
  • crystallizing the at least one salt comprises adjusting the temperature of the concentrated feed stream and/or of the crystallizer until at least a portion of the least soluble salt precipitates out of solution.
  • separating salt crystals from the salt slurry comprises at least one selected from ultrafiltration, hydrocyclone filtration, coarse filtration, microfiltration and nanofiltration.
  • a hydrophobic porous membrane is used for vacuum membrane distillation.
  • coarse filtration may involve filters having pore sizes of 10 microns to 2000 microns, 50 microns to 1000 microns, 100 microns to 500 microns, and values within the foregoing ranges.
  • the hydrophobic porous membrane has a pore size of less than 0.5 micron, preferably Page 3 of 56 232614 about 0.05 micron to about 0.45 micron, preferably about 0.2 micron to about 0.45 micron, preferably about 0.25 micron to about 0.45 micron.
  • concentration is carried out by a system that includes at least one of a concentrator, crystallizer and a separator, wherein the concentrator concentrates at least one salt in the solution to at least near saturation.
  • the system includes at least one concentrator and at least one of a crystallizer and a separator.
  • near saturation is defined as, for example, at least 60%, or for example at least any of the following: 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5%, 99.9% of saturation or other values in between the foregoing.
  • a definition of "near saturation” or another useful parameter in certain embodiments of the disclosure is a concentration greater than the saturation concentration of the crystallizer but not necessarily greater than the saturation concentration of the concentrator.
  • the "near saturation concentration” is also greater than the saturation concentration of the concentrator.
  • the concentrator operates at conditions independent of the operating conditions of the crystallizer.
  • the process further comprises transferring the solution to the separator where the crystals are removed from the solution.
  • the solution is saturated for at least one salt relative to the crystallizer conditions, but below saturation relative to the conditions of the concentrator.
  • the process comprises transferring or recycling the solution to the concentrator.
  • the repetition or cycling of the steps of Page 4 of 56 232614 concentration, crystallization and separation can continue as the salts are precipitated in order of least soluble to most soluble.
  • the products are a series of separated salts, purified water and a solution containing the most soluble salt. Further concentration, crystallization and separation steps can be undertaken until all salts and all dissolved solids are substantially fully separated or removed from the intake feed. Alternatively, the process can be continued to the end product or terminated earlier leaving a solution containing a mixture of the most soluble salts.
  • Salts may also be coprecipitated producing a mineral that is a mixture of more than one salt, for example under the right conditions NaCl and KCl will coprecipitate.
  • the salts may be separated by additional processing or left as a mixture of salts depending on the processing requirements.
  • the temperature within the crystallizer unit will be adjusted to a temperature causing the solution to be supersaturated. Additionally, time will be allowed for crystals to form.
  • the process further includes filtering the temperature-adjusted concentrated feed stream to afford salt crystals and permeate.
  • the process further includes entering the permeate into a VMD stage.
  • the process further includes filtering the concentrated feed stream to produce a slurry of at least one salt and a solution of at least a second salt. In this exemplary embodiment or another exemplary embodiment, the process further includes producing a mixture of dissolved solids and precipitated solids.
  • Another aspect of the disclosure is a process for salt crystallization and separation a concentrate from a concentrator when the concentrator maintains the salt solutions at below salt saturation, wherein the process order is (i) concentrator, (ii) crystallizer, (iii) separator.
  • Another aspect of the disclosure is a process of purifying a feed stream containing water, comprising: providing a feed stream to at least one crystallizer to provide a concentrated output stream; directing at least a first portion of the concentrator output stream to a crystallizer which outputs a saturated solution and Page 5 of 56 232614 salt crystals; and directing a second portion of the concentrator output stream to a separator; directing a third portion of the concentrator output stream to a seepage tank to form seepage; directing the seepage to the input stream; directing at least a first portion from the concentrator to a permeate vessel to form a permeate; directing at least a second portion of the condensed concentrated output through a filter to provide a filter cake and a permeate; directing at least a portion of the permeate to the feed stream; wherein at least a portion of the filter cake comprises salt crystals.
  • VMD includes three stages based on temperature: A) the hot feed water circulation stage; B) the produced vapor stage and C) the cooling stage.
  • the feed circulation water can operate within the range of about 35°C to about 75°C, or about 40°C to 70°C, or about 45°C to about 65°C.
  • the feed water circulates in a loop starting from feed water tank and then into the membrane modules where it is partially concentrated by losing pure water as vapor.
  • the produced vapor temperature is usually about 1°C to about 10°C, or about 2 °C to about 9 °C, or about 3 °C to about 8 °C, or about 4°C to about 7°C or about 5°C or about 6°C, lower than feed water temperature.
  • the produced vapor may have a temperature that is higher than the feed water temperature by as much as 50°C, or 40 °C, or 30 °C, or 30 °C or 15 °C, or higher, or other values in between. A greater temperature drop leads to a higher produced flux.
  • the cold/cooler portion of VMD includes the condensers where produced vapor condensed into near pure water.
  • membrane modules work in a low pressure which is limited to a total water entry pressure (WEP) of about 15-30 psi, 17-27 psi, 20-25 psi, or about 24psi depending on the hydrophobic membrane used.
  • WEP total water entry pressure
  • the water pressure inside a Page 6 of 56 232614 membrane module is limited to less than about 10 psi.
  • VMD can have one or more membrane modules, where each membrane module has a membrane bundle having a hollow fiber membrane with a surface area of about 1 to about 20 m 2 , such as about 5 to 15 m 2 or about 7 to 13 m 2 or about 10m 2 .
  • a membrane module operates usually in an inside-out mode of operation wherein liquid goes inside the lumens of fibers while the vapor is produced in the shell and is collected through vapor collectors which are connected to vapor condensers.
  • the opposite configuration is also possible. Alternate configurations can also be used: such as a flat sheet or spiral wound.
  • the vapor condensers may be shell-and-tube heat exchangers or plate-and-frame heat exchangers operating via a cooling liquid, cooled by a chiller, which is circulated within the cooling loop, inside the tube, or opposite side of the plate, to adsorb the heat and condense the vapor, inside the shell. Vapor can alternatively be on the tube side.
  • the system includes a seepage vessel.
  • Each membrane module can produce some seepage which is collected into the seepage vessel; although some of the seepage may be condensed vapor inside the shell at early time of operation before modules being warmed.
  • This vessel is equipped with level detectors directing a seepage pump to collect seepage and return it to the feed tank, permeate tank or alternative processing tank.
  • the distillation system includes a permeate vessel where the VMD-produced vapor, after being condensed into liquid water, is collected.
  • the vessel may be equipped with Page 7 of 56 232614 level indicators and controls.
  • This permeate is a very high-quality water, that is, salts substantially fully separated out, and when required, the permeate will be pumped to the permeate storage tanks.
  • a vacuum pump is used to establish the desired vacuum level.
  • the vacuum pump is designed to produce the vacuum at the beginning and during the process.
  • a heat exchanger is used to heat the feed water to desired temperature for example in the range of about 40 °C to about 75°C, and other ranges disclosed elsewhere herein.
  • the source of heat can be different from renewable energy sources to available waste energy, electricity, as well as legacy energy sources.
  • the VMD process can be integrated with energy recovery units such as a heat pump (HP) and mechanical vapor compression (VMC).
  • the VMD system may include at least two feed tanks where one will be in operation and will, in a first tank, concentrate until near saturation of the least soluble salt. The nearly saturated solution from the feed tank with saturated salt solution will be sent to a crystallization tank where it will be cooled down to speed up crystallization where it is possible. The first VMD feed tank will then be filled with a fresh batch of the same feed.
  • HP heat pump
  • VMC mechanical vapor compression
  • the supernatant of the crystallization tank with microcrystals will be sent to ultrafiltration (UF) where smaller crystals will be separated in the UF concentrate while UF permeate will be sent to the feed tank after it is heated to a desired temperature (depending on the solubility of remaining salts) with, for example, a heat exchanger.
  • the UF concentrate will be sent back to the crystallization tank.
  • the solid crystals will be sent to a solid handling process such a filter press.
  • the UF filtrate (permeate) will be sent to the VMD feed tank. Page 8 of 56 232614 [0033]
  • the solution in the feed tank reaches a desired concentration, the solution will be sent to the crystallization tank.
  • the temperature of this tank will be independent of that of the concentrator and controlled at a temperature to promote crystallization.
  • the VMD-ICR system can also be designed without a crystallization tank meaning the size of the crystals and their separation will be managed within the feed tank and a separation unit such as reverse osmosis, ultrafiltration or other filtration system (microfiltration, nanofiltration, hydrocyclone).
  • ultrafiltration may be used as a separator.
  • the separator for example UF molecular cutoff (about 50,000 daltons, about 100,000 daltons, about 150,000 daltons, about 200,000 daltons or about 250,000 daltons) is chosen to be very tight to let only dissolved solids and macromolecules pass through so that all particulates including microcrystals will be separated.
  • the UF membrane could be ceramic or organic materials. Ceramic membranes can be used at high pressures and temperatures (such as 80, 90, 100°C) while organic membranes such as paper, cellulose acetate, PVDF, polysulfide, PTFE, and polymeric membranes are more useful in the range of 10-40°C (PS, PVDF, PTFE membranes can stand to about 70°C ).
  • the UF system is equipped with a clean in place (CIP) system for cleaning of the UF membrane when it is required.
  • CIP clean in place
  • a salt concentrator operates at or above saturation where the process flow is from concentration/VMD to crystallization to separation.
  • a mode of operation is similar to the operation mode where VMD operates below saturation. VMD produces crystals beyond saturation which can be removed by a separation process such as UF prior to entering the crystallization tank.
  • a sample at Page 9 of 56 232614 or above saturation can also be run in the order concentration, separation, then crystallization.
  • a salt crystallization and separation system comprising (i) a concentrator; (ii) a crystallizer and (iii) a separator.
  • the concentrator comprises: at least one VMD module; at least one VMD feed tank; a heat source; a vacuum source and a cooling source; circulation pumps; heat exchangers, for heating the feed and condensing the vapor.
  • the crystallizer comprises a process tank comprising at least one temperature control mechanism; a crystal recovery system such as filter press; transfer pumps; the separator comprises at least one filtration component selected from microfiltration, ultrafiltration, nanofiltration, and a filtrate tank.
  • the disclosure provides a process of separating at least one salt from a liquid stream comprising the at least one salt, the process comprising: providing a liquid stream comprising the at least one salt; concentrating the liquid stream to at least near saturation; crystallizing the at least one salt out of the liquid stream to produce a slurry comprising crystals of the at least one salt; and separating the salt crystals from the salt slurry.
  • concentrating the liquid feed stream comprises treating the liquid stream with vacuum membrane distillation.
  • crystallizing the at least one salt comprises adjusting the temperature of the liquid stream and/or of the crystallizer until at least a portion of a least soluble salt precipitates out of solution.
  • separating salt crystals from the salt slurry comprises at least one selected from coarse filtration, hydrocyclone filtration, ultrafiltration, microfiltration and nanofiltration.
  • the at least one hydrophobic porous membrane is used for vacuum membrane distillation.
  • the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 Page 10 of 56 232614 m 2 , or about 1 to about 20 m 2 , preferably about 5 to 15 m 2 , more preferably about 7 to 13 m 2 and still more preferably about 10m 2 .
  • the hydrophobic porous membrane has a pore size of less than 0.5 micron, preferably about 0.05 micron to about 0.45 micron, preferably about 0.2 micron to about 0.45 micron, preferably about 0.25 micron to about 0.45 micron.
  • near saturation is defined as at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, at least 99.5%, or at least 99.9% of the saturation concentration of at least one salt, or other values in between the foregoing.
  • near saturation is defined as a concentration greater than the saturation concentration obtainable by the crystallizer.
  • the invention provides a process of purifying a feed stream containing water, comprising: providing a feed stream to at least one crystallizer to provide a more concentrated output stream; directing at least a first portion of the concentrator output stream to a crystallizer which will output saturation solution and salt crystals; directing a second portion of the concentrator output stream to a separator; directing a third portion of the concentrator output stream to a seepage tank to form seepage; directing the seepage to the input stream; directing at least a first portion from the concentrator to a permeate vessel to form a permeate; directing at least a second portion of the condensed concentrated output through a filter to provide a filter cake and a permeate; directing at least a portion of the permeate to the feed stream; and wherein at least a portion of the filter cake comprises salt crystals.
  • the invention provides: a system for removing salts from a liquid stream, comprising: a concentrator configured to concentrate at least one salt to at least near the saturation point of the at least one salt; a crystallizer configured to crystallize at least one salt; and, a separator configured to separate crystals of the at least one salt from the liquid stream.
  • the concentrator comprises: a vacuum membrane distillation unit comprising at least one porous hollow fiber membrane.
  • the Page 11 of 56 232614 the crystallizer comprises: at least one condenser.
  • the separator comprises: at least one selected from a coarse filtration unit, a hydrocyclone filtration unit, an ultrafiltration unit, a microfiltration unit and a nanofiltration unit.
  • the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 m 2 , or about 1 to about 20 m 2 , preferably about 5 to 15 m 2 , more preferably about 7 to 13 m 2 and still more preferably about 10m 2 .
  • the at least one porous hollow fiber membrane has an average pore diameter of 0.5 micron, preferably about 0.05 micron to about 0.45 micron, more preferably about 0.2 micron to about 0.45 micron, and still more preferably about 0.25 micron to about 0.45 micron.
  • the at least one condenser comprises or is selected from: shell-and-tube heat exchanger, plate-and-frame heat exchanger, and a chiller including a cooling loop.
  • the system is configured to operate in an inside-out mode of operation wherein a liquid feed stream enters lumens of hollow fibers while a vapor is produced in a shell and is collected through vapor collectors which are connected to vapor condensers.
  • the system further comprises at least one of a seepage vessel and a permeate vessel.
  • the separator has a molecular cutoff of about 1 to about 250,000 daltons, for example, about 50,000 daltons, about 100,000 daltons, about 150,000 daltons, about 200,000 daltons or about 250,000 daltons or ranges between the foregoing values or values within the foregoing ranges..
  • FIG.1 depicts a simplified overview of process flow of an embodiment of the disclosure. Page 12 of 56 232614
  • Figure 2 depicts an exemplary process flow of the disclosure.
  • Figure 3 depicts an exemplary process flow of the disclosure.
  • Figure 4 depicts an exemplary process flow of the disclosure.
  • Figure 4A depicts a portion of an exemplary process flow of the disclosure as shown in FIG.4.
  • Figure 5 is a longitudinal cross-section of a membrane distillation module of an embodiment of the disclosure.
  • Figure 5A is a detailed view of an embodiment of Figure 5.
  • Figure 5B is a detailed view of an embodiment of Figure 5.
  • Figure 6 is an exploded view of an embodiment of Figure 5.
  • Figure 7 depicts a relation between concentration and temperature for selected salts.
  • Figure 8 (FIG.8) is a schematic overview of an exemplary separation process flow.
  • Figure 9 depicts an example of the process flow of Figure 8.
  • Figure 10 depicts mass balance results of an exemplary process flow of Figure 8.
  • Figure 11 depicts the feed flow composition for the process of Figure 8.
  • Figure 12 depicts estimated energy consumption of an embodiment of the disclosure.
  • Figure 13A depicts actual precipitate and composition quantities of an embodiment of the disclosure.
  • Figure 13B (FIG.13B) precipitate proportions and overall salts removed of an embodiment of the disclosure.
  • Figure 13C (FIG.13C) depicts actual precipitate and composition quantities of an embodiment of the disclosure.
  • Figure 13D depicts estimated results of six rounds of room temperature precipitation of an embodiment of the disclosure.
  • Figure 13E depicts estimated results of room temperature precipitation of an embodiment of the disclosure.
  • Figure 13F depicts actual measurements of salts in supernatant from six batches of separated salts. Page 13 of 56 232614
  • Figure 14 depicts quality and quantity of water removed during six rounds of separation.
  • Figures 15A-15J depict potassium chloride removal in various embodiments of the disclosure.
  • Figure 16 depicts a ternary phase diagram of two salts and water.
  • Figure 17 depicts a graphical relation between solubility and temperature of four salts.
  • Figure 18 is a graphical depiction of a relation of solids by mass vs. permeate volume for an embodiment of the disclosure.
  • Figure 19 shows the data for Figure 18.
  • Figure 20 (FIG.20) is a graphical depiction of a relation of solids by mass vs. permeate volume for three fractions of an embodiment of the disclosure.
  • Figure 21 (FIG.21) shows the data for Figure 20.
  • Figure 22 depicts a salt analysis of crystals obtained at the vacuum membrane distillation stage of an embodiment of the disclosure.
  • Figure 23 depicts a relation of solids by mass vs. permeate volume with a smoothed total precipitate curve of an embodiment of the disclosure.
  • Figure 24 shows the data for Figure 23.
  • Figure 25 depicts a relation of solids by mass vs. permeate volume with total precipitate produced at +22°C of an embodiment of the disclosure.
  • Figure 26 (FIG.26) shows the relation between precipitate mass produced in each round of precipitation vs. permeate volume of an embodiment of the disclosure.
  • Figure 27 shows the data for Figure 26.
  • Figure 28 (FIG.28) is a schematic overview of an exemplary separation process flow.
  • Figure 29A (FIG.29A) shows a pilot unit feed composition and concentrations after one step of vacuum membrane distillation of the embodiment of Figure 28.
  • Figure 29B (FIG.29B) depicts initial concentration of lab unit feed water of the embodiment of Figure 28. Page 14 of 56 232614
  • Figure 30 (FIG.30) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 31 (FIG.31) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 32 depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 33 depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 34 depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 35 depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure.
  • Figure 36 (FIG.36) provides an overview of initial feed and final processed salt quantities and TDS in an embodiment of the disclosure.
  • FIG.37 shows the total water removed in an embodiment of the disclosure.
  • Figure 38 (FIG.38) depicts mass and percentage of salts removed from 26 rounds of processing of an embodiment of the disclosure.
  • Similar numbers refer to similar parts throughout the drawings.
  • the drawings illustrate, and do not limit, the scope of this disclosure.
  • VMD-ICR vacuum membrane distillation-integrated crystallization reactor
  • the vacuum membrane distillation-integrated crystallization reactor is designed to concentrate brine streams beyond the point of individual salt saturation levels by adjusting the operation conditions, particularly temperature and flow conditions. Under these conditions initially micro crystals and gradually macro crystals will form that can be separated sequentially from low solubility to high solubility.
  • Suitable techniques for separation of fine crystals include microfiltration (MF) ultrafiltration (UF), nanofiltration (NF) or any separation technology that can effectively separate the produced micro/macro crystals.
  • a foundational step of the disclosure is the production and separation of pure micro crystals in the VMD-ICR. This can be achieved by the combination of three different unit operations: VMD, crystallization and separation as shown in FIGS.2 and 3.
  • the precipitants are recovered as a series of solids, high purity water is produced, and a concentrate of the most soluble salt is produced (if the process is not run to completion a mixture of the most soluble salts will be produced).
  • the three unit operations are a concentrator, a crystallizer and a separator.
  • VMD-ICR process 1 includes a three-stage system and process 2, which includes concentrator 2a (concentration), which produces concentrate 2b, Page 16 of 56 232614 flowing into crystallizer 2c (crystallization), which produces a slurry 2d of concentrated salts and water leading into separator 2e (separation). Feed flow 3 containing at least one salt is feeds into concentrator 2a to start the process.
  • At least one salt is crystallized/precipitated out of the concentrated feed to form a slurry 2d.
  • Concentrator 2a also produces purified water 7.
  • Slurry 2d is transferred to separator 2e, which physically separates salt crystals from a saturated solution of the nth salt. Separator 2e provides precipitants 1, 2, 3 through precipitant n-1 (indicated by reference numeral 4) and a saturated solution of the nth salt (indicated by reference numeral 5). An ever more concentrated solution from separator 8 is recycled (indicated by reference numeral 6) back to concentrator 2a.
  • the disclosure provides a more detailed process flow 10.
  • process 10 includes concentration process 20, crystallization process 30 and separation process 40.
  • brine feed 90 is fed to VMD process tanks 100, 102 and 104. It will be appreciated that there can be any number of VMD process tanks. VMD process tanks 100, 102 and 104 act as settling tanks, and hold a supply of brine feed prior to entering VMD unit 118.
  • Valves 100a, 100b, 102a, 102b, and 104a when properly configured may allow settled solids to flow out of VMD process tanks 100, 102 and 104 which are moved by transfer pump 105 to filtration membrane 144, which may be a ceramic or organic membrane and may be classified as ultrafiltration, microfiltration, nanofiltration or other filtration types.
  • the brine feed 90 may be heated in VMD process tanks 100, 102 and 104 using heated water provided by heat exchanger 114 which receives heated water from heater 112. Heated water is provided to VMD process tanks 100, 102 and 104 by proper operation of valves 114a and 114b.
  • Heat may also be provided to VMD process tanks 100, 102 and 104 by proper operation of valve 110b, which directs heated water from heat exchanger 110 which also received heated water from heater 112.
  • the foregoing processes are driven by process pump 106 and reheating pump 108.
  • process pump 106 moves effluent from VMD process tanks 100, 102 and 104 through process heat exchanger 116 to VMD unit 118.
  • VMD unit 118 has three outputs: (i) Page 17 of 56 232614 vapor which becomes condensate in main condenser 124, (which itself is maintained at cooler than ambient temperature by cooling source 126).
  • VMD unit 118 also outputs seepage to seepage vessel 120.
  • Seepage is an accumulation of liquids on the vapor side (low pressure side) of the VMD membrane system. Seepage through the hollow fiber membrane within VMD module 118 is also possible. Seepage is also possible due to imperfections in the VMD unit, such as leaky seals. Seepage is returned to VMD process tanks 100, 102 and 104 by proper operation of valves 120a, 122a and seepage pump 122. VMD unit 118 also recycles a portion of its input back to VMD process tanks 100, 102 and 104. [0107] Flow through VMD module 118 and permeate vessel 128 is driven by vacuum pump 132, with pulls a vacuum therethrough. The vacuum pulled on VMD module 118 is through seepage vessel 120.
  • Seepage not pulled out of seepage vessel 120 is moved by seepage pump 122 and proper operation of valve 120a where it is returned to at least one of VMD process tanks 100, 102 and 104.
  • Permeate vessel 128 outputs pure water through action of pump 130 and proper operation of valve 128a.
  • the flow traverses filtration membrane 144 and then by proper operation of valve 144a, enters crystallization tanks 160 and 162, which is the first step in crystallization process 30.
  • Flow passing through filtration membrane 144 may also pass through clean-in-place (CIP) loop 146 by proper operation of valves 146a and 146b.
  • CIP clean-in-place
  • CIP loop 146 washes the process water with dilute acid (acetic, hydrochloric, phosphoric or others) to dissolve any accumulated salts that have not been eliminated by filtration membrane 144.
  • dilute acid acetic, hydrochloric, phosphoric or others
  • feed flow passing through filtration membrane 144 either goes through CIP loop 146 or into filtration permeate tank 140, which, by proper operation of valve 140a and pump 142, is recycled through heat exchanger 114 and valves 114a, 114b to VMD process tanks 100, 102 and 104.
  • crystallization tanks 160 and 162 each contain a cooling loop 163a and 163b, respectively. Cooling water is generated by chiller 126.
  • FIG.3 depicts process 310 including concentration process 320, crystallization process 330 and separation process 340.
  • brine feed 390 is fed to VMD process tanks 400 and 402. It will be appreciated that there can be any number of VMD process tanks.
  • VMD process tanks 400 and 402 act as settling tanks, and hold a supply of brine feed prior to entering VMD unit 418.
  • Valves 400a, 400b, 400c, 402a, and 402b, when properly configured may allow settled solids to flow out of VMD process tanks 400 and 402 which are moved by transfer pump 408 to crystallization tanks 440 and 442, which is the first step in crystallization process 330.
  • VMD process tanks 400 and 402 are heated from heated water provided by heat exchanger 414 which receives heated water from heater 412. Heated water is provided to VMD process tanks 400 and 402 by proper operation of valves 410a, 412a and 414a. [0114] The foregoing processes are driven by process pump 406 and reheating pump 404. By proper operation of valves 400a, 400b, 400c, 400d, 400e, 402a, and 422a, process pump 406 moves effluent from VMD process tanks 400 and 402 through process heat exchanger 416 to VMD unit 418.
  • VMD unit 418 has three outputs: (i) vapor which becomes condensate in main condenser 424, (which itself is maintained at cooler than produced vapor temperature by cooling source 426). VMD unit 418 also outputs seepage to seepage vessel 420. Seepage is an accumulation of liquids on the vapor side (low pressure side) of the VMD membrane system. Seepage through the hollow fiber membrane within VMD module 418 is also possible. Seepage is also possible due to imperfections in the VMD unit, such as leaky seals. Seepage is returned to VMD process tanks 400 and 402 by proper Page 19 of 56 232614 operation of valves 420a and 422a and seepage pump 422. VMD unit 418 also recycles a portion of its input back to VMD process tanks 400 and 402.
  • Vapor flow through VMD module 418 and permeate vessel 428 is driven by vacuum pump 432, which pulls a vacuum therethrough.
  • the vacuum pulled on VMD module 418 is through seepage vessel 420. Seepage not pulled out of seepage vessel 420 is moved by seepage pump 422 and proper operation of valve 420a where it is returned to at least one of VMD process tanks 400 and 402.
  • Permeate vessel 428 outputs pure water through action of permeate pump 430 and proper operation of valve 428a.
  • the flow traverses valve 408a into crystallization tanks 440 and 442, which is the first step in crystallization process 30.
  • Crystallization tanks 440 and 442 each contain a cooling loop 443a and 443b, respectively. Cooling water is generated by chiller 426. As the temperature of the contents of crystallization tanks 440 and 442 cool, salts begin to precipitate out of solution. [0117] Such salts are concentrated, in some cases to the point of supersaturation, and pulled out of crystallization tanks 440 and 442 by crystallizer pump 450 and passed through a filter, such as filter press 474 through proper operation of valves 440a, 440b, 440c, 442a and 442b. The filter cake is high purity salt crystals, while the permeate is returned to the VMD process tanks 400 and 402 by UF permeate pump 462.
  • crystallizer pump 450 From crystallizer pump 450, by proper operation of valves 450a and 474a, a portion of the flow is directed to filtration membrane 464. Flow passing through filtration membrane 454 may also pass through clean-in-place (CIP) loop 466 by proper operation of valves 466a and 466b. CIP loop 466 washes the process water with dilute acid (acetic, hydrochloric, phosphoric or others) to dissolve any accumulated salts that have not been eliminated by filtration membrane 464. [0119] Returning to the discussion of the first steps in crystallization process 30, crystallization tanks 440 and 442 each contain a cooling loop 443a and 443b, respectively. Cooling water is generated by chiller 426.
  • CIP clean-in-place
  • Process Round 1, 710 begins with a liquid feed stream 705 entering VMD concentration step #1 710a, which produces supersaturate #1 710b, which is transferred to crystallization step #1 710c, producing slurry #1 710d, which is separated in separation step #1710e to afford salt crystals #1710f.
  • a concentrate #1710g is recycled from separation #1710e to form the feed for VMD concentration step #2720, the start of process round #2.
  • process round #2 (720) and process round #3 (730) proceed exactly as process round #1, with analogous steps similarly numbered and with the concentrate #2730g moving to VMD concentration step #3.
  • process round 2 (720) and/or process round #3 (730) proceed differently from process round #1 (710) in terms of at least one of VMD flow and/or operating pressure; crystallization temperature or separation conditions.
  • each VMD concentration step involves at least one vacuum membrane distillation unit comprising at least one porous hollow fiber membrane.
  • each crystallization step involves at least one heat exchanger and/or cooling unit.
  • each separation step involves at least one of reverse osmosis, coarse filtration, hydrocyclone filtration, ultrafiltration, microfiltration and nanofiltration.
  • VMD concentration step #1710a also produces permeate 710'
  • VMD concentration step #2 also produces permeate #2720'
  • VMD concentration step #3 also produces permeate #3730'.
  • Advancing to the end of VMD concentration step #3, specifically crystals #3 are advanced to recrystallization #1730h, which is expanded in FIG.4A.
  • FIG.4A depicts crystals #1730f entering hot recrystallization #3730h. Pure water 730f' also enters the recrystallization here.
  • Hot recrystallization #3730h produces a hot recrystallization filtrate 730i and recrystallization crystals #3H 730l.
  • Hot recrystallization filtrate 730i flows to cold recrystallization #3730j, which produces cold recrystallization filtrate 730k and cold recrystallization crystals #3F 730m.
  • H indicates a hot recrystallization step or its result
  • F indicates a cold (“freezing") recrystallization step or its result
  • RT indicates a room temperature recrystallization step or its result.
  • Process Round 3 at separation #3 recycles concentrate #3 to feed Process Round #4, VMD concentration step #4740a, which produces supersaturate 740b, which is transferred to crystallization step #4-RT 740c, producing slurry #4 740d, which is separated in separation step #4-1740e to afford salt crystals #4-RT 740f.
  • separation step #4-1 740e a filtered supersaturate #4 is fed to crystallization #4F 740h, producing slurry #4F, which is separated in separation step #4-2740j into crystals #4F 740j and concentrate #4740k, which is recycled into VMD concentration step #5750a.
  • process round #5750 and process round #6760 proceed exactly as process round #4740, with analogous steps similarly numbered and with the concentrate #5750k moving to Process round 760, VMD concentration step #6.
  • VMD concentration step #4740a also produces permeate 740'
  • VMD concentration step #5 also produces permeate #4750'
  • VMD concentration step #6 also produces permeate #6760'.
  • FIG.5 depicts a longitudinal cross-section of a membrane distillation module 10 (HFDM - Hollow Fiber Distillation Module or just "Module") showing module shell 12, fiber membrane bundle 22 with module top cap 18, and module bottom cap 20.
  • Module 10 is suitable for receiving the fiber membrane bundle 22 of the present disclosure.
  • the module includes a housing comprising a module shell 12 having a module top flange 14 and a module bottom flange 16 at top and bottom ends, respectively, of module shell 12.
  • Each flange may be manufactured from an engineered plastic and is connected to the module shell 12 via a chemical welding, fusing or gluing process.
  • FIG.5A is an expanded view of FIG.5 showing Detail 5A: the module top cap 18 and threads.
  • FIG.5B is an expanded view of FIG.5 showing Detail 5B: the module bottom cap 20 and threads 33.
  • FIG.5A is an expanded view of Detail 5A of FIG.5 showing the shell 12, with flange 14; threads 33 on the outer diameter of a center core 32; and threads 35 on the inner diameter of module top cap 18.
  • Center core 32 may have various cross sections such as triangular, square, pentagonal, ellipsoidal, or circular. It is preferred that center core 32 has a circular cross section, making center core 32 a cylinder.
  • Page 22 of 56 232614 Upper boot flange 48 supports module top cap 18 which is threadedly engaged therewith.
  • Spacer ring 54a surrounds upper membrane boot 44.
  • FIG.5B is an expanded view of Detail 5B of FIG.5 showing the module bottom flange 16, threads 33 on the outer diameter of center core 32 as well as threads 35 on the inner diameter of bottom boot 46.
  • Threads 33 and 35 serve to increase the surface area of the outer diameter of center core 32 and the inner diameter of receiver 36 to improve engagement with the potting material 23, which in one embodiment may be epoxy or other thermoplastic materials, to provide a vacuum seal to prevent leakage.
  • the shell 12 is, in one embodiment, a single cylindrical tube made of a thermoplastic capable of withstanding operating temperatures varying from 5°C to 100°C. Shell 12 may alternatively comprise more than one component (not shown).
  • Module top flange 14 provides for connection to a corresponding flange on a vapor collector header (not shown). The connection between the flanges is accomplished via interconnecting bolts 58 as seen in FIG.6.
  • module bottom flange 16 provides for connection to module bottom cap 20.
  • the module bottom cap 20 receives fiber membrane bundle 22 and therefore serves as bottom cap of the membrane module.
  • the module bottom cap 20 may, in one embodiment, be manufactured from a single piece of thermoplastic.
  • module bottom cap 20 includes an industry standard 12” flange 24 having the same bolt pattern as the module bottom flange 16.
  • the bottom end incorporates the hydraulic connections to the cap including the feed water inlet 26, the concentrate water outlet 28, and a seepage outlet 30.
  • the feed water inlet 26 is fluidly connected to the center core 32 of the fiber membrane bundle 22.
  • the feed water inlet 26 is in one embodiment a standard 2” male “Camlock” connection type.
  • a series of seals ensures the hydraulic integrity at the interface point of the module bottom Page 23 of 56 232614 cap 20 with the ends 32a and 32b of center core 32 of the fiber membrane bundle 22.
  • Liquid flowing out of the hollow fiber membranes 42 is collected in the module bottom cap 20 and directed to the concentrate outlet 28 of the connector, which in one embodiment is a 2” male “camlock” connection type.
  • a series of seals 40b, 40c, 40d ensures the hydraulic integrity at the interface point of the fiber membrane bundle 22 with the module bottom cap 20 and concentrate outlet 28.
  • the seepage outlet 30 is at the module bottom cap 20 of the fiber membrane bundle 22. Any liquid that should pass through the membrane is collected and returned to a seepage tank (not shown) of the process via the seepage outlet 30, which in one embodiment is of the 1” male “camlock” connection type.
  • Male “camlock” connections for feed water, concentrate and seepage correspond to female “camlock” connections which are typically by braided hose or rubber hose but may also be a hard-piped connection.
  • the module bottom cap 20 comprises a receiver 36 for a fiber membrane bundle 22 having, one embodiment, an approximate diameter of 8”.
  • the receiver 36 is designed to accommodate complete vacuum.
  • Receiver 36 is at the center of the module bottom cap 20, and is, in one embodiment, a female connection region for the fiber bundle 20 which is approximately 150 mm in diameter.
  • Central to the receiver for the fiber bundle is an end core receiver 38 for receiving a center core end connector 34 of fiber membrane bundle 22.
  • receiver 36 is equipped with two “O” ring seals 40c and 40d around its inner circumference. Stated differently, O-rings 40c and 40d fit into chamfers on the outer diameter of center core connector 34.
  • FIG.6 is an exploded view of the hollow fiber membrane bundle of FIG.5 in which a plurality of hollow fiber membranes 42, depicted collectively as fiber membrane bundle 22, is disposed between top and bottom membrane boots 44, 46.
  • the ends 42a, 42b, of the hollow fiber membranes 42 are secured to the membrane boots 44, 46 by chemical bonding with a potting material 23.
  • Potting material 23 may Page 24 of 56 232614 be a thermoplastic polymer that is used to secure the ends of the plurality of hollow fiber membranes 42 to the membrane boots 44, 46.
  • Each membrane boot 44, 46 has a bundle flange 48 (top), 50 (bottom).
  • Bundle flanges 48, 50 fit "inboard" of the membrane boots 44, 46. That is, upper bundle flange 48 fits to the bottom end of upper membrane boot 44, while lower bundle flange 50 fits to the top end of lower membrane boot 46.
  • supporting rods 52 are secured at each end to the respective bundle flanges 48, 50 and provide structural support to (that is, they act to provide longitudinal tension to) the fiber membrane bundle 22.
  • each of the bundle flanges 48, 50 comprises two halves, for ease of assembly.
  • bundle flanges 48, 50 include two concentric rings of apertures 48a and 50a, to accommodate two sets of bolts (generally 58) for two different purposes.
  • the inner ring of apertures 48a defined in bundle flange 48 accommodates bolts 58a to attach bundle flange 48 "up" to upper membrane boot 44.
  • the outer ring of apertures 48b defined in bundle flange 48 accommodates a different set of bolts 58b to attach bundle flange 50 "down" to supporting rods 52.
  • Center core 32 best seen in Figures 5, 5B, runs up the center of the fiber membrane bundle 22.
  • a center core connector 34 provides a fluid connection for feed water to enter center core 32 from the feed water inlet 26 of the module bottom cap 20.
  • a module top cap 18 is sealingly attached to the top membrane boot 44.
  • Center core 32 transmits feed water from inlet 26 of module bottom cap 20 to the module top cap 18 where it is distributed to the hollow fiber membranes 42 for return flow down the interior (lumen) (not shown) of the hollow fiber membranes 42.
  • the feed water may be provided to the exterior of the hollow fiber membranes 42.
  • a spacer ring 54a disposed between the top bundle flange 48 and the module top cap 18 assists with engagement and sealing of module top cap 18.
  • the inner surface of the spacer ring has a chamfer 39 at one edge to seat an O-ring 40a.
  • Another spacer ring 54b assists engagement and sealing of the bottom membrane boot 46 with the module bottom cap 20, as seen in FIG.4.
  • Projections 56 extending radially from the module top cap 18 are dimensioned to approach or abut the inner circumference of the module shell 12, thereby locating and supporting the membrane element in proper axial orientation and protecting the Page 25 of 56 232614 fiber membrane bundle 22 from malfunction or damage resulting from lateral movement within the shell 12.
  • Flow of vapor around the membrane fibers 42 is influenced by the packing density of the fibers.
  • the packing density of the fiber membrane bundle 22 is engineered for optimal performance for the intended application.
  • the effective membrane length LE is the length of a fiber bundle, between top membrane boot 44 and bottom membrane boot 46, which contributes to vapor production.
  • Total membrane bundle length, LT refers to the total length of a membrane bundle, including LE, the length of module bottom cap 20 including, in one embodiment, bundle inlet camlock connector 26, plus the length (LP) of two membrane boots 44, 46.
  • the distance LE is about 70 cm, and may be about 80 cm, about 90 cm, about 100 cm about 110 cm, 120 cm or other values in between.
  • the length LP is about 5 cm, about 10 cm, about 15, cm, about 20 cm, about 25 cm or other values in between.
  • the feed solution is a solution containing a series of salts.
  • Each salt has an individual solubility, but the entire matrix of salts and the interactions of salts define the saturation point of the entire solution.
  • the system can be run, but is not limited to, in the following manners: using solubilities determined by experimentation, estimation, thermodynamics or trial and error.
  • the Page 26 of 56 232614 mixture solubility can be estimated by using the solubility of the components in the mixture. Each component generally precipitates earlier than its individual solubility limit would suggest.
  • C sat,mix Saturation Concentration of the mixture of dissolved solids [0147]
  • C sat,n Saturation Concentration of the individual dissolved solid [0148]
  • x n the mass fraction of the individual dissolved solid [0149]
  • m n the experimentally determined constant or function [0150]
  • C Cation [0151]
  • c i cation’s stoichiometric factor [0152]
  • A Anion [0153]
  • a i Anion’s stoichiometric factor [0154]
  • (s) Chemical Sate: Solid [0155]
  • (aq) Chemical State: Aqueous [0156]
  • K i Equilibrium Constant for individual species [0157] Thermodynamics gives a rigorous process to determine the solubilities using the equations of state and equilibrium chemistry simultaneously.
  • Process Des VMD is a semi-batch unit consisting of a single ne area).
  • the concentrated solution is then removed from the feed tank, and the system is flushed with water to remove any residual salts prior to starting a new batch.
  • the membrane is flushed with a dilute acid solution, such as citric acid, to remove any deposits. Excessive seepage is typically associated with organic material in the feed.
  • the concentrate, once removed from the feed tank is allowed to cool to room temperature at which point the low solubility salts precipitate out of solution. In the commercial system, precipitated salts will be recovered “in line” via a cooling loop and inline filtration.
  • VMD vacuum membrane distillation
  • Step 1 806, of vacuum membrane distillation (VMD) concentrates the feed sample to remove 70% of water resulting in NaCl removal, 808.
  • Step 2 of VMD is further concentration, 810, which removes a total of 95% of water resulting in KCl recovery, 812, followed by recovery of LiCl and MgCl 2 , step Page 34 of 56 232614 816.
  • the two concentration steps 806 and 810 result in 95% water recovery, 814, with less than 10 ppm total dissolved solids (TDS) remaining.
  • the 200 liters of feed sample 901 is split into four VMD feed batch tanks (902, 904, 906, and 908) each having a capacity of only 50 liters.
  • Each 50 liter feed sample then flows into a respective VMD unit (912, 914, 916, and 918). Processing in each of the four VMD units results in recovered water 920 and concentrates 1-4 (922, 924, 926, 928), which all feed into tank 930 resulting in precipitated salt.
  • Concentrates 1 and 2 (922, 924) are fed into a fifth VMD unit 933 to produce concentrate 5, 943, while concentrates 3 and 4 (926, 928) are fed into a sixth VMD unit 937, to produce a second quantity of recovered water 940 and concentrate 6, 947. Concentrates 5 and 6 are collected together to produce a final precipitated salt 950. [0173] Referring to FIG.10, the results of the six batch precipitation steps are shown schematically. Concentration takes place in VMD units 912, 914, 916, 918, 933 and 937 at 60°C. However other temperatures such as 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C or 90°C are possible.
  • a ternary phase diagram among NaCl, KCl and water there are 4 distinct regions on the phase diagram: the liquid region, (upper portion which includes the H 2 O corner) where all the salts are dissolved; the liquid + KCl(s) region (left side shaded portion), where there is a mixture of precipitated potassium chloride and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride.
  • Another region is the Liquid + NaCl(s) Region (right side shaded portion) where there is a mixture of precipitated sodium chloride and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride, and the last region the liquid + Fm3m + KCl(s) region (lower unshaded portion) where there is a mixture of precipitated potassium chloride, precipitated Fm3m and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride.
  • Fm3m is a cubic salt in which sodium, potassium and chloride form a mixed matrix salt. The situation for this mixture is more complicated as it contains significant amounts of lithium and magnesium, and an array of other salts in smaller amounts.
  • Figure 17 depicts the relation between solubility and temperature for the major components of the disclosed samples being separated. At elevated temperatures the solubility order from low to high is sodium chloride, potassium chloride, magnesium chloride then lithium chloride. This is the order in which the salts are expected to precipitate as water is removed. The slope of the solubility curves allows the choice of operating conditions which make producing a Page 37 of 56 232614 supersaturated solution in the VMD relative to the crystallization operating conditions.
  • the produced slurry is super saturated and allows the removal Page 38 of 56 232614 of salt based on the difference of mass contained in the slurry and the TDS of the concentrate at each stage relative to the saturation value at the precipitation conditions.
  • the precipitation took place in 5-gallon buckets first left to cool to room temperature and then moved to a chest freezer. Better temperature control and selectivity would be beneficial to the precipitation process.
  • the precipitates were recovered using a simple decanting followed by coarse filtration - 3 micron paper filter in a Buchner funnel. Some of the crystals were smaller than this size cut off and were believed to have been returned to a subsequent VMD concentration stage. The crystals at each stage were analysed for composition, the results are shown in FIG.
  • FIG. 27 shows the beginning of the chromatographic like separation of salts using the VMD- crystallization process.
  • VMD there are three stages based on temperature: A) the hot feed water circulation stage; B) the produced vapor stage and C) the vapor condensation stage at a temperature less than the vapor production stage.
  • the VMD units disclosed herein may be operated at selected temperatures, pressures and flow rates.
  • the VMD unit may be operated at 0-90°C, 10-80°C, 20-70°C, 30-60°C, 40-50°C, 50-70°C or 65-70°C.
  • the VMD unit may be operated at pressures such as 1-1000 mBar, 5-500 mBar, 10-200 mBar, or other values such as 70, 80, 90, 100, 110, 120, 130, 140, 150 mBar and other values between 1 and 1000 mBar. It is envisioned that a VMD unit of the disclosure may be operated as suitable flow rates in units of lmh (liters per square meter per hour) of 1-50, 2-40, 3-30, 4-20, or values such as 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19 lmh. [0199]
  • the feed circulation water can operate within the range of about 35°C to about 75°C, or about 40°C to 70°C, or about 45°C to about 65°C.
  • the feed water circulates in a loop starting from feed water tank and then it goes into the membrane modules where it is partially concentrated by losing pure water as vapor.
  • the produced vapor temperature is usually about 1°C to about 10°C, or about 2 °C to about 9 °C, or about 3 °C to about 8 °C, or about 4°C to about 7°C or Page 41 of 56 232614 about 5°C or about 6°C, lower than feed water temperature.
  • the cold/cooler portion of VMD includes the condensers where produced vapor condensed into near pure water.
  • membrane modules work in a low pressure which is limited to a total water entry pressure (WEP) of about 24 psi, more or less depending on the hydrophobic membrane used.
  • WEP total water entry pressure
  • the water pressure inside a membrane module is limited to less than about 10 psi.
  • VMD can have one or more membrane modules, each membrane module has a membrane bundle with hollow fiber membrane with a surface area of around, about 0.1 to 1 m 2 , 1 to about 20 m 2 , such as about 5 to 15 m 2 or about 7-13 m 2 or about 10m 2 .
  • the membrane module may operate in an inside-out mode of operation wherein liquid goes inside the lumens of fibers while the vapor is produced in the shell and is collected through vapor collectors which are connected to vapor condensers. The opposite configuration is also possible.
  • Condensers The vapor condensers usually are shell and tube heat exchangers operate via a cooling liquid (cooled by a chiller) which is circulated within the cooling loop inside the tube to adsorb the heat and condense the vapor inside the shell.
  • Seepage Vessel each membrane module can produce some seepage which is collected into the seepage vessel; although some of the seepage may be condensed vapor inside the shell soon after operation is begun and before modules are up to operating temperature. This vessel is equipped with level detectors and when required, the collected seepage is pumped back into the feed tank by the seepage pump.
  • Permeate vessel The VMD produced vapor, which, after being condensed and converted into liquid water, is collected inside the permeate vessel, Page 42 of 56 232614 which is equipped with level controls. This permeate is a very high-quality water and when required, will be pumped to the permeate storage tanks.
  • Vacuum a vacuum pump is used to establish the desired vacuum level. The vacuum pump is designed to produce the vacuum at the beginning of the process as well as to maintain the vacuum during the process.
  • Heating the heating heat exchanger is used to head the feed water to desired temperature for example in the range of about 40°C to about 75°C.
  • the source of heat can be different from renewable energy sources to available waste energy, electricity, as well as legacy energy sources.
  • VMD process can be integrated with energy recovery units such as heat pump (HP) and mechanical vapor compression (MVC).
  • HP heat pump
  • MVC mechanical vapor compression
  • the supernatant of the crystallization tank with micro crystals will be sent to ultrafiltration (UF) where small crystals will be separated in the UF concentrate while the UF retentate (permeate) will be sent to the feed tank after it is heated to a desired temperature (depending on the solubility of remaining salts) with a heat exchanger.
  • the UF concentrate will be sent back to the crystallization tank.
  • the solid crystals will be sent to a solid handling process such a filter press to remove excess liquid which may contain dissolved solids therein.
  • Crystallization Reactor When the solution in the feed tank reaches a desired concentration, the solution will be sent to the crystallization tank.
  • the temperature of this tank will be independent of the concentrator and controlled at a temperature to allow crystallization.
  • the VMD-ICR can also be designed without a crystallization tank meaning the size of the crystals and their separation will be managed within the feed Page 43 of 56 232614 tank and a separation unit such as UF or other filtration system (microfiltration, nanofiltration, hydrocyclone).
  • UF Ultrafiltration
  • the UF molecular cutoff (about 100,000 daltons, or in some cases up to about 250,000 daltons) is chosen to be very tight to let only dissolved solids and macromolecule to pass through and therefore all particulates including micro crystals will be separated.
  • the A separation unit with a molecular weight cut-off of 100,000 daltons should have a 90% rejection rate of dissolved materials with a molecular weight greater than 100,000 Daltons.
  • the UF membrane may include ceramic or organic materials. Ceramic membranes can be used at high pressures and temperatures (such as 80, 90, 100 °C) while organic membranes such as paper, cellulose acetate, PVDF, polysulfide, PTFE, and polymeric membranes are typically operated in the range of 10-40°C.
  • a process for salt crystallization and separation of a concentrate from a concentrator includes when the salt concentrator operates at or above saturation where the process flow is intake to concentration/VMD, to crystallization to separation.
  • An alternate mode of operation is similar to the operation mode where VMD operates below saturation. In this mode of operation VMD produces crystals beyond saturation which can be removed by a separation process like UF prior to entering the crystallization tank. Note that a sample at or above saturation can also be run in the order concentration, separation, then crystallization.
  • a process of concentrating and removing salts, in particular, lithium salts, from an input stream is set forth below.
  • the KMX pilot and laboratory scale VMD’s are semi-batch units, each consisting of a single membrane module.
  • the pilot unit is equipped with a third generation commercial sized module, while the lab unit has lab scale module of the same design.
  • feed is heated to 60°C before entering the membrane module.
  • the heated feed flows on the inside of the hollow fiber membrane fibers.
  • the water in the feed is converted to vapor Page 44 of 56 232614 which passes through the wall of the membrane and is condensed as “distilled water” (permeate).
  • the remaining “cooled” feed (concentrate) is returned to the feed tank for reheating and recirculation back to the membrane.
  • the process of recirculating the feed through the membrane and back to the feed tank continues until the desired water recovery level or salt concentration has been achieved. Each time the feed passes through the membrane, a percentage of the water is removed. Once the batch is complete, the concentrated solution is then removed from the feed tank, and the system is flushed with water to remove any residual salts prior to starting a new batch.
  • the concentrate, once removed from the feed tank is allowed to cool to room temperature at which point the low solubility salts precipitate out of solution. The remaining concentrate is put back in the VMD feed tank and the process repeated.
  • phase 2 A brine that was processed through reverse osmosis and was not the result of direct lithium extraction (non-DLE post RO) was processed at the KMX Technologies lab to concentrate and recover Lithium Chloride (LiCl) from the brine using KMX’s Vacuum Membrane Distillation (VMD) system.
  • the brine was composed of various salts, of which LiCl represented 4% by weight (a concentration of about 1,500 ppm) - see FIGS 28, 29A, and 29.
  • Phase 1 of the trial 81% of the water in the sample was removed (See Figure 29A, Table 11) and the brine was concentrated from about 46,000 to about 205,000 ppm, a concentration factor of about 4.8.
  • the LiCl in the sample was Page 45 of 56 232614 concentrated from about 1,500 ppm to about 11,800 ppm, the latter of which was the feed into the lab scale VMD. Because of contaminants in the sample (silica and surfactants), and their potential impact on membrane performance, it was decided at the end of Phase 1 to switch to a synthetic brine (free of contaminants) for Phase 2, such synthetic brine containing the same concentrations of the various salts obtained at the end of Phase 1.
  • a future trial may start with a larger volume which will allow greater concentration and removal of CaCl2 from the stream, leaving a higher purity level of LiCl.
  • An alternative to this would be to remove the CaCl2 before the reverse osmosis step. This would reduce the CaCl2 in the final concentrate, thereby increasing the purity level of the LiCl.
  • the process used to remove the non-Lithium salts was one of concentrating to the saturation point of each salt, followed by cooling and precipitation of the salt. Because of its relatively low solubility in the combined mixture, NaCl dropped out of solution first, followed by KCl.
  • a final concentration of 235,000 ppm LiCl was achieved over 26 rounds of precipitation, with 2-5 kgs of non- Lithium salts removed in each round. Some co-precipitation of salts also occurred during the process including LiCl. Lab results show that about 5% of the LiCl co- precipitated with the non-Lithium salts. This co-precipitated LiCl is dissolved in the liquid portion of the precipitant and, without being bound by theory, in a commercial process, could be recovered using a centrifuge and fed back into the VMD. In a commercial process, the VMD system will be designed such that the non-Lithium salts will be removed as they are precipitated out of solution.
  • the 810 liter feed sample, item 1102, having an LiCl concentration of 1500 ppm was first heated to 60°C before passing through the membrane run on KMX’s pilot scale VMD 1104 wherein 82% of water was recovered (1110), and the LiCl concentration is increased to about 11,800 ppm and TDS about 250,000 ppm.
  • the feed sample is run on KMX's lab scale VMD 1106 to recover 93% of water in the second stage, (1112), bringing the total water removal to 98%.
  • the salt removal shown in Item 1108 is 95% of NaCl, 96% of KCl and 88% of CaCl2.
  • Step 1 806, of vacuum membrane distillation (VMD) concentrates the feed sample to remove 70% of water resulting in NaCl removal, 808.
  • Step 2 of VMD is further concentration, 810, which removes a total of 95% of water resulting in KCl recovery, 812, followed by recovery of LiCl and MgCl2.
  • the two concentration steps 806 and 810 result in 95% water recovery, item 814, with less than 10 ppm total dissolved solids (TDS) remaining. At that point, the concentrated feed was removed from the feed tank.
  • FIGS.29A and 29B The analysis of the concentrate and permeate are shown in FIGS.29A and 29B (Tables 11 and 12).
  • a synthetic brine (200 liters) produced to have the same composition as the final Pilot unit concentrate (see FIG 29B, Table 12) was further concentrated in the Lab unit to about 300,000 ppm TDS at which point, the NaCl in the sample began to drop out of solution.
  • the VMD was stopped at this point, the concentrate cooled and additional NaCl precipitated out. Once the precipitation was complete, the remaining concentrate was re-heated, returned to the VMD and the process repeated until 95% of the NaCl, 96% of the KCl and 88% of the CaCl2 were removed.
  • the KMX VMD successfully concentrated a non-direct lithium extraction/Post RO Lithium brine to 200,000 ppm.
  • the trial also demonstrated the recovery of 95% of the LiCl Lithium in the original sample at about a 70% purity level (FIG.31). While not being bound by theory, it is believed that by starting with a larger sample volume in future trials, the process could be continued to remove additional non-Lithium salts and deliver an even higher LiCl purity level. It is also believed that the 5% of LiCl that co- precipitated with the non-Lithium salts can be recovered using a centrifuge.
  • the trial confirmed the robustness of the Generation 3 KMX membrane at high salinity levels (up to 380,000 ppm TDS), with no “wetting” and very little seepage.
  • the trial also demonstrated the ability of the membrane to recover very high-quality water ( ⁇ 10 TDS) for re-use, recovering 98% of the water from the initial feed.
  • the KMX VMD technology is a very viable option for concentration of a non- DLE/Post RO stream and recovery of high quality LiCl and water from the stream.
  • Step 1 Using a conventional RO the samples were treated to a TDS concentration level of about 260,000 ppm of which about 235,000 ppm was lithium chloride.
  • Step 2 In first stage of VMD application the RO concentrate of step 1 was processed to a lithium concentration of about 11,800 ppm.
  • Step 3 In first stage of VMD application the RO concentrate of step 1 was processed to a lithium concentration of about 11,800 ppm.
  • step 1 of VMD was processed in 26 sequential rounds of operation: concentration, crystallization and separation until a LiCl concentration of over 235,000ppm (FIG.28; FIG 36, Table 1368.8% of 341981 ppm total final concentrate) was obtained while Page 48 of 56 232614 most of the NaCl was separated, leaving only about 8400 ppm in the total final concentrate.
  • Experimental Procedure [0237] A low lithium concentration sample initially from a geologic source was pretreated with an RO to boost its initial concentration to the limits of conventional RO. Then, in previous work, this brine sample was concentrated using KMX VMD to near saturation of dominant salt which was NaCl using our standard concentrations methods.
  • Each concentration step consisted of running first the feed, and subsequently the concentrated liquid post separation from the previous round, in the VMD until the sample was saturated and could not be concentrated any further due to produced crystals within the system that blocked the fibers.
  • the VMD was operated at nominally 70°C, 120 mBar and 12.7 lmh (liters per square meter per hour).
  • the concentration step produced a saturated solution and permeate at lower than 10 ppm (25 of 26 times) and one at 50 ppm.
  • Crystallization step The saturated solution was transferred to the crystallizer and cooled in the freezer promoting the formation of crystals.
  • Separation step The Separation was achieved using decantation, vacuum filtration and ultrafiltration.
  • Decantation separated settled solids and most of the saturated solution.
  • the vacuum filtration separated the settled solids from the free saturated solution associated with the solids.
  • the filtered liquid and the decanted liquid were then combined and run through an ultra-filtration unit separating the remaining suspended solids from the saturated liquid.
  • This clarified saturated solution was then used as the feed for the next round of Total Brine Page 49 of 56 232614 Extraction. These three steps were repeated though all 26 rounds each time concentrating and enriching the Lithium Chloride in the saturated solution.
  • the Lithium Chloride concentration was about 1,800 ppm and represented 4.5% of the dissolved solids.
  • the Lithium Chloride was 235,000 ppm and represented 70% of the dissolved solids.
  • Each Concentration step was run to the equilibrium of the saturated solution under VMD conditions.
  • the permeate was calculated via the difference of the mass of water from the beginning to the end of the concentration step.
  • the concentration of the material being fed to the crystallizer could be calculated.
  • the equilibrium of the solution under the crystallizer conditions could be calculated, determining the mass and nature of the precipitation.
  • the precipitated material could be removed from the mixture and determine the content of the clarified concentrate ready to be moved to the next round.
  • the simulated results show trends similar to those in the experimental results.
  • Figure 36 provides an overview of initial feed salt quantities and TDS in the pilot scale trial, and parts 1 and 2 of the lab trial as well as the final concentrate salt quantities and TDS of the final concentrate from part 2 of the lab trial. It is seen that the total dissolved solids is increased from about 4.62 wt% to about 34.2 wt%. In the final concentrate, 68.8% of the total salt contents is LiCl. Page 50 of 56 232614 [0246]
  • Figure 37 shows the total water removed in the pilot scale trial and parts 1 and 2 of the lab trial, discussed in the preceding paragraph.
  • Figure 38 depicts mass and percentage of salts removed from the 26 rounds of processing in the KMX Lab VMD unit indicated for Rounds 1-13 collectively and rounds 14-26 collectively.
  • An embodiment is an implementation or example of the present disclosure.
  • Reference in the specification to “an embodiment,” “one embodiment,” “some embodiments,” “one particular embodiment,” “an exemplary embodiment,” or “other embodiments,” or the like, means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the invention.
  • a numeric value may have a value that is +/ ⁇ 0.1% of the stated value (or range of values), +/ ⁇ 1% of the stated value (or range of values), +/ ⁇ 2% of the stated value (or range of values), +/ ⁇ 5% of the stated value (or range of values), +/ ⁇ 10% of the stated value (or range of values), etc.
  • Any numerical range recited herein is intended to include all sub-ranges subsumed therein.
  • Page 51 of 56 232614 [0251] the method of performing the present disclosure may occur in a sequence different than those described herein. Accordingly, no sequence of the method should be read as a limitation unless explicitly stated. It is recognizable that performing some of the steps of the method in a different order could achieve a similar result.

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Abstract

Salts are removed from a salt-rich brine by a combined concentration-crystallization-separation process. High purity salts are obtained by sequential separation and also a very low TDS permeate water was produced.

Description

232614 TOTAL BRINE EXTRACTION USING A VACUUM MEMBRANE DISTILLATION – INTEGRATED CRYSTALLIZATION REACTOR (VMD-ICR) SYSTEM TECHNICAL FIELD [0001] The present disclosure relates generally to the field of water purification. More particularly, the present disclosure relates to methods of concentrating brine streams and related systems. More specifically, the present disclosure relates to methods and systems for concentrating and separating salts and other dissolved solids from a water stream. The methods and systems are useful to treat water streams such as ground water, surface water, drinking water, wastewater, industrial process water, cooling water, and the like. BACKGROUND [0002] The water supply of various parts of the world is precarious. Energy efficient desalination processes are required. Further, with the emerging electric car market, metals not previously part of traditional automobiles are now required for the construction of many parts of the car, in particular, lithium, as electric power storage. The two problems may be solved by processes and systems disclosed herein. SUMMARY [0003] In one aspect, an exemplary embodiment of the present disclosure may provide a process of purifying water comprising: providing an aqueous liquid feed stream comprising at least one salt; concentrating the at least one to near saturation or greater; crystallizing the at least one salt out of the feed stream to produce a slurry of the at least one salt; and separating salt crystals from the salt slurry. [0004] In another aspect, an exemplary embodiment of the present disclosure may provide an integrated crystallization reactor (ICR) comprising: a vacuum membrane distillation system; a separation system selected from the group consisting of coarse filtration, microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO), and a hydrocyclone (HC). Page 1 of 56 232614 [0005] In this exemplary embodiment or another exemplary embodiment, the disclosure provides a distillation apparatus including: a vacuum membrane distillation bundle; an integrated crystallization reactor comprising a chamber housed within a double walled generally cylindrical body, an inlet and an outlet; and a hydrocyclone with inlet and outlet lines, or a MF or a UF or a NF membrane system, preferably tubular membranes, capable of working at high solid loads (high density). [0006] In this exemplary embodiment or another exemplary embodiment, the disclosure provides: a double walled reactor defining a cavity or reaction space and having a liquid between the walls. In this exemplary embodiment or another exemplary embodiment, a tank with a cooling jacket is provided to reduce the temperature make larger and denser crystals and to accelerate precipitation without using a membrane system. In this exemplary embodiment or another exemplary embodiment, the temperature may be raised instead of lowered. [0007] In this exemplary embodiment or another exemplary embodiment, the disclosure provides: a process of purifying saltwater containing at least one salt, comprising: introducing the salt water into a pretreatment device selected from the group consisting of reverse osmosis, ultrafiltration, nanofiltration and microfiltration to afford a first permeate; transferring the first permeate to a VMD unit; transferring the concentrate from the VMD unit to a double-walled crystallization reactor, the reactor comprising a cooling jacket, in reciprocal fluid connection with the VMD unit to afford a supersaturated salt solution; transferring a high quality permeate product to be reused and fed into potential potable water streams; transferring the supersaturated salt solution to a cyclone to separate at least a portion of the salt from the supersaturated solution; and recycling at least a portion of the supersaturated solution to the VMD unit. [0008] Yet another aspect of the disclosure is a process of extracting salts from a feed water, comprising: providing a feed stream including at least one dissolved salt; introducing the feed stream to at least one VMD unit, to afford at least one of a (i) permeate, (ii) a high purity water and (iii) seepage; wherein the VMD underflow is transferred to a separation process including at least one UF system and one ultrafiltration tank; and wherein the ultrafiltration reject/overflow is transferred to a crystallization process including at least one crystallizer tank. Page 2 of 56 232614 [0009] Another aspect of the disclosure is a process of salt crystallization and separation, comprising: providing a liquid feed stream comprising a solution of at least one salt; concentrating the solution to near saturation (for example, at least 60%, for example at least any of the following: 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5%, 99.9%); crystallizing the at least one salt out of the feed stream to produce a slurry of the at least one salt; and separating salt crystals from the salt slurry. [0010] In this exemplary embodiment or another exemplary embodiment, the process provides that pure water is also produced. In this exemplary embodiment or another exemplary embodiment, pure water includes substantially fully separated salts, that is, TDS (total dissolved solids) at an amount of less than 1000 ppm, less than 900ppm, less than 800ppm; less than 700 ppm; less than 600 ppm; less than 500 ppm; less than 400 ppm; less than 300 ppm; less than 200 ppm; less than 100 ppm; less than 75 ppm; less than 50 ppm; less than 25 ppm; less than 10 ppm; or less than 5 ppm. References to "TDS" means "ppm TDS" even when "ppm" is not explicitly mentioned. [0011] In this exemplary embodiment or another exemplary embodiment, concentrating the at least one salt is performed by vacuum membrane distillation to produce a concentrated feed stream. In this exemplary embodiment or another exemplary embodiment, crystallizing the at least one salt comprises adjusting the temperature of the concentrated feed stream and/or of the crystallizer until at least a portion of the least soluble salt precipitates out of solution. [0012] In this exemplary embodiment or another exemplary embodiment, separating salt crystals from the salt slurry comprises at least one selected from ultrafiltration, hydrocyclone filtration, coarse filtration, microfiltration and nanofiltration. In this exemplary embodiment or another exemplary embodiment, a hydrophobic porous membrane is used for vacuum membrane distillation. [0013] In this exemplary embodiment or another exemplary embodiment, coarse filtration may involve filters having pore sizes of 10 microns to 2000 microns, 50 microns to 1000 microns, 100 microns to 500 microns, and values within the foregoing ranges. [0014] In this exemplary embodiment or another exemplary embodiment, the hydrophobic porous membrane has a pore size of less than 0.5 micron, preferably Page 3 of 56 232614 about 0.05 micron to about 0.45 micron, preferably about 0.2 micron to about 0.45 micron, preferably about 0.25 micron to about 0.45 micron. [0015] In this exemplary embodiment or another exemplary embodiment, concentration is carried out by a system that includes at least one of a concentrator, crystallizer and a separator, wherein the concentrator concentrates at least one salt in the solution to at least near saturation. In this exemplary embodiment or another exemplary embodiment, the system includes at least one concentrator and at least one of a crystallizer and a separator. [0016] In this exemplary embodiment or another exemplary embodiment, near saturation is defined as, for example, at least 60%, or for example at least any of the following: 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5%, 99.9% of saturation or other values in between the foregoing. In this exemplary embodiment or another exemplary embodiment, a definition of "near saturation" or another useful parameter in certain embodiments of the disclosure is a concentration greater than the saturation concentration of the crystallizer but not necessarily greater than the saturation concentration of the concentrator. Preferably the "near saturation concentration" is also greater than the saturation concentration of the concentrator. However, there are advantages for running the concentrator below the saturation level with respect to its operating conditions but above the saturation level of the crystallizer's operating conditions. In this exemplary embodiment or another exemplary embodiment, the concentrator operates at conditions independent of the operating conditions of the crystallizer. [0017] In this exemplary embodiment or another exemplary embodiment, after the solution is transferred from the concentrator to the crystallizer the solution is allowed to crystallize, as it is supersaturated relative to the crystallizer conditions. In this exemplary embodiment or another exemplary embodiment, the process further comprises transferring the solution to the separator where the crystals are removed from the solution. In this exemplary embodiment or another exemplary embodiment, the solution is saturated for at least one salt relative to the crystallizer conditions, but below saturation relative to the conditions of the concentrator. In this exemplary embodiment or another exemplary embodiment, the process comprises transferring or recycling the solution to the concentrator. In this exemplary embodiment or another exemplary embodiment, the repetition or cycling of the steps of Page 4 of 56 232614 concentration, crystallization and separation can continue as the salts are precipitated in order of least soluble to most soluble. [0018] In this exemplary embodiment or another exemplary embodiment, the products are a series of separated salts, purified water and a solution containing the most soluble salt. Further concentration, crystallization and separation steps can be undertaken until all salts and all dissolved solids are substantially fully separated or removed from the intake feed. Alternatively, the process can be continued to the end product or terminated earlier leaving a solution containing a mixture of the most soluble salts. Salts may also be coprecipitated producing a mineral that is a mixture of more than one salt, for example under the right conditions NaCl and KCl will coprecipitate. The salts may be separated by additional processing or left as a mixture of salts depending on the processing requirements. In this exemplary embodiment or another exemplary embodiment, the temperature within the crystallizer unit will be adjusted to a temperature causing the solution to be supersaturated. Additionally, time will be allowed for crystals to form. In this exemplary embodiment or another exemplary embodiment, the process further includes filtering the temperature-adjusted concentrated feed stream to afford salt crystals and permeate. In this exemplary embodiment or another exemplary embodiment, the process further includes entering the permeate into a VMD stage. In this exemplary embodiment or another exemplary embodiment, the process further includes filtering the concentrated feed stream to produce a slurry of at least one salt and a solution of at least a second salt. In this exemplary embodiment or another exemplary embodiment, the process further includes producing a mixture of dissolved solids and precipitated solids. [0019] Another aspect of the disclosure is a process for salt crystallization and separation a concentrate from a concentrator when the concentrator maintains the salt solutions at below salt saturation, wherein the process order is (i) concentrator, (ii) crystallizer, (iii) separator. [0020] Another aspect of the disclosure is a process of purifying a feed stream containing water, comprising: providing a feed stream to at least one crystallizer to provide a concentrated output stream; directing at least a first portion of the concentrator output stream to a crystallizer which outputs a saturated solution and Page 5 of 56 232614 salt crystals; and directing a second portion of the concentrator output stream to a separator; directing a third portion of the concentrator output stream to a seepage tank to form seepage; directing the seepage to the input stream; directing at least a first portion from the concentrator to a permeate vessel to form a permeate; directing at least a second portion of the condensed concentrated output through a filter to provide a filter cake and a permeate; directing at least a portion of the permeate to the feed stream; wherein at least a portion of the filter cake comprises salt crystals. [0021] The Vacuum Membrane Distillation stage of the process is the heart of VMD-ICR process. In this exemplary embodiment or another exemplary embodiment, VMD includes three stages based on temperature: A) the hot feed water circulation stage; B) the produced vapor stage and C) the cooling stage. [0022] In this exemplary embodiment or another exemplary embodiment, the feed circulation water can operate within the range of about 35°C to about 75°C, or about 40°C to 70°C, or about 45°C to about 65°C. The feed water circulates in a loop starting from feed water tank and then into the membrane modules where it is partially concentrated by losing pure water as vapor. [0023] In this exemplary embodiment or another exemplary embodiment, the produced vapor temperature is usually about 1°C to about 10°C, or about 2 °C to about 9 °C, or about 3 °C to about 8 °C, or about 4°C to about 7°C or about 5°C or about 6°C, lower than feed water temperature. In some embodiments, the produced vapor may have a temperature that is higher than the feed water temperature by as much as 50°C, or 40 °C, or 30 °C, or 30 °C or 15 °C, or higher, or other values in between. A greater temperature drop leads to a higher produced flux. The cold/cooler portion of VMD includes the condensers where produced vapor condensed into near pure water. The temperature of these condensers is at least a few degrees lower than that of the produced vapor, for example in the cooling loop a cold liquid has a temperature of around 5°C, 10°C or 15°C (or values therebetween). [0024] In this exemplary embodiment or another exemplary embodiment, within a VMD system, membrane modules work in a low pressure which is limited to a total water entry pressure (WEP) of about 15-30 psi, 17-27 psi, 20-25 psi, or about 24psi depending on the hydrophobic membrane used. The water pressure inside a Page 6 of 56 232614 membrane module is limited to less than about 10 psi. Vacuum levels typically used in VMD are around -13 to about -14 psi, of which 99.9% of that value is theoretically possible with VMD, however the cost of maintaining such a high level vacuum is not justified. In one example, a membrane with a WEP of about 30 to about 50 psi would allow water pressure of about 15 to about 35 psi, this may be necessary hypersaline solutions are achieved. [0025] In this exemplary embodiment or another exemplary embodiment, VMD can have one or more membrane modules, where each membrane module has a membrane bundle having a hollow fiber membrane with a surface area of about 1 to about 20 m2, such as about 5 to 15 m2 or about 7 to 13 m2 or about 10m2. A membrane module operates usually in an inside-out mode of operation wherein liquid goes inside the lumens of fibers while the vapor is produced in the shell and is collected through vapor collectors which are connected to vapor condensers. The opposite configuration is also possible. Alternate configurations can also be used: such as a flat sheet or spiral wound. [0026] In this exemplary embodiment or another exemplary embodiment, the vapor condensers may be shell-and-tube heat exchangers or plate-and-frame heat exchangers operating via a cooling liquid, cooled by a chiller, which is circulated within the cooling loop, inside the tube, or opposite side of the plate, to adsorb the heat and condense the vapor, inside the shell. Vapor can alternatively be on the tube side. [0027] In this exemplary embodiment or another exemplary embodiment, the system includes a seepage vessel. Each membrane module can produce some seepage which is collected into the seepage vessel; although some of the seepage may be condensed vapor inside the shell at early time of operation before modules being warmed. This vessel is equipped with level detectors directing a seepage pump to collect seepage and return it to the feed tank, permeate tank or alternative processing tank. [0028] In this exemplary embodiment or another exemplary embodiment, the distillation system includes a permeate vessel where the VMD-produced vapor, after being condensed into liquid water, is collected. The vessel may be equipped with Page 7 of 56 232614 level indicators and controls. This permeate is a very high-quality water, that is, salts substantially fully separated out, and when required, the permeate will be pumped to the permeate storage tanks. [0029] In this exemplary embodiment or another exemplary embodiment, a vacuum pump is used to establish the desired vacuum level. The vacuum pump is designed to produce the vacuum at the beginning and during the process. [0030] In this exemplary embodiment or another exemplary embodiment, a heat exchanger is used to heat the feed water to desired temperature for example in the range of about 40 °C to about 75°C, and other ranges disclosed elsewhere herein. The source of heat can be different from renewable energy sources to available waste energy, electricity, as well as legacy energy sources. If required the VMD process can be integrated with energy recovery units such as a heat pump (HP) and mechanical vapor compression (VMC). [0031] In this exemplary embodiment or another exemplary embodiment, the VMD system may include at least two feed tanks where one will be in operation and will, in a first tank, concentrate until near saturation of the least soluble salt. The nearly saturated solution from the feed tank with saturated salt solution will be sent to a crystallization tank where it will be cooled down to speed up crystallization where it is possible. The first VMD feed tank will then be filled with a fresh batch of the same feed. [0032] In this exemplary embodiment or another exemplary embodiment, in the crystallization tank, larger and heavier crystals will precipitate and separate. The supernatant of the crystallization tank with microcrystals will be sent to ultrafiltration (UF) where smaller crystals will be separated in the UF concentrate while UF permeate will be sent to the feed tank after it is heated to a desired temperature (depending on the solubility of remaining salts) with, for example, a heat exchanger. The UF concentrate will be sent back to the crystallization tank. The solid crystals will be sent to a solid handling process such a filter press. The UF filtrate (permeate) will be sent to the VMD feed tank. Page 8 of 56 232614 [0033] In this exemplary embodiment or another exemplary embodiment, when the solution in the feed tank reaches a desired concentration, the solution will be sent to the crystallization tank. This is a temperature-controlled tank such as a double jacket tank to control the solution temperature within a desired range. The temperature of this tank will be independent of that of the concentrator and controlled at a temperature to promote crystallization. [0034] In this exemplary embodiment or another exemplary embodiment, the VMD-ICR system can also be designed without a crystallization tank meaning the size of the crystals and their separation will be managed within the feed tank and a separation unit such as reverse osmosis, ultrafiltration or other filtration system (microfiltration, nanofiltration, hydrocyclone). [0035] In this exemplary embodiment or another exemplary embodiment, ultrafiltration (UF) may be used as a separator. The separator (for example UF) molecular cutoff (about 50,000 daltons, about 100,000 daltons, about 150,000 daltons, about 200,000 daltons or about 250,000 daltons) is chosen to be very tight to let only dissolved solids and macromolecules pass through so that all particulates including microcrystals will be separated. The UF membrane could be ceramic or organic materials. Ceramic membranes can be used at high pressures and temperatures (such as 80, 90, 100°C) while organic membranes such as paper, cellulose acetate, PVDF, polysulfide, PTFE, and polymeric membranes are more useful in the range of 10-40°C (PS, PVDF, PTFE membranes can stand to about 70°C ). The UF system is equipped with a clean in place (CIP) system for cleaning of the UF membrane when it is required. [0036] In this exemplary embodiment or another exemplary embodiment, a salt concentrator operates at or above saturation where the process flow is from concentration/VMD to crystallization to separation. [0037] In this exemplary embodiment or another exemplary embodiment, a mode of operation is similar to the operation mode where VMD operates below saturation. VMD produces crystals beyond saturation which can be removed by a separation process such as UF prior to entering the crystallization tank. A sample at Page 9 of 56 232614 or above saturation can also be run in the order concentration, separation, then crystallization. [0038] Further embodiments of the disclosure include a salt crystallization and separation system comprising (i) a concentrator; (ii) a crystallizer and (iii) a separator. [0039] In this exemplary embodiment or another exemplary embodiment, the concentrator comprises: at least one VMD module; at least one VMD feed tank; a heat source; a vacuum source and a cooling source; circulation pumps; heat exchangers, for heating the feed and condensing the vapor. Further, the crystallizer comprises a process tank comprising at least one temperature control mechanism; a crystal recovery system such as filter press; transfer pumps; the separator comprises at least one filtration component selected from microfiltration, ultrafiltration, nanofiltration, and a filtrate tank. [0040] In one aspect, the disclosure provides a process of separating at least one salt from a liquid stream comprising the at least one salt, the process comprising: providing a liquid stream comprising the at least one salt; concentrating the liquid stream to at least near saturation; crystallizing the at least one salt out of the liquid stream to produce a slurry comprising crystals of the at least one salt; and separating the salt crystals from the salt slurry. [0041] In this exemplary embodiment or another exemplary embodiment, concentrating the liquid feed stream comprises treating the liquid stream with vacuum membrane distillation. In this exemplary embodiment or another exemplary embodiment, crystallizing the at least one salt comprises adjusting the temperature of the liquid stream and/or of the crystallizer until at least a portion of a least soluble salt precipitates out of solution. In this exemplary embodiment or another exemplary embodiment, separating salt crystals from the salt slurry comprises at least one selected from coarse filtration, hydrocyclone filtration, ultrafiltration, microfiltration and nanofiltration. In this exemplary embodiment or another exemplary embodiment, the at least one hydrophobic porous membrane is used for vacuum membrane distillation. In this exemplary embodiment or another exemplary embodiment, the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 Page 10 of 56 232614 m2, or about 1 to about 20 m2, preferably about 5 to 15 m2, more preferably about 7 to 13 m2 and still more preferably about 10m2. In this exemplary embodiment or another exemplary embodiment, the hydrophobic porous membrane has a pore size of less than 0.5 micron, preferably about 0.05 micron to about 0.45 micron, preferably about 0.2 micron to about 0.45 micron, preferably about 0.25 micron to about 0.45 micron. In this exemplary embodiment or another exemplary embodiment, near saturation is defined as at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, at least 99.5%, or at least 99.9% of the saturation concentration of at least one salt, or other values in between the foregoing. In this exemplary embodiment or another exemplary embodiment, near saturation is defined as a concentration greater than the saturation concentration obtainable by the crystallizer. [0042] In another aspect, the invention provides a process of purifying a feed stream containing water, comprising: providing a feed stream to at least one crystallizer to provide a more concentrated output stream; directing at least a first portion of the concentrator output stream to a crystallizer which will output saturation solution and salt crystals; directing a second portion of the concentrator output stream to a separator; directing a third portion of the concentrator output stream to a seepage tank to form seepage; directing the seepage to the input stream; directing at least a first portion from the concentrator to a permeate vessel to form a permeate; directing at least a second portion of the condensed concentrated output through a filter to provide a filter cake and a permeate; directing at least a portion of the permeate to the feed stream; and wherein at least a portion of the filter cake comprises salt crystals. [0043] In still another aspect, the invention provides: a system for removing salts from a liquid stream, comprising: a concentrator configured to concentrate at least one salt to at least near the saturation point of the at least one salt; a crystallizer configured to crystallize at least one salt; and, a separator configured to separate crystals of the at least one salt from the liquid stream. In this exemplary embodiment or another exemplary embodiment, the concentrator comprises: a vacuum membrane distillation unit comprising at least one porous hollow fiber membrane. In this exemplary embodiment or another exemplary embodiment, the Page 11 of 56 232614 the crystallizer comprises: at least one condenser. In this exemplary embodiment or another exemplary embodiment, the separator comprises: at least one selected from a coarse filtration unit, a hydrocyclone filtration unit, an ultrafiltration unit, a microfiltration unit and a nanofiltration unit. In this exemplary embodiment or another exemplary embodiment, the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 m2, or about 1 to about 20 m2, preferably about 5 to 15 m2, more preferably about 7 to 13 m2 and still more preferably about 10m2. In this exemplary embodiment or another exemplary embodiment, the at least one porous hollow fiber membrane has an average pore diameter of 0.5 micron, preferably about 0.05 micron to about 0.45 micron, more preferably about 0.2 micron to about 0.45 micron, and still more preferably about 0.25 micron to about 0.45 micron. In this exemplary embodiment or another exemplary embodiment, the at least one condenser comprises or is selected from: shell-and-tube heat exchanger, plate-and-frame heat exchanger, and a chiller including a cooling loop. In this exemplary embodiment or another exemplary embodiment, the system is configured to operate in an inside-out mode of operation wherein a liquid feed stream enters lumens of hollow fibers while a vapor is produced in a shell and is collected through vapor collectors which are connected to vapor condensers. In this exemplary embodiment or another exemplary embodiment, the system further comprises at least one of a seepage vessel and a permeate vessel. In this exemplary embodiment or another exemplary embodiment, the separator has a molecular cutoff of about 1 to about 250,000 daltons, for example, about 50,000 daltons, about 100,000 daltons, about 150,000 daltons, about 200,000 daltons or about 250,000 daltons or ranges between the foregoing values or values within the foregoing ranges.. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0044] Sample embodiments of the present disclosure are set forth in the following description, are shown in the drawings and are particularly and distinctly pointed out and set forth in the appended claims. [0045] Figure 1 (FIG.1) depicts a simplified overview of process flow of an embodiment of the disclosure. Page 12 of 56 232614 [0046] Figure 2 (FIG.2) depicts an exemplary process flow of the disclosure. [0047] Figure 3 (FIG.3) depicts an exemplary process flow of the disclosure. [0048] Figure 4 (FIG.4) depicts an exemplary process flow of the disclosure. [0049] Figure 4A (FIG.4A) depicts a portion of an exemplary process flow of the disclosure as shown in FIG.4. [0050] Figure 5 (FIG.5) is a longitudinal cross-section of a membrane distillation module of an embodiment of the disclosure. [0051] Figure 5A (FIG.5A) is a detailed view of an embodiment of Figure 5. [0052] Figure 5B (FIG.5B) is a detailed view of an embodiment of Figure 5. [0053] Figure 6 (FIG.6) is an exploded view of an embodiment of Figure 5. [0054] Figure 7 (FIG.7) depicts a relation between concentration and temperature for selected salts. [0055] Figure 8 (FIG.8) is a schematic overview of an exemplary separation process flow. [0056] Figure 9 (FIG.9) depicts an example of the process flow of Figure 8. [0057] Figure 10 (FIG.10) depicts mass balance results of an exemplary process flow of Figure 8. [0058] Figure 11 (FIG.11) depicts the feed flow composition for the process of Figure 8. [0059] Figure 12 (FIG.12) depicts estimated energy consumption of an embodiment of the disclosure. [0060] Figure 13A (FIG.13A) depicts actual precipitate and composition quantities of an embodiment of the disclosure. [0061] Figure 13B (FIG.13B) precipitate proportions and overall salts removed of an embodiment of the disclosure. [0062] Figure 13C (FIG.13C) depicts actual precipitate and composition quantities of an embodiment of the disclosure. [0063] Figure 13D (FIG.13D) depicts estimated results of six rounds of room temperature precipitation of an embodiment of the disclosure. [0064] Figure 13E (FIG.13E) depicts estimated results of room temperature precipitation of an embodiment of the disclosure. [0065] Figure 13F (FIG.13F) depicts actual measurements of salts in supernatant from six batches of separated salts. Page 13 of 56 232614 [0066] Figure 14 (FIG.14) depicts quality and quantity of water removed during six rounds of separation. [0067] Figures 15A-15J (FIGS.15A-15J) depict potassium chloride removal in various embodiments of the disclosure. [0068] [0069] Figure 16 (FIG.16) depicts a ternary phase diagram of two salts and water. [0070] Figure 17 (FIG.17) depicts a graphical relation between solubility and temperature of four salts. [0071] Figure 18 (FIG.18) is a graphical depiction of a relation of solids by mass vs. permeate volume for an embodiment of the disclosure. [0072] Figure 19 (FIG.19) shows the data for Figure 18. [0073] Figure 20 (FIG.20) is a graphical depiction of a relation of solids by mass vs. permeate volume for three fractions of an embodiment of the disclosure. [0074] Figure 21 (FIG.21) shows the data for Figure 20. [0075] Figure 22 (FIG.22) depicts a salt analysis of crystals obtained at the vacuum membrane distillation stage of an embodiment of the disclosure. [0076] Figure 23 (FIG.23) depicts a relation of solids by mass vs. permeate volume with a smoothed total precipitate curve of an embodiment of the disclosure. [0077] Figure 24 (FIG.24) shows the data for Figure 23. [0078] Figure 25 (FIG.25) depicts a relation of solids by mass vs. permeate volume with total precipitate produced at +22°C of an embodiment of the disclosure. [0079] Figure 26 (FIG.26) shows the relation between precipitate mass produced in each round of precipitation vs. permeate volume of an embodiment of the disclosure. [0080] Figure 27 (FIG.27) shows the data for Figure 26. [0081] Figure 28 (FIG.28) is a schematic overview of an exemplary separation process flow. [0082] Figure 29A (FIG.29A) shows a pilot unit feed composition and concentrations after one step of vacuum membrane distillation of the embodiment of Figure 28. [0083] Figure 29B (FIG.29B) depicts initial concentration of lab unit feed water of the embodiment of Figure 28. Page 14 of 56 232614 [0084] Figure 30 (FIG.30) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0085] Figure 31 (FIG.31) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0086] Figure 32 (FIG.32) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0087] Figure 33 (FIG.33) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0088] Figure 34 (FIG.34) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0089] Figure 35 (FIG.35) depicts the concentrations of four salts over 26 rounds of vacuum membrane distillation of an embodiment of the disclosure. [0090] Figure 36 (FIG.36) provides an overview of initial feed and final processed salt quantities and TDS in an embodiment of the disclosure. [0091] Figure 37 (FIG.37) shows the total water removed in an embodiment of the disclosure. [0092] Figure 38 (FIG.38) depicts mass and percentage of salts removed from 26 rounds of processing of an embodiment of the disclosure. [0093] Similar numbers refer to similar parts throughout the drawings. [0094] The drawings illustrate, and do not limit, the scope of this disclosure. DETAILED DESCRIPTION [0095] Phase I. [0096] The vacuum membrane distillation-integrated crystallization reactor (VMD-ICR) is designed to concentrate brine streams beyond the point of individual salt saturation levels by adjusting the operation conditions, particularly temperature and flow conditions. Under these conditions initially micro crystals and gradually macro crystals will form that can be separated sequentially from low solubility to high solubility. Obtaining relatively pure salt crystals is possible by removing lower solubility salts as they come out of solution while continuing to concentrate the remaining salts. The production and separation of the produced micro crystals in the VMD-ICR form the heart of the disclosed process. Page 15 of 56 232614 [0097] The process can be operated in a manner that allows small crystals to form, allowing separation of less soluble salt crystals first in a mix solution of salts. The conditions of the super saturated salt solution will be changed in the ICR to crystallize the salts. This has been demonstrated in pilot scale trails. [0098] The ICR can produce fine crystals that can be converted to larger crystals by controlling the temperature, pressure, flow rate and flow velocity. Suitable techniques for separation of fine crystals include microfiltration (MF) ultrafiltration (UF), nanofiltration (NF) or any separation technology that can effectively separate the produced micro/macro crystals. [0099] A foundational step of the disclosure is the production and separation of pure micro crystals in the VMD-ICR. This can be achieved by the combination of three different unit operations: VMD, crystallization and separation as shown in FIGS.2 and 3. [0100] The precipitants are recovered as a series of solids, high purity water is produced, and a concentrate of the most soluble salt is produced (if the process is not run to completion a mixture of the most soluble salts will be produced). The three unit operations are a concentrator, a crystallizer and a separator. Technologies such as evaporators, reverse osmosis, forward osmosis, and distillation are examples of concentrators in the system. Likewise, ultrafiltration, microfiltration, coarse filtration, hydro cyclones, and settling tanks are examples of suitable separation technologies, but other separators could be used. Typically, bulk solution crystallizers, precipitation vessels, or melt crystallizers will be used, but other types of crystallizers may also be used. [0101] The operation of this system is based on four principles. The concentrator, crystallizer and separator need to operate under different conditions (temperature, pressure, flow, etc.). The concentrator needs to be able to concentrate the solution to a super saturated solution relative to the operating conditions of the crystallizer. The crystallizer must be controllable allowing a salt precipitation to form. The separator must be able to remove the solids and produce the internal recycle with an unsaturated solution relative to the operating conditions of the concentrator. [0102] Referring to FIG.1, which provides an overview of VMD-ICR system and process, VMD-ICR process 1 includes a three-stage system and process 2, which includes concentrator 2a (concentration), which produces concentrate 2b, Page 16 of 56 232614 flowing into crystallizer 2c (crystallization), which produces a slurry 2d of concentrated salts and water leading into separator 2e (separation). Feed flow 3 containing at least one salt is feeds into concentrator 2a to start the process. In the crystallizer 2c, at least one salt is crystallized/precipitated out of the concentrated feed to form a slurry 2d. Concentrator 2a also produces purified water 7. [0103] Slurry 2d is transferred to separator 2e, which physically separates salt crystals from a saturated solution of the nth salt. Separator 2e provides precipitants 1, 2, 3 through precipitant n-1 (indicated by reference numeral 4) and a saturated solution of the nth salt (indicated by reference numeral 5). An ever more concentrated solution from separator 8 is recycled (indicated by reference numeral 6) back to concentrator 2a. [0104] In FIG.2, the disclosure provides a more detailed process flow 10. The three major segments of the process in FIG.1 are shown in more detail in FIG.2, where process 10 includes concentration process 20, crystallization process 30 and separation process 40. [0105] In process 10, brine feed 90 is fed to VMD process tanks 100, 102 and 104. It will be appreciated that there can be any number of VMD process tanks. VMD process tanks 100, 102 and 104 act as settling tanks, and hold a supply of brine feed prior to entering VMD unit 118. Valves 100a, 100b, 102a, 102b, and 104a, when properly configured may allow settled solids to flow out of VMD process tanks 100, 102 and 104 which are moved by transfer pump 105 to filtration membrane 144, which may be a ceramic or organic membrane and may be classified as ultrafiltration, microfiltration, nanofiltration or other filtration types. [0106] The brine feed 90 may be heated in VMD process tanks 100, 102 and 104 using heated water provided by heat exchanger 114 which receives heated water from heater 112. Heated water is provided to VMD process tanks 100, 102 and 104 by proper operation of valves 114a and 114b. Heat may also be provided to VMD process tanks 100, 102 and 104 by proper operation of valve 110b, which directs heated water from heat exchanger 110 which also received heated water from heater 112. The foregoing processes are driven by process pump 106 and reheating pump 108. By proper operation of valves 102a, 102c and 104a, process pump 106 moves effluent from VMD process tanks 100, 102 and 104 through process heat exchanger 116 to VMD unit 118. VMD unit 118 has three outputs: (i) Page 17 of 56 232614 vapor which becomes condensate in main condenser 124, (which itself is maintained at cooler than ambient temperature by cooling source 126). VMD unit 118 also outputs seepage to seepage vessel 120. Seepage is an accumulation of liquids on the vapor side (low pressure side) of the VMD membrane system. Seepage through the hollow fiber membrane within VMD module 118 is also possible. Seepage is also possible due to imperfections in the VMD unit, such as leaky seals. Seepage is returned to VMD process tanks 100, 102 and 104 by proper operation of valves 120a, 122a and seepage pump 122. VMD unit 118 also recycles a portion of its input back to VMD process tanks 100, 102 and 104. [0107] Flow through VMD module 118 and permeate vessel 128 is driven by vacuum pump 132, with pulls a vacuum therethrough. The vacuum pulled on VMD module 118 is through seepage vessel 120. Seepage not pulled out of seepage vessel 120 is moved by seepage pump 122 and proper operation of valve 120a where it is returned to at least one of VMD process tanks 100, 102 and 104. Permeate vessel 128 outputs pure water through action of pump 130 and proper operation of valve 128a. [0108] Returning to the above discussion of flow motion by transfer pump 105, to, the flow traverses filtration membrane 144 and then by proper operation of valve 144a, enters crystallization tanks 160 and 162, which is the first step in crystallization process 30. [0109] Flow passing through filtration membrane 144 may also pass through clean-in-place (CIP) loop 146 by proper operation of valves 146a and 146b. CIP loop 146 washes the process water with dilute acid (acetic, hydrochloric, phosphoric or others) to dissolve any accumulated salts that have not been eliminated by filtration membrane 144. [0110] When valve 144a is closed, then feed flow passing through filtration membrane 144 either goes through CIP loop 146 or into filtration permeate tank 140, which, by proper operation of valve 140a and pump 142, is recycled through heat exchanger 114 and valves 114a, 114b to VMD process tanks 100, 102 and 104. [0111] Returning to the discussion of the first steps in crystallization process 30, crystallization tanks 160 and 162 each contain a cooling loop 163a and 163b, respectively. Cooling water is generated by chiller 126. As the temperature of the contents of crystallization tanks 160 and 162 cool, salts begin to precipitate out of Page 18 of 56 232614 solution. Such salts are concentrated, in some cases to the point of supersaturation, and pulled out of crystallization tanks 160 and 162 by crystallizer pump 170 and passed through a filter, such as filter press 174 through proper operation of valves 160a, 160b, 160c, 162a and 162b. The filtrate is high purity salt crystals, while the permeate is returned to the VMD process tanks 100, 102 and 104 by UF permeate pump 142. [0112] In FIG.3, a more detailed process flow 310 is provided. Process flow 310 is an alternative to process flow 10 as will be seen. FIG.3 depicts process 310 including concentration process 320, crystallization process 330 and separation process 340. [0113] In concentration process 320, brine feed 390 is fed to VMD process tanks 400 and 402. It will be appreciated that there can be any number of VMD process tanks. VMD process tanks 400 and 402 act as settling tanks, and hold a supply of brine feed prior to entering VMD unit 418. Valves 400a, 400b, 400c, 402a, and 402b, when properly configured may allow settled solids to flow out of VMD process tanks 400 and 402 which are moved by transfer pump 408 to crystallization tanks 440 and 442, which is the first step in crystallization process 330. The contents of VMD process tanks 400 and 402 are heated from heated water provided by heat exchanger 414 which receives heated water from heater 412. Heated water is provided to VMD process tanks 400 and 402 by proper operation of valves 410a, 412a and 414a. [0114] The foregoing processes are driven by process pump 406 and reheating pump 404. By proper operation of valves 400a, 400b, 400c, 400d, 400e, 402a, and 422a, process pump 406 moves effluent from VMD process tanks 400 and 402 through process heat exchanger 416 to VMD unit 418. VMD unit 418 has three outputs: (i) vapor which becomes condensate in main condenser 424, (which itself is maintained at cooler than produced vapor temperature by cooling source 426). VMD unit 418 also outputs seepage to seepage vessel 420. Seepage is an accumulation of liquids on the vapor side (low pressure side) of the VMD membrane system. Seepage through the hollow fiber membrane within VMD module 418 is also possible. Seepage is also possible due to imperfections in the VMD unit, such as leaky seals. Seepage is returned to VMD process tanks 400 and 402 by proper Page 19 of 56 232614 operation of valves 420a and 422a and seepage pump 422. VMD unit 418 also recycles a portion of its input back to VMD process tanks 400 and 402. [0115] Vapor flow through VMD module 418 and permeate vessel 428 is driven by vacuum pump 432, which pulls a vacuum therethrough. The vacuum pulled on VMD module 418 is through seepage vessel 420. Seepage not pulled out of seepage vessel 420 is moved by seepage pump 422 and proper operation of valve 420a where it is returned to at least one of VMD process tanks 400 and 402. Permeate vessel 428 outputs pure water through action of permeate pump 430 and proper operation of valve 428a. [0116] Returning to the above discussion of flow motion by transfer pump 408, the flow traverses valve 408a into crystallization tanks 440 and 442, which is the first step in crystallization process 30. Crystallization tanks 440 and 442 each contain a cooling loop 443a and 443b, respectively. Cooling water is generated by chiller 426. As the temperature of the contents of crystallization tanks 440 and 442 cool, salts begin to precipitate out of solution. [0117] Such salts are concentrated, in some cases to the point of supersaturation, and pulled out of crystallization tanks 440 and 442 by crystallizer pump 450 and passed through a filter, such as filter press 474 through proper operation of valves 440a, 440b, 440c, 442a and 442b. The filter cake is high purity salt crystals, while the permeate is returned to the VMD process tanks 400 and 402 by UF permeate pump 462. [0118] From crystallizer pump 450, by proper operation of valves 450a and 474a, a portion of the flow is directed to filtration membrane 464. Flow passing through filtration membrane 454 may also pass through clean-in-place (CIP) loop 466 by proper operation of valves 466a and 466b. CIP loop 466 washes the process water with dilute acid (acetic, hydrochloric, phosphoric or others) to dissolve any accumulated salts that have not been eliminated by filtration membrane 464. [0119] Returning to the discussion of the first steps in crystallization process 30, crystallization tanks 440 and 442 each contain a cooling loop 443a and 443b, respectively. Cooling water is generated by chiller 426. As the temperature of the contents of crystallization tanks 440 and 442 cool, salts begin to precipitate out of solution. Page 20 of 56 232614 [0120] Another embodiment of the invention is depicted in FIGS.4-1 and 4-2. Process Round 1, 710 begins with a liquid feed stream 705 entering VMD concentration step #1 710a, which produces supersaturate #1 710b, which is transferred to crystallization step #1 710c, producing slurry #1 710d, which is separated in separation step #1710e to afford salt crystals #1710f. A concentrate #1710g is recycled from separation #1710e to form the feed for VMD concentration step #2720, the start of process round #2. In various embodiments, process round #2 (720) and process round #3 (730) proceed exactly as process round #1, with analogous steps similarly numbered and with the concentrate #2730g moving to VMD concentration step #3. In various embodiments, process round 2 (720) and/or process round #3 (730) proceed differently from process round #1 (710) in terms of at least one of VMD flow and/or operating pressure; crystallization temperature or separation conditions. In one or more embodiments, each VMD concentration step involves at least one vacuum membrane distillation unit comprising at least one porous hollow fiber membrane. In one or more embodiments, each crystallization step involves at least one heat exchanger and/or cooling unit. In one or more embodiments, each separation step involves at least one of reverse osmosis, coarse filtration, hydrocyclone filtration, ultrafiltration, microfiltration and nanofiltration. [0121] VMD concentration step #1710a also produces permeate 710', while VMD concentration step #2 also produces permeate #2720' and VMD concentration step #3 also produces permeate #3730'. [0122] Advancing to the end of VMD concentration step #3, specifically crystals #3 are advanced to recrystallization #1730h, which is expanded in FIG.4A. FIG.4A depicts crystals #1730f entering hot recrystallization #3730h. Pure water 730f' also enters the recrystallization here. Hot recrystallization #3730h produces a hot recrystallization filtrate 730i and recrystallization crystals #3H 730l. Hot recrystallization filtrate 730i flows to cold recrystallization #3730j, which produces cold recrystallization filtrate 730k and cold recrystallization crystals #3F 730m. In this and the following paragraphs, and elsewhere herein, "H" indicates a hot recrystallization step or its result, "F" indicates a cold ("freezing") recrystallization step or its result, and "RT" indicates a room temperature recrystallization step or its result. Page 21 of 56 232614 [0123] Process Round 3 at separation #3 recycles concentrate #3 to feed Process Round #4, VMD concentration step #4740a, which produces supersaturate 740b, which is transferred to crystallization step #4-RT 740c, producing slurry #4 740d, which is separated in separation step #4-1740e to afford salt crystals #4-RT 740f. From separation step #4-1 740e a filtered supersaturate #4 is fed to crystallization #4F 740h, producing slurry #4F, which is separated in separation step #4-2740j into crystals #4F 740j and concentrate #4740k, which is recycled into VMD concentration step #5750a. [0124] In one embodiment, process round #5750 and process round #6760 proceed exactly as process round #4740, with analogous steps similarly numbered and with the concentrate #5750k moving to Process round 760, VMD concentration step #6. [0125] VMD concentration step #4740a also produces permeate 740', while VMD concentration step #5 also produces permeate #4750' and VMD concentration step #6 also produces permeate #6760'. [0126] FIG.5 depicts a longitudinal cross-section of a membrane distillation module 10 (HFDM - Hollow Fiber Distillation Module or just "Module") showing module shell 12, fiber membrane bundle 22 with module top cap 18, and module bottom cap 20. Module 10 is suitable for receiving the fiber membrane bundle 22 of the present disclosure. The module includes a housing comprising a module shell 12 having a module top flange 14 and a module bottom flange 16 at top and bottom ends, respectively, of module shell 12. Each flange may be manufactured from an engineered plastic and is connected to the module shell 12 via a chemical welding, fusing or gluing process. FIG.5A is an expanded view of FIG.5 showing Detail 5A: the module top cap 18 and threads. FIG.5B is an expanded view of FIG.5 showing Detail 5B: the module bottom cap 20 and threads 33. [0127] FIG.5A is an expanded view of Detail 5A of FIG.5 showing the shell 12, with flange 14; threads 33 on the outer diameter of a center core 32; and threads 35 on the inner diameter of module top cap 18. Center core 32 may have various cross sections such as triangular, square, pentagonal, ellipsoidal, or circular. It is preferred that center core 32 has a circular cross section, making center core 32 a cylinder. Page 22 of 56 232614 Upper boot flange 48 supports module top cap 18 which is threadedly engaged therewith. Spacer ring 54a surrounds upper membrane boot 44. [0128] FIG.5B is an expanded view of Detail 5B of FIG.5 showing the module bottom flange 16, threads 33 on the outer diameter of center core 32 as well as threads 35 on the inner diameter of bottom boot 46. Threads 33 and 35 serve to increase the surface area of the outer diameter of center core 32 and the inner diameter of receiver 36 to improve engagement with the potting material 23, which in one embodiment may be epoxy or other thermoplastic materials, to provide a vacuum seal to prevent leakage. [0129] Referring to Figures 5, 5A, 5B, the shell 12 is, in one embodiment, a single cylindrical tube made of a thermoplastic capable of withstanding operating temperatures varying from 5°C to 100°C. Shell 12 may alternatively comprise more than one component (not shown). Module top flange 14 provides for connection to a corresponding flange on a vapor collector header (not shown). The connection between the flanges is accomplished via interconnecting bolts 58 as seen in FIG.6. One or more seals, such as gaskets, (not shown) between the flanges provide a seal under vacuum. [0130] Referring to FIG.5B, in similar fashion, module bottom flange 16 provides for connection to module bottom cap 20. The module bottom cap 20 receives fiber membrane bundle 22 and therefore serves as bottom cap of the membrane module. [0131] The module bottom cap 20, may, in one embodiment, be manufactured from a single piece of thermoplastic. In one embodiment, module bottom cap 20 includes an industry standard 12” flange 24 having the same bolt pattern as the module bottom flange 16. In one embodiment, the bottom end incorporates the hydraulic connections to the cap including the feed water inlet 26, the concentrate water outlet 28, and a seepage outlet 30. The feed water inlet 26 is fluidly connected to the center core 32 of the fiber membrane bundle 22. [0132] Further referring to Figures 5 and 5B, the feed water inlet 26 is in one embodiment a standard 2” male “Camlock” connection type. A series of seals (not shown) ensures the hydraulic integrity at the interface point of the module bottom Page 23 of 56 232614 cap 20 with the ends 32a and 32b of center core 32 of the fiber membrane bundle 22. [0133] Liquid flowing out of the hollow fiber membranes 42 is collected in the module bottom cap 20 and directed to the concentrate outlet 28 of the connector, which in one embodiment is a 2” male “camlock” connection type. A series of seals 40b, 40c, 40d, ensures the hydraulic integrity at the interface point of the fiber membrane bundle 22 with the module bottom cap 20 and concentrate outlet 28. [0134] The seepage outlet 30 is at the module bottom cap 20 of the fiber membrane bundle 22. Any liquid that should pass through the membrane is collected and returned to a seepage tank (not shown) of the process via the seepage outlet 30, which in one embodiment is of the 1” male “camlock” connection type. [0135] Male “camlock” connections for feed water, concentrate and seepage correspond to female “camlock” connections which are typically by braided hose or rubber hose but may also be a hard-piped connection. [0136] The module bottom cap 20 comprises a receiver 36 for a fiber membrane bundle 22 having, one embodiment, an approximate diameter of 8”. The receiver 36 is designed to accommodate complete vacuum. Receiver 36 is at the center of the module bottom cap 20, and is, in one embodiment, a female connection region for the fiber bundle 20 which is approximately 150 mm in diameter. Central to the receiver for the fiber bundle is an end core receiver 38 for receiving a center core end connector 34 of fiber membrane bundle 22. [0137] As seen in FIG.5B, receiver 36 is equipped with two “O” ring seals 40c and 40d around its inner circumference. Stated differently, O-rings 40c and 40d fit into chamfers on the outer diameter of center core connector 34. These O-rings are designed to ensure that vacuum integrity and hydraulic integrity are maintained and that the fiber membrane bundle 22 is securely seated. A gasket 37 is provided to impart a vacuum seal the module bottom cap 20 to the module bottom flange 16. [0138] FIG.6 is an exploded view of the hollow fiber membrane bundle of FIG.5 in which a plurality of hollow fiber membranes 42, depicted collectively as fiber membrane bundle 22, is disposed between top and bottom membrane boots 44, 46. The ends 42a, 42b, of the hollow fiber membranes 42 are secured to the membrane boots 44, 46 by chemical bonding with a potting material 23. Potting material 23 may Page 24 of 56 232614 be a thermoplastic polymer that is used to secure the ends of the plurality of hollow fiber membranes 42 to the membrane boots 44, 46. Each membrane boot 44, 46 has a bundle flange 48 (top), 50 (bottom). Bundle flanges 48, 50 fit "inboard" of the membrane boots 44, 46. That is, upper bundle flange 48 fits to the bottom end of upper membrane boot 44, while lower bundle flange 50 fits to the top end of lower membrane boot 46. In line with the preceding sentence, supporting rods 52 (one or more, with four depicted in FIG.6), are secured at each end to the respective bundle flanges 48, 50 and provide structural support to (that is, they act to provide longitudinal tension to) the fiber membrane bundle 22. In one embodiment, each of the bundle flanges 48, 50 comprises two halves, for ease of assembly. It is seen that bundle flanges 48, 50 include two concentric rings of apertures 48a and 50a, to accommodate two sets of bolts (generally 58) for two different purposes. For example, the inner ring of apertures 48a defined in bundle flange 48 accommodates bolts 58a to attach bundle flange 48 "up" to upper membrane boot 44. The outer ring of apertures 48b defined in bundle flange 48 accommodates a different set of bolts 58b to attach bundle flange 50 "down" to supporting rods 52. [0139] Center core 32, best seen in Figures 5, 5B, runs up the center of the fiber membrane bundle 22. Referring to FIG.6, a center core connector 34 provides a fluid connection for feed water to enter center core 32 from the feed water inlet 26 of the module bottom cap 20. A module top cap 18 is sealingly attached to the top membrane boot 44. Center core 32 transmits feed water from inlet 26 of module bottom cap 20 to the module top cap 18 where it is distributed to the hollow fiber membranes 42 for return flow down the interior (lumen) (not shown) of the hollow fiber membranes 42. In some embodiments, the feed water may be provided to the exterior of the hollow fiber membranes 42. A spacer ring 54a disposed between the top bundle flange 48 and the module top cap 18 assists with engagement and sealing of module top cap 18. The inner surface of the spacer ring has a chamfer 39 at one edge to seat an O-ring 40a. Another spacer ring 54b assists engagement and sealing of the bottom membrane boot 46 with the module bottom cap 20, as seen in FIG.4. Projections 56 extending radially from the module top cap 18 are dimensioned to approach or abut the inner circumference of the module shell 12, thereby locating and supporting the membrane element in proper axial orientation and protecting the Page 25 of 56 232614 fiber membrane bundle 22 from malfunction or damage resulting from lateral movement within the shell 12. [0140] Flow of vapor around the membrane fibers 42 is influenced by the packing density of the fibers. The packing density of the fiber membrane bundle 22 is engineered for optimal performance for the intended application. Water vapor passing through the hollow fiber membranes 42 can exit the fiber membrane bundle 22 into space S between the outer circumference of the fiber membrane bundle 22 and the inner surface of the module shell 12 and is extracted under vacuum through a vapor header (not shown). [0141] As seen in FIG.6, the effective membrane length LE, as shown in FIG.4, is the length of a fiber bundle, between top membrane boot 44 and bottom membrane boot 46, which contributes to vapor production. Total membrane bundle length, LT, refers to the total length of a membrane bundle, including LE, the length of module bottom cap 20 including, in one embodiment, bundle inlet camlock connector 26, plus the length (LP) of two membrane boots 44, 46. In one embodiment, the distance LE is about 70 cm, and may be about 80 cm, about 90 cm, about 100 cm about 110 cm, 120 cm or other values in between. In one embodiment, the length LP is about 5 cm, about 10 cm, about 15, cm, about 20 cm, about 25 cm or other values in between. [0142] It has been determined that the performance of the seal between the potting material 23 and the center core 32 or between the potting material 23 and the membrane boots 54a, 54b can be greatly enhanced by a design in which end sections of the center core 32 are adapted for enhanced bonding with potting material 23. For example, US. App. Ser. No. 18/662,224 filed 13 May 2024 is referred to for disclosures relating to threads, apertures through threads, or porous thermoplastic for enhanced bonding with potting material. However, the entire document is incorporated by reference herein. to FIG 1, the feed solution is a solution containing a series of salts. Each salt has an individual solubility, but the entire matrix of salts and the interactions of salts define the saturation point of the entire solution. The system can be run, but is not limited to, in the following manners: using solubilities determined by experimentation, estimation, thermodynamics or trial and error. The Page 26 of 56 232614 mixture solubility can be estimated by using the solubility of the components in the mixture. Each component generally precipitates earlier than its individual solubility limit would suggest. The following equation can be used to give an estimate of the concentration at which the components will precipitate under predetermined conditions. The saturation point is calculated including all the constituents at the beginning, and recalculated as components are removed from the system: [0144] ∑ ( ) [0145] Component 1 is the least soluble, while nomponent n is the most soluble, while the rest are ranked in order of solubility. [0146] Csat,mix = Saturation Concentration of the mixture of dissolved solids [0147] Csat,n = Saturation Concentration of the individual dissolved solid [0148] xn = the mass fraction of the individual dissolved solid [0149] mn = the experimentally determined constant or function [0150] C = Cation [0151] ci = cation’s stoichiometric factor [0152] A = Anion [0153] ai = Anion’s stoichiometric factor [0154] (s) = Chemical Sate: Solid [0155] (aq) = Chemical State: Aqueous [0156] Ki = Equilibrium Constant for individual species [0157] Thermodynamics gives a rigorous process to determine the solubilities using the equations of state and equilibrium chemistry simultaneously. [0158] The equilibrium constants for each species of the mixture are defined by the Gibbs Free Energy of Reaction as shown in the following formula: [0159] G°i = Partial Molal standard state Gibbs Free Energy of Reaction [0160] R = Gas Law Constant (8.314 J/mole/K) [0161] T = Absolute Temperature [0162] Ki = Equilibrium Constant [0163] The mixture will be defined by its principal thermodynamic properties. Page 27 of 56 232614 [0164] Additionally, the rs) equations of state must be satisfied. Page 28 of 56 232614 Page 29 of 56 232614 Page 30 of 56 232614 Page 31 of 56 232614 Page 32 of 56 232614 [0165] One such arrangement of the unit operations is shown below, using KMX-VMD as the concentrator, a temperature-controlled tank as the crystallizer and Page 33 of 56 232614 a UF & filter press as the separator. The process proceeds to remove water, precipitate salts sequentially and produce a saturated solution of the most soluble species at processes end. [0166] Process Des VMD is a semi-batch unit consisting of a single ne area). Its design replicates that of the KMX on, feed is heated with a heating coil before enteri d is heated to 60-70°C and flows on the inside of t ows along the membrane, the water in the feed is converted to vapor which passes through the wall of the membrane and is condensed as “distilled water” (permeate). The remaining “cooled” feed (concentrate) is returned to the feed tank for reheating and recirculation back to the membrane. [0167] The process of recirculating the feed through the membrane and back to the feed tank continues until the desired water recovery level or salt concentration has been achieved. Each time the feed passes through the membrane, a percentage of the water is removed. Once the batch is complete, the concentrated solution is then removed from the feed tank, and the system is flushed with water to remove any residual salts prior to starting a new batch. [0168] Should excessive “seepage” occur during the concentration process, the membrane is flushed with a dilute acid solution, such as citric acid, to remove any deposits. Excessive seepage is typically associated with organic material in the feed. [0169] The concentrate, once removed from the feed tank is allowed to cool to room temperature at which point the low solubility salts precipitate out of solution. In the commercial system, precipitated salts will be recovered “in line” via a cooling loop and inline filtration. [0170] Referring to FIG 8, an overview 800 of the salt separation process of the disclosure is presented. The 200 liter feed sample, item 802, water was run on KMX’s lab scale VMD, 804. Step 1, 806, of vacuum membrane distillation (VMD) concentrates the feed sample to remove 70% of water resulting in NaCl removal, 808. Step 2 of VMD is further concentration, 810, which removes a total of 95% of water resulting in KCl recovery, 812, followed by recovery of LiCl and MgCl2, step Page 34 of 56 232614 816. The two concentration steps 806 and 810 result in 95% water recovery, 814, with less than 10 ppm total dissolved solids (TDS) remaining. [0171] As seen in FIGS.9-11, and 13F, the 200 liters of feed (the composition of which is seen in FIG.11) was processed in several batches. Each batch was concentrated to ~350,000-380,000 ppm TDS (see FIG.13F) and then cooled. At this point, because of its relatively low solubility in the combined salt mixture, NaCl began dropping out of solution. The initial three batches were cooled to below room temperature while the remaining three batches were cooled to room temperature and then below room temperature. As seen in FIGS 13A through 13F, the results showed that cooling below room temperature caused co-precipitation of the KCl along with the NaCl while cooling at room temperature resulted in only minor co-precipitation of KCl. [0172] As seen in FIG.9, it is seen that the 200 liters of feed sample 901 is split into four VMD feed batch tanks (902, 904, 906, and 908) each having a capacity of only 50 liters. Each 50 liter feed sample then flows into a respective VMD unit (912, 914, 916, and 918). Processing in each of the four VMD units results in recovered water 920 and concentrates 1-4 (922, 924, 926, 928), which all feed into tank 930 resulting in precipitated salt. Concentrates 1 and 2 (922, 924) are fed into a fifth VMD unit 933 to produce concentrate 5, 943, while concentrates 3 and 4 (926, 928) are fed into a sixth VMD unit 937, to produce a second quantity of recovered water 940 and concentrate 6, 947. Concentrates 5 and 6 are collected together to produce a final precipitated salt 950. [0173] Referring to FIG.10, the results of the six batch precipitation steps are shown schematically. Concentration takes place in VMD units 912, 914, 916, 918, 933 and 937 at 60°C. However other temperatures such as 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C or 90°C are possible. As noted in items 913, 915, 917, 919, 934 and 938, highly pure water is produced, from 16 to 30 kgs of water having low TDS, from 2 ppm to 26 ppm. Batch precipitation is undertaken at 0 to 20°C in steps 922, 924, 926, 928, 944 and 948 resulting in 3.9 to 9.7 kg of a salt mixture containing the proportions of NaCl and KCl shown in such steps. [0174] This sequence was repeated over 4 batches (50 liters each), until all the feed sample (200 liters) was completely processed. After removing 63% of the NaCl in the initial 4 batches, the remaining concentrates from the 4 batches was Page 35 of 56 232614 combined into 2 additional batches and run again in the VMD to remove additional NaCl. These last 2 batches were concentrated to ~380,000 ppm TDS and an additional 17% of the NaCl was removed for a total of 80% removal. In addition to NaCl, 64% of the KCl in the feed co-precipitated with the NaCl at “below” room temperature, whereas only 0.6% co-precipitated at room temperature. [0175] The trial was stopped at this point (due to a lack of feed volume), leaving behind a brine concentrate containing 20% KCl, 16% LiCl, 24% MgCl2 and 41% NaCl (Refer to Appendix 1, Table 2a). Had the six batches been concentrated at room temperature only, the final brine composition would have been 51% KCl, 16% LiCl, 24% MgCl2 and 10% NaCl, see FIG.13E, Table 3E. [0176] To confirm the ability to remove KCl from the KCl rich brine produced in step 1, the sample was heated to over 100°C for one hour, mimicking water removal in the VMD. As KCl has a lower solubility than MgCl2 & LiCl (34% vs 55%) once sufficient water is removed, it will drop out of solution ahead of the MgCl2 and LiCl when cooled to room temperature. The precipitate produced after water removal and cooling to room temperature contained 88% KCl. [0177] Referring to FIGS.15A through 15J, for each of the six batches, samples of the concentrate (supernatant), precipitant and permeate were analyzed to determine the purity levels of each of the precipitated salts and the recovered water. Also, following each step, a mass balance was completed to determine the % water recovered and overall flux rate. [0178] The mass balance showed that 83% of the water in the original feed sample was recovered at a weighted average purity level of 9 ppm TDS as seen in FIGS.10 and 14. [0179] Energy Consumption and Commercial System Design. Because of the nature of the trial (multiple concentrations followed by multiple salt separations) and the size of the lab unit, it was impractical to calculate the energy consumed during the trial. [0180] Referring to FIG.12, Table 2, and based a mobile pilot unit trial using six commercial scale membranes, and calculations based on experience with mechanical vapor compression and heat pumps, it is believed, while not being bound by theory, the estimated energy consumption values presented therein for commercial VMD units are reasonable. Page 36 of 56 232614 [0181] While not being bound by theory, based on these results, it is believed that the KMX VMD technology is a viable option for concentration of KCl and production of high-quality water from a KCl-rich stream. [0182] As indicated above, a higher level of KCl co-precipitation occurred below room temperature because the solubility of KCl is lower than NaCl at lower temperatures. As seen in FIGS.15B and 15C, batches 1 and 2 were precipitated at room temperature (about 20 or 22°C) then below room temperature (about –18 or – 20°C) whereas batches 4 – 6 were precipitated only below room temperature (about –18 or –20°C). [0183] Referring to Figure 16, a ternary phase diagram among NaCl, KCl and water, there are 4 distinct regions on the phase diagram: the liquid region, (upper portion which includes the H2O corner) where all the salts are dissolved; the liquid + KCl(s) region (left side shaded portion), where there is a mixture of precipitated potassium chloride and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride. Another region is the Liquid + NaCl(s) Region (right side shaded portion) where there is a mixture of precipitated sodium chloride and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride, and the last region the liquid + Fm3m + KCl(s) region (lower unshaded portion) where there is a mixture of precipitated potassium chloride, precipitated Fm3m and a liquid phase containing water, dissolved potassium chloride and dissolved sodium chloride. Fm3m is a cubic salt in which sodium, potassium and chloride form a mixed matrix salt. The situation for this mixture is more complicated as it contains significant amounts of lithium and magnesium, and an array of other salts in smaller amounts. In order to get pure sodium chloride to precipitate the sample must fall on the right-hand side of the triangle, but as sodium chloride is removed it pushes the sample towards the left, inevitably moving into the mixed salt region. [0184] Figure 17 depicts the relation between solubility and temperature for the major components of the disclosed samples being separated. At elevated temperatures the solubility order from low to high is sodium chloride, potassium chloride, magnesium chloride then lithium chloride. This is the order in which the salts are expected to precipitate as water is removed. The slope of the solubility curves allows the choice of operating conditions which make producing a Page 37 of 56 232614 supersaturated solution in the VMD relative to the crystallization operating conditions. A key point to observe is that the solubility curves of sodium chloride and potassium chloride cross at about 25°C. This will be further discussed in relation to the crystallization and recrystallization. [0185] As seen in FIGS.15A through 15J, the process was performed in six concentration steps, in each step the sample was concentrated until the sample was ready for crystallization. The endpoint of each concentration step was determined by the system’s inability to recirculate the supersaturated solution through the membrane bundle or processing logistics. [0186] Additionally, crystals were inevitably trapped in the system. At times the system needed to be disassembled to remove and clean the crystals. The filter bag, the module top cap, module bottom cap, pump head, tank and tubing were all locations in which crystals formed. It is believed that a gravity drain and clean-in- place system will be able to recover precipitated solids. The trapped crystals were not easily transferred to the crystallization tanks, so they were sometimes lost, making the mass balance difficult to close, so a necessary assumption was that no solids were lost. The solids were accounted for as either being in the solution or in the precipitate. The mass of solids recovered was only part of the solids produced. [0187] In FIG. 18 (Solid Concentration vs. Permeate Volume) and FIG. 19 (Table 6), the total solids equivalent (TS-eq) is the total solids relative to the liquid volume without regard to whether it is a precipitated solid or dissolved solid. Its trend upward is as expected because the mass of solids is constant while the volume of liquid is decreasing. One data point, at permeate volume 67 liters, appears to be higher than expected, and while not being bound by theory, is believed to be an inaccuracy in the sampling or determination of volume or concentration. This may account for the subsequent dip in values at permeate volumes of 74 and 87 liters. Additionally, some of the precipitated solids may be recovered in a concentration round later than when it was initially precipitated. The sample was concentrated well beyond saturation, ultimately approaching three times the sodium chloride saturation point. Looking at this on a mass basis rather than a concentration basis shows the same. [0188] From the mass basis analysis, the mass of the total precipitate is constantly increasing. The produced slurry is super saturated and allows the removal Page 38 of 56 232614 of salt based on the difference of mass contained in the slurry and the TDS of the concentrate at each stage relative to the saturation value at the precipitation conditions. [0189] The precipitation took place in 5-gallon buckets first left to cool to room temperature and then moved to a chest freezer. Better temperature control and selectivity would be beneficial to the precipitation process. The precipitates were recovered using a simple decanting followed by coarse filtration - 3 micron paper filter in a Buchner funnel. Some of the crystals were smaller than this size cut off and were believed to have been returned to a subsequent VMD concentration stage. The crystals at each stage were analysed for composition, the results are shown in FIG. 22, Table 8, in which "F" means freezing (about -18 or -20°C) and "RT" means room temperature, (about +20 or +22°C). [0190] Given the make-up of the feed, concentrates and crystals, the results from the outside lab are used to calculate how much of each salt is in each stage of the process. The four major constituents (NaCl, KCl, CaCl2, and LiCl) are tracked as the remaining constituents are in trace quantities. In the first two concentration rounds the precipitant is almost entirely made up of sodium chloride. This indicates that the solution was in the right-hand region of the triangular phase diagram of FIG. 16. Starting in the third batch of crystallization co-precipitation of potassium chloride and sodium chloride decreased. [0191] To further analyze the individual precipitants, it is necessary to smooth the precipitation curve using a curve fit. As seen in FIG. 23, the curve fit closely represents the data with a near unity R2 value (0.99). The data for FIG.23 are shown in FIG. 24. From this the total mass of each precipitation stage and the mass produced at each stage can be calculated. Then using the mass fraction of the room temperature and freezer temperature precipitation the mass of each precipitation can be calculated for each temperature. Thus, the mass of precipitants can be tracked throughout the experiment. Additionally, the relative mass of precipitation at the two temperatures is also seen. The advantage of the lower temperature is the absolute mass of the precipitation is much larger than that of the higher temperature. [0192] Figure 25 shows the relation of solids by mass vs. permeate volume with total precipitate produced at -18°C and +22°C. Initially sodium chloride can be selectively precipitated at -18°C. Using the lower temperature ensures maximum Page 39 of 56 232614 precipitation in the first two rounds of concentration. This indicates that the sample is in the right-hand part of the triangle at any temperature. As the potassium chloride concentration increases, higher temperature precipitation is required to keep the sample in the right-hand part of the phase diagram of FIG.16. By properly selecting the crystallization temperature at different concentrations the precipitation can be controlled to yield relatively pure crystals. Additionally, the magnesium chloride and lithium chloride remained in solution. [0193] The separation technique used recovered the crystals as a wet mass of crystals, commonly referred to as a wet cake. A sample of wet cake was dried in an oven, and it was determined that the volatile content was 9.13%. This means that the wet cake had 9.13% of water that was saturated with salts. A mass balance of the cake was determined, and it indicates that essentially all of the lithium chloride and magnesium chloride in the wet cake were associated with the liquid composition trapped in the cake. While not being bound by theory, it is believed that a centrifuge or filter press would minimize the dissolved solids trapped in the filter cake. This would eliminate the contamination seen in these results. [0194] The precipitation by mass relation in FIGS. 26 and 27 shows the selectivity of the process to first produce pure sodium chloride crystals and then selection of the crystallization process conditions to separate the potassium chloride from the sodium chloride. The final round of precipitation produced 98.6% pure sodium chloride at 22°C and 77.6% pure potassium chloride at -18°C. If required the potassium chloride purity could be boosted by recrystallization. FIG. 27 shows the beginning of the chromatographic like separation of salts using the VMD- crystallization process. [0195] When the separation of sodium chloride and potassium chloride is of interest, recrystallization is demonstrated as a means of post-VMD processing to show high purity potassium chloride could be recovered. In the solubility curves the intersection of the potassium chloride and sodium chloride is shown. This allows the temperature to be chosen in such a way that either sodium chloride or potassium chloride is preferentially solubilized. At high temperatures potassium chloride is more soluble than sodium chloride, so when the mixed crystals are dissolved in an amount of water insufficient to fully dissolve the sample, potassium chloride is enriched in the solution and sodium chloride is enriched in the precipitant. Then when the Page 40 of 56 232614 recrystallization fluid is moved to the freezer, sodium chloride is more soluble than potassium chloride, so the precipitant is enriched in potassium chloride. This allowed the crystals that were 34% potassium chloride to be boosted to 87.5% potassium chloride. Using the VMD to reconcentrate the recrystallization fluid would allow for the liquid and solids to be recycled or recovered at the appropriate stage in the process if necessary. [0196] Results of the Experimentation. As seen in FIG 18 (Solids Concentration vs. Permeate Volume) and related FIG. 19 (Table 6) the experiment starts with a sample near saturation (347,491 ppm), 64% of the water (231-84/231) was removed and 65% (52.1/80.3) of the dissolved solids were precipitated as seen in FIG.21. Sodium chloride was recovered at up to 98.9% purity. Potassium chloride was recovered at up to 87.5% purity. Better than RO quality water was recovered throughout the process. The beginning of near-chromatographic separation of salts was demonstrated. Selective precipitation was demonstrated for VMD concentrates. [0197] The VMD portion is the heart of VMD-ICR process. In VMD there are three stages based on temperature: A) the hot feed water circulation stage; B) the produced vapor stage and C) the vapor condensation stage at a temperature less than the vapor production stage. [0198] In various embodiments, the VMD units disclosed herein may be operated at selected temperatures, pressures and flow rates. For example, the VMD unit may be operated at 0-90°C, 10-80°C, 20-70°C, 30-60°C, 40-50°C, 50-70°C or 65-70°C. The VMD unit may be operated at pressures such as 1-1000 mBar, 5-500 mBar, 10-200 mBar, or other values such as 70, 80, 90, 100, 110, 120, 130, 140, 150 mBar and other values between 1 and 1000 mBar. It is envisioned that a VMD unit of the disclosure may be operated as suitable flow rates in units of lmh (liters per square meter per hour) of 1-50, 2-40, 3-30, 4-20, or values such as 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19 lmh. [0199] The feed circulation water can operate within the range of about 35°C to about 75°C, or about 40°C to 70°C, or about 45°C to about 65°C. The feed water circulates in a loop starting from feed water tank and then it goes into the membrane modules where it is partially concentrated by losing pure water as vapor. [0200] The produced vapor temperature is usually about 1°C to about 10°C, or about 2 °C to about 9 °C, or about 3 °C to about 8 °C, or about 4°C to about 7°C or Page 41 of 56 232614 about 5°C or about 6°C, lower than feed water temperature. The cold/cooler portion of VMD includes the condensers where produced vapor condensed into near pure water. The temperature of these condensers is a few degrees lower than that of the produced vapor, for example in the cooling loop a cold liquid with a temperature of around 5°C , 10°C or 15°C (or values therebetween) can be used (in the pilot plant the produced vapor was 45-52° C and the cooling liquid was 4°C). [0201] In a VMD system, membrane modules work in a low pressure which is limited to a total water entry pressure (WEP) of about 24 psi, more or less depending on the hydrophobic membrane used. The water pressure inside a membrane module is limited to less than about 10 psi. Vacuum levels typically used in VMD are about - 13 to about -14 psi, of which 99.9% of that value is theoretically possible with VMD, however the cost of maintaining such a high level vacuum is often not economically justified. [0202] VMD can have one or more membrane modules, each membrane module has a membrane bundle with hollow fiber membrane with a surface area of around, about 0.1 to 1 m2, 1 to about 20 m2, such as about 5 to 15 m2 or about 7-13 m2 or about 10m2. The membrane module may operate in an inside-out mode of operation wherein liquid goes inside the lumens of fibers while the vapor is produced in the shell and is collected through vapor collectors which are connected to vapor condensers. The opposite configuration is also possible. [0203] Condensers: The vapor condensers usually are shell and tube heat exchangers operate via a cooling liquid (cooled by a chiller) which is circulated within the cooling loop inside the tube to adsorb the heat and condense the vapor inside the shell. [0204] Seepage Vessel: each membrane module can produce some seepage which is collected into the seepage vessel; although some of the seepage may be condensed vapor inside the shell soon after operation is begun and before modules are up to operating temperature. This vessel is equipped with level detectors and when required, the collected seepage is pumped back into the feed tank by the seepage pump. [0205] Permeate vessel: The VMD produced vapor, which, after being condensed and converted into liquid water, is collected inside the permeate vessel, Page 42 of 56 232614 which is equipped with level controls. This permeate is a very high-quality water and when required, will be pumped to the permeate storage tanks. [0206] Vacuum, a vacuum pump is used to establish the desired vacuum level. The vacuum pump is designed to produce the vacuum at the beginning of the process as well as to maintain the vacuum during the process. [0207] Heating: the heating heat exchanger is used to head the feed water to desired temperature for example in the range of about 40°C to about 75°C. The source of heat can be different from renewable energy sources to available waste energy, electricity, as well as legacy energy sources. If required the VMD process can be integrated with energy recovery units such as heat pump (HP) and mechanical vapor compression (MVC). [0208] In VMD, a first feed tank whose contents are concentrated to near saturation, where one will be in operation and will concentrate the least soluble salt to near saturation, then a fresh batch of the same feed will be charged to the VMD feed tank. The solution from feed tank with saturated salt solution will be sent to a crystallization tank where it is cooled to accelerate crystallization. In the crystallization tank the larger and heavier crystals will precipitate and separate. The supernatant of the crystallization tank with micro crystals will be sent to ultrafiltration (UF) where small crystals will be separated in the UF concentrate while the UF retentate (permeate) will be sent to the feed tank after it is heated to a desired temperature (depending on the solubility of remaining salts) with a heat exchanger. The UF concentrate will be sent back to the crystallization tank. The solid crystals will be sent to a solid handling process such a filter press to remove excess liquid which may contain dissolved solids therein. [0209] Crystallization Reactor. When the solution in the feed tank reaches a desired concentration, the solution will be sent to the crystallization tank. This is a temperature-controlled tank such as a double jacket tank to let the temperature of the solution to be controlled within the desired range. The temperature of this tank will be independent of the concentrator and controlled at a temperature to allow crystallization. [0210] The VMD-ICR can also be designed without a crystallization tank meaning the size of the crystals and their separation will be managed within the feed Page 43 of 56 232614 tank and a separation unit such as UF or other filtration system (microfiltration, nanofiltration, hydrocyclone). [0211] Ultrafiltration (UF) system. UF may be used as a separation unit. The UF molecular cutoff (about 100,000 daltons, or in some cases up to about 250,000 daltons) is chosen to be very tight to let only dissolved solids and macromolecule to pass through and therefore all particulates including micro crystals will be separated. The A separation unit with a molecular weight cut-off of 100,000 daltons should have a 90% rejection rate of dissolved materials with a molecular weight greater than 100,000 Daltons. The UF membrane may include ceramic or organic materials. Ceramic membranes can be used at high pressures and temperatures (such as 80, 90, 100 °C) while organic membranes such as paper, cellulose acetate, PVDF, polysulfide, PTFE, and polymeric membranes are typically operated in the range of 10-40°C. The UF system is equipped with a clean in place (CIP) system for cleaning of the UF membrane when it is required. [0212] A process for salt crystallization and separation of a concentrate from a concentrator includes when the salt concentrator operates at or above saturation where the process flow is intake to concentration/VMD, to crystallization to separation. [0213] An alternate mode of operation is similar to the operation mode where VMD operates below saturation. In this mode of operation VMD produces crystals beyond saturation which can be removed by a separation process like UF prior to entering the crystallization tank. Note that a sample at or above saturation can also be run in the order concentration, separation, then crystallization. [0214] In another major embodiment of the invention, a process of concentrating and removing salts, in particular, lithium salts, from an input stream is set forth below. [0215] The KMX pilot and laboratory scale VMD’s are semi-batch units, each consisting of a single membrane module. The pilot unit is equipped with a third generation commercial sized module, while the lab unit has lab scale module of the same design. [0216] During operation, feed is heated to 60°C before entering the membrane module. The heated feed flows on the inside of the hollow fiber membrane fibers. As the feed flows along the membrane, the water in the feed is converted to vapor Page 44 of 56 232614 which passes through the wall of the membrane and is condensed as “distilled water” (permeate). The remaining “cooled” feed (concentrate) is returned to the feed tank for reheating and recirculation back to the membrane. [0217] The process of recirculating the feed through the membrane and back to the feed tank continues until the desired water recovery level or salt concentration has been achieved. Each time the feed passes through the membrane, a percentage of the water is removed. Once the batch is complete, the concentrated solution is then removed from the feed tank, and the system is flushed with water to remove any residual salts prior to starting a new batch. [0218] The concentrate, once removed from the feed tank is allowed to cool to room temperature at which point the low solubility salts precipitate out of solution. The remaining concentrate is put back in the VMD feed tank and the process repeated. In a commercial system, precipitated salts will be recovered “in line” via a cooling loop and inline filtration. [0219] Phase 2 [0220] A brine that was processed through reverse osmosis and was not the result of direct lithium extraction (non-DLE post RO) was processed at the KMX Technologies lab to concentrate and recover Lithium Chloride (LiCl) from the brine using KMX’s Vacuum Membrane Distillation (VMD) system. The brine was composed of various salts, of which LiCl represented 4% by weight (a concentration of about 1,500 ppm) - see FIGS 28, 29A, and 29. The trial demonstrated that KMX’s Vacuum Membrane Distillation (VMD) technology is effective to concentrate and recover high grade LiCl from this stream at a concentration of about 200,000 ppm. [0221] Evaluation of the technology consisted of two stages. Stage 1 – processing of an 810-liter sample of naturally occurring Lithium brine using a single membrane pilot system and Stage 2 – processing a 200-liter sample of synthetic brine using KMX’s Lab scale unit. The pilot unit was used to remove the bulk of the water from the brine, after which the lab unit was used to concentrate the LiCl. The synthetic brine in the lab scale trial was made to the same composition as the concentrated brine from Phase 1. [0222] In Phase 1 of the trial 81% of the water in the sample was removed (See Figure 29A, Table 11) and the brine was concentrated from about 46,000 to about 205,000 ppm, a concentration factor of about 4.8. The LiCl in the sample was Page 45 of 56 232614 concentrated from about 1,500 ppm to about 11,800 ppm, the latter of which was the feed into the lab scale VMD. Because of contaminants in the sample (silica and surfactants), and their potential impact on membrane performance, it was decided at the end of Phase 1 to switch to a synthetic brine (free of contaminants) for Phase 2, such synthetic brine containing the same concentrations of the various salts obtained at the end of Phase 1. [0223] As seen in FIG.28, in Phase 2 of the trial, 93% of the water in the feed was removed for a total water recovery of 98% from the original 810-liter sample. Also in Phase 2, as seen in FIGS.29B and 30, the LiCl was concentrated from about 11,800 to about 235,000 ppm and the NaCl reduced from about 233,000 to about 8,400 ppm (90 wt% to 2.5 wt% of total salt). At the end of the trial, LiCl represented about 70 wt% of the total salt in the concentrate with CaCl2 at 25% of total salt. The trial was stopped at this point as insufficient volume remained (15 liters) to continue running. A future trial may start with a larger volume which will allow greater concentration and removal of CaCl2 from the stream, leaving a higher purity level of LiCl. An alternative to this would be to remove the CaCl2 before the reverse osmosis step. This would reduce the CaCl2 in the final concentrate, thereby increasing the purity level of the LiCl. [0224] The process used to remove the non-Lithium salts was one of concentrating to the saturation point of each salt, followed by cooling and precipitation of the salt. Because of its relatively low solubility in the combined mixture, NaCl dropped out of solution first, followed by KCl. A final concentration of 235,000 ppm LiCl was achieved over 26 rounds of precipitation, with 2-5 kgs of non- Lithium salts removed in each round. Some co-precipitation of salts also occurred during the process including LiCl. Lab results show that about 5% of the LiCl co- precipitated with the non-Lithium salts. This co-precipitated LiCl is dissolved in the liquid portion of the precipitant and, without being bound by theory, in a commercial process, could be recovered using a centrifuge and fed back into the VMD. In a commercial process, the VMD system will be designed such that the non-Lithium salts will be removed as they are precipitated out of solution. This will significantly reduce the time required to concentrate the LiCl and remove the non-Lithium salts. [0225] Both the pilot and lab scale VMDs ran well during the entire trial with only flushing of the membranes between rounds of salt separation (with permeate Page 46 of 56 232614 water) to remove any salt buildup. Membrane flux was reduced as expected in the salt separation portion of the trial due to the high salinity (over 300,000 ppm TDS) of the salts in the feed. No membrane “wetting” and minimal seepage levels were observed during the trial indicating a very robust membrane. [0226] In detail, referring to FIG.28, a salt separation process 1100 of an embodiment of the disclosure is presented. The 810 liter feed sample, item 1102, having an LiCl concentration of 1500 ppm was first heated to 60°C before passing through the membrane run on KMX’s pilot scale VMD 1104 wherein 82% of water was recovered (1110), and the LiCl concentration is increased to about 11,800 ppm and TDS about 250,000 ppm. Next the feed sample is run on KMX's lab scale VMD 1106 to recover 93% of water in the second stage, (1112), bringing the total water removal to 98%. Further, after steps 1110 and 1112, the salt removal shown in Item 1108 is 95% of NaCl, 96% of KCl and 88% of CaCl2. Further, after processing by the pilot scale VMD 1104 and lab scale VMD 1106, the concentration of LiCl is raised to 235,000 ppm (1114) lab scale VMD, 804. Step 1, 806, of vacuum membrane distillation (VMD) concentrates the feed sample to remove 70% of water resulting in NaCl removal, 808. Step 2 of VMD is further concentration, 810, which removes a total of 95% of water resulting in KCl recovery, 812, followed by recovery of LiCl and MgCl2. The two concentration steps 806 and 810 result in 95% water recovery, item 814, with less than 10 ppm total dissolved solids (TDS) remaining. At that point, the concentrated feed was removed from the feed tank. The analysis of the concentrate and permeate are shown in FIGS.29A and 29B (Tables 11 and 12). [0227] A synthetic brine (200 liters) produced to have the same composition as the final Pilot unit concentrate (see FIG 29B, Table 12) was further concentrated in the Lab unit to about 300,000 ppm TDS at which point, the NaCl in the sample began to drop out of solution. The VMD was stopped at this point, the concentrate cooled and additional NaCl precipitated out. Once the precipitation was complete, the remaining concentrate was re-heated, returned to the VMD and the process repeated until 95% of the NaCl, 96% of the KCl and 88% of the CaCl2 were removed. In total, 26 rounds of precipitation were required to remove the non-lithium salts. [0228] For each of 26 rounds of precipitation (See FIGS. 30-33), samples of the concentrate and precipitant were analyzed. Also, following each round, a mass Page 47 of 56 232614 balance was completed. The mass balance showed that 98% of the water in the original 810-liter sample was recovered at a TDS of <10ppm. The mass balance also showed that 95% of the LiCl remained at the end of the trial with 5% co-precipitating with the non-lithium salts. The final product after 26 rounds contained 2.5% NaCl, 4% KCl, 25% CaCl2 and 69% LiCl. [0229] Based on trial process data and analytical results, the KMX VMD successfully concentrated a non-direct lithium extraction/Post RO Lithium brine to 200,000 ppm. The trial also demonstrated the recovery of 95% of the LiCl Lithium in the original sample at about a 70% purity level (FIG.31). While not being bound by theory, it is believed that by starting with a larger sample volume in future trials, the process could be continued to remove additional non-Lithium salts and deliver an even higher LiCl purity level. It is also believed that the 5% of LiCl that co- precipitated with the non-Lithium salts can be recovered using a centrifuge. [0230] Finally, the trial confirmed the robustness of the Generation 3 KMX membrane at high salinity levels (up to 380,000 ppm TDS), with no “wetting” and very little seepage. The trial also demonstrated the ability of the membrane to recover very high-quality water (<10 TDS) for re-use, recovering 98% of the water from the initial feed. [0231] Without being bound by theory, based on these results, it is believed that the KMX VMD technology is a very viable option for concentration of a non- DLE/Post RO stream and recovery of high quality LiCl and water from the stream. [0232] In this study a sample with low lithium concentration (about 11,800 ppm) was subjected to three steps of treatment using RO and two stages of vacuum membrane distillation in order to reach over 200,000 ppm of lithium chloride. [0233] Step 1. Using a conventional RO the samples were treated to a TDS concentration level of about 260,000 ppm of which about 235,000 ppm was lithium chloride. [0234] Step 2. In first stage of VMD application the RO concentrate of step 1 was processed to a lithium concentration of about 11,800 ppm. [0235] Step 3. In the second stage of VMD, the final concentrate of step 1 of VMD was processed in 26 sequential rounds of operation: concentration, crystallization and separation until a LiCl concentration of over 235,000ppm (FIG.28; FIG 36, Table 1368.8% of 341981 ppm total final concentrate) was obtained while Page 48 of 56 232614 most of the NaCl was separated, leaving only about 8400 ppm in the total final concentrate. [0236] Experimental Procedure [0237] A low lithium concentration sample initially from a geologic source was pretreated with an RO to boost its initial concentration to the limits of conventional RO. Then, in previous work, this brine sample was concentrated using KMX VMD to near saturation of dominant salt which was NaCl using our standard concentrations methods. In the second round of VMD operation an artificial brine sample was made to match these end point specifications of the first round of VMD and used as the feed for this set of experiments. The goal of these experiments was to increase the Lithium Chloride concentration to a commercially viable value of over 200,000 ppm and enrich it to be the dominant component of the mixture. Both goals were achieved. [0238] The Feed sample was processed through 26 rounds of Total Brine Extraction (TBE). Each round consisted of 3 steps: a) Concentration, b) Crystallization, and c) Separation. [0239] Concentration step. Each concentration step consisted of running first the feed, and subsequently the concentrated liquid post separation from the previous round, in the VMD until the sample was saturated and could not be concentrated any further due to produced crystals within the system that blocked the fibers. The VMD was operated at nominally 70°C, 120 mBar and 12.7 lmh (liters per square meter per hour). The concentration step produced a saturated solution and permeate at lower than 10 ppm (25 of 26 times) and one at 50 ppm. [0240] Crystallization step. The saturated solution was transferred to the crystallizer and cooled in the freezer promoting the formation of crystals. [0241] Separation step. The Separation was achieved using decantation, vacuum filtration and ultrafiltration. Decantation separated settled solids and most of the saturated solution. The vacuum filtration separated the settled solids from the free saturated solution associated with the solids. The filtered liquid and the decanted liquid were then combined and run through an ultra-filtration unit separating the remaining suspended solids from the saturated liquid. This clarified saturated solution was then used as the feed for the next round of Total Brine Page 49 of 56 232614 Extraction. These three steps were repeated though all 26 rounds each time concentrating and enriching the Lithium Chloride in the saturated solution. [0242] At the beginning of the VMD process the Lithium Chloride concentration was about 1,800 ppm and represented 4.5% of the dissolved solids. By the end of VMD process the Lithium Chloride was 235,000 ppm and represented 70% of the dissolved solids. This represents a 20-fold increase in concentration of LiCl and a 95% removal of high purity water. Additionally, through Round 17, >99% pure sodium chloride was collected as precipitation. The recovered precipitation was collected as a wet cake. Drying tests indicated that the wet cake included 10-15% liquid trapped in it and thus accounted for the profile of other salts associated with the precipitation. Referring to FIGS 32 and 33, it is seen that after Round 17 the sodium chloride content decreased, and the potassium chloride content increased. [0243] The continuation of these rounds of experiments according to the modeling can results in LiCl salt with purity of about 97% while other salts also will be separated. [0244] As seen in FIGS. 34 and 35, this experiment was repeated in simulation with the equilibrium points calculated using OLI software. Each Concentration step was run to the equilibrium of the saturated solution under VMD conditions. The permeate was calculated via the difference of the mass of water from the beginning to the end of the concentration step. Then using a mass balance, the concentration of the material being fed to the crystallizer could be calculated. Next, the equilibrium of the solution under the crystallizer conditions could be calculated, determining the mass and nature of the precipitation. Again, using a mass balance, the precipitated material could be removed from the mixture and determine the content of the clarified concentrate ready to be moved to the next round. The simulated results show trends similar to those in the experimental results. [0245] Figure 36 provides an overview of initial feed salt quantities and TDS in the pilot scale trial, and parts 1 and 2 of the lab trial as well as the final concentrate salt quantities and TDS of the final concentrate from part 2 of the lab trial. It is seen that the total dissolved solids is increased from about 4.62 wt% to about 34.2 wt%. In the final concentrate, 68.8% of the total salt contents is LiCl. Page 50 of 56 232614 [0246] Figure 37 shows the total water removed in the pilot scale trial and parts 1 and 2 of the lab trial, discussed in the preceding paragraph. [0247] Figure 38 depicts mass and percentage of salts removed from the 26 rounds of processing in the KMX Lab VMD unit indicated for Rounds 1-13 collectively and rounds 14-26 collectively. Inasmuch as relatively low amounts of LiCl, KCl and CaCl2 are recovered through the 26 rounds of VMD processing, such salts remain in solution and are recovered by centrifuge and fed back into the VMD. [0248] An embodiment is an implementation or example of the present disclosure. Reference in the specification to “an embodiment,” “one embodiment,” “some embodiments,” “one particular embodiment,” “an exemplary embodiment,” or “other embodiments,” or the like, means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the invention. The various appearances “an embodiment,” “one embodiment,” “some embodiments,” “one particular embodiment,” “an exemplary embodiment,” or “other embodiments,” or the like, are not necessarily all referring to the same embodiments. [0249] If this specification states a component, feature, structure, or characteristic “may”, “might”, or “could” be included, that particular component, feature, structure, or characteristic is not required to be included. If the specification or claim refers to “a” or “an” element, that does not mean there is only one of the element. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element. [0250] As used herein in the specification and claims, including as used in the examples and unless otherwise expressly specified, all numbers may be read as if prefaced by the word “about” or “approximately,” even if the term does not expressly appear. The phrase “about” or “approximately” may be used when describing magnitude and/or position to indicate that the value and/or position described is within a reasonable expected range of values and/or positions. For example, a numeric value may have a value that is +/−0.1% of the stated value (or range of values), +/−1% of the stated value (or range of values), +/−2% of the stated value (or range of values), +/−5% of the stated value (or range of values), +/−10% of the stated value (or range of values), etc. Any numerical range recited herein is intended to include all sub-ranges subsumed therein. Page 51 of 56 232614 [0251] Additionally, the method of performing the present disclosure may occur in a sequence different than those described herein. Accordingly, no sequence of the method should be read as a limitation unless explicitly stated. It is recognizable that performing some of the steps of the method in a different order could achieve a similar result. [0252] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open- ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures. [0253] In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. [0254] Moreover, the description and illustration of various embodiments of the disclosure are examples and the disclosure is not limited to the exact details shown or described. Page 52 of 56 performing some of the steps of the method in a different order could achieve a similar result.
[0252] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open- ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures.
[0253] In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
[0254] Moreover, the description and illustration of various embodiments of the disclosure are examples and the disclosure is not limited to the exact details shown or described.

Claims

232614 CLAIMS 1. A process of separating at least one salt from a liquid stream comprising the at least one salt, the process comprising: providing a liquid stream comprising the at least one salt; concentrating the liquid stream to at least near saturation; crystallizing the at least one salt out of the liquid stream to produce a slurry comprising crystals of the at least one salt; and separating the salt crystals from the salt slurry. 2. The process of claim 1, wherein concentrating the liquid feed stream comprises treating the liquid stream with vacuum membrane distillation. 3. The process of claim 1 or 2, wherein crystallizing the at least one salt comprises adjusting the temperature of the liquid stream and/or of the crystallizer until at least a portion of a least soluble salt precipitates out of solution. 4. The process of any of claims 1-3, wherein separating salt crystals from the salt slurry comprises at least one selected from coarse filtration, hydrocyclone filtration, ultrafiltration, microfiltration and nanofiltration. 5. The process of any of claims 2-4, wherein at least one hydrophobic porous membrane is used for vacuum membrane distillation. 6. The process of claim 5, wherein the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 m2, or about 1 to about 20 m2, preferably about 5 to 15 m2, more preferably about 7 to 13 m2 and still more preferably about 10m2. 7. The process of claims 5 or 6, wherein the hydrophobic porous membrane has a pore size of less than 0.5 micron, preferably about 0.05 micron to about 0.45 micron, preferably about 0.2 micron to about 0.45 micron, preferably about 0.25 micron to about 0.45 micron. 8. The process of claim 1, wherein near saturation is defined as at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, at least 99.5%, or at least 99.9% of the saturation concentration of at least one salt, or other values in between the foregoing. Page 53 of 56 232614 9. The process of claim 1, wherein near saturation is defined as a concentration greater than the saturation concentration obtainable by the crystallizer. 10. A process of purifying a feed stream containing water, comprising a. providing a feed stream to at least one crystallizer to provide a more concentrated output stream; b. directing at least a first portion of the concentrator output stream to a crystallizer which will output saturation solution and salt crystals; c. directing a second portion of the concentrator output stream to a separator; d. directing a third portion of the concentrator output stream to a seepage tank to form seepage; e. directing the seepage to the input stream; f. directing at least a first portion from the concentrator to a permeate vessel to form a permeate; g. directing at least a second portion of the condensed concentrated output through a filter to provide a filter cake and a permeate; h. directing at least a portion of the permeate to the feed stream; and i. wherein at least a portion of the filter cake comprises salt crystals. 11. A system for removing salts from a liquid stream, comprising: a concentrator configured to concentrate at least one salt to at least near the saturation point of the at least one salt; a crystallizer configured to crystallize at least one salt; and, a separator configured to separate crystals of the at least one salt from the liquid stream. 12. The system of claim 11, wherein the concentrator comprises: a vacuum membrane distillation unit comprising at least one porous hollow fiber membrane. 13. The system any of claims 11 or 12, wherein the crystallizer comprises: at least one condenser. 14. The system of any of claims 11-13, wherein the separator comprises: at least one selected from a coarse filtration unit, a hydrocyclone filtration unit, an ultrafiltration unit, a microfiltration unit and a nanofiltration unit. Page 54 of 56 232614 15. The system of any of claims 12-14, wherein the at least one porous hollow fiber membrane has a surface area of about 0.1 to about 1 m2, or about 1 to about 20 m2, preferably about 5 to 15 m2, more preferably about 7 to 13 m2 and still more preferably about 10m2. 16. The system of any of claims 12-15, wherein the at least one porous hollow fiber membrane has an average pore diameter of 0.5 micron, preferably about 0.05 micron to about 0.45 micron, more preferably about 0.2 micron to about 0.45 micron, and still more preferably about 0.25 micron to about 0.45 micron. 17. The system of any of claims 13-16, wherein the at least one condenser comprises or is selected from: shell-and-tube heat exchanger, plate-and- frame heat exchanger, and a chiller including a cooling loop. 18. The system of claim 17, wherein the system is configured to operate in an inside-out mode of operation wherein a liquid feed stream enters lumens of hollow fibers while a vapor is produced in a shell and is collected through vapor collectors which are connected to vapor condensers. 19. The system of any of claims 11-18, further comprising at least one of a seepage vessel and a permeate vessel. 20. The system of any of claims 11-19 wherein the separator has a molecular cutoff of about 50,000 daltons, about 100,000 daltons, about 150,000 daltons, about 200,000 daltons or about 250,000 daltons. Page 55 of 56
PCT/US2025/029981 2024-05-17 2025-05-19 Total brine extraction using a vacuum membrane distillation – integrated crystallization reactor (vmd-icr) system Pending WO2025240958A1 (en)

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WO2023102174A1 (en) * 2021-12-02 2023-06-08 Kmx Technologies, Llc Hollow fiber membrane distillation module and process
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US20170036937A1 (en) * 2014-04-21 2017-02-09 Abengoa Water S.L. Method for treating aqueous saline streams
US20220363570A1 (en) * 2015-04-23 2022-11-17 Aquatech International, Llc Method and Apparatus for Advanced Vacuum Membrane Distillation
WO2023102174A1 (en) * 2021-12-02 2023-06-08 Kmx Technologies, Llc Hollow fiber membrane distillation module and process
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