Dehumidifier and membrane filter element thereof

Abstract

A membrane cartridge for a dehumidification apparatus has a cartridge frame having an interior cavity and opposing face openings in fluid communication with the interior cavity. The frame has an edge having an edge opening in fluid communication with the interior cavity and the face opening. An insert having a perforated surface aligned with the face opening is defined by a boundary adjacent the face opening. A membrane is attached to the cartridge frame over the insert and the face opening, the membrane being sealed with respect to the face opening. A dehumidification apparatus that may employ the membrane cartridge has a housing having an opening through which a flow of gas is allowed, where the membrane cartridge is parallel to the flow of gas. A compressible seal is located between the edge of the frame and the housing, and a fastener located between the housing and the membrane cartridge is configured to pull the membrane cartridge toward the housing to compress the seal.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. USSN 63 / 406,426, filed on September 14, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to dehumidification of gas streams, and in particular to a dehumidification device and a membrane filter element that can be used in the dehumidification device. Background Art

[0004] Graphene oxide (GO) membranes are selectively permeable to water, which makes GO membranes attractive for water separation applications such as dehumidification of air streams. However, the fragility of GO membranes poses a challenge to utilizing GO membranes in commercial dehumidification devices.

[0005] There remains a need for dehumidifiers and membrane cartridges that can successfully utilize GO membranes to dehumidify air streams. Summary of the invention

[0006] A membrane filter element for a dehumidification device comprises: a filter element frame, the filter element frame having an internal cavity and having a first face opening and a second face opening in fluid communication with the internal cavity, the filter element frame further having an edge, the edge comprising one or more edge openings in fluid communication with the internal cavity and the two face openings; a first insert, the first insert comprising a first perforated surface aligned with the first face opening, the first perforated surface being defined by a first boundary adjacent to the first face opening; a second insert, the second insert comprising a second perforated surface aligned with the second face opening, the second perforated surface being defined by a second boundary adjacent to the second face opening; a first membrane, the first membrane being attached to the filter element frame above the first insert and the first face opening, the first membrane being sealed relative to the first face opening; and a second membrane, the second membrane being attached to the filter element frame above the second insert and the second face opening, the second membrane being sealed relative to the second face opening.

[0007] A dehumidification device comprises: a shell having an opening allowing gas to flow therethrough; a membrane filter element parallel to the gas flow, the membrane filter element having an edge adjacent to the shell; a compressible seal located between the edge of the membrane filter element and the shell; and a fastener located between the shell and the membrane filter element, the fastener being configured to pull the membrane filter element toward the shell to compress the seal.

[0008] A dehumidifier system comprises the dehumidification device described above and / or the membrane filter element described above.

[0009] The membrane filter element includes a filter element frame. The filter element frame can be any suitable peripheral shape suitable for the dehumidifier. For example, the filter element frame can be polygonal (e.g., rectangular, square, etc.), circular or elliptical. Many dehumidifiers are suitable for rectangular membrane filters; therefore, the filter element frame is preferably rectangular. Due to the thickness of the filter element frame; therefore, the peripheral frame element of the filter element frame defines a volume defined by the internal length and width of the frame element and the thickness of the frame. The defined volume is an internal cavity surrounded by the filter element frame and the openings on the opposite faces of the filter element frame.

[0010] The filter element frame includes an edge, which includes one or more edge openings in fluid communication with the internal cavity and the two face openings. The edge openings are through holes that connect the internal cavity fluid to the exterior surrounding the membrane filter element. Fluid (e.g., water vapor and condensed water) collected in the internal cavity during operation of the membrane filter element in the dehumidifier is discharged from the interior through the one or more edge openings. The edge of the filter element frame may also include one or more locating holes that can be aligned with corresponding one or more indexing pins on the dehumidifier to properly align the membrane filter element when the membrane filter element is installed in the dehumidifier. In some embodiments, the edge opening and the locating hole are located on the same edge of the filter element frame.

[0011] A semipermeable membrane, such as a graphene oxide membrane, covers each face opening of the filter cartridge frame, thereby closing the internal cavity. The membrane is attached and sealed to the filter cartridge frame. The membrane can be attached to the frame by any suitable method, for example, by an adhesive, with a clamp, with staples, with screws, etc. The membrane can be sealed to the frame by one or more seals (e.g., gaskets, etc.) or by a sealant (e.g., an adhesive, a caulking agent, etc.). Preferably, the membrane is attached and sealed to the frame by an adhesive. The adhesive is preferably insoluble in water. Epoxy-based adhesives are particularly preferred.

[0012] Because the membrane is flexible and somewhat fragile, each of the membranes is supported by a corresponding insert disposed between two membranes in the internal cavity and aligned with the face opening. The insert has a perforated surface to allow fluids (e.g., water vapor and condensed water) that pass through the membrane from the outside of the internal cavity to enter the internal cavity. The insert has a peripheral boundary disposed adjacent to the face opening. The boundary of the insert is a peripheral portion that is substantially free of protrusions, such as perforations, pins, and struts that decorate most of the interior-facing surfaces of the insert. The inserts can be attached to each other in the internal cavity, to the filter element frame, to the filter element frame and to each other, or not attached to anything but held in place by the membrane.

[0013] The inserts may be attached to each other in one or more ways, for example, the inserts may be glued together, screwed together, clamped together, or some combination thereof. In some embodiments, the inserts are clamped together. In some embodiments, a snap-on locking mechanism may be used to achieve clamping. In some embodiments, the snap-on locking mechanism comprises a plurality of pins and corresponding plurality of receiving holes, the plurality of pins extending from a perforated surface of one or both of the inserts into an internal cavity, the plurality of receiving holes being located on one or both of the opposing inserts, whereby the plurality of pins are inserted and fixed in the receiving holes. The pins may extend from one of the inserts into a receiving hole on the other insert, or both inserts may have pins and receiving holes corresponding to the receiving holes and pins on the other insert. In some embodiments, the receiving holes may be formed as a plurality of struts extending from a perforated surface of one or both of the inserts into the internal cavity. The pins may be provided with a head, the size and shape of which is set to be pushed into the receiving hole, the size and shape of the receiving hole being set to allow the pin to be inserted while preventing or inhibiting the pin from being pulled out after it has been inserted.

[0014] The insert may not be attached to the filter cartridge frame, or may be attached to the filter cartridge frame in one or more ways, such as with an adhesive, screws, nails, rivets, clamps, or some combination thereof. In addition, the filter cartridge frame may be configured to engage with the insert in one or more different ways. In some embodiments, the filter cartridge frame includes one or more recesses, and the borders of one or both inserts engage with the one or more recesses. The filter cartridge frame may include a recess adjacent to one or both of the face openings. In some embodiments, the recess periphery engages with the border of one of the inserts. In some embodiments, one or both of the membranes may be provided with a membrane frame attached to the filter cartridge frame. The membrane frame may have an outer lip that accommodates the insert when the insert is placed on a frame element of the filter cartridge frame. Thus, the border can be flush with the filter cartridge frame without the need for a recess in the filter cartridge frame while still remaining below the membrane above the face opening.

[0015] The membrane cartridge allows the use of graphene oxide (GO) membranes in dehumidification equipment to separate water vapor from a gas (eg, air) stream. In some embodiments, one or both of the membranes may be graphene oxide.

[0016] The dehumidification device includes a housing. The housing may include various walls, including, for example, a vacuum plate, a side plate, a guide plate, and a cover. The housing preferably has an opening, preferably a relative opening, through which a gas (e.g., humid air) is directed during operation of the device. At least one membrane filter element, preferably a plurality of membrane filter elements, is arranged in the housing so that the gas flow passes through the surface of the membrane, that is, the membrane filter element is parallel to the gas flow. A plurality of membrane filter elements are preferably organized in a filter element assembly, wherein the membrane filter elements are arranged parallel to each other, wherein there is a gas flow channel between the membrane filter elements. The gas flow channel preferably has the same width and profile so that water vapor penetrates the membrane filter element uniformly through the filter element assembly. The air flow through the housing through the membrane filter element can be achieved using any suitable device (e.g., a fan), which can be installed on the device or as part of a larger dehumidification system.

[0017] The water vapor and any condensed water collected in the interior of the membrane filter element can be discharged through one or more edge openings in the membrane filter element. To assist in drainage, the device preferably includes a vacuum system in fluid communication with the interior of the membrane filter element. In some embodiments, the vacuum system includes a vacuum chamber, such as a vacuum manifold, which is in fluid communication with the edge of the membrane filter element, specifically in fluid communication with one or more edge openings of the membrane filter element, wherein the one or more edge openings provide through holes that connect the interior fluid of the membrane filter element to the vacuum chamber.

[0018] A vacuum plate forming a portion of the bottom of the housing, preferably the housing, can serve as an interface between the vacuum chamber and the membrane filter element. The membrane filter element is preferably mounted on the housing, preferably on the vacuum plate, so that the edge of the membrane filter element is adjacent to the housing, especially adjacent to the vacuum plate. In some embodiments, the vacuum plate includes one or more vacuum channels aligned with the edge opening of the membrane filter element, thereby providing support for the membrane filter element and providing a fluid connection with the vacuum chamber. An airtight fluid seal can be provided between the vacuum chamber and the vacuum plate and between the vacuum plate and the edge of the membrane filter element. In particular, the seal between the vacuum plate and the edge of the membrane filter element is compressible, so pulling the membrane filter element toward the housing, preferably the vacuum plate, will compress the seal to provide a better seal. One or more fasteners between the membrane filter element and the housing, for example, bolts, clamps, etc., can be used to pull the membrane filter element toward the housing to compress the seal. In some embodiments, one or more fasteners are positioned in the vacuum chamber.

[0019] In order to properly mount and place the membrane filter element on its edge in the housing, the housing preferably includes one or more indexing pins. One or more indexing pins engage positioning holes in the edge of the membrane filter element. When the device includes multiple membrane filter elements, the housing includes multiple indexing pins to help place the membrane filter elements parallel to each other in the stack of filter elements in the device. The indexing pins are preferably positioned on the upper surface of the vacuum plate. In some embodiments, a guide plate positioned at the edge of the membrane filter element opposite to the edge opening is used to assist in the proper placement of the membrane filter element. In addition, when multiple membrane filter elements are utilized, the device may include filter element spacers for properly spacing the membrane filter elements apart so that the membrane filter elements are parallel to each other and ideally spaced apart.

[0020] In some embodiments, one or more of the membrane filter elements are membrane filter elements as defined above.The edge of the membrane filter element is an edge of the filter element frame comprising one or more edge openings.

[0021] Other features will be described or will become apparent during the following detailed description. It should be understood that each feature described herein can be utilized in combination with any one or more of the other described features, and each feature is not necessarily dependent on the presence of another feature, unless it is obvious to those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] For a clearer understanding, preferred embodiments will now be described in detail by way of example with reference to the accompanying drawings, in which:

[0023] Figure 1A An exploded view of a first embodiment of a membrane cartridge is depicted.

[0024] Figure 1B Depicted Figure 1A Perspective view of a membrane filter element.

[0025] Figure 1C Depicted Figure 1B Cross section of a membrane filter element.

[0026] Figure 1D Depicted Figure 1B Edge view of a membrane cartridge.

[0027] Figure 1E Depicted Figure 1D Cross-sectional view of the membrane cartridge through AA.

[0028] Figure 2A An exploded view of a second embodiment of a membrane cartridge is depicted.

[0029] Figure 2B Depicted Figure 2A Perspective view of a membrane filter element.

[0030] Figure 3A An exploded view of a third embodiment of a membrane cartridge is depicted.

[0031] Figure 3B Depicted Figure 3A Perspective view of a membrane filter element.

[0032] Figure 4A An exploded view of a dehumidifier is depicted.

[0033] Figure 4B Depicted Figure 4A A first perspective view of a dehumidifier.

[0034] Figure 4C Depicted Figure 4B Bottom view of a dehumidifier.

[0035] Figure 4D Depicted Figure 4C A cross-sectional view of a dehumidifier through the BB.

[0036] Figure 4E Depicted Figure 4A A second perspective view of a dehumidifier.

[0037] Figure 4F Depicted Figure 4E A side cross-sectional view of a dehumidifier.

[0038] Figure 5A Describes a dehumidifier utilizing the present invention Figure 5A Exploded view of the dehumidifier system.

[0039] Figure 5B Depicted Figure 5A Schematic diagram of sensor placement in a dehumidifier system using a membrane cartridge module containing 3 membrane cartridges of the present invention, for a total of 6 membranes.

[0040] Fig. 6A Plots the integrated energy factor (IEF, L / kWh) versus different inlet conditions (relative humidity (RH, %) and temperature (T, °C)) and flow rate (CFM), which summarizes Figure 5B Performance results of the dehumidifier system.

[0041] Figure 6B Depicted showing Figure 5B A plot of relative humidity and temperature at different flow rates for a dehumidifier system in a high humidity environment.

[0042] Figure 6C Depicted showing Figure 5B A plot of relative humidity and temperature at different flow rates for a dehumidifier system in a low humidity environment.

[0043] Fig. 7A Plots of the comprehensive energy factor (L / kWh) and humidity ratio (GPP) versus inlet temperature (°C) at various temperatures between 20°C and 52°C summarize Figure 5A The dehumidification performance of a dehumidifier system at a flow rate of 250 CFM, the dehumidifier system comprising two membrane filter cartridge modules, each membrane filter cartridge module containing 15 membrane filter cartridges of the present invention, and each module having a total of 30 membranes.

[0044] Figure 7B Plotted at a constant temperature of 20°C the comprehensive energy factor (L / kWh) versus the inlet humidity ratio (GPP), which shows the generation of Fig. 7A The results in Figure 2 show the dehumidification performance of the same dehumidifier system at a flow rate of 250 CFM.

[0045] Figure 7C Plots of the comprehensive energy factor (L / kWh) and humidity ratio (GPP) versus inlet temperature (°C) at various temperatures between 20°C and 43°C summarize the generation of Fig. 7A The results in Figure 2 show the dehumidification performance of the same dehumidifier system at a flow rate of 250 CFM.

[0046] Fig.7D Plots the comprehensive energy factor (L / kWh) versus the inlet humidity ratio (GPP) versus the flow rate (CFM) at a constant temperature of 30°C, showing the generation of Fig. 7A The results show the dehumidification performance of the same dehumidifier system.

[0047] Fig. 7E Plots the pressure differential (D / F, Pa) versus total flow rate (CFM) to show the effect of Fig. 7A Results from a dehumidifier system show how the pressure difference across the membrane filter module increases as the flow rate increases. DETAILED DESCRIPTION

[0048] refer to Figures 1A to 1E, a first embodiment of a membrane cartridge 1 comprises a rectangular cartridge frame 3 having four edges 5 (only two are labeled) defining an interior cavity 7, the cartridge frame 3 having opposing face openings 9, 10 into the interior cavity 7. One of the edges 5 of the cartridge frame 3, specifically labeled 5a, comprises a plurality of edge openings 11 (only one is labeled) in fluid communication with the interior cavity 7 and the opposing face openings 9, 10. The edge openings 11 are formed through the cartridge frame 3 between the outer edge portion and the inner edge portion of the edge 5a so that fluid (e.g., water vapor or liquid) collected in the interior cavity 7 during use of the membrane cartridge 1 can be removed from the interior cavity 7. The membrane cartridge 1 comprises opposing perforated rectangular inserts 13, 15 in the form of rectangular plates having peripheral borders 14, 16 and a plurality of perforations, the insert 13 being aligned with the face opening 9 on one face of the cartridge frame 3, and the insert 15 being aligned with the face opening 10 on the opposing face of the cartridge frame 3.

[0049] The cartridge frame 3 includes a peripheral recess 17 in the inner edge portion of the rim 5, one of the recesses 17 surrounding the face opening 9 and another of the recesses (not shown) surrounding the face opening 10. The borders 14, 16 of the inserts 13, 15 engage with the respective recesses 17 in the rim 5 of the cartridge frame 3 adjacent to the respective face openings 9, 10. Thus, the inserts 13, 15 cover the face openings 9, 10, respectively, to define the interior cavity 7 between the rims 5 and between the inserts 13, 15. The recess 17 has a depth that allows the inserts 13, 15 to fit in the cartridge frame 3 so that the outer surfaces of the inserts 13, 15 are flush with the opposing surfaces of the cartridge frame 3. Each of the inserts 13, 15 includes a plurality of locking pins 19 extending into the interior cavity 7 and a plurality of struts 20 including receiving holes that also extend into the interior cavity 7. The locking pin 19 of the insert 13 is aligned with the pillar 20 of the insert 15, and the locking pin 19 of the insert 15 is aligned with the pillar 20 of the insert 13, so that the locking pin 19 can be inserted into the receiving hole of the pillar 20 to fix the two inserts 13, 15 together in a snap-fit ​​manner, thereby fixing the filter element frame 3 between the inserts 13, 15 without directly attaching the boundaries 14, 16 of the inserts 13, 15 to the filter element frame 3.

[0050] The membrane filter element 1 further comprises opposing rectangular graphene oxide semipermeable membranes 21, 23, which are supported on and cover the inserts 13, 15, respectively. The membranes 21, 23 are bonded by epoxy-cyanoacrylate adhesives 25, 27 (e.g., Loctite TMThe annular beads of the filter element 4090 are attached to the edge 5 of the filter element frame 3 and sealed therewith. The membrane filter element 1 further includes two locating holes 29 located in the same edge 5a as the edge opening 11, and when the membrane filter element 1 is installed in the dehumidifier, the locating holes 29 can be aligned with the corresponding one or more indexing pins on the dehumidifier to properly align the membrane filter element 1. The membrane filter element 1 further includes a plurality of fastener receivers 28 (only one is marked) located in the same edge 5a as the edge opening 11, for example, bolt holes, and the fastener receivers 28 are configured to engage with fasteners (e.g., bolts) to fix the membrane filter element 1 to the dehumidifier.

[0051] When used in a dehumidifier, when a humid gas flow (e.g., humid air) passes through the graphene oxide semipermeable membranes 21, 23, at least some of the water vapor in the gas flow passes through the membranes 21, 23 and then passes through the perforations in the inserts 13, 15 into the internal cavity 7, thereby dehumidifying the gas flow. The water vapor and condensed liquid water can be discharged through the edge openings 11 in the filter element frame 3 to prevent water from accumulating in the membrane filter element 1.

[0052] refer to Figure 2A and Figure 2B , a second embodiment of a membrane filter element 41 is similar to the membrane filter element 1, having a rectangular filter element frame 43, rectangular perforated inserts 53, 55 and graphene oxide semipermeable membranes 61, 63, whereby the membranes 61, 63 are supported on the inserts 53, 55, and the inserts 53, 55 are connected together in the same manner as in the membrane filter element 1. The membrane filter element 41 differs from the membrane filter element 1 in that the filter element frame 45 has no recess. Instead, the inserts 53, 55 float freely together within the inner edge portion of the edge 45 of the filter element frame 43, and the membranes 61, 63 are attached to the filter element frame 43 and sealed thereto by annular beads of adhesive 65, 67 to hold the inserts 53, 55 in place within the filter element frame 43. As shown by comparison Figure 2B and Figure 1B It can be seen that the fully assembled membrane filter element 41 is identical in appearance to the fully assembled membrane filter element 1 .

[0053] refer to Figure 3A and Figure 3B, a third embodiment of the membrane filter element 71 is similar to the membrane filter element 41, having a rectangular filter element frame 73, rectangular perforated inserts 83, 85 and graphene oxide semipermeable membranes 91, 93, whereby the membranes 91, 93 are supported on the inserts 83, 85. The membrane filter element 71 differs from the membrane filter element 41 in that the inserts 83, 85 are not connected together by pins and struts having receiving holes. Instead, the inserts 83, 85 are glued together. The inserts 83, 85 still float freely together within the inner edge portion of the edge 75 of the filter element frame 73, and the membranes 91, 93 are attached to the filter element frame 73 and sealed thereto by annular beads of adhesive 95, 97 to hold the inserts 83, 85 in place within the filter element frame 73. As shown by comparison Figure 3B and Figure 1B It can be seen that the fully assembled membrane filter element 71 is identical in appearance to the fully assembled membrane filter element 1 .

[0054] refer to 4A to 4F , depicts a dehumidification device 100 capable of utilizing membrane cartridges 1, 41, and 71. Device 100 includes a housing 101, housing 101 including a vacuum panel 103 at the bottom of housing 101, a pair of opposing side panels 105 attached to and extending upward from the vacuum panel 103, guide panels 121 connecting the side panels 105 at the top of housing 101, and a cover 107 connected to the top of the guide panels 121. Side panels 105 are attached to vacuum panel 103 by angle brackets 106. Housing 101 has opposing front and rear openings 109 and 111, respectively, to allow gas flow through housing 101.

[0055] The apparatus 100 further comprises a filter cartridge assembly 113 mounted on the vacuum plate 103, the filter cartridge assembly 113 comprising a plurality of spaced apart parallel membrane cartridges 114 (only one is labeled) arranged such that a plurality of parallel gas flow channels 115 exist between the faces of the membrane cartridges 114. The membrane cartridges 114 are aligned with the gas flow channels 115 such that the membrane cartridges 114 are parallel to the gas flow between the front opening 109 and the rear opening 111, and the gas flows through the housing 101 between the faces of the membrane cartridges 114 in the gas flow channels 115. The edges of the membrane cartridges 114 are adjacent to the housing 101, wherein the lower edge is adjacent to the vacuum plate 103, and the upper edge is adjacent to the cartridge spacer 117. The lower edge of the membrane cartridge 114 includes locating holes that can be aligned with and inserted over front and rear indexing pins 119 (only one is labeled) formed in the front and rear rows and spaced apart in between the rows to properly align and position the membrane cartridge 114 when the membrane cartridge 114 is installed in the housing 101. The cartridge spacer 117 includes a series of channels in which the upper edge of the membrane cartridge 114 is located to further help align, position and secure the membrane cartridge 114 in the housing 101. In addition, a single large hole is included in the guide plate 121, which is located at the top of the cartridge assembly 113 to help guide a single membrane cartridge 114 into place when it is installed in the housing 101.

[0056] The vacuum plate 103 includes a series of vacuum channels 127 aligned with the edge of the membrane cartridge 114. As described above in conjunction with the membrane cartridge 1, the vacuum channels 127 are in fluid communication with edge openings in the edge of the membrane cartridge 114, which are in fluid communication with corresponding internal cavities of the membrane cartridge 114. A first compressible airtight seal 129 (e.g., an elastomeric gasket) is located between the edge of the membrane cartridge 114 and the vacuum plate 103. A plurality of fasteners 131 (only one is labeled) (e.g., bolts) inserted through the vacuum channels 127 are aligned with fastener receivers (e.g., bolt holes) in the edge of the membrane cartridge 114, whereby engagement of the fasteners 131 with the fastener receivers is configured to pull the membrane cartridge 114 toward the vacuum plate 103, and thus toward the housing 100, to compress the seal. The apparatus 100 also includes a vacuum manifold 125, which is located below the vacuum plate 103 and is secured to the vacuum plate 103 by additional fasteners 133 (only one is labeled) (e.g., bolts). A second compressible airtight seal 135 (eg, an elastomeric gasket) is located between the vacuum manifold 125 and the vacuum plate 103. The vacuum manifold 125 includes a port 137 connectable to a vacuum system to apply a vacuum to the vacuum manifold 125, which is ultimately in fluid communication with the interior cavity of the membrane cartridge 114.

[0057] In operation, the wet gas (e.g., humid air) flowing through the dehumidification device 100 between the front opening 109 and the rear opening 111 flows through the gas flow channel 115 between the membrane filter element 114. Water vapor in the gas selectively passes through the selectively permeable membrane (e.g., graphene oxide membrane) into the interior cavity of the membrane filter element 114. With the help of the vacuum applied in the vacuum manifold 125, the water in the interior cavity of the membrane filter element 114 falls through the edge opening, and the vacuum manifold is ultimately in fluid communication with the interior cavity of the membrane filter element 114. Therefore, the gas leaving the device 100 is drier than the wet gas entering the device 100.

[0058] refer to Figure 5A and Figure 5B , a dehumidifier system 200 including a dehumidification device 150 of the present invention is shown. The dehumidification device 150 is shown as wide enough to accommodate three membrane cartridges (six membranes in total), but the dehumidification device 150 can be wider when more membrane cartridges are desired. The system 200 includes a housing 201 in which the dehumidification device 150 is mounted. An inlet adapter 203 is mounted above the front opening 159 of the dehumidification device 150 to allow fluid communication between the front opening 159 of the dehumidification device 150 and a blower fan 205, which draws wet air through an inlet duct 207 in which the fan 205 is mounted to deliver the wet air to the dehumidification device 150 through the inlet adapter 203. The inlet duct 207 is also mounted in the housing 201 and is in fluid communication with the external environment through an open front window 209 in the front wall of the housing 201, and the front window 209 is covered by an inlet filter 211, which filters particulate matter from the wet inlet airflow. An outlet duct 213 is mounted above the rear opening 161 of the dehumidification device 150 to allow fluid communication between the rear opening 161 of the dehumidification device 150 and the external environment through an open rear window 215 in the rear wall of the housing 201. The drier outlet airflow from the dehumidification device 150 is discharged through the open rear window 215, which is covered by an outlet filter 217, which prevents particulate matter from penetrating into the dehumidification device 150 through the outlet duct 213.

[0059] The bottom of the dehumidification device 150 is connected to the vacuum manifold 225 (see Figure 5B) is in fluid communication with a vacuum pump 221, which helps pump water vapor out of the dehumidification device 150 in the manner described above. The water vapor and pump heat are discharged through an exhaust outlet 223 connected to the vacuum pump 221. The exhaust outlet 223 can be connected to a drain. The housing 201 also includes an air port 224 located in the wall of the housing 201 to allow the air pressure in the housing 201 to equalize with the air pressure in the external environment. The air port 224 is covered by an air port filter 226 to help prevent particulate matter from entering the housing 201. The dehumidifier system 200 also includes an electrical cabinet 227, which contains electronic controls 228 for the dehumidifier system 200, including a programmable logic controller (PLC), and a display 229 on which system parameters can be displayed.

[0060] Figure 5B is a schematic diagram of a dehumidifier system 200 having a module 164 containing three membrane cartridges in a dehumidification device 150 and showing the placement of various sensors 230, including a humidity sensor 231, a temperature sensor 232, and a differential pressure sensor 233. The fan 205, vacuum pump 221, and electronic controls 228 all receive power through a power meter 235 for their respective operations.

[0061] Example 1

[0062] In one experiment, two dehumidifier systems 200 were built, each with three membrane cartridges and a rated air flow of 63 CFM. Each of the two systems had a PLC that could log data every 30 seconds and save up to one month of data. Each system was connected to the Internet so that the user could monitor the system in real time. After commissioning the system at the test site, an external humidifier was introduced to simulate higher humidity conditions to ensure that the system was working as expected because the ambient conditions were very dry. Both systems were run continuously indefinitely and in dehumidification mode to collect life data. FIG. 6A to FIG. 6C The results are shown.

[0063] Fig. 6A The results are summarized. As flow rates increase, the dehumidifier system can handle larger volumes of air and water vapor, which significantly improves the energy efficiency of the system. At higher relative humidity and inlet temperatures, the dehumidifier system performs best and can exceed the performance of conventional dehumidifiers.

[0064] Figure 6BA graph of artificially generated higher humidity is provided, where the relative humidity levels range from 70% to 90%, and the temperature ranges from 10°C to 20°C. Under these conditions, the dehumidification system was able to reduce the relative humidity by 15% to 25%, depending on the ambient humidity and temperature during the test. The system performed better under higher temperature and higher relative humidity conditions. However, at a flow rate of 280 CFM, the normalized relative humidity (RH) difference is higher, which may be an anomaly considering that the humidity ratio is much lower than the humidity ratio at higher temperatures.

[0065] The results are shown in Figure 6C Another set of tests in the involved real-world scenarios where the humidifier was turned off and the dehumidifier unit was exposed to a dry environment to evaluate the moisture removal capabilities of the system. At the time of the test, the relative humidity averaged 26%, which is considered fairly low. However, at an inlet temperature of 16°C, the dehumidifier system was still able to reduce the relative humidity by 5%. Another test was conducted by carefully evaluating the humidity removal performance at different flow rates. The flow rate was increased by two to four times the design flow rate of 63 CFM and a reduction in relative humidity removal was observed.

[0066] Example 2

[0067] In another experiment, the performance of two dehumidifier systems 200 was studied at various flow rates, temperatures, and humidity levels. The dehumidifier system included: filter modules, each with 30 membranes, rated at 125 CFM; a 375 cubic meter per hour vacuum pump system, which included a roots booster and a vacuum pump; and a vacuum pump PLC with variable frequency drive (VFD) controls for the roots booster. The experiment was conducted in a test room with the following: two air heaters; two humidifiers; a large blower fan box; two Accuvalve TM Air flow regulators; pressure, temperature and humidity sensors positioned before and after the filter module and in the vacuum line.

[0068] The test chamber allows the user to independently control the inlet conditions of each channel and filter module. However, for all tests performed, the inlet conditions of both channels were kept the same to ensure consistency between the two filter modules. Different inlet conditions of the filter modules may cause an imbalance in the vacuum level of each filter module, which may affect the overall power efficiency for a given set of inlet conditions.

[0069] All tests are performed in the following order:

[0070] Start the blower fan, turn on the heater, and increase the humidity.

[0071] Data was collected at different humidity levels at a fixed flow rate.

[0072] Increase temperature and vary humidity levels while maintaining flow.

[0073] Repeat the above steps until the desired temperature is reached, while recording the moisture removal and energy efficiency.

[0074] Specific temperatures and humidity levels were selected and flow rates were varied to evaluate moisture removal performance.

[0075] Captures important performance metrics of dehumidifier systems and summarizes them in Fig. 7A As the humidity ratio increases, the difference between the inlet and outlet (D / F) increases with the increase in IEF. This shows that the performance of the system is significantly improved at higher humidity ratios and higher humidity ratios can be achieved with higher inlet temperatures.

[0076] Figure 7B The graph in shows how the dehumidification performance increases with increasing humidity ratio at a constant temperature of 20°C. At an inlet humidity ratio of 53 GPP, the IEF is 0.3 L / kWh, and at an inlet humidity ratio of 98 GPP, the IEF is 0.7 L / kWh. This results in a 133% increase in IEF from the baseline to higher moisture contents.

[0077] like Figure 7B As shown, by increasing the humidity ratio at a fixed temperature, the IEF of the system can be increased. Figure 7C The graph in shows that dehumidification performance is improved by increasing temperature. At an inlet humidity ratio of 76 GPP, the IEF is 0.5 L / kWh, and at an inlet humidity ratio of 285 GPP, the IEF is 1.9 L / kWh. This causes an increase of 280% in IEF from 20°C to 43°C.

[0078] The dehumidifier system was designed to operate at a nominal flow rate of 250 CFM. However, the test chamber was able to push the flow rate up to 650 CFM. Fig.7D The graph in Figure 2 shows that as the flow rate increases, the D / F in the humidity ratio between the inlet and outlet decreases, but the IEF increases as the filter module processes more air. Between 250CFM and 650CFM, the humidity ratio D / F decreases from 56GPP to 32GPP, and the moisture removal rate decreases by 43%. Considering the same flow rate, the IEF increases from 0.91L / kWh to 1.29L / kWh, which is a 42% improvement over the rated flow rate.

[0079] Fig. 7EThe plots in show how the pressure differential across the filter modules increases with increasing flow rate. The experimental pressure D / F shows the measured pressure across each filter module, and the data is compared with calculated values ​​and computational fluid dynamics (CFD) predictions. The experimental pressure D / F is 18 Pa at a flow rate of 250 CFM, where the calculated value is 37% lower than the experimental data and the CFD model prediction is 8.4% lower than the experimental data. At the highest flow rate of 700 CFM, the experimental pressure D / F is 81 Pa, where the calculated value is 23% lower than the experimental data and the CFD model prediction is 30% higher than the experimental data. Due to the selected k-ε turbulence model, the CFD model tends to overestimate the pressure D / F, and this difference increases with increasing flow rate as the turbulent kinetic energy of the system increases. However, in most cases, the calculated pressure D / F is underestimated because the module geometry is not taken into account, which realizes an ideal case of flow in the air channel.

[0080] These novel features will become apparent to those skilled in the art upon examination of the description. However, it should be understood that the scope of the claims should not be limited by the embodiments, but should be given the broadest interpretation consistent with the wording of the claims and the entire specification.

Claims

1. A membrane filter element for a dehumidification device, the membrane filter element comprising: a cartridge frame having an interior cavity and having a first face opening and a second face opening in fluid communication with the interior cavity, the cartridge frame further having a rim including one or more rim openings in fluid communication with the interior cavity and the two face openings; a first insert comprising a first perforated surface aligned with the first face opening, the first perforated surface being defined by a first boundary adjacent the first face opening; a second insert comprising a second perforated surface aligned with the second face opening, the second perforated surface being defined by a second boundary adjacent the second face opening; a first membrane attached to the cartridge frame over the first insert and the first face opening, the first membrane sealed relative to the first face opening; as well as, A second membrane is attached to the cartridge frame over the second insert and the second face opening, the second membrane being sealed relative to the second face opening.

2. The filter element according to claim 1, wherein: The first insert includes a plurality of pins extending from the first perforated surface into the interior cavity; and the second insert includes a plurality of receiving holes into which the plurality of pins are inserted and secured.

3. A filter element according to claim 2, wherein the second perforated surface includes a plurality of pillars, the plurality of pillars extending from the second perforated surface into the internal cavity, the plurality of pillars including the plurality of receiving holes.

4. A filter element according to claim 3, wherein the second perforated surface includes an additional plurality of pins extending into the internal cavity, and the first perforated surface includes an additional plurality of pillars, the additional plurality of pillars include an additional plurality of receiving holes, and other plurality of pins are inserted into the additional plurality of receiving holes and fixed in the additional plurality of receiving holes.

5. The filter element according to any one of claims 1 to 4, wherein: The frame includes a first recess, the first recess is open around the first face, the first boundary is engaged with the first recess; and, The frame includes a second recess that is open around the second face, and the second boundary is engaged with the second recess.

6. The filter element of claim 5, wherein the frame is not attached to the first boundary and the second boundary.

7. The filter element according to any one of claims 1 to 6, wherein the first membrane and the second membrane are attached and sealed to the frame by an adhesive.

8. A filter element according to any one of claims 1 to 7, wherein the edge includes one or more positioning holes, and the one or more positioning holes can be aligned with corresponding one or more indexing pins on the dehumidifier to properly align the filter element when the filter element is installed in the dehumidifier.

9. The filter element of any one of claims 1 to 8, wherein the first membrane, the second membrane, or both the first membrane and the second membrane comprise graphene oxide.

10. A dehumidification device, comprising: a housing having an opening to allow gas flow therethrough; a membrane filter element, the membrane filter element being parallel to the gas flow, the membrane filter element having an edge adjacent to the housing; a compressible seal disposed between the edge of the membrane cartridge and the housing; as well as, A fastener is located between the housing and the membrane cartridge, the fastener being configured to pull the membrane cartridge toward the housing to compress the seal.

11. The apparatus of claim 10, further comprising a vacuum chamber in fluid communication with the edge of the membrane cartridge, the fastener being positioned within the vacuum chamber.

12. An apparatus according to claim 10 or claim 11, wherein the membrane filter element is one of a plurality of membrane filter elements and the housing includes a plurality of indexing pins to help place the membrane filter elements parallel to each other in a stack of filter elements in the apparatus.

13. The device according to any one of claims 10 to 12, wherein the membrane filter element is the membrane filter element according to any one of claims 1 to 10, and the edge of the membrane filter element is the edge of the filter element frame containing the one or more edge openings.

14. A dehumidifier system comprising the apparatus according to any one of claims 10 to 13.

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