US20130327711A1 - Methods for sustainable membrane distillation concentration of hyper saline streams - Google Patents

Methods for sustainable membrane distillation concentration of hyper saline streams Download PDF

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Publication number
US20130327711A1
US20130327711A1 US13/915,465 US201313915465A US2013327711A1 US 20130327711 A1 US20130327711 A1 US 20130327711A1 US 201313915465 A US201313915465 A US 201313915465A US 2013327711 A1 US2013327711 A1 US 2013327711A1
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membrane
water
stream
passing
distillate
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US13/915,465
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Kerri L. Hickenbottom
Tzahi Cath
Daniel K. Pannell
Jerry Poe
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Great Salt Lakes Minerals Corp
Colorado School of Mines
Compass Minerals Ogden Inc
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Great Salt Lakes Minerals Corp
Great Salt Lake Minerals Corp
Colorado School of Mines
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Priority to US13/915,465 priority Critical patent/US20130327711A1/en
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Assigned to GREAT SALT LAKE MINERALS CORPORATION reassignment GREAT SALT LAKE MINERALS CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: PANNELL, Daniel K., POE, JERRY, MILNE, COREY R.
Publication of US20130327711A1 publication Critical patent/US20130327711A1/en
Assigned to COMPASS MINERALS OGDEN INC. reassignment COMPASS MINERALS OGDEN INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: GREAT SALT LAKE MINERALS CORPORATION
Priority to US15/084,202 priority patent/US11339062B2/en
Assigned to GREAT SALT LAKE MINERALS CORPORATION reassignment GREAT SALT LAKE MINERALS CORPORATION CORRECTIVE ASSIGNMENT TO CORRECT THE PROVISIONAL PATENT APPLICATION NUMBER INSIDE THE ASSIGNMENT DOCUMENT PREVIOUSLY RECORDED AT REEL: 031341 FRAME: 0808. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT. Assignors: PANNELL, Daniel K., POE, JERRY, MILNE, COREY R.
Assigned to COLORADO SCHOOL OF MINES reassignment COLORADO SCHOOL OF MINES CORRECTIVE ASSIGNMENT TO CORRECT THE PROVISIONAL APPLICTION NUMBER AT LINE 7 AND 22 IN ASSIGNMENT DOCUMENT PREVIOUSLY RECORDED AT REEL: 031341 FRAME: 0978. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT . Assignors: CATH, TZAHI, HICKENBOTTOM, Kerri L.
Abandoned legal-status Critical Current

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    • 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
    • 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
    • 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
    • B01D2311/10—Temperature control
    • B01D2311/103—Heating
    • 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
    • B01D2311/10—Temperature control
    • B01D2311/106—Cooling
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/001—Runoff or storm water
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/08—Seawater, e.g. for desalination
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/06—Pressure conditions
    • C02F2301/063—Underpressure, vacuum
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/16—Regeneration of sorbents, filters
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/22—Eliminating or preventing deposits, scale removal, scale prevention
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/30—Wastewater or sewage treatment systems using renewable energies
    • Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy

Definitions

  • the present invention is broadly concerned with liquid-treatment methods, and particularly methods usable for producing concentrated stream or otherwise useful hypersaline brines from a source of non-potable or otherwise impaired water using membrane distillation.
  • saline water such as seawater, lake water, or brackish ground water.
  • Some processes that have been used to desalinate and concentrate water are distillation, crystallization, and membrane processes, such as reverse osmosis, nanofiltration, and electrodialysis.
  • Natural or enhanced evaporation in ponds are also being used for concentration and harvesting of minerals and salts.
  • Water removal rate is a major economic parameter of mineral recovery and production.
  • this parameter is typically limited in existing processes.
  • open ponds are strongly affected by weather and climate.
  • Membrane-based systems may suffer additional problems.
  • membrane fouling and scaling in pressure-driven membrane processes e.g., in reverse osmosis and nanofiltration
  • Pretreatment of the feed water is a way of reducing fouling and scaling, but is typically expensive.
  • Open evaporation ponds are a common practice to concentrate saline and hypersaline water to supply the growing demand for minerals and other beneficial salts or soluble materials.
  • a limited supply of land resources, environmental constraints, and long natural evaporation time limit the rate of mineral separation and harvesting.
  • Membrane distillation is an emerging technology for concentration and extraction of water from a variety of streams. Such examples of process applications include purifying industrial waters (i.e., cooling tower, boilers, etc.), zero-liquid discharge brine management, mineral harvesting, chemical and pharmaceutical purification, food processing, and solvent extraction. In recent years, attention has been drawn to extending the application of membrane distillation as a possible replacement to reverse osmosis (RO) and nanofiltration (NF) for desalination of seawater and brackish water.
  • RO reverse osmosis
  • NF nanofiltration
  • Membrane distillation is a thermally-driven membrane process that can utilize low-grade heat to extract pure water from impaired streams.
  • an impaired stream referred to as the feed stream or source water
  • a distillate stream are flowing on the opposite sides of a hydrophobic, microporous membrane.
  • the difference in partial vapor pressures of the two streams controls the mass transport of water vapors in membrane distillation: water evaporates from a heated feed stream of high salinity, diffuses through the pores of the membrane, and condenses into a cooler distillate stream on the opposite side of the membrane.
  • the present invention provides a method of concentrating water comprising.
  • a membrane distillation unit is provided.
  • the unit comprises a feed side having an inlet and an outlet, and a receiving side having an inlet and an outlet.
  • a membrane is positioned between the feed and receiving sides, and is in communication with both the feed side and the receiving side.
  • the method further comprises passing a source water having a first temperature through either the feed side or the receiving side, and a distillate stream having a second temperature through the other of the feed side or the receiving side.
  • the first temperature is higher than the second temperature, thereby creating a vapor pressure gradient across the membrane, causing a vapor flux from the source water to the distillate stream.
  • FIG. 1 is a schematic hydraulic diagram of a membrane distillation system in flow reversal mode
  • FIG. 2 is a schematic hydraulic diagram of a membrane distillation system in temperature gradient flow reversal mode A;
  • FIG. 3 is a schematic hydraulic diagram of a membrane distillation system in temperature gradient flow reversal mode B;
  • FIG. 4 is a flow schematic of the DCMD bench scale system used in the Example
  • FIG. 5 is a graph showing the water recovered as a function of elapsed time for successive batch experiments performed with the PP22 membrane and filtered GSL feed water at feed and distillate temperatures of 60° C. and 30° C., respectively;
  • FIG. 6 is a graph depicting water recovered as a function of elapsed time for successive batch experiments with alternating feed and distillate channels where feed and distillate channels were alternated three times each, S 1 and S 2 denote the initial feed and distillate sides, respectively, and 1 , 2 , and 3 denote the first, second, and third alternations of the feed and distillate sides; and
  • FIG. 7 is a graph of water flux as a function of elapsed time for successive batch experiments performed with temperature reversal.
  • Spawater (abbreviated “SW”) is saline water from the sea or from any source of brackish water.
  • Source water is water, such as brackish water, impaired water, wastewater, chemical processing streams, sea water, lake water, solar pond water, or reservoir water, input to a treatment process, such as a desalination or concentration process.
  • “Hypersaline water” is supersaturated brine stream produced during the membrane concentration process.
  • “Impaired Water” is any water that does not meet potable water quality standards.
  • “Concentrate” is a by-product of a water treatment processes having a higher concentration of a solute or other material than the feed water, such as a brine by-product produced by a desalination or a concentration process.
  • distillate is a solution having a relatively low osmotic potential that can be used to extract water from a solution having a relatively high osmotic potential.
  • the distillate solution may be a deionized water or a fresh drinking water.
  • “Receiving stream” is a stream that receives water by a water purification or extraction process.
  • the distillate solution is a receiving stream that receives water from a feed stream of water having a high osmotic potential than the receiving stream.
  • “Solar pond” is a natural of an engineered, salinity gradient pond having a higher salt concentration layer at the bottom of the pond and lower salt concentration layer on the top. In a solar pond, heat is captured at the bottom of the pond, and therefore, the temperature of the water at the bottom of the pond is much higher than the temperature of the water at the top of the pond.
  • “Hypersaline evaporation reservoir” is an evaporation pond in which the water is supersaturated and precipitated minerals may have settled at the bottom of the reservoir.
  • upstream and downstream are used herein to denote, as applicable, the position of a particular component, in a hydraulic sense, relative to another component.
  • a component located upstream of a second component is located so as to be contacted by a hydraulic stream (flowing in a conduit for example) before the second component is contacted by the hydraulic stream.
  • a component located down-stream of a second component is located so as to be contacted by a hydraulic stream after the second component is contacted by the hydraulic stream.
  • a membrane is placed in a flow cell, inbetween two flow streams (i.e., a feed/source and a permeate/distillate streams).
  • the feed stream contains a high solute concentration, and the permeate/distillate stream with a solute concentration lower than in the feed stream.
  • the feed stream is salt water and the distillate stream is fresh water.
  • the feed solution (also referred to as “source water”) and the distillate stream can be under positive or negative pressures.
  • the vapor from the solution with the higher partial vapor pressure diffuses across the membrane into the solution of lower partial vapor pressure.
  • the difference in partial vapor pressures of the two solutions is achieved by obtaining a temperature gradient.
  • the temperature of the feed solution is at least 5° C. higher than the temperature of the distillate stream, preferably from about 5° C. to about 70° C. higher, more preferably from about 10° C. to about 50° C. higher, and even more preferably from about 10° C. to about 20° C. higher (15° C. being most ideal).
  • the temperature of the feed stream is about 50° C.
  • the temperature of the distillate stream is about 30° C.
  • the difference in partial vapor pressure (i.e., the feed temperature higher than the distillate temperature) can be changed to reverse the direction of vapor flow through the membrane.
  • the distillate stream can be at least 5° C. higher than the temperature of the feed stream for a period of time. Preferred other temperature differences are similar to those discussed in the preceding paragraph. Accordingly, a portion of the distillate stream vaporizes, diffuses through the pores of the membrane, and condenses in the feed stream. In this particular aspect, the reversal of scaling can be achieved.
  • the changing of the flow regime can be completed periodically. In another example, the changing of the flow regime can be done for any amount of time.
  • the temperature of the feed can be ambient temperature and the temperature of the distillate stream can be greater than ambient temperature. In a particular example, the temperature of the feed stream is 20° C. and the temperature of the distillate stream is 30° C.
  • the feed and distillate solutions can run co-currently in a flow cell containing the membrane. In another embodiment, the feed and distillate solutions can run counter currently in the flow cell. In a particular implementation, the feed and the distillate streams can be switched on either side of the membrane. In a more particular implementation, the feed and the distillate streams sides are switched to opposite sides of the membrane to prevent membrane scaling. In a particular example, the feed side of the membrane becomes the distillate channel and the distillate side of the membrane becomes the feed channel. In a particular example, the changing of the flow regime can be completed periodically. In another example, the changing of the flow regime can be done for any amount of time.
  • the membrane is a hydrophobic, microporous membrane.
  • the membrane is made from Teflon (polytetrafluoroethylene), or polypropylene.
  • the membrane has pore sizes of from about 0.03 microns to about 0.6 microns, preferably from about 0.22 microns to about 0.6 microns, and more preferably from about 0.22 microns to about 0.5 microns.
  • the membrane may have a single layer or multiple layers, and include a support layer. In certain examples, the membrane has one active layer.
  • the membrane is flat.
  • the membrane is placed in a flow cell, in which the membrane is held in place by fasteners or adhesives such as by clamps, screws, pins, tape, glue, or clips.
  • the flat membrane is secured between two plates.
  • a frame (or a gasket) is placed between a plate and the flat membrane.
  • frame may have flow ducts and flow channels and include gaskets and spacers to conduct the distillate solution or the feed solution proximate to the membrane.
  • the flow cell may be a vessel, in which the membrane is spirally wound inside.
  • spacers are used to provide support to the membrane.
  • the spacers are of plastic mesh.
  • the spacers are plastic rods or plastic blocks with channels formed therein.
  • Embodiments of the present disclosure provide methods for concentrating a liquid, such as increasing its solute concentration.
  • the liquid to be concentrated is seawater, saline lake water, brackish-water, impaired-water, wastewater, chemical processing inflow, intermediate, or effluent stream, or other sources (generally referred to as source water).
  • the source water is concentrated to a supersaturation level and potentially precipitating solutes out of solution.
  • systems for concentrating a liquid, such as source water.
  • the system includes a reservoir with hypersaline water, such as supersaturated brine from an evaporation pond, in combination with an upstream membrane distillation unit, or plurality of membrane distillation units, that concentrate the source water feeding the hypersaline evaporation pond.
  • the upstream membrane distillation unit is located hydraulically upstream of the hypersaline water reservoir and downstream from a source water and is configured to also receive a stream of fresh, colder water.
  • the fresh colder water is drawn from the reservoir of fresh water and in another implementation the fresh water is drawn from a cooling tower or heat exchanger.
  • the cold fresh water passes through the upstream forward-osmosis unit on a receiving side of a hydrophobic microporous membrane in the upstream forward-osmosis unit.
  • a stream liquid having a relatively low osmotic potential e.g., a liquid having a low salinity compared to the hypersaline water
  • flows from a reservoir of the source water is heated, and then passes through the upstream membrane distillation unit on a feed side of the membrane, which results in a net transfer of water through the membrane from low salinity source water to the colder fresh water, concentrating the sources water to become hypersaline water.
  • the resulting diluted fresh water is routed to the source water reservoir, and the concentrated sources water is routed into a hypersaline evaporation pond.
  • the diluted fresh water may be used as a source of drinking water.
  • the membrane distillation unit pre-concentrates the source water and thereby reducing the land footprint of the evaporation reservoirs.
  • a further embodiment of the system includes the components of the previous embodiment and further includes a solar pond unit that absorbs and stores thermal energy at the bottom of the pond.
  • the solar pond unit is located upstream of the upstream membrane distillation unit.
  • the solar pond unit provides heat to elevate the temperature, and thus the vapor pressure, of the source water feeding the upstream membrane distillation unit.
  • Hot water from the solar pond unit, or plurality of solar pond units is passing through a heat exchange unit upstream from the membrane distillation unit, thereby heating the incoming source water and cooling the hot solar pond water.
  • the hot water from the solar pond unit is blended with the source water stream in the heat exchanger unit upstream from the upstream membrane distillation unit.
  • an evaporative membrane concentration unit may be advantageous compared to other concentration techniques, such as reverse osmosis, because the evaporative membrane concentration unit, such as a membrane distillation unit, may be less susceptible to membrane fouling. Furthermore, the reduced susceptibility to membrane fouling may reduce the need to pre-treat the feed stream for the evaporative membrane concentration unit.
  • the systems described above may be used for processes other than the concentration of minerals in hypersaline reservoirs.
  • Other processes may include concentration of brackish water, concentration of foods or beverages, and concentration or purification of chemical or pharmaceutical products.
  • the rate of concentration through currently commercially available membrane is relatively low under the conditions encountered in a mineral recovery plant. Nevertheless, this low concentration rate is more than two orders of magnitude higher than the natural evaporation in many natural evaporation ponds.
  • Membrane distillation is a membrane separation process that combines simultaneous mass and heat transfer through a hydrophobic, microporous membrane. Mass transfer in this process is carried out by evaporation of a volatile solute or a volatile solvent (e.g., water), when the solute is non-volatile.
  • the driving force for mass transfer in the process is the vapor pressure difference across the membrane.
  • Direct contact membrane distillation is one of four basic configurations of MD.
  • a feed solution at elevated temperature is in contact with one side of the membrane, and colder water is in direct contact with the opposite side of the membrane; it is mainly the temperature difference between the liquids, and to some extent their solute concentration, that induces the vapor pressure gradient for mass transfer.
  • Mass transfer in DCMD is a three-step process involving: (1) diffusive transport from the feed stream to the membrane interface; (2) combined diffusive and convective transport of the vapors through the membrane pores; and (3) condensation of the vapors on the membrane interface on the product side of the membrane.
  • the configuration of the membrane unit is slightly modified so that the distillate (fresh cold water) stream flows under a negative pressure (vacuum) on the product side of the membrane. Further deepening of the vacuum on the distillate side can result in a linear increase in the flux of water.
  • water flux for the deepest vacuum investigated (55 kPa) increased up to 84%.
  • a relatively high water flux can be realized and the feed stream can be substantially concentrated.
  • a distillate stream having a low solute concentration and a temperature 20° C. lower than that of seawater can produce flux of at least 15 Liter/(m 2 ⁇ hr) of clean water through the suitable membrane distillation membrane into the distillate stream from a stream having a solute concentration of seawater or even five times that of seawater.
  • saline water can be further concentrated even to above its solutes saturation concentrations using vapor pressure difference (or temperature difference) across the membrane distillation membrane and correspondingly reducing the energy required to concentrate the saline feed stream.
  • the concentrated hypersaline brine produced may be used as a feed stream to mineral recovery systems.
  • Low performance may include low water flux due to a cake layer of organic or inorganic solids that have accumulated on the membrane surface on the feed side; pore blockage due to penetration of solids into the membrane pores; and/or pore wetting, which occurs due to penetration of feed/source water into the membrane pore and results in convective flow of feed water into the distillate water on the receiving side of the membrane. The latter will result in low rejection of salts and other solutes by the membrane distillation membrane.
  • MDFR membrane distillation flow reversal
  • MDTGR membrane distillation temperature gradient reversal
  • the disclosed methods can be used for a variety of membrane distillation operations, including, but not limited to, direct contact membrane distillation, vacuum enhanced membrane distillation, air gap membrane distillation, etc. Additionally, the disclosed methods can present a number of advantages compared to the aforementioned process applications (i.e., process applications include purifying industrial waters, zero-liquid discharge brine management, mineral harvesting, chemical and pharmaceutical purification, food processing, and solvent extraction), particularly in desalination and brine management.
  • An advantage of operating membrane systems in MDFR and MDTGR mode is that they can improve membrane integrity by mitigating scale formation and membrane wetting. In mitigating membrane scaling and wetting, the membrane lifetime can be extended, thus reducing the need for membrane replacement and lowering maintenance costs. Additionally, implementing these unique flow reversal methods can clean the membrane in situ, without disturbing normal operations, and eliminate the need for cleaning with chemicals. Finally, operating in flow reversal mode improves operation once the membrane has scaled.
  • Cost benefits are also associated with this process and include using low-grade heat source. Additionally, the temperature gradient used for MDTGR may be achieved by capitalizing on the natural temperature gradient present in the cooler, incoming feed stream and the already-heated distillate stream.
  • MDFR Membrane Distillation Flow Reversal
  • a first exemplary embodiment of the sustainable water-treatment process includes one or more membrane distillation treatment stages to increase source water salinity and simultaneously produce water, while maintaining high permeability and low scaling/fouling of the membrane distillation membrane.
  • a concentration step is performed in which the source water is concentrated by evaporating water from the source water through a membrane distillation membrane into a fresh water (distillate) stream that in the process is becoming further diluted and warmer, due to absorption of pure hot vapors that crossed the membrane.
  • the fresh water receiving stream is supplied by a distillate reservoir of fresh water, for example river water, or lake water, or groundwater.
  • the feed stream is pumped from a source water evaporation reservoir ( 103 ) using a pump ( 111 ).
  • the feed stream flows through line ( 121 ), a heating device ( 109 ) (e.g., external heater or heat exchanger), a 4-way crossover valve ( 107 ), and the primary feed side of the membrane distillation flow cell/device ( 105 ), which houses a membrane distillation membrane ( 106 ).
  • the concentrated source water feed stream exits the flow cell through a 4-way crossover valve ( 108 ) and returns to the evaporation reservoir ( 103 ) via line ( 123 ).
  • the distillate stream is pumped ( 112 ) through line ( 120 ).
  • the distillate stream flows through a cooling device ( 110 ) (e.g., external cooler or heat exchanger), bypasses a 4-way crossover valve ( 107 ), proceeds through the primary distillate receiving side of the membrane distillation membrane in the flow cell ( 105 ), flows through a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • a cooling device 110
  • bypasses a 4-way crossover valve ( 107 ) proceeds through the primary distillate receiving side of the membrane distillation membrane in the flow cell ( 105 ), flows through a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • Crossover valve ( 107 ) is activated such that the distillate stream ( 120 ) is routed to the primary feed inlet of the membrane flow cell, and the distillate stream is pumped to flush the primary feed side of the membrane cell. Rinsing waste is sent back to either the evaporation reservoir ( 103 ) or source water reservoir ( 101 ). At this time, the concentrated feed from the evaporation reservoir can be drained via stream ( 125 ) and sent for further processing. The evaporator reservoir can then be replenished with feed from the source reservoir ( 101 ) via line ( 102 ). The distillate from the distillate reservoir ( 104 ) could also be extracted for beneficial use via line ( 124 ).
  • Crossover valves ( 107 ) and ( 108 ) are activated to an intermittent mode in which the 4-way crossover valves re-route the feed and distillate streams to the opposite sides of the membrane.
  • the feed stream continues to flow clockwise through lines ( 121 ) and ( 123 ); however, the stream is now bypassed to the primary distillate side of the membrane.
  • the distillate stream continues to flow counterclockwise through lines ( 120 ) and ( 122 ); however, the stream is now passed to the primary feed side of the membrane.
  • Crossover valve ( 107 ) is deactivated to its original configuration (i.e., the distillate stream enters the primary distillate side of the membrane) while crossover valve ( 108 ) remains open. Consequently, enough distillate stream is pumped to flush the primary distillate side of the membrane. Rinsing waste is sent back to either the evaporation reservoir ( 103 ) or source water reservoir ( 101 ). Return to operation mode 1.
  • Feed stream is pumped ( 111 ) through line ( 121 ).
  • Feed stream flows through a heating device ( 109 ) (e.g., external heater or heat exchanger), bypasses a 3-way valve ( 201 ) and a 4-way crossover valve ( 107 ), proceeds through the primary feed side of the membrane distillation membrane flow cell ( 105 ), passes a 4-way crossover valve ( 108 ) and a 3-way valve ( 203 ), and returns to the evaporation reservoir ( 103 ) via line ( 123 ).
  • a heating device 109
  • a 3-way valve 201
  • 4-way crossover valve 107
  • passes a 4-way crossover valve ( 108 ) and a 3-way valve ( 203 ) and returns to the evaporation reservoir ( 103 ) via line ( 123 ).
  • Distillate stream flows through a cooling device ( 110 ) (e.g., external cooler or heat exchanger), bypasses a 4-way crossover valve ( 107 ), proceeds through the primary distillate side of the membrane flow cell ( 105 ), bypasses a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • a cooling device e.g., external cooler or heat exchanger
  • bypasses a 4-way crossover valve ( 107 ) proceeds through the primary distillate side of the membrane flow cell ( 105 ), bypasses a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • the source water passes the 4-way crossover valve ( 108 ), through the 3-way valve ( 203 ), and returns to the source water reservoir ( 101 ) via line ( 204 ).
  • the distillate stream at a higher temperature than the source water stream, resumes being pumped on the primary distillate side of the membrane.
  • the distillate stream flows through a cooling device ( 110 ) (i.e., external cooler or heat exchanger), passes a 4-way crossover valve ( 107 ), proceeds through the primary distillate receiving side of the membrane flow cell ( 105 ), passes through a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • a cooling device 110
  • passes a 4-way crossover valve ( 107 ) proceeds through the primary distillate receiving side of the membrane flow cell ( 105 ), passes through a 4-way crossover valve ( 108 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • the system is returned to operation mode 1.
  • the feed stream is pumped from the evaporation reservoir ( 103 ) using a pump ( 111 ).
  • the feed stream flows through line ( 121 ), through a heating device ( 109 ) (e.g., external heater or heat exchanger), passes a 4-way crossover valve ( 107 ), and through the primary feed side of the membrane distillation flow cell/device ( 105 ), which houses an MD membrane ( 106 ).
  • the feed exits the flow cell through a 4-way crossover valve ( 108 ) and returns to the evaporation reservoir ( 103 ) via line ( 123 ).
  • the distillate stream is pumped ( 112 ) through line ( 120 ).
  • the distillate stream flows through a cooling device ( 110 ) (e.g., external cooler or heat exchanger), passes through a away valve ( 301 ) and a 4-way crossover valve ( 107 ), proceeds through the primary distillate receiving side of the membrane distillation flow cell ( 105 ), passes through a 4-way crossover valve ( 108 ) and a 3-way valve ( 302 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • a cooling device 110
  • proceeds through the primary distillate receiving side of the membrane distillation flow cell ( 105 ) passes through a 4-way crossover valve ( 108 ) and a 3-way valve ( 302 ), and returns to the distillate reservoir ( 104 ) via line ( 122 ).
  • the 3-way valves ( 301 and 302 ) are activated, and heated water (at a temperature greater than the feed water) from an external reservoir ( 305 ) is circulated on the primary distillate side of the membrane via lines ( 303 ) and ( 304 ). Operations proceed as in Operation mode 1. After a brief period of time, the system is returned to operation mode 1.
  • a hydrophobic microporous membrane (PP22) was acquired from GE/Osmonics (Minnetonka, Mn).
  • the PP22 is an isotropic membrane made of polypropylene (PP), and is approximately 150 microns thick.
  • the membrane has a nominal pore size of 0.22 microns and a porosity of approximately 70%. After experiments, the membranes were rinsed with deionized water and stored in a desiccator until analysis.
  • FIG. 4 A flow schematic of the test unit is illustrated in FIG. 4 .
  • the thermally insulated feed and distillate reservoirs were connected to gear pumps (Micropump, Cole Parmer, Vernon Hills, Ill.) that circulated the feed and distillate streams co-currently on the opposite sides of the membrane.
  • Thermocouples were installed at the inlets of the feed and distillate channels and connected to the SCADA system.
  • the flow rate of the two streams was 1.6 L min ⁇ 1 .
  • the overflow rate was used to calculate water flux through the membrane.
  • the conductivity of the distillate reservoir was continuously measured (Waterproof pH/CON 300 Meter, Oakton Instruments, Vernon Hills, Ill.) and changes were used to calculate salt rejection and detect membrane wetting. The results from the following procedures are reported in FIGS. 5-7 .
  • the GSL water was characterized using standard analytical methods. Water samples were prepared and analyzed for dissolved solids according to Standard Methods (APHA, 2005). Samples were diluted and filtered through a 0.45-micron filter and analyzed for anions and cations with an ion chromatograph (Model ICS-90, Dionex, Sunnyvale, Calif.) and an inductively coupled plasma atomic emission spectrometer (ICP-AES) (Optima 5300 DV, PerkinElmer Inc., Waltham, Mass.), respectively. The average total dissolved solids (TDS) concentration of the GSL water from the Bear River Bay was approximately 150,000 mg/L, most of which is sodium chloride ( ⁇ 84%/wt.). A detailed ionic composition of the GSL water is summarized in Table 1.

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US20160158666A1 (en) * 2013-07-29 2016-06-09 Industrial Advanced Services Fz-Llc Methods and facilities for thermal distillation with mechanical vapour compression
US20160304375A1 (en) * 2015-04-14 2016-10-20 Hitachi, Ltd. Produced water treatment system
US20170057854A1 (en) * 2015-09-01 2017-03-02 Pepsico, Inc. Ion Exchange Regeneration Process Utilizing Membrane Distillation
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US11014016B2 (en) 2019-10-24 2021-05-25 Jay Dotter Electric water desalination assembly
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US20160158666A1 (en) * 2013-07-29 2016-06-09 Industrial Advanced Services Fz-Llc Methods and facilities for thermal distillation with mechanical vapour compression
US10702791B2 (en) * 2013-07-29 2020-07-07 Industrial Advanced Services Fz-Llc Methods and facilities for thermal distillation with mechanical vapour compression
US20160038879A1 (en) * 2013-11-27 2016-02-11 Sumitomo Electric Industries, Ltd. Membrane distillation module and wastewater treatment apparatus
US20160039686A1 (en) * 2013-11-27 2016-02-11 Sumitomo Electric Industries, Ltd. Wastewater treatment method, membrane distillation module and wastewater treatment apparatus
US20160031727A1 (en) * 2013-11-27 2016-02-04 Sumitomo Electric Industries, Ltd. Wastewater treatment method, membrane distillation module and wastewater treatment apparatus
CN103762004A (zh) * 2014-01-22 2014-04-30 清华大学 一种浓缩放射性废水的方法和系统
US20160304375A1 (en) * 2015-04-14 2016-10-20 Hitachi, Ltd. Produced water treatment system
JP2016198745A (ja) * 2015-04-14 2016-12-01 株式会社日立製作所 随伴水処理システム
US20170057854A1 (en) * 2015-09-01 2017-03-02 Pepsico, Inc. Ion Exchange Regeneration Process Utilizing Membrane Distillation
US10357745B2 (en) * 2016-06-14 2019-07-23 Korea Institute Of Science And Technology Membrane distillation system which is capable of real-time monitoring on membrane wetting
US10604426B2 (en) 2016-12-23 2020-03-31 Magna Imperio Systems Corp. High efficiency electrochemical desalination system that incorporates participating electrodes
WO2018118201A1 (en) * 2016-12-23 2018-06-28 Connor Michael James High efficiency electrochemical desalination system that incorporates participating electrodes
US20220017385A1 (en) * 2019-05-16 2022-01-20 The Trustees Of Columbia University In The City Of New York Temperature swing solvent extraction for descaling of feedstreams
US11014016B2 (en) 2019-10-24 2021-05-25 Jay Dotter Electric water desalination assembly
US20220204374A1 (en) * 2020-12-29 2022-06-30 Kuwait University Zero pollution hybrid desalination and energy production system
US11396469B2 (en) * 2020-12-29 2022-07-26 Kuwait University Zero pollution hybrid desalination and energy production system

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