Air cooling system

Abstract

An air cooling system includes an evaporator adapted to cool air and a liquid reservoir adapted to store and supply liquid to the evaporator. The air cooling system also includes a pressure reducer system fluidly connected to the evaporator and adapted to generate a relatively low pressure within the evaporator to facilitate conversion of liquid flowing through the evaporator into vapor. The pressure reducer system includes a liquid ejector having an inlet portion adapted to receive liquid from the liquid reservoir, a throat portion disposed downstream of the inlet portion and fluidly connected to the evaporator, and an outlet portion disposed downstream of the throat portion and configured to increase the pressure within the liquid ejector. The pressure reducer system also includes a pump fluidly connected to the liquid ejector and the liquid reservoir to supply liquid from the liquid reservoir to the liquid ejector.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Provisional Patent Application Nos. 62 / 704,864, filed May 31, 2020, and 63 / 129,206, filed December 22, 2020, the contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] The present disclosure relates to an air cooling system having an evaporator and a liquid ejector to reduce the pressure inside the evaporator to cool air flowing over the evaporator. Background Art

[0004] With climate change, global warming, and urbanization, the demand for air cooling systems to cool occupied spaces is increasing. Air cooling systems typically include refrigerant or desiccant dehumidifiers to remove heat and humidity from the air. However, air conditioners require high energy to operate. Traditional refrigerant-based air conditioners manage sensible and latent heat loads in a combined process, extracting moisture through vapor condensation around the heat exchanger during the refrigerant evaporation phase. This approach is energy-intensive and inefficient.

[0005] Air coolers, such as desert coolers or cooling towers, are also used to provide relatively cool air to occupied spaces. These systems typically operate based on the principle of water evaporation, cooling the air by evaporating water from surfaces. However, these systems may not work well in humid environments.

[0006] U.S. Patent 8,496,732 discloses an air cooling system for dehumidifying air by establishing a humidity gradient across a water-selective permeable membrane in a dehumidifying device. The humidity gradient is established by using a vacuum pump to create a vacuum on one side of the membrane (the vacuum pump creates the vacuum by compressing air). Due to the compressible nature of air, creating a vacuum by compressing air is relatively inefficient and consumes more energy. In addition, vacuum pumps that create a vacuum by compressing air typically use a large amount of non-condensable fluid (e.g., dry air) for operation and do not react well in environments containing high condensable loads such as water vapor or moisture. In addition, the air cooling system includes a condenser for condensing the water vapor extracted from the air.

[0007] Therefore, there remains a need for improved air cooling systems to facilitate removing heat from air that is energy efficient. SUMMARY OF THE INVENTION

[0009] In a first aspect, an air cooling system is disclosed. The air cooling system is pressurizable and vacuum-resistant. The system includes an evaporator adapted to cool air passing therethrough, and a liquid reservoir fluidly connected to the evaporator for storing and supplying liquid to the evaporator. The system also includes a pressure reducer system fluidly connected to the evaporator and adapted to generate a pressure within the evaporator that is less than or equal to the saturated vapor pressure of the liquid at ambient temperature, thereby promoting conversion of at least a portion of the liquid flowing through the evaporator into vapor. The pressure reducer system includes a liquid ejector and a pump. The liquid ejector includes an inlet portion adapted to receive liquid from the liquid reservoir, and a throat portion disposed downstream of the inlet portion and fluidly connected to the evaporator. The throat portion is adapted to increase the velocity of the liquid received from the inlet portion. The liquid ejector also includes an outlet portion disposed downstream of the throat portion and configured to increase the pressure within the liquid ejector to promote condensation of vapor received from the evaporator. The pump is fluidly connected to the liquid ejector and the liquid reservoir and configured to supply liquid from the liquid reservoir to the liquid ejector.

[0010] According to one embodiment, the pressure reducer system further comprises a booster pump disposed upstream of the liquid ejector and fluidically connected to the evaporator to reduce the pressure inside the evaporator to a pressure less than the saturated vapor pressure of the liquid.

[0011] In one embodiment, the liquid is water and the booster pump facilitates reducing the pressure to a value less than or equal to 31.7 mbarA at 25°C.

[0012] In one embodiment, the booster pump facilitates reducing the pressure to a value less than the saturated vapor pressure of the liquid in the evaporator.

[0013] In one embodiment, the booster pump facilitates reducing the pressure to a value of 20-40 mbarA or 10-20 mbarA.

[0014] According to one embodiment, the reservoir comprises a drain valve for facilitating drainage of the liquid from the reservoir when the level of the liquid reaches above a first critical level.

[0015] In some embodiments, the reservoir is made of a thermally conductive material to facilitate heat transfer from the liquid stored inside the reservoir to the environment.

[0016] In some embodiments, the air cooling system further comprises a heat exchanger fluidly connected to the liquid ejector and configured to receive at least a portion of the liquid exiting the liquid ejector. The heat exchanger is configured to cool the received liquid.

[0017] In one embodiment, a heat exchanger is provided upstream of the liquid reservoir and supplies cooled liquid to the liquid reservoir.

[0018] In one embodiment, the liquid ejector is a water ejector adapted to receive liquid water from a pump.

[0019] According to one embodiment, the air cooling system further comprises a metering valve disposed between the liquid reservoir and the evaporator to control the flow of liquid from the liquid reservoir to the evaporator.

[0020] In some embodiments, the air cooling system further comprises a dehumidification core disposed upstream or downstream of the evaporator and adapted to be fluidically coupled to the liquid ejector. The dehumidification core comprises an air channel, at least one vapor channel separated from the air channel, and a membrane separating the at least one vapor channel from the air channel and adapted to facilitate the removal of moisture from air flowing through the air channel. The membrane is selectively permeable to water and water vapor and impermeable to air. Furthermore, the throat portion is fluidically coupled to the at least one vapor channel to generate a relatively lower pressure within the at least one vapor channel than within the air channel, thereby facilitating the flow of moisture from the air flowing through the air channel to the at least one vapor channel. Furthermore, the outlet portion facilitates condensation of water vapor received from the at least one vapor channel.

[0021] In one embodiment, the membrane comprises, consists essentially of, or consists of a sulfonated polymer.

[0022] According to one embodiment, the air cooling system further includes a valve disposed between the pressure reducer system and the dehumidification core to control fluid connection between the dehumidification core and the pressure reducer system.

[0023] In one embodiment, upon activation of the air cooling system the pressure within the liquid reservoir is reduced to a value that is at least 5%, or 7-20%, or at most 25% greater than the saturated vapour pressure of the liquid at ambient temperature.

[0024] In one embodiment, when the liquid is water, the pressure in the reservoir is reduced to a value of 40-150 mbarA upon starting the air cooling system.

[0025] In one embodiment, the air cooling system is pre-conditioned prior to start-up to a pressure value >5%, or 7-20%, or at most 25% greater than the saturated vapor pressure of the liquid.

[0026] In a second aspect, an air cooling system is disclosed. The air cooling system includes at least one dehumidification core defining an air channel and at least one vapor channel separated from the air channel. The dehumidification core includes a membrane separating the at least one vapor channel from the air channel. The membrane is adapted to facilitate the removal of moisture from air flowing through the air channel. In addition, the membrane is selectively permeable to water and water vapor and impermeable to air. The air cooling system also includes an evaporator adapted to cool air passing over it and disposed upstream or downstream of the dehumidification core. In addition, the air cooling system includes a pressure-resistant liquid reservoir for storing liquid and fluidically connected to the evaporator for supplying liquid to the evaporator. In addition, the air cooling system includes a pressure reducer system fluidly connected to at least one of the evaporator or the dehumidification core. The pressure reducer system is adapted to generate a pressure within the evaporator that is less than or equal to the saturated vapor pressure of the liquid at ambient temperature to facilitate conversion of at least a portion of the liquid flowing through the evaporator into vapor when fluidically connected to the evaporator. The pressure reducer system is also adapted to generate a relatively lower pressure in at least one vapor channel than in the air channel to promote the extraction of moisture from the air flowing through the air channel to the at least one vapor channel when connected to the dehumidification core fluid. The pressure reducer system includes a liquid ejector and a pump. The liquid ejector has an inlet portion adapted to receive liquid from a liquid reservoir, and a throat portion disposed downstream of the inlet portion and connected to at least one evaporator or at least one vapor channel fluid. The throat portion is adapted to increase the velocity of the fluid received from the inlet portion. The liquid ejector also includes an outlet portion disposed downstream of the throat portion and configured to increase the pressure inside the liquid ejector to promote condensation of vapor received from at least one evaporator or dehumidification core. The pump is fluidly connected to the liquid ejector and the liquid reservoir and is configured to supply liquid from the liquid reservoir to the liquid ejector.

[0027] According to one embodiment, the air cooling system further comprises at least one valve to control fluid connection of the pressure reducer system to at least one of the evaporator or the dehumidification core.

[0028] In one embodiment, the at least one valve includes a first valve to control the fluid connection between the evaporator and the pressure reducer system, and a second valve to control the fluid connection between the dehumidification core and the pressure reducer system.

[0029] In one embodiment, the pressure reducer system further comprises a booster pump arranged upstream of the liquid ejector to reduce the pressure inside at least one evaporator to a pressure less than the saturated vapor pressure of the liquid or to reduce the pressure inside at least one vapor channel of the dehumidification core to a pressure less than the saturated vapor pressure of water.

[0030] In one embodiment, the liquid is water and the booster pump facilitates reducing the pressure to a value less than or equal to 31.7 mbarA at 25°C.

[0031] In one embodiment, the booster pump facilitates reducing the pressure to a pressure of the saturated vapor pressure of the liquid in the evaporator, or a value of 20-40 mbarA or 10-20 mbarA.

[0032] In one embodiment, the reservoir includes a drain valve for facilitating drainage of liquid from the reservoir when the level of the liquid reaches above a first critical level.

[0033] In some embodiments, the reservoir is made of a thermally conductive material to facilitate heat transfer from the liquid stored inside the reservoir to the environment.

[0034] In one embodiment, the air cooling system further comprises a heat exchanger fluidly connected to the liquid ejector and configured to receive at least a portion of the liquid exiting the liquid ejector. The heat exchanger is configured to cool the received liquid. In some embodiments, the heat exchanger is positioned upstream of the liquid reservoir and supplies cooled liquid to the liquid reservoir.

[0035] In one embodiment, the liquid ejector is a water ejector adapted to receive liquid water from a pump.

[0036] In one embodiment, the air cooling system further comprises a metering valve disposed between the liquid reservoir and the evaporator to control the flow of liquid from the liquid reservoir to the evaporator.

[0037] In one embodiment, upon activation of the air cooling system, the pressure inside the liquid reservoir is reduced to a value >5%, or 7-20%, or at most 25% greater than the saturated vapor pressure of the liquid at ambient temperature.

[0038] In one embodiment, when the liquid is water and the air cooling system is started up, the pressure inside the reservoir is reduced to a value of at least 30 mbarA, or 40-150 mbarA, or less than 120 mbarA.

[0039] In one embodiment, prior to start-up, the air cooling system is pre-conditioned to a pressure value >5%, or 7-20%, or at most 25% greater than the saturated vapor pressure of the liquid.

[0040] BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram of an embodiment of an air cooling system having an evaporator and a pressure reducer system coupled to the evaporator.

[0042] Figure 2is a schematic diagram of an embodiment of an air cooling system having an evaporator and a pressure reducer system coupled to the evaporator and depicting a heat exchanger positioned upstream of a liquid ejector.

[0043] Figure 3 is a schematic diagram of an embodiment of an air cooling system having an evaporator and a pressure reducer system coupled to the evaporator and depicting a heat exchanger independently coupled to a liquid receiver of the pressure reducer system.

[0044] Figure 4 Schematic diagram illustrating an embodiment of an air cooling system having an evaporator, a dehumidification core having an air passage separated from a vapor passage by a membrane, and a pressure reducer system coupled to the evaporator and the dehumidification core.

[0045] Figure 5 is a schematic top view of a portion of an embodiment of a dehumidification core having a flow of water vapor from air flowing through air channels to vapor channels.

[0046] Figure 6 is a perspective view of an embodiment of a dehumidification core having air channels extending from a first side to a second side.

[0047] Figure 7 yes Figure 4 A cross-sectional view of a dehumidification core depicts the vapor channels extending substantially perpendicular to the direction in which the air channels extend. Detailed Description of the Invention

[0049] The following terms used in this specification have the following meanings:

[0050] "Ion exchange capacity" or IEC refers to the total number of active sites or functional groups in a polymer responsible for ion exchange. IEC is typically determined using conventional acid-base titration methods, see, for example, International Journal of Hydrogen Energy, Vol. 39, No. 10, March 26, 2014, pp. 5054-5062, "Determination of the ion exchange capacity of anion-selective membrane." IEC is the reciprocal of "equivalent weight," or EW, where an equivalent weight is the weight of polymer required to provide one mole of exchangeable protons.

[0051] "At least one of A or B" as an example of "at least one of [the group such as A, B, or C]" or "any of [the group such as A, B, or C]" means a single member from the group, more than one member from the group, or a combination of members from the group. For example, at least one of A, B, or C includes, for example, only A, only B, or only C, as well as all other combinations of A and B, A and C, B and C, or A, B and C, or A, B and C.

[0052] A list of embodiments presented as "A, B, or C" should be interpreted to include embodiments with only A, only B, only C, "A or B," "A or C," "B or C," or "A, B, or C." For example, "at least one of an evaporator or a dehumidification core" includes only an evaporator, only a dehumidification core, and both an evaporator and a dehumidification core.

[0053] The present disclosure relates to an air cooling system for facilitating cooling air and / or removing moisture from the air. The system comprises an evaporator, a liquid reservoir, and a pressure reducer system having a liquid ejector and a pump in communication with the liquid ejector and the liquid reservoir, and is essentially composed of or consists of an evaporator, a liquid reservoir, and a pressure reducer system having a liquid ejector and a pump in communication with the liquid ejector and the liquid reservoir. In some embodiments, the air cooling system further comprises a dehumidification core disposed upstream or downstream of the evaporator and adapted to be fluidically connected to the liquid ejector. The dehumidification core is characterized in that it has a membrane that is selectively permeable to water and water vapor and impermeable to air.

[0054] Liquids for use in air cooling systems Although the liquid ejectors mentioned herein are considered to be water ejectors, and water is used as the liquid or motive fluid, it is understood that any other suitable incompressible liquid may also be used in the air cooling system. Thus, reference to water may include other liquids such as, but not limited to, acetone, acetonitrile, acrolein, acrylonitrile, alcohols (e.g., ethanol, allyl alcohol, butanol, methanol, propyl alcohol), allylamine, aniline, anisole, benzene, chloroform, cyclohexane, cyclopentane, diethyl ether, ethanol, chemical refrigerants (including R-11, R-12, R-22), isopentane, and methyl acetate.

[0055] Liquid Injectors:The liquid ejector operates on a Venturi effect and includes a compression throat portion having a relatively small diameter through which a liquid, such as water, is pumped. As the liquid flows through the throat portion, the rate or velocity of the liquid increases, resulting in a lower pressure inside the throat portion. This low pressure is connected to the vapor channel and / or the evaporator. In this way, when connected to the dehumidification core, the liquid ejector promotes the creation of a pressure differential between the air channel and the vapor channel of the dehumidification core to achieve the flow of moisture from the air flowing through the air channel to the vapor channel. In addition, the liquid ejector promotes the creation of a vacuum or low pressure inside the evaporator to achieve the conversion of at least a portion of the liquid flowing inside the evaporator into vapor. In order to control the reduction in pressure inside the throat portion, the rate and volume of liquid entering the inlet portion of the liquid ejector are controlled.

[0056] In one embodiment using water, the liquid ejector can generate a vacuum pressure of 40-120 mbarA. It will be appreciated that the vacuum generation capability of the liquid ejector is limited by the saturated vapor pressure of the liquid. In one embodiment, the liquid ejector can generate a pressure of ≤960 mbar gauge.

[0057] In order to further increase the vacuum level inside the vapor channel or reduce / decrease the pressure inside the vapor channel, a booster pump is arranged upstream of the liquid ejector and fluidically connected to at least one of the evaporator and the dehumidification core.

[0058] Booster pump: A booster pump is a root pump that typically includes at least one pair of meshing blades rotating in opposite directions. Fluid is trapped in a pocket around the blades and carried from the inlet side to the outlet side. The booster pump helps reduce the pressure inside the vapor channel to a pressure less than or equal to the vapor partial pressure of water and / or helps reduce the pressure inside the evaporator to a pressure less than or equal to the saturated vapor pressure of the liquid at ambient temperature. In one embodiment, the liquid is water, and the saturated vapor pressure of water is approximately 31.7 mbarA at 25°C. In one embodiment, the booster pump combined with the liquid ejector helps generate a pressure less than or equal to 20 mbarA inside the vapor channel and / or evaporator. In some embodiments, the booster pump helps reduce the pressure to a value of 10-20 mbarA. In one embodiment, the booster pump reduces the pressure to a value less than or equal to 10 mbarA. In some embodiments, the booster pump helps reduce the pressure to a value of 20-40 mbarA. In some embodiments, the booster pump helps reduce the pressure to a value less than 150 mbarA.

[0059] membrane:The membranes used in the system are moisture permeable membranes having excellent water vapor transmission rate (MVTR) characteristics and excellent ion exchange capacity (IEC). The membranes are characterized by selective permeability, i.e., permeability to air moisture but impermeability to other air components. In some embodiments, the membranes are largely impermeable to air. In some embodiments, the membranes are characterized by an MVTR of >100, or >500, or 1,000 g / m 2 / day. ASTM E-96B and ASTM F1249 specify standard methods for determining MVTR. In some embodiments, the membrane is characterized by an air permeability of less than 5 g / m 2 / sky.

[0060] In some embodiments, the membranes are characterized by favorable ion exchange capacity and proton conductivity, as well as a glass transition temperature, thereby providing flexibility and material strength, and good stability and swelling properties even when hydrated. The membranes are formed primarily or substantially entirely from a sulfonated polymer (SP) that is sufficiently sulfonated to contain 10-100 mol% sulfonic acid or sulfonate functional groups, based on the number of monomer units in the copolymer. In some embodiments, the SP is used to form a coating on a substrate surface, where the substrate is made of the same or a different material. In other embodiments, the membrane is in the form of a single or multiple SP layers or films, where each SP layer or film has a certain or preselected thickness.

[0061] In some embodiments, the SP is a sulfonated block copolymer having a block copolymer molecular structure comprising three or more blocks, designed to phase separate and form ion-conducting domains that enable water transport (a process that can be accelerated by applying a voltage). In some embodiments, the SP is selected from perfluorosulfonic acid polymers such as sulfonated tetrafluoroethylene copolymers, polystyrene sulfonates, sulfonated block copolymers, polysulfones such as polyethersulfone, polyketones such as polyetherketone, and mixtures thereof.

[0062] In some embodiments, the sulfonated polymer is characterized as being fully or selectively sulfonated to contain 10-100 mol% sulfonic acid or sulfonate functional groups ("degree of sulfonation"), based on the number of sulfonatable monomeric units in the sulfonated copolymer. In some embodiments, the sulfonated polymer has a degree of sulfonation of >25 mol%, or >50 mol%, or <95 mol%, or 25-70 mol%.

[0063] In some embodiments, the sulfonated polymer is characterized as being bactericidal, killing at least 99% of microorganisms within 5 minutes of contact with the coating material.

[0064] In some embodiments, the sulfonated polymer is a sulfonated block copolymer having one or more copolymer block structures corresponding to any of the following: ABA, ABABA, (ABA) n X, (AB) n X, ADBDA, ABDBA, (ADB) n X, (ABD) n X or a mixture thereof, wherein n is an integer from 2 to about 30, X is a coupling agent residue, and wherein each D block is preferably a sulfonation-resistant polymer block. In some embodiments, SP has a linear structure corresponding to: ABA, (AB)2X, ABDBA, (ABD)2X, ADBDA, and (ADB)2X, or corresponding to (AB) n X and (ADB) n A radial structure of X, wherein n is 3 to 6. Two or more of the A, B, C, and D blocks may be the same or different.

[0065] In some embodiments, the A block is a polymer segment of an acrylate or methacrylate. In some embodiments, the A block is selected from polymerized para-substituted styrene monomers, ethylene, alpha olefins of 3-18 carbon atoms, 1,3-cyclodiene monomers, monomers of conjugated dienes having a vinyl content of less than 35 mol% before hydrogenation, acrylates, methacrylates, and mixtures thereof. If the A block is a polymer of a 1,3-cyclodiene or conjugated diene, the block is preferably hydrogenated after polymerization of the block copolymer and before sulfonation of the block copolymer. If the A block is a hydrogenated polymer of a 1,3-cyclodiene monomer, such monomer may be selected from 1,3-cyclohexadiene, 1,3-cycloheptadiene, and 1,3-cyclooctadiene. The A block may contain up to 15 mol% of a vinyl aromatic monomer, such as those present in the B block.

[0066] The B block may contain about 10-100 mole percent sulfonic acid or sulfonate functionality, based on the number of monomer units, and comprises one or more segments of polymerized vinyl aromatic monomers selected from the group consisting of unsubstituted styrene monomers, ortho-substituted styrene monomers, meta-substituted styrene monomers, alpha-methylstyrene monomers, 1,1-diphenylethylene monomers, 1,2-diphenylethylene monomers, and mixtures thereof.

[0067] The D block may comprise a hydrogenated polymer or copolymer of a conjugated diene selected from the group consisting of isoprene, 1,3-butadiene, and mixtures thereof.

[0068] X is a coupling agent residue, wherein the coupling agent is selected from coupling agents known in the art, including polyalkenyl coupling agents, dihaloalkanes, silicon halides, siloxanes, multifunctional epoxides, silicon oxide compounds, esters of monohydric alcohols and carboxylic acids (such as methyl benzoate and dimethyl adipate) and epoxidized oils.

[0069] In some embodiments, SP is a hydrogenated sulfonated block copolymer having the following general structure: AB, ABA, (AB) n , (ABA) n , (ABA) n X, (AB) n X or a mixture thereof, wherein n is an integer from 2 to about 30, and X is a coupling agent residue. Prior to hydrogenation, each A block is a monoalkenyl aromatic polymer block and each B block is a controlled distribution copolymer block of at least one conjugated diene and at least one monoalkenyl aromatic hydrocarbon. After hydrogenation, approximately 0-10% of the aromatic double bonds have been reduced and at least about 90% of the conjugated diene double bonds have been reduced. The number average molecular weight of each A block is from about 3,000 to 60,000. The number average molecular weight of each B block is from about 30,000 to 300,000. Each B block comprises a terminal region adjacent to the A block rich in conjugated diene units and one or more regions not adjacent to the A block rich in monoalkenyl aromatic hydrocarbon units. The total amount of monoalkenyl aromatic hydrocarbon in the hydrogenated block copolymer is from about 20 to 80% by weight. The percentage of monoalkenyl arene in each B block is about 10-75 wt %; at least 25% of the aromatic rings of the alkenyl arene are sulfonated. The hydrogenated sulfonated block copolymer has an ionic conductivity greater than 0.08 Siemens / cm.

[0070] In some embodiments, the sulfonated copolymer is a sulfonated tetrafluoroethylene copolymer having a polytetrafluoroethylene (PTFE) backbone and vinyl ether side chains terminated with sulfonic acid groups in the cluster regions (e.g., -O-CF2-CF-O-CF2-CF2-).

[0071] In some embodiments, the sulfonated polymer is polystyrene sulfonate, examples of which include potassium polystyrene sulfonate, sodium polystyrene sulfonate, copolymers of sodium polystyrene sulfonate and potassium polystyrene sulfonate (e.g., polystyrene sulfonate copolymers) having molecular weights of >100,000 Daltons, >400,000 Daltons, and up to 1,500,000 Daltons. The polystyrene sulfonate polymer may be cross-linked or uncross-linked. In some embodiments, the polystyrene sulfonate polymer is uncross-linked and water-soluble.

[0072] In some embodiments, the sulfonated polymer is a polysulfone selected from the group consisting of aromatic polysulfones, polyphenylene sulfones, aromatic polyether sulfones, dichlorodiphenoxy sulfones, sulfonated substituted polysulfone polymers, and mixtures thereof. In some embodiments, the sulfonated polymer is a sulfonated polyether sulfone copolymer, which can be prepared from reactants including a sulfonate, such as potassium hydroquinone 2-sulfonate (HPS), and other monomers, such as bisphenol A and 4-fluorophenyl sulfone. The degree of sulfonation of the polymer can be controlled by the amount of HPS units in the polymer backbone.

[0073] In some embodiments, the sulfonated polymer is a polyaryletherketone, such as sulfonated polyetherketone (SPEEK), which is obtained by sulfonating polyetherketoneketone (PEKK). Polyetherketoneketone can be prepared using diphenyl ether and phenylenedicarbonic acid derivatives. Sulfonated PEEK is available as an alcohol and / or water-soluble product and is subsequently used for coating membranes, casting membranes, and thin films.

[0074] Using sulfonated copolymers, SP membranes are hydrophilic and hygroscopic, and are also permeable to water but impermeable to air and gases such as nitrogen and oxygen. Membranes containing sulfonated copolymers are characterized by selective permeation and ion exchange properties. SP membranes are also characterized by excellent water vapor transmission rate (MVTR) characteristics and excellent ion exchange capacity.

[0075] The SP membrane is also characterized in that it undergoes significant swelling when it absorbs water, e.g., at least 100% at ambient temperature. In embodiments using sulfonated block copolymers having a degree of sulfonation (e.g., at least 25 mol%), the SP membrane also exhibits antimicrobial properties and is particularly useful for disinfecting air in addition to cooling in indoor spaces.

[0076] In some embodiments, the SP has an IEC of >0.5 meq / g, or 1.5-3.5 meq / g, or >1.25 meq / g, or >2.2 meq / g, or >2.5 meq / g, or >4.0 meq / g, or <4.0 meq / g.

[0077] In some embodiments, the thickness of the SP membrane (thin film) or coating containing SP is >1 μm, or >5 μm, or 5-50 μm, or <100 μm, or <75 μm, or <μm. In some embodiments, the membrane / coating may comprise a nanocomposite material and may have an average pore size of <1 μm, or <0.5 μm, or <0.1 μm.

[0078] In use, moisture from the air can be extracted by the water permeable membrane by creating a pressure differential between the inlet side and the downstream end or section of the membrane module, which drives the diffusion of water molecules from the inlet side towards the other side of the membrane.

[0079] In some embodiments, the SP membrane can be in a form other than a sheet, such as a mesh, screen or grid, woven fabric, nonwoven fabric, perforated or apertured disc, foam, hollow fiber membrane, or a mat having interconnected voids and channels throughout the body, coated or bonded with the SP. In some embodiments, the SP membrane can be in a spiral form or arranged in a stack parallel or perpendicular to the direction of air flow.

[0080] In some embodiments, the SP membrane is in the form of a hollow fiber. Moist air flows through the hollow fibers under vacuum. The hollow fibers provide a large dehumidification surface area and can be oriented parallel or perpendicular to the airflow. When the interior of the hollow fiber membrane is placed under vacuum, an osmotic gradient is generated between the hollow core of each fiber (which is substantially under vacuum) and the outer surface of the fiber. In embodiments of hollow membranes, the SP coating or membrane can be applied to the inner surface, outer surface, or both the inner and outer surfaces of the hollow fibers. Hollow fiber membranes are known in the art and are disclosed, for example, in U.S. Patent No. 05762798, which is incorporated herein by reference.

[0081] The membrane may comprise SP bonded or incorporated into a frame, another membrane or membranes, a polymer matrix, or a plurality of fiber bundles by methods known in the art, such as casting. The SP membrane may also be applied as a coating to a fiber matrix or to fan blades in an evaporative cooler.

[0082] The membrane can be combined with a frame or other porous layer (serving as a carrier structure through which air and moisture can flow freely). The frame can comprise metal or plastic and can be formed into any conceivable geometric shape, including but not limited to honeycomb and corrugated structures. In some embodiments, the frame can have a honeycomb, spiral, non-woven or multiple porous designs to obtain a high surface area, wherein the proton conducting membrane is used on multiple sides and one side is an opening for air to flow in. In other embodiments, the frame is formed as a corrugated sheet with channels for increasing the exposed surface. Depending on, for example, the amount of moisture to be removed or the size of the room, the number of membrane frames can also be changed by adding or removing one or more frames.

[0083] The shape-retaining frame can be thermoformed or mechanically formed and is preferably rigid, semi-rigid or substantially rigid. As used herein, a rigid, semi-rigid or substantially rigid frame is a frame comprising a material or structure that can maintain its shape under its own weight. Suitable frame materials include fiberglass, aluminum, carbon, or rigid polymers based on polyester, polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, styrene / acrylonitrile / butadiene copolymers, nylon, polytetrafluoroethylene, polymer fibers based on aramid, metals, metal alloys, cellulose, nitrocellulose, cellulose acetate, and combinations thereof.

[0084] run:In some embodiments, an air cooling system facilitates cooling of air and / or removes moisture from the air with minimal energy consumption to reduce the humidity level in the air supplied to a room. To cool the air, the air cooling system includes an evaporator through which a liquid, such as water, flows, and a pressure reducer system having a liquid ejector and a booster pump to reduce the pressure within the evaporator. The pressure within the evaporator is reduced to a value equal to or greater than the saturated vapor pressure of the liquid at ambient temperature. As a result, the liquid is converted into vapor as it flows through the evaporator, absorbing the latent heat of evaporation from the air passing over the evaporator, thereby cooling the air.

[0085] In order to reduce the humidity level of the air, the air cooling system includes a dehumidification core having a membrane, which is suitable for promoting the removal of moisture from the air flowing through the air channel of the membrane. The membrane is selectively permeable to water and water vapor and impermeable to air. The dehumidification core is fluidly connected to a pressure reducer system to generate a vacuum inside the vapor channel of the membrane to extract moisture from the air flowing through the air channel of the membrane. Therefore, the pressure reducer system promotes the generation of a pressure difference between the air channel and the vapor channel of the dehumidification core to enable moisture to flow from the air channel to the vapor channel. In one embodiment, the pressure difference or vacuum can correspond to the saturated vapor pressure of water in the environment. In addition, the pressure reducer system is selectively connected to the evaporator and / or the dehumidification core.

[0086] To reduce the temperature of air supplied to a room or location, liquid is supplied from a liquid reservoir to an evaporator via an inlet conduit. The evaporator is then connected to a pressure reducer system to generate a pressure within the evaporator that is less than the saturated vapor pressure of the liquid at room temperature. To this end, a liquid ejector and, optionally, a booster pump are operated. To operate the liquid ejector, liquid is pumped from the liquid reservoir to the inlet portion of the liquid ejector. The liquid then enters the throat portion of the liquid ejector. Because the cross-sectional area or diameter of the throat portion is smaller than the cross-sectional area of ​​the inlet portion, the velocity of the liquid within the throat portion increases due to the Venturi effect. Consequently, the pressure within the throat portion decreases. Because the throat portion is connected to the booster pump and the evaporator, a corresponding low pressure is generated within the evaporator. It will be appreciated that the liquid ejector and / or booster pump are controlled so that the pressure within the evaporator is reduced to a value that is less than or equal to the saturated vapor pressure of the liquid at ambient temperature. As a result of the reduced pressure within the evaporator, at least a portion of the liquid flowing within the evaporator is converted into vapor. The evaporation of the liquid in the evaporator absorbs sensible heat from the ambient air passing over the exterior of the evaporator, thereby delivering cooled air to the room.

[0087] In some embodiments, the booster pump can be omitted. In such cases, the entire system is pre-conditioned at a pressure just above the saturated vapor pressure of the cooling / motive fluid before the system is turned on, and because it is a closed-loop system, the pre-conditioned pressure is maintained throughout the life of the system. In one embodiment, the air cooling system is pre-conditioned to a pressure 5-20% above the saturated vapor pressure of the liquid before startup. For example, when the motive fluid is water, the pressure inside the reservoir is reduced to 40-60 mbarA (when the liquid is water). After reducing the pressure inside the reservoir to the desired value, the motive fluid pump is operated to supply liquid to the liquid ejector, thereby moving material from the evaporator to the liquid reservoir through the liquid ejector. In this case, two things happen simultaneously: the pressure at the evaporator is further reduced to below the saturated vapor pressure of the liquid, causing the liquid to evaporate and absorb heat in the process. This evaporated fluid now condenses at the liquid ejector, increasing the liquid inventory in the liquid reservoir, thereby increasing the pressure in the reservoir and ejector system relative to the evaporator. In one embodiment, at least a portion of the liquid flowing from the liquid ejector to the reservoir is cooled by a heat exchanger. This process results in a higher efficiency vacuum pressure at the ejector, thus making the boost pump an optional component.

[0088] In embodiments for removing moisture from air to be delivered to a room or location, a pressure reducer system is connected to the vapor passage of the dehumidification core, and the reduced pressure increases the moisture gradient between the vacuum and ambient air sides, thereby accelerating the flux of moisture from the ambient to the vacuum medium and effectively dehumidifying the ambient air. It is known that moisture flux increases significantly when the pressure approaches and exceeds the critical saturation vapor pressure of water. The water vapor then flows to the throat portion of the liquid ejector and, due to the higher pressure within the outlet portion, is converted into liquid water within the outlet portion of the liquid ejector, which then flows back to the liquid reservoir. In some embodiments, at least a portion of the liquid flowing from the liquid ejector to the liquid reservoir is cooled by a heat exchanger.

[0089] Depending on the amount of cooling, water removal rate and / or the pressure of the liquid reservoir, the booster pump and the liquid ejector can be controlled to generate vacuum (i.e., pressure). For example, for large systems such as commercial air cooling systems, where a relatively large amount of cooling capacity is required, the water evaporation required will be proportionally improved, in which case the booster pump can promote the reduction of pressure to less than 10mbar. In such cases, a multi-stage or variable speed booster pump can be used. Alternatively, for small units that require a relatively smaller water vapor extraction rate and / or need to cool a smaller amount of air, a pressure corresponding to 10-20mbar is sufficient. In such cases, a single-stage booster pump can be used. In addition, the speed of the booster pump can be controlled to change the pressure in the vapor channel and / or the evaporator interior.

[0090] With reference to the accompanying drawings, various embodiments of the securing device and methods of using the same will be shown.

[0091] refer to Figure 1 , shows an air cooling system 100 having an evaporator 102 and a pressure reducer system 104 for reducing the pressure within the evaporator 102. The air cooling system 100 receives an inlet airflow (hereinafter referred to as a first airflow) 200A into a room and delivers or generates air having a relatively reduced temperature (hereinafter referred to as a second airflow 200B). As shown, the evaporator 102 is an evaporator coil 106 fluidly connected to the pressure reducer system 104 and a reservoir 108, such as a water reservoir 110 (for receiving a liquid, such as liquid water, from the reservoir 108). The reservoir 108 is a pressure-resistant reservoir and is suitable for holding a liquid at a pressure above atmospheric pressure and for storing the liquid at a relatively low pressure. For example, the reservoir 108 can store the liquid at a pressure equal to or less than the vapor pressure (i.e., saturated vapor pressure) of the liquid. In one embodiment, the liquid is water and has a vapor pressure of approximately 31.7 mbarA at 25°C. As shown, the inlet of the evaporator 102 is connected to the liquid reservoir 108 via an inlet conduit 112, while the outlet of the evaporator 102 is connected to the pressure reducer system 104 via an outlet conduit 114. Thus, liquid flows from the liquid reservoir 108 to the evaporator 102, is converted into vapor, such as water vapor, due to the low pressure or vacuum generated / created within the evaporator 102 by the pressure reducer system 104, and then flows back to the liquid reservoir 108 through the pressure reducer system 104. As the liquid is converted into vapor within the evaporator 102, the liquid receives the potential energy of conversion to vapor from the airflow 200A passing through the evaporator 102 and is thereby cooled. To facilitate the intake of the first airflow 200A and the passage of the first airflow 200A over the evaporator 102, the air cooling system 100 may include a fan 116 disposed downstream of the evaporator 102.

[0092] As shown, the pressure reducer system 104 includes a liquid ejector 120 , such as a water ejector 122 , fluidly connected to the outlet of the evaporator 102 , a pump 124 that supplies liquid, such as liquid water, to the liquid ejector 120 , and a liquid reservoir 108 that stores liquid and receives liquid discharged from the liquid ejector 120 .

[0093] As shown, the liquid ejector 120 is in fluid communication with the evaporator 102 via the outlet conduit 114. Thus, in response to the generation of a low pressure within the liquid ejector 120, vapor generated within the evaporator flows through the outlet conduit 114 toward the liquid ejector 120. As shown, the liquid ejector 120 includes an inlet portion 128 defining an inlet 130 of the liquid ejector 120, a throat portion 132 extending in a longitudinal direction from the inlet portion 128, and an outlet portion 134 extending from the throat portion 132 and defining an outlet 136 of the liquid ejector 120. Furthermore, the liquid ejector 120 defines a vapor inlet 138 that is fluidly connected to the evaporator 102 via the outlet conduit 114 and disposed in fluid communication with the throat portion 132 to facilitate the generation / maintenance of a relatively low pressure (i.e., vacuum) within the evaporator 102 and to facilitate the passage of vapor from the evaporator 102 into the interior of the liquid ejector 120 (i.e., the throat portion 132).

[0094] Furthermore, inlet portion 128 may include a nozzle portion 140 defining an orifice 142 for injecting / supplying liquid into throat portion 132 at a relatively high velocity, while the cross-sectional area of ​​outlet portion 134 gradually increases from throat portion 132 to outlet 136 to reduce the velocity of liquid received from throat portion 132. In some embodiments, the cross-sectional area of ​​inlet portion 128 may gradually decrease from inlet 130 to throat portion 132 to promote a gradual increase in the velocity / speed of the liquid. Thus, inlet portion 128 promotes an increase in the velocity / speed of the liquid as it flows from inlet 130 to throat portion 132, while outlet portion 134 is configured to reduce the velocity / speed of the liquid as it flows from throat portion 132 to outlet 136. Consequently, the pressure at throat portion 132 is lower relative to the pressures at inlet 130 and outlet 136. The pressure (i.e., vacuum) level at throat portion 132 can be adjusted / controlled by controlling the velocity and / or amount of liquid entering inlet portion 128. As such, the throat portion 132 is in fluid communication with the evaporator 102, thereby creating a vacuum (i.e., reduced pressure) within the evaporator 102. The pressure level at the throat portion 132 is controlled in such a manner that the reduced pressure created within the evaporator 102 is below a critical value. In one embodiment, when the liquid is liquid water, the critical value is less than or equal to the saturated vapor pressure of water at room temperature to achieve conversion of at least a portion of the liquid water received from the water reservoir 110 through the inlet conduit 112 into water vapor.

[0095] To generate and maintain a pressure within the evaporator 102 below a critical value, the pressure reducer system 104 may include a booster pump 148 disposed between the liquid ejector 120 and the evaporator 102. The booster pump 148 can further reduce the pressure within the evaporator 102, thereby increasing the vacuum. In one embodiment, the booster pump 148 and the liquid ejector 120 together reduce the pressure within the evaporator 102 by 20-40 mbarA. In one embodiment, the pressure reducer system 104 can generate a pressure of less than 20 mbarA at the inlet of the booster pump 148. In one embodiment, the pressure reducer system 104 can generate a pressure of less than 10 mbarA at the inlet of the booster pump 148. In one embodiment, the pressure reducer system 104 can generate a pressure of 10-20 mbarA at the inlet of the booster pump 148. Based on the size of the air cooling system 100 and the desired water extraction rate, the booster pump 148 and the liquid ejector 120 can be controlled to reduce the pressure within the evaporator 102. In one embodiment, the booster pump 148 is a Roots booster pump. However, it will be appreciated that any type of vacuum booster pump known in the art may be used.

[0096] In order to control and provide the flow of liquid to the liquid ejector 120, a pump 124 is disposed upstream of the liquid ejector 120 and is fluidly connected to the inlet 130 via a first tube 150. In one embodiment, the pump 124 can be a variable speed pump to allow control of the amount of liquid pumped to the liquid ejector 120. In addition, the pump 124 is connected to the reservoir 108 via a second tube 152 to receive liquid from the reservoir 108 and provide the liquid to the liquid ejector 120 at a desired rate / speed. In one embodiment, the reservoir 108 can include a plurality of fins (not shown) along the outer surface of the reservoir 108 to facilitate heat transfer between the liquid stored within the reservoir 108 and the environment. In some embodiments, the reservoir 108 is made of a material having a high thermal conductivity to facilitate heat transfer between the liquid stored within the reservoir 108 and the environment.

[0097] In some embodiments, at least a portion of the liquid exiting the liquid ejector 120 is cooled before being supplied to the liquid reservoir 108. To this end, the ejector 120 is fluidly connected to a heat exchanger 154 to cool (i.e., reduce the temperature) the liquid discharged from the liquid ejector 120. The heat exchanger 154 can be a gas-to-liquid heat exchanger and can be disposed downstream of the liquid ejector 120 and upstream of the liquid reservoir 108 and adapted to receive liquid from the liquid ejector 120 and supply cooled liquid to the liquid reservoir 108. As shown, the heat exchanger 154 is fluidly connected to the outlet 136 via a third conduit 158 ​​and receives liquid from the liquid ejector 120 via the third conduit 158. Similarly, the heat exchanger 154 is fluidly connected to the liquid reservoir 108 via a fourth conduit 160 and supplies cooled liquid to the liquid reservoir 108 via the fourth conduit 160. In some embodiments, only a portion of the liquid discharged from the liquid ejector 120 is provided to the heat exchanger 154 via a bypass conduit. In one embodiment, a portion of the liquid cooled by the heat exchanger 154 is mixed with the remaining portion of the liquid before the liquid enters the liquid reservoir 108. In some embodiments, a portion of the liquid cooled by the heat exchanger 154 can flow directly into / enter the liquid reservoir 108. In one embodiment, the pressure reducer system 104 can include a blower 162 to increase the flow of air toward the heat exchanger 154 to promote cooling of the liquid flowing through the heat exchanger 154. The blower 162 can be positioned upstream or downstream of the direction of air flow to the heat exchanger 154.

[0098] In operation, the vacuum generation capability of the ejector is only as good as the vapor pressure of the flowing fluid. Figure 1 , the flowing fluid in conduit 150 indicates how much vacuum the ejector can generate. At pump 124, if the pumping speed at pump 124 is increased, the pressure increases. As the vapor pressure of water approaches 40 mbar at one atmosphere, the ability to evacuate can be optimized if a high-pressure fluid is used (in other words, if the pump is pumped at a very high speed). Therefore, if the system is pressurized, a vacuum pressure of less than 40 mbar can be generated. In some embodiments, the pressure inside the tank is greater than the vapor pressure of the flowing fluid. If the fluid is water and the pressure is 1 atmosphere, the water reservoir needs to be > about 30 mbar. Using pump 124, the flowing fluid pressure increases significantly because the flowing fluid pressure drives the vacuum generation.

[0099] In some embodiments (not shown), the system further comprises (one or more) pressure monitoring devices, (one or more) controllers, etc., so that the speed is adjusted based on the pressure degree. It should be noted that the (relative) pressure can be less than 1 atmosphere. In some embodiments, the pressure at the water reservoir 110 is maintained at a level greater than the vapor pressure of the flowing fluid, thereby allowing the condensables from the coil to actually turn into liquid (condense). In turn, the pressure in the conduit 150 is maintained greater than the water reservoir, thereby creating an apparent vacuum in the coil. In some embodiments, a software program can be executed to monitor / adjust the feed to maintain conditions greater than and less than the vapor pressure of the flowing fluid. The use of a booster pump helps facilitate the operation of the system.

[0100] According to an alternative embodiment, such as Figure 2 As shown in FIG, the heat exchanger 154 is disposed downstream of the pump 124 rather than upstream of the reservoir 108 (e.g., FIG. Figure 1 108). In this case, a third conduit 158 ​​connects the liquid ejector 120 to the liquid reservoir 108. The heat exchanger 154 is adapted to cool at least a portion of the liquid pumped to the liquid ejector 120 by the pump 124. In this case, a portion of the fluid flowing on the conduit 150 is diverted to the conduit 161, downstream of the pump 124. This diverted fluid passes through the heat exchanger 154 and returns to the liquid reservoir 108 via the conduit 160. Furthermore, a blower 162 is shown disposed upstream of the heat exchanger 154 to facilitate the flow of air through the heat exchanger 154. However, the blower 162 may be disposed downstream of the heat exchanger.

[0101] In another embodiment, Figure 3 , the liquid reservoir 108 has an independent cooling system consisting of a liquid pump 124B, an air / liquid heat exchanger 154, and a fan 162. The system can be activated based on a comparison of the liquid temperature to a programmed set point. Figure 3 , heat exchanger 154 is connected to liquid reservoir 108 via inlet conduit 157 and outlet conduit 159, and second pump 124B supplies liquid from liquid reservoir 108 to heat exchanger 154 via inlet conduit 157 for cooling the liquid. The cooled liquid flows back to liquid reservoir 108 via outlet conduit 159. In one embodiment, second pump 124B pumps the liquid to heat exchanger 154 when the temperature of the liquid inside liquid reservoir 108 is greater than a critical temperature value. In addition, blower 162 is provided or placed upstream of heat exchanger 154 to allow air to flow through heat exchanger 154 for cooling the liquid. However, blower 162 may be placed downstream of heat exchanger 154.

[0102] The air cooling system 100 also includes a metering valve 166 to control the amount of liquid flowing from the liquid reservoir 108 to the evaporator 102. The metering valve 166 can be an electrically controlled valve and is controlled based on the temperature of the environment and / or the pressure generated within the evaporator 102. In one embodiment, the controller can control the boost pump 148, the pump 124, and the metering valve 166 to provide a desired level of air cooling.

[0103] In some embodiments, before starting the pump 124 that provides liquid from the reservoir 108 to the liquid ejector 120, the pressure inside the reservoir 108 is reduced by engaging a vacuum pump (not shown) with the reservoir 108. In some embodiments, the pressure inside the reservoir 108 is reduced to a value that is 5-20% greater than the saturated vapor pressure of the liquid at ambient temperature. The pressure inside the reservoir 108 is reduced to a value that depends on the saturated vapor pressure of the liquid at ambient temperature, for example, a value of 40-150 mbarA in embodiments using water. After reducing the pressure inside the reservoir 108 to the desired value, the pump 124 is operated to provide liquid to the liquid ejector 120. Because the liquid leaving the liquid ejector 120 will have a higher pressure than the liquid entering the liquid ejector 120, the pressure inside the reservoir 108 increases, thereby causing the pressure of the liquid delivered to the liquid ejector 120 by the pump 124 to increase. This results in a higher pressure reduction at the throat portion 132, resulting in the desired lower pressure inside the evaporator 102. In this manner, the liquid ejector facilitates generating a pressure within the evaporator 102 that is less than or equal to the saturated vapor pressure of the liquid at ambient temperature. In some embodiments, this facilitates limiting the use of the boost pump 148. In some embodiments, the boost pump 148 may be omitted.

[0104] refer to Figure 4 , an air cooling system 100' is shown according to an alternative embodiment of the present disclosure. Air cooling system 100' is similar to air cooling system 100, except that air cooling system 100' additionally includes a dehumidification core 210 fluidly connected to the pressure reducer system 104 to facilitate the extraction of moisture from the air, thereby facilitating the control of the moisture or humidity level in the air delivered to the room or place (second airflow 200B). Thus, the dehumidification core 210 receives air with a relatively high moisture content (also referred to as inlet air 400A) and discharges air with a relatively low moisture content (also referred to as outlet air 400B). Due to the pressure difference between the channels, a moisture gradient is generated as the moisture content decreases in the lower pressure environment, thereby accelerating the flux.

[0105] For this purpose, refer to Figure 4 、 5, 6, and 7, the dehumidification core 210 defines at least one air channel 214 through which the air 400A flows and at least one vapor channel 216 that receives moisture (e.g., water vapor 220 extracted from the inlet air 400A) flowing through the at least one air channel 214. As shown, each vapor channel 216 is disposed adjacent to one or more of the air channels 214 and is separated by a membrane 222. Conversely, each air channel 214 is disposed adjacent to one or more of the vapor channels 216 and is separated from adjacent vapor channels 216 by a membrane 222.

[0106] In some embodiments, as Figure 6 , the dehumidification core 210 has a box structure having a first face 226 disposed substantially perpendicular to the flow of inlet air 400A and defining an inlet 228 of each air channel 214, and a second face 230 disposed substantially parallel to the first face 226 and defining an outlet 232 of each air channel 214. Thus, inlet air 400A enters the air channel 214 through the first face 226 and exits the dehumidification core 210 as outlet air 400B through the second face 230. The moisture thus removed from the inlet air 400A (i.e., water vapor 220) is collected in the vapor channel 216 (e.g., Figure 5 (displayed in the middle).

[0107] As shown, each vapor channel 216 can extend in a direction substantially perpendicular to the direction in which the air channel 214 extends, and can extend in a direction substantially perpendicular to the third side 234 (i.e., top side 234) of the dehumidification core 210 and the fourth side 236 (i.e., bottom side 236) of the dehumidification core 210. In addition, the fourth side 236 can define a closed end of each vapor channel 214, thereby preventing water vapor 220 from escaping from the dehumidification core 210 through the bottom side 236, while the outlet 238 (i.e., bottom side 236) of each vapor channel 214 can be opened. Figure 7 236 ). In some embodiments, the one or more collection channels (not shown) can extend substantially parallel to the air channel 214 and can include closed ends at the first side 226 and the second side 230.

[0108] In addition, if Figure 6 and Figure 7As shown in FIG, the dehumidification core 210 is formed by arranging a plurality of stacks 241 so that the stacks 241 are arranged in parallel and spaced apart from each other to define an air channel 214 between them. The stacks 241 are arranged so that the membrane 222 of one stack 241 faces the membrane 222 of the adjacent stack 241. In addition, each stack 241 includes an outer frame 242 and a corrugated structure 243 arranged inside the outer frame 242 and supported by the outer frame 242. As shown, the outer frame 242 is connected to the outer edge of the corrugated structure 243. In addition, each corrugated structure 243 defines a plurality of vapor channels 216 having a substantially rectangular shape. In addition, each corrugated structure 243 includes two membranes 222, one membrane 222 is arranged on a first side of the corrugated structure 243 and the other membrane 222 is arranged on a second side of the corrugated structure 143 opposite to the first side. Therefore, the corrugated structure 243 is arranged between the two membranes 222. Thus, the membrane 222 separates the vapor channels 216 of the corrugated structure 243 from the air channels 214 defined between two adjacent stacks 241 .

[0109] While a box, such as a cubic structure having vapor channels 216 extending substantially perpendicular to the air channels 214, is contemplated, it is understood that the dehumidification core 210 may include any other suitable shape or structure known in the art. Furthermore, it is contemplated that the air channels 214 and vapor channels 216 may extend substantially in the same direction and may run parallel to each other. Furthermore, a dehumidification core 210 having concentric air channels 214 and vapor channels 216 is also contemplated. Furthermore, the dehumidification core 210 may include a conduit 240 ( Figure 4 and 6 ) to receive water vapor 220 and promote the water vapor 220 to leave the dehumidification core 210.

[0110] like Figure 5 216, while the flow of other components 244 of the air, such as nitrogen, oxygen, carbon dioxide, etc., from the air channels 214 to the vapor channels 216 is substantially blocked by the membrane 222. In some embodiments, the membrane 222 can block approximately 99% of the flow of the other components 244 from the air channels 214 to the vapor channels 216. In certain embodiments, the membrane 222 can block approximately 95-99% of the flow of the other components 244 from the air channels 214 to the vapor channels 216.

[0111] The membrane 222 facilitates the extraction of water vapor 220 from the air flowing through the air channel 214 and the flow of the water vapor 220 through the membrane 220 into the adjacent vapor channel 216 because the pressure inside the vapor channel 216 is relatively lower than that inside the air channel 214. In this way, a humidity gradient is established between the air channel 214 and the adjacent vapor channel 216. The humidity gradient is generated by generating a pressure gradient / pressure difference between the air channel 214 and the adjacent vapor channel 216. Specifically, the partial pressure of the water vapor inside the vapor channel 216 is maintained at a level lower than the partial pressure of the water vapor inside the air channel 214, so as to promote the water vapor 220 in the air flowing through the air channel 214 to flow toward the suction side (i.e., the vapor channel 216).

[0112] Conduit 240 facilitates connection of the reducer system 104 to the vapor passage 216 and facilitates maintaining a desired reduced pressure within the vapor passage 216 to create a desired pressure differential between the vapor passage 216 and the air passage 214. As with the evaporator 102, the reducer system 104 (i.e., the liquid ejector 120 and the booster pump 148) generates a pressure within the vapor passage 216 corresponding to the saturated vapor pressure of a liquid, such as water, at ambient temperature. In one embodiment, the booster pump 148 and the water ejector 122 together reduce the pressure within the vapor passage 216 by 20-40 mbarA. In one embodiment, the reducer system 104 can generate a pressure of less than 20 mbarA at the inlet of the booster pump 148. In one embodiment, the reducer system 104 can generate a pressure of less than 10 mbarA at the inlet of the booster pump 148. In one embodiment, the reducer system 104 can generate a pressure of 10-20 mbarA at the inlet of the booster pump 148. Based on the size of the air cooling system 100 ′ and the desired water extraction rate, the booster pump 148 and the water ejector 122 may be controlled to reduce the pressure inside the vapor path.

[0113] In addition, the air cooling system 100' includes at least one valve, such as a first valve 170 and a second valve 180, to facilitate selective connection of the evaporator 102 and / or the dehumidification core 210 with the pressure reducer system 104. As shown, the first valve 170 is provided to control connection or disconnection of the evaporator 102 from the pressure reducer system 104 and is adapted to move between a first position and a second position. In the first position, the first valve 170 allows fluid connection of the evaporator 102 with the pressure reducer system 104 and allows vapor to flow from the evaporator to the liquid ejector 120, while in the second position, the first valve 170 fluidly disconnects the evaporator 102 from the pressure reducer system 104 and thereby prevents vapor from flowing from the evaporator 102 to the liquid ejector 120. As shown, the first valve 170 is provided upstream of the pressure reducer system 104 and downstream of the evaporator 102.

[0114] Similarly, a second valve 180 is provided to control the connection or disconnection of the dehumidification core 210 from the pressure reducer system 104 and is adapted to move between an open position and a closed position. In the open position, the second valve 180 allows fluid connection of the vapor channel 216 with the pressure reducer system 104 and allows the flow of water vapor 220 from the vapor channel 216 to the liquid ejector 120. In the closed position, the second valve 180 fluidly disconnects the vapor channel 216 from the pressure reducer system 104 and thereby prevents the flow of water vapor 220 from the vapor channel 216 to the liquid ejector 120. As shown, the second valve 180 is positioned upstream of the pressure reducer system 104 and downstream of the dehumidification core 210. In some embodiments, the first valve 170 and the second valve 180 are electrically controlled valves and are operated by a controller based on the desired cooling and humidity levels of the air received from the room. In some cases, only the evaporator 102 is fluidly connected to the pressure reducer system 104 by moving the first valve 170 to the first position and the second valve 180 to the closed position. Similarly, only the dehumidification core 210 can be fluidly connected to the pressure reducer system 104 by moving the second valve 180 to the open position and moving the first valve 170 to the second position. In addition, to simultaneously connect the evaporator 102 and the dehumidification core 210 to the pressure reducer system 104, the first valve 170 is moved to the first position and the second valve 180 is moved to the open position.

[0115] Furthermore, in some embodiments, the air cooling system 100' may include a controller and a plurality of sensors to control the operation of the air cooling system 100'. In some embodiments, the air cooling system 100' may include one or more temperature sensors and one or more humidity sensors to monitor the temperature and humidity of at least one of the first air flow 200A, the inlet air 400A, the outlet air 400B, and the second air flow 200B. Accordingly, the controller may control the pump 124 to deliver liquid at an optimal rate to maintain and control the boost pump 148 to maintain or generate a desired level of vacuum or pressure within the vapor channel 216 and / or the evaporator 102.

[0116] While an air cooling system 100' is shown and considered to have a single evaporator 102 and a single dehumidification core 210, it is understood that the air cooling system 100' may include any number of dehumidification cores 210 and evaporators 102 arranged in a series or parallel configuration, or a combination thereof.

[0117] The operation of the air cooling system 100', which has a dehumidification core 210 and an evaporator 102 fluidically connected to the pressure reducer system 104, will now be explained. To this end, the first valve 170 is moved to the first position and the second valve 180 is moved to the open position. The air cooling system 100' receives a first airflow 200A having a relatively high humidity level and a higher temperature from a room and supplies a second airflow 200B having a relatively low humidity level and a lower temperature to the room. To this end, the air cooling system 100' receives the first airflow 200A from the room. In some embodiments, the fan 116 can facilitate the inhalation / intake of the first airflow 200A from the room. Upon entering the first device 700, the first airflow 200A enters the dehumidification core 210 as inlet air 400A, flows through the air channels 214, and exits the dehumidification core 210 as outlet air 400B. As the inlet air 400A flows through the air channels 214, at least a portion of the water vapor 220 present in the inlet air 400A flows through the membrane 222 and settles within the adjacent vapor channels 216. To facilitate the extraction of water vapor 220 from inlet air 400A and the movement of water vapor 220 within vapor channel 216, a pressure differential is generated. The pressure differential is generated by creating or maintaining a relatively lower pressure within vapor channel 216 compared to the pressure within air channel 214. In fact, to ensure the flow of water vapor 220 across membrane 222, the partial pressure of water vapor within vapor channel 216 is maintained at a lower value relative to the saturated vapor pressure of water at the ambient temperature within air channel 214. To this end, the controller can control and operate pump 124 to pump liquid (in this case, liquid water) from liquid reservoir 108 to inlet 130 of liquid ejector 120 (in this case, water ejector 122) at an appropriate rate (i.e., a predetermined amount of liquid water entering inlet portion 128 per second) and operate and control booster pump 148. The appropriate velocity of liquid water entering the water ejector 122 and the speed of the booster pump 148 may be determined based on the humidity level of the room and / or the humidity level of the inlet air 400A, the temperature of the inlet air 400A, the desired temperature and humidity level of the air delivered to the room, and / or the velocity and amount of the first air flow 200A entering the air cooling system 100 ′.

[0118] As the liquid water flows through inlet portion 128 and enters throat portion 132, the velocity of the liquid water increases, reaching a maximum value at throat portion 132. Consequently, a relatively low pressure (i.e., a vacuum) is generated in throat portion 132, and thus, a relatively low pressure is generated within vapor channel 216 as vapor channel 216 is fluidly connected to throat portion 132 via vapor inlet 138 and conduit 240. It will be appreciated that due to vacuum losses caused by the length of conduit 240 and any other bends in conduit 240, the pressure within vapor channel 216 may be relatively higher than the pressure at the outlet of booster pump 148. Furthermore, the pressure reducer system 104 is controlled so that the pressure at the outlet of booster pump 148 is lower than the pressure within air channel 214 and at a desired pressure differential. Due to the pressure differential between vapor channel 216 and air channel 214, water vapor 220 is extracted from the air flowing through air channel 214 and moves across membrane 222 into vapor channel 216. Similarly, water vapor 220 extracted from inlet air 400A can move / flow through conduit 240 and booster pump 148 and enter throat section 132 through vapor inlet 138 due to the pressure differential between vapor passage 216 and throat section 132. Upon entering water ejector 122 (i.e., throat section 132), water vapor 220 can move along with liquid water and enter outlet section 134 of water ejector 122. Due to the increased cross-sectional area in outlet section 134, the velocity of the liquid water decreases, thereby generating a relatively high pressure within outlet section 134 compared to the pressure within throat section 132. Consequently, water vapor 220 received from vapor passage 216 condenses within outlet section 134 before exiting water ejector 122. Consequently, a separate condenser for condensing water vapor 220 into liquid water is no longer required, thereby improving the efficiency of air cooling system 100'.

[0119] Due to the condensation of water vapor 220 within the outlet portion 134 of the water ejector 122, heat may be generated, thereby causing the temperature of the liquid water exiting the outlet 136 of the water ejector 122 to increase. To reduce the temperature of the liquid water before delivering it to the water reservoir 110, at least a portion of the liquid water is directed to a heat exchanger 154, which facilitates cooling of the received liquid water. Thereafter, the cooled liquid water is supplied to the water reservoir 110 for storage and available for subsequent supply to the water ejector 122 via the pump 124. It may be noted that due to the condensation of water vapor 220 received from the dehumidification core 210, the volume of liquid water exiting the water ejector 122 and received by the water reservoir 110 may be higher than the volume of liquid water supplied to the water ejector 122 via the pump 124. Consequently, the level of liquid water within the water reservoir 110 may increase. To prevent overflow of the water reservoir 110 and liquid water from spilling out of the water reservoir 110, the drain valve 182 can be opened when the liquid water level in the water reservoir 110 is greater than a first critical level. Opening the drain valve 182 allows the liquid water to drain from the water reservoir 110. Furthermore, the drain valve 182 can be closed in response to the liquid water level falling below a second critical level. In certain embodiments, the drain valve 182 is adapted to automatically open and close in response to the liquid water level reaching above the first critical level and falling below the second critical level, respectively.

[0120] Although not in Figures 1 to 3 , but in some embodiments, the air cooling system 100 also has a drain valve to facilitate draining / removal of liquid from the reservoir 108.

[0121] Furthermore, outlet air 400B discharged from the dehumidification core 210 is received by the evaporator 102, cooled, and exits the evaporator 102 as a second airflow 200B. As the outlet air 400B passes through the evaporator 102, due to the low pressure generated within the evaporator coil 106 by the water ejectors 122 and the latent heat provided by the outlet air 400B, the outlet air 400B can cause the liquid water flowing within the evaporator coil 106 to evaporate, thereby converting at least a portion of the liquid water flowing within the evaporator coil 106 into water vapor. Consequently, the temperature of the outlet air 400B decreases as it passes through the evaporator 102. Consequently, the second airflow 200B discharged from the evaporator is cooler than the outlet air 400B received from the dehumidification core 210. After passing through the evaporator 102, the second airflow 200B exits the air cooling system 100' and enters the room. Due to the incompressible nature of liquid water, using liquid water as the motive fluid to generate the low pressure within the throat portion 132, and therefore within the vapor passage 216, helps reduce energy consumption. Furthermore, using water emitters 122 as pressure relief devices prevents damage associated with cavitation, compared to using conventional pumps to create a low pressure or vacuum in vapor passage 216. Furthermore, using water emitters 122 helps reduce the overall size of the air cooling system. When the second valve is moved to the closed position, the dehumidification core 210 is disconnected, and the air cooling system 100' cools only the first airflow 200A and provides cooled air to the room. Therefore, in this case, the air cooling system 100' can operate in the same manner as the air cooling system 100. Alternatively, the second valve 180 can be moved to the open position and the first valve 170 to the second position. In this case, the evaporator 102 is disconnected from the air cooling system 100', and the air cooling system 100' promotes the removal of moisture from the first airflow 200A. Consequently, the second airflow 200B delivered to the room has a lower humidity level than the first airflow 200A.

[0122] The use of the water ejector 122 provides the ability to process a highly condensable fraction in the form of water vapor and to generate a fresh water source when it condenses the moisture extracted at the dehumidification core 210. Furthermore, the water ejector 122 is capable of generating a vacuum pressure as low as 5 mbar absolute (expressed as mbarA). Furthermore, the water ejector 122 and the booster pump 148 can be adjusted to operate over a range of vacuum pressures, such as 100 mbarA, 150 mbarA, or even 500 mbarA or greater. The vacuum pressure is adjusted by adjusting fluid variables such as pressure and flow rate.

[0123] As used herein, the term "includes" and its grammatical variations are intended to be non-limiting, such that the recitation of items in a list does not exclude other like items that can be substituted or added to the listed items. When used in this specification, the terms "includes" and / or "comprising" specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

Claims

1. An air cooling system (100, 100'), comprising: an evaporator (102), the evaporator being adapted to cool air passing through the evaporator; a liquid reservoir (108) for storing liquid and being fluidically connected to the evaporator and providing the liquid to the evaporator; and A pressure reducer system (104) is fluidically connected to the evaporator and is adapted to generate a pressure inside the evaporator that is less than or equal to the saturated vapor pressure of the liquid at ambient temperature to promote conversion of at least a portion of the liquid flowing through the evaporator into vapor, the pressure reducer system comprising a liquid ejector (120), the liquid ejector (120) having: an inlet portion (128) adapted to receive liquid from the reservoir; a throat portion (132) disposed downstream of the inlet portion and fluidly connected to the evaporator, wherein the throat portion is adapted to increase the velocity of liquid received from the inlet portion; and an outlet portion (134) disposed downstream of the throat portion and configured to increase the pressure within the liquid ejector to promote condensation of vapor received from the evaporator; and A pump (124) is fluidly connected to the liquid ejector and the liquid reservoir and is configured to supply liquid from the liquid reservoir to the liquid ejector.

2. The air cooling system according to claim 1 , wherein the pressure reducer system further comprises a booster pump (148) disposed upstream of the liquid ejector and fluidically connected to the evaporator to reduce the pressure inside the evaporator to a pressure less than the saturated vapor pressure of the liquid.

3. The air cooling system according to claim 2, wherein the liquid is water and the booster pump facilitates reducing the pressure to a value less than or equal to 31.7 mbarA at 25°C.

4. The air cooling system according to claim 2, wherein the booster pump (148) facilitates reducing the pressure to a value less than the saturated vapor pressure of the liquid in the evaporator, or a value of 20-40 mbarA or 10-20 mbarA.

5. The air cooling system of claim 1, wherein the reservoir (108) includes a drain valve (182) for facilitating drainage of the liquid from the reservoir when the level of the liquid within the reservoir reaches above a first critical level.

6. The air cooling system of claim 1, further comprising a heat exchanger (154) fluidly connected to the liquid ejector and configured to receive at least a portion of the liquid exiting the liquid ejector, wherein the heat exchanger is configured to cool the received liquid.

7. The air cooling system according to claim 6, wherein a heat exchanger (154) is provided upstream of the liquid reservoir and supplies the cooled liquid to the liquid reservoir.

8. The air cooling system of claim 1 , wherein the liquid ejector ( 120 ) is a water ejector adapted to receive liquid water from a pump, and wherein the system further comprises a metering valve ( 166 ) disposed between the liquid reservoir and the evaporator to control the flow of the liquid from the liquid reservoir to the evaporator.

9. The air cooling system according to claim 1, further comprising a dehumidification core (210), the dehumidification core being disposed upstream or downstream of the evaporator and being adapted to be fluidically connected to the liquid ejector, the dehumidification core comprising: air passage (214), at least one vapor channel (216) separate from the air channel, and a membrane (222) separating the at least one vapor channel from the air channel and adapted to facilitate the removal of moisture from air flowing through the air channel, wherein the membrane is selectively permeable to water and water vapor and impermeable to air and has an ion exchange capacity of at least 1.0 milliequivalents / gram, wherein the throat portion is fluidly connected to the at least one vapor channel to generate a relatively lower pressure in the at least one vapor channel than in the air channel to promote the flow of moisture from the air flowing through the air channel to the at least one vapor channel, and The outlet portion promotes condensation of water vapor received from the at least one vapor channel.

10. The air cooling system according to claim 9, wherein the pressure reducer system (104) further comprises a booster pump (148) disposed upstream of the liquid ejector and connected to the dehumidification core fluid to reduce the pressure inside the at least one vapor channel to a pressure lower than the saturated vapor pressure of water.

11. The air cooling system according to claim 9, further comprising a valve (170, 180) disposed between the pressure reducer system and the dehumidification core to control the fluid connection between the dehumidification core and the pressure reducer system.

12. The air cooling system of claim 9, wherein the membrane (222) comprises a sulfonated polymer.

13. The air cooling system according to claim 1 , wherein upon starting the air cooling system, the pressure inside the liquid reservoir ( 108 ) is reduced to a value that is 5-20% greater than the saturated vapor pressure of the liquid at ambient temperature; or when the liquid is water, upon starting the air cooling system, the pressure inside the liquid reservoir is reduced to a value that is 40-150 mbarA.

14. The air cooling system according to claim 1, wherein before startup, the air cooling system (100, 100') is pre-adjusted to a pressure value that is 5-20% greater than the saturated vapor pressure of the liquid.

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