Membrane capacitive deionization electrode assembly, housing structure, module, and method of treating a liquid

Abstract

The invention relates to a membrane capacitive deionization electrode assembly, a housing structure, a module and a method of treating a liquid. A membrane capacitive deionization electrode assembly comprising a flexible anion electrode, an anion exchange membrane, a cation exchange membrane, a flexible cation electrode, and a spacer, wherein the anion electrode comprises at least one anion electrode extension extending outward from an edge in the anion electrode, the cation electrode comprises at least one cation electrode extension extending outward from an edge in the cation electrode, the directions of the extensions are opposite to each other, the cation electrode extension comprises a cation electrode connection and / or the anion electrode extension comprises an anion electrode connection to facilitate power supply to the cation electrode and / or the anion electrode. The invention advantageously reduces the structural complexity of the module, ensures a lower contact resistance and a sealed structure.

Description

TECHNICAL FIELD

[0001] The present invention relates to capacitive deionization technology, and in particular to a membrane capacitive deionization electrode assembly, a housing structure for the electrode assembly, a module comprising the membrane capacitive deionization electrode assembly and the housing structure, and a method of treating a liquid to be treated using the membrane capacitive deionization electrode assembly. BACKGROUND

[0002] Water resource shortage is becoming a serious problem due to economic development, population growth, and climate change. Traditional seawater desalination technologies including electrodialysis (ED) and membrane distillation (MD) are not competitive with the main technology for seawater desalination, reverse osmosis (RO), due to high cost and energy consumption. However, fouling and high pressure limit the application of reverse osmosis, especially when treating high hardness water, because the need for frequent replacement of reverse osmosis membranes and the use of high pressure pumps increase capital and operating costs.

[0003] Capacitive deionization technology (CDI) is currently being developed as an energy-saving, renewable, and non-secondary pollution desalination technology. CDI uses porous carbon materials as electrodes, and when salt water flows between the electrodes, ions are adsorbed and fixed to the electrodes due to the action of the electric field, thereby reducing the salt water content.

[0004] Membrane capacitive deionization technology (MCDI) is an emerging desalination technology for seawater desalination and ion selective removal and recovery. Compared with traditional reverse osmosis membrane processes and electrodialysis, MCDI has the advantages of low energy consumption, low chemical consumption, and high water recovery rate. SUMMARY

[0005] The present invention proposes a new technology to set up and provide a membrane capacitive deionization electrode assembly and its housing structure, as well as related modules and methods, so as to better set up the electrode assembly structure to facilitate improved productivity and wastewater filtration.

[0006] The present invention proposes a membrane capacitive deionization electrode assembly, comprising,

[0007] a flexible anion electrode for attracting anions in a liquid to be treated in a channel;

[0008] a cation exchange membrane disposed adjacent to the anion electrode for passing cations and preventing anions from passing;

[0009] a cation exchange membrane spaced apart from the anion exchange membrane by a channel for passing cations and preventing anions from passing; and

[0010] a flexible cation electrode disposed adjacent to the cation exchange membrane for attracting cations in the liquid to be treated in the channel;

[0011] a spacer sheet in a flow path of the liquid between the anion exchange membrane and the cation exchange membrane for spacing the anion exchange membrane and the cation exchange membrane and directing the flow of the liquid;

[0012] wherein the anion electrode includes at least one anion electrode extension extending outwardly from an edge in the anion electrode, wherein the cation electrode includes at least one cation electrode extension extending outwardly from an edge of the cation electrode, the anion electrode extension and the cation electrode extension extending in opposite directions from each other.

[0013] wherein the cation electrode extension includes a cation electrode connector connected to or integral with the cation electrode extension and extendable angularly inwardly from the cation electrode extension, and / or the anion electrode extension includes an anion electrode connector connected to or integral with the anion electrode extension and extendable angularly inwardly from the anion electrode extension, to facilitate powering of the cation electrode and / or the anion electrode.

[0014] In an aspect, the cation electrode extension includes an opening therein for the cation electrode, and / or the anion electrode extension includes an opening therein for the anion electrode, to facilitate securing of the membrane capacitive deionization electrode assembly through the opening upon installation.

[0015] In an aspect, the cation electrode connector is formed by cutting the cation electrode extension into a tab shape, and the anion electrode connector is formed by cutting the anion electrode extension into a tab shape.

[0016] In an aspect, the cation electrode and the cation electrode extension are graphite sheets or metal sheets, and the anion electrode and the anion electrode extension are graphite sheets or metal sheets.

[0017] In an aspect, the cation electrode extension includes a rim aperture for the cation electrode, the rim aperture for the cation electrode being located adjacent to or in communication with the opening of the cation electrode extension; and / or the anion electrode extension includes a rim aperture for the anion electrode, the rim aperture for the anion electrode being located adjacent to or in communication with the opening of the anion electrode extension.

[0018] In one aspect, the membrane capacitive deionization electrode assembly includes a through hole to allow the treated liquid to flow out of the membrane capacitive deionization electrode assembly via the through hole.

[0019] The present application also provides a housing structure for an electrode assembly, the housing structure comprising

[0020] a top plate located at a top portion;

[0021] a bottom plate located at a bottom portion;

[0022] a peripheral housing located between the top plate and the bottom plate and connected to peripheral portions of the top plate and the bottom plate, the top plate, the bottom plate and the peripheral housing forming an internal space for the electrode assembly;

[0023] a positive electrode component and a negative electrode component, the positive electrode component and the negative electrode component being respectively located within the space enclosed by the peripheral housing, the positive electrode component and the negative electrode component being respectively coupled to a positive electrode and a negative electrode of a power source for electrically conductive coupling to electrodes of the electrode assembly when the electrode assembly is installed; and

[0024] at least two fixing structures made of non-conductive material, the fixing structures being respectively located within the space enclosed by the peripheral housing and spaced apart from the positive electrode component and the negative electrode component to facilitate installation of the electrode assembly;

[0025] wherein the fixing structure comprises an upper portion and a lower portion, a lower surface of the upper portion being inclined, an upper surface of the lower portion being inclined and corresponding to the inclination of the lower surface of the upper portion to facilitate outward movement of the upper portion relative to the lower portion along the upper surface of the lower portion.

[0026] In one aspect, the housing structure further comprises a plurality of fixing columns, the plurality of fixing columns being located within the internal space and between the positive electrode component and the negative electrode component to facilitate installation of the electrode assembly.

[0027] In one aspect, the upper portion of the fixing structure is fixed to the lower portion at a position offset from the lower portion after movement.

[0028] In one aspect, the upper portion of the fixing structure comprises a hole for fixing the upper portion to the lower portion through the hole.

[0029] In one aspect, the hole comprises two circular holes and a long strip-shaped hole located between the two circular holes.

[0030] In one aspect, the internal-facing surfaces of the positive electrode component and the negative electrode component are planar, and the surfaces of the fixing structure opposite to the positive electrode component and the negative electrode component are planar.

[0031] In an aspect, the housing structure further comprises a gasket between the top plate and the peripheral housing and / or between the bottom plate and the peripheral housing.

[0032] In an aspect, the housing structure further comprises a positive conductive device coupled to the positive component and a negative conductive device coupled to the negative component.

[0033] In an aspect, the housing structure is connected to a positive conductive device and a negative conductive device, the positive conductive device coupled to the positive component via one of the top plate, the bottom plate and the peripheral housing, the negative conductive device coupled to the negative component via one of the top plate, the bottom plate and the peripheral housing.

[0034] In an aspect, the positive conductive device and the negative conductive device are respectively coupled to the positive component and the negative component in a sealed manner to avoid contact with the liquid to be treated in the housing structure.

[0035] The present disclosure further provides a module comprising at least one membrane capacitive deionization electrode assembly as described above and a housing structure as described above, the membrane capacitive deionization electrode assembly disposed on the bottom plate, the anion electrode extension and / or the anion electrode connection contacting the positive component of the housing structure, the cation electrode extension and / or the cation electrode connection contacting the negative component of the housing structure.

[0036] In an aspect, the number of the membrane capacitive deionization electrode assemblies is two or more, the plurality of membrane capacitive deionization electrode assemblies stacked in sequence to form a set of membrane capacitive deionization electrode assemblies or multiple sets of membrane capacitive deionization electrode assemblies, wherein each membrane capacitive deionization electrode assembly is disposed in the housing structure in a sequence of positive and negative directions in an alternating manner.

[0037] In an aspect, further comprising a partition plate, the multiple sets of membrane capacitive deionization electrode assemblies disposed as a multi-layer structure, each layer separated by the partition plate.

[0038] In an aspect, further comprising a top support plate, the top support plate comprising at least one sealing portion on the main body of the top support plate, the sealing portion being a protrusion having a hollow portion, the at least one of the positive conductive device and the negative conductive device inserted into the hollow portion, and the protrusion embedded into a top opening of the at least one of the positive component and the negative component, such that the at least one of the positive conductive device and the negative conductive device is coupled to the at least one of the positive component and the negative component in a sealed manner.

[0039] In an aspect, the main body of the top support plate comprises a plurality of mounting recesses for the fixation post to be snapped into the mounting recesses to assist positioning when mounted.

[0040] The application also provides a method for treating liquid to be treated by using the membrane capacitive deionization electrode assembly or the module as described above, wherein after the membrane capacitive deionization electrode assembly is powered on, the liquid to be treated is allowed to flow through the membrane capacitive deionization electrode assembly, so that the particles containing anions and cations are adsorbed to the anion electrode and the cation electrode.

[0041] By using the MCDI electrode assembly and the shell structure, the module and the method, the structural complexity of the module is reduced, the problem of low production efficiency is solved, the lower contact resistance and the sealed structure are ensured, and the functions of water desalination and wastewater recovery are effectively realized. BRIEF DESCRIPTION OF DRAWINGS

[0042] The exemplary embodiments of the application will be described below with reference to the accompanying drawings. In the drawings, there are shown:

[0043] Figure 1 A schematic diagram of an electrode assembly for deionization according to an embodiment of the application is shown, which is a membrane capacitive deionization (MCDI) electrode assembly.

[0044] Figure 2 A schematic diagram of a module for the electrode assembly as described above according to an embodiment of the application is shown. Figure 1

[0045] Figure 3 A top view schematic diagram of a module including a MCDI electrode assembly according to an embodiment of the application is shown.

[0046] Figure 4 A schematic diagram of an example test cycle representing TDS variation during a cycle according to an embodiment of the application is shown.

[0047] Figure 5 A schematic diagram of a module including a MCDI electrode assembly according to an embodiment of the application is shown.

[0048] Figure 6 An enlarged structural diagram of a module according to another embodiment of the application is shown.

[0049] Figure 7 An exploded structural diagram of a module including multiple groups of MCDI electrode assemblies according to another embodiment of the application is shown.

[0050] Figure 8 An exploded structural diagram of an internal structure of a module including multiple groups of MCDI electrode assemblies according to another embodiment of the application is shown.

[0051] Figure 9 A schematic diagram of an assembled internal structure of a module including multiple groups of MCDI electrode assemblies according to another embodiment of the application is shown. ​

[0052] Figure 10 Assembled structure schematic of a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown, wherein only half of the module is represented to clearly show its interior.

[0053] Figure 11 Cross-sectional schematic of a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0054] Figure 12 Schematic of a monolithic electrode according to another embodiment of the present application is shown, wherein anion electrode extension, anion electrode connection, cation electrode extension, cation electrode connection are shown.

[0055] Figure 13 Schematic of a peripheral housing and positive and negative components, positive and negative conductive means in a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0056] Figure 14 Enlarged schematic of positive components and positive conductive means in a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0057] Figure 15 Front schematic of a separator in a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0058] Figure 16 Back schematic of a separator in a module comprising multiple sets of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0059] Figure 17 Schematic of internal structure in a module comprising only one set of MCDI electrode assemblies according to another embodiment of the present application is shown.

[0060] Figure 18 Schematic of a bottom support plate of a module comprising MCDI electrode assemblies according to another embodiment of the present application is shown.

[0061] Figure 19 Enlarged schematic of positive conductive means of a module comprising MCDI electrode assemblies according to another embodiment of the present application is shown.

[0062] BRIEF DESCRIPTION OF THE DRAWINGS

[0063] 1 - anion electrode, 101 - anion electrode extension, 102 - anion electrode connection, 103 - opening, 104 - edge aperture, 2 - anion exchange membrane, 3 - spacer sheet, 4 - cation exchange membrane, 5 - cation electrode, 501 - cation electrode extension, 502 - cation electrode connection, 503 - opening, 504 - edge aperture;

[0064] 9 - top plate, 10 - bottom plate, 11 - positive electrode conducting device, 12 - peripheral housing, 13 - gasket, 14 - positive electrode component, 15 - positive electrode side acrylic block, 16 - positive electrode side, 17 - fixing post, 18 - negative electrode side acrylic block, 19 - negative electrode side base block, 20 - negative electrode component, 21 - negative electrode conducting device, 22 - screw nut, 23 - screw nut, 24 - water outlet, 25 - water inlet;

[0065] 1301 - bottom surface, 1303 - positioning component, 1304 - positive electrode side base block, 1305 - negative electrode side base block, 1307 - protruding structure, 1309 - through hole, 1311 - recess, 601 - partition, 603 - flexible electrode sheet, 1001 - electrode side portion, 1003 - extended side portion, 1005 - opening portion, 1007 - open aperture portion, 1009 - through hole portion, 607 - positive electrode component, 608 - negative electrode component, 609 - mounting top plate, 611 - peripheral housing, 605 - acrylic block, 615 - bottom plate, 617 - top plate, 619 - top support plate, 621 - positive electrode side base block, 623 - connecting strip;

[0066] 1101 - positive electrode conducting device, 1103 - negative electrode conducting device, 1105 - first recessed portion, 1107 - second recessed portion, 1109 - gasket, 1111 - gasket, 1601 - main body, 1603 - mounting recess, 1605 - sealing portion, 1607 - through hole. DETAILED DESCRIPTION

[0067] The detailed description set forth below is designed to describe various configurations of the subject technology, and is not intended to represent the only configurations in which the subject technology can be practiced. The appended drawings are incorporated herein and constitute a part of the detailed description. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. However, it will be apparent to those skilled in the art that the subject technology is not limited to the specific details set forth and can be practiced using one or more embodiments. In one or more instances, structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject technology. One or more embodiments of the present disclosure are illustrated by and / or in connection with one or more figures.

[0068] One embodiment of the present invention relates to a MCDI electrode assembly. As Figure 1As shown, the MCDI electrode assembly includes a multilayer structure for depositing anions and cations of a medium flowing through it, such as a liquid medium. The MCDI electrode assembly includes an anion electrode 1, which can be formed by coating a graphite sheet with carbon paste. The carbon paste is formed by mixing activated carbon, carbon black, and polyvinylidene fluoride in a 1-methyl-2-pyrrolidone (NMP) solvent. The carbon coating formed by coating the graphite sheet with carbon paste, the graphite sheet itself, and the carbon coating can be rectangular, square, parallelogram, hexagonal, octagonal, circular, elliptical, etc., depending on the desired shape of the electrode assembly and module. In this embodiment, the graphite sheet and its carbon coating are rectangular, with lengths of 10-50cm, 15-45cm, 20-40cm, 25-35cm, etc., and widths of 5-40cm, 10-35cm, 15-30cm, 20-25cm, etc., for example, with an area of ​​23×19cm. 2 Of course, the length and width can also be set to be larger or smaller as needed.

[0069] like Figure 1 As shown, the graphite sheet in this embodiment also includes an anion electrode extension 101 extending along the long side of the graphite sheet serving as the anion electrode, and a cation electrode extension 501 extending from the other side of the cation electrode. The size of the extension can be slightly smaller than or smaller than the graphite sheet, for example, its length is 5-30cm, 9-25cm, 12-20cm, 15-18cm, etc., and its width is 2-20cm, 6-16cm, 10-15cm, 12-14cm, etc., for example, its area is 5×8cm. 2 Of course, the length and width can be set larger or smaller as needed. The interior of the sheet-like extension optionally has an opening 103, with a portion of its interior connected or integrally connected to a portion of the exterior of the extension at one end and separated at the other. The interior portion of the extension can be folded upwards or downwards to form the opening and the anion electrode connection portion 102. The opening 103 can be square to maximize the area of ​​the graphite sheet. The opening can be any suitable shape, such as circular, rectangular, or triangular. The inner tangent of the opening can be bent to curl at an angle to the electrode, forming a contact portion for power supply. Furthermore, the opening can also be used for connecting the power supply circuit, in addition to its fixing function. Of course, it may also be without an opening. Figure 1As shown, the anion electrode connecting part 102 is folded in the direction of the inside of the electrode assembly, so as to make the electrode stack. Alternatively, the anion electrode connecting part is formed by cutting the anion electrode extension part to form an opening for the anion electrode and a tab part for the anion electrode, which is a part of the anion electrode extension part. Preferably, in order to prevent the graphite sheet from being further torn by the inward cutting when the connecting part is formed, an edge opening 104 is formed on the graphite sheet, for example, a punch hole is cut, the diameter of which is adapted to the size of the anion electrode extension part 101 and the anion electrode connecting part 102, for example, a punch hole of 1-5 mm is formed on the extension part. The edge opening 104 can be located at the edge of the opening formed by cutting, the position communicating with the opening, the position between the two sides of the connecting part. For example, the edge opening 104 can be located at the opening on one side of the connecting part connected to the graphite sheet, at the openings on both sides of the connecting part connected to the graphite sheet, at the openings on both sides of the connecting part connected to the graphite sheet, at the middle position of the connecting part connected to the graphite sheet, etc. Preferably, the anion electrode further comprises a through hole 6 to allow the treated fluid or liquid, such as water, to flow out of the MCDI electrode assembly through the through hole. The through hole of the anion electrode can be located at the center of the electrode with a diameter of 0.5-5 cm, such as 1 cm, 2 cm, 3 cm, 4 cm, etc., or other positions, without limitation.

[0070] In the MCDI electrode assembly, a cation exchange membrane 2 is further included, which is arranged below and stacked with the anion electrode. The cation exchange membrane 2 is in the shape of a sheet, preferably the same shape as the anion electrode 1. In the adsorption stage, the cation exchange membrane allows anions to pass through and blocks cations from passing through, preventing the desorption of the adsorbed anions; in the regeneration stage, the desorbed ions cannot be re-adsorbed to the electrode due to the blocking of the cation exchange membrane. The cation exchange membrane 2 can be made of commercially available suitable materials, such as CJMA-4 and CJMC-4 of Hefei Chemjoy High Polymer Material Co., Ltd. In the present embodiment, the cation exchange membrane is rectangular, and its shape and size can be the same as the anion electrode, or can be set as needed, for example, its length is 10-50 cm, 15-45 cm, 20-40 cm, 25-35 cm, etc., its width is 5-40 cm, 10-35 cm, 15-30 cm, 20-25 cm, etc., for example, its area is 23x19 cm 2 . Preferably, the cation exchange membrane further comprises an opening to allow the treated medium, such as water, to flow out of the MCDI electrode assembly through the opening, which corresponds to the opening of the anion electrode, for example, can be located at the center of the electrode with a diameter of 0.5-5 cm, such as 1 cm, 2 cm, 3 cm, 4 cm, etc., without limitation.

[0071] The MCDI electrode assembly further includes a cation exchange membrane 4 and a cation electrode 5 corresponding to the anion electrode 1 and the anion exchange membrane 2. The cation electrode 5 can also be manufactured by coating a carbon paste on a graphite sheet, the carbon paste being as described above, and its shape and structure are preferably corresponding to the anion electrode 1, of course other shapes can also be selected, such as rectangular, square, parallelogram, hexagonal, octagonal, circular, elliptical, etc., depending on the shape of the electrode assembly and module required. The cation electrode 5 also includes a cation electrode extension 501 extending along the long side of the graphite sheet, which can be located on the side opposite to the position of the anion electrode extension 101 of the anion electrode 1. The size and dimension of the cation electrode extension 501 can correspond to or be different from the size and dimension of the anion electrode extension 101. The size of the cation electrode extension 501 can be slightly smaller or smaller than the graphite sheet as the cation electrode, for example, its length is 5-30 cm, 9-25 cm, 12-20 cm, 15-18 cm, etc., its width is 2-20 cm, 6-16 cm, 10-15 cm, 12-14 cm, etc., for example, its area is 5 x 8 cm 2 . Of course, the length and width can also be set larger or smaller as required. The sheet-shaped cation electrode extension 501 has an opening 503 in the inside, and the inside part of the cation electrode extension 501 is connected or integrally connected with the outside part of the cation electrode extension 501 at one end and separated at the other end, and the inside part of the cation electrode extension 501 can be folded upwards or downwards to form the opening and the cation electrode connecting part 502. The opening can be circular, rectangular or any suitable shape such as triangular, and the inscribed part of the opening can be curved to be crimped at an angle with the electrode to form a contact site for power supply. In addition, the opening can also be used for connection of the power supply circuit in addition to the fixing function. As Figure 1As shown, the cation electrode connecting part 502 is folded in the direction of the interior of the electrode assembly, so as to make the electrode stack. The cation electrode connecting part can also be extended from the cation electrode extension part without opening, as long as it can be clamped between the positive electrode part and the fixing part. Without opening, the cation electrode connecting part can be integrated with the cation electrode extension part, or joined together in a suitable manner. Alternatively, the cation electrode connecting part is formed by cutting the cation electrode extension part to form an opening for the cation electrode and a tab part for the cation electrode, which is a part of the cation electrode extension part. Preferably, in order to prevent further tearing of the graphite sheet when cutting inward to form the cation electrode connecting part, an edge opening 504 is formed on the graphite sheet, for example, cutting a punch hole with a diameter suitable for the size of the extension part and the connecting part, for example, forming a 1-5mm punch hole in the extension part. The edge opening 504 can be located at the edge of the opening formed by cutting, the position communicating with the opening, the position between the two sides of the connecting part. For example, the edge opening 504 can be located at the opening on one side of the edge of the cation electrode connecting part connected to the opening, at the openings on both sides of the edge of the cation electrode connecting part connected to the graphite sheet, at the middle position of the edge of the cation electrode connecting part connected to the graphite sheet, etc. Preferably, the anion electrode also includes a through hole to allow the treated medium, such as water, to flow out of the MCDI electrode assembly via the through hole. The through hole of the anion electrode can be located at the center of the electrode or any other suitable position, with a diameter of 0.5-5cm, for example, 1cm, 2cm, 3cm, 4cm, etc., without limitation. The cation electrode connecting part, the cation electrode extension part, and the anion electrode connecting part, the anion electrode extension part can be made of graphite sheet, or carbon cloth, which has conductivity and is not easily corroded in salt water, or other conductive materials

[0072] In the MCDI electrode assembly, a cation exchange membrane 4 is also included on top of the cation electrode and is stacked with the cation electrode 5. The cation exchange membrane 4 is similar to the anion exchange membrane 2. The cation exchange membrane is sheet-shaped, preferably, has the same shape as the cation electrode 5. The cation exchange membrane allows cations to pass through and blocks anions from passing through in the adsorption stage, preventing the cations that have been adsorbed from desorbing; in the regeneration stage, the desorbed ions cannot be re-adsorbed to the electrode due to the blocking of the cation exchange membrane. The liquid to be treated is present between the cation exchange membrane and the anion exchange membrane. The cation exchange membrane 4 can be made of the same material as the anion exchange membrane, made of commercially available suitable materials, such as CJMA-4 and CJMC-4 of Hefei Chemjoy Polymer Material Co., Ltd. In the present embodiment, the cation exchange membrane is rectangular, and its shape and size can be the same as the cation electrode, or can be set as needed, for example, its length is 10-50 cm, 15-45 cm, 20-40 cm, 25-35 cm, etc., its width is 5-40 cm, 10-35 cm, 15-30 cm, 20-25 cm, etc., for example, its area is 23 x 19 cm 2 . Preferably, the cation exchange membrane also includes an opening to allow the treated medium, such as water, to flow out of the MCDI electrode assembly via the opening, which corresponds to the opening of the cation electrode, for example, can be located at the center of the electrode, with a diameter of 0.5-5 cm, for example, 1 cm, 2 cm, 3 cm, 4 cm, etc., not limited thereto.

[0073] The MCDI electrode assembly also optionally includes a spacer 3 between the cation exchange membrane and the anion exchange membrane, which provides a flow path for the liquid to be treated, such as water, between the cation exchange membrane and the anion exchange membrane, and is a grid structure to facilitate the flow of water between the cation exchange membrane and the anion exchange membrane. The spacer 3 can be made of nylon, for example, or other suitable materials, and its size can be greater than, equal to, or less than the cation exchange membrane / anion exchange membrane. For example, the spacer is rectangular, for example, its length is 10-50 cm, 15-45 cm, 20-40 cm, 25-35 cm, etc., its width is 5-40 cm, 10-35 cm, 15-30 cm, 20-25 cm, etc., for example, its area is 23 x 19 cm 2 . Preferably, the spacer 3 also includes an opening to allow the treated medium, such as water, to flow out of the MCDI electrode assembly via the opening, which corresponds to the opening of the cation exchange membrane / anion exchange membrane, for example, can be located at the center of the electrode, with a diameter of 0.5-5 cm, for example, 1 cm, 2 cm, 3 cm, 4 cm, etc., not limited thereto.

[0074] During operation, a liquid or fluid, such as water, enters the MCDI electrode assembly from the outer edge of the spacer 3, flows through the spacer 3 between the cation exchange membrane and the anion exchange membrane, and exits through the channel formed by the aperture 6 of the anion electrode 1, the aperture of the anion exchange membrane 2, the optional aperture of the spacer 3, the optional channel formed by the aperture of the spacer 3, the aperture of the cation exchange membrane 4, and the aperture in the cation electrode 5.

[0075] Figure 2 A housing structure for an electrode assembly according to an embodiment of the present application is shown. The module comprises the following parts in a state where the electrode assembly is not installed. The housing structure comprises a housing including a top plate 9, a bottom plate 10 opposite to the top plate and spaced apart from the top plate by a distance, and a peripheral housing 12 connecting the top plate and the bottom plate by being located at the outer side of the top plate and the bottom plate, which can be detachably connected to facilitate replacement, or can be sealingly connected, such as by bolt sealing, by snap fitting sealing, by hinging sealing, etc. For example Figure 2 As shown, the top plate and the bottom plate are connected together by screws for sealing, and the number of the screws is, for example, 10. Preferably, a gasket, such as a non-conductive gasket, such as a silicone gasket, is provided at the joint of the peripheral housing and the top plate and the bottom plate, respectively, for waterproof sealing between the peripheral housing and the top plate and between the peripheral housing and the bottom plate.

[0076] The housing of the housing structure includes a positive electrode part 14 and a negative electrode part 20. The positive electrode part is located at the inner side of the peripheral housing, and the negative electrode part is located at the other inner side of the peripheral housing opposite to the positive electrode part. The positive electrode part and the negative electrode part are coupled to external positive electrode conductive devices 11 and negative electrode conductive devices 21 through two apertures of the peripheral housing, respectively. As shown Figure 2As shown, the positive component 14, for example in the form of a graphite block, is coupled to the positive conductive device 11, for example in the form of a positive copper rod, and the negative component 20, for example in the form of a graphite block, is coupled to the negative conductive device 21, for example in the form of a negative copper rod. The opening of the peripheral housing can correspond in size to the positive conductive device 11 and the negative conductive device 21 respectively, so that the positive copper rod and the negative copper rod can be accommodated therein, for example with a diameter of 1-10mm, 2-9mm, 3-8mm, 4-7mm, 5-6mm, etc. The positive conductive device 11 passes through the peripheral housing and is connected to the positive component 14, for example a graphite block, and optionally the positive conductive device 11 and the positive component 14 are screwed together by a screw nut 22 to strengthen the contact between the positive conductive device 11 and the positive component 14. The negative conductive device 21 passes through the peripheral housing and is connected to the negative component 20, for example a graphite block, and optionally the negative conductive device 21 and the negative component 20 are screwed together by a screw nut 23 to strengthen the contact between the negative conductive device 21 and the negative component 20. The positive component, the negative component, the positive conductive device and the negative conductive device are only used to distinguish one of the cation electrode and the anion electrode of the MCDI electrode assembly, which can be indirectly coupled according to the situation. In the case of multiple MCDI electrode assemblies, the multiple MCDI electrode assemblies are arranged in sequence in reverse order. For example, the positive component connects the upper anion electrode of the odd-numbered MCDI electrode assembly and the lower anion electrode of the even-numbered MCDI electrode assembly; the negative component connects the lower cation electrode of the odd-numbered MCDI electrode assembly and the upper cation electrode of the even-numbered MCDI electrode assembly, and so on. For example, the positive component connects the upper anion electrode of the first MCDI electrode assembly, the lower anion electrode of the second MCDI electrode assembly, and the upper anion electrode of the third MCDI electrode assembly; the negative component connects the lower cation electrode of the first MCDI electrode assembly, the upper cation electrode of the second MCDI electrode assembly, and the lower cation electrode of the third MCDI electrode assembly, and so on. Or in any other suitable way.

[0077] Optionally, a gasket 13 is arranged between the positive conductive device 14 and the peripheral housing 12 and between the negative conductive device 21 and the peripheral housing 12 respectively, to prevent liquid from contacting the positive conductive device 11 and the negative conductive device 21. The gasket 13 can be an insulating gasket, preferably an elastic gasket, for example a silicone gasket, or any other suitable gasket. In this embodiment, two silicone gaskets are used. The gasket 13 can completely cover and surround the positive conductive device 11 and the negative conductive device 21, and be used to fix the total height of the stacked electrode pieces. In addition, the gasket can also be used to seal the positive conductive device 11 and the negative conductive device 21 from liquid.

[0078] The outer casing structure also includes at least two fixing structures located within the outer casing 12, the fixing structures being made of a non-conductive material. As shown, the fixing structures are located within the space enclosed by the outer casing and spaced apart from the positive and negative electrode components to facilitate the installation of the electrode assembly. Each fixing structure includes an upper part and a lower part, the upper part being movable relative to the lower part. The lower surface of the upper part is inclined, and the upper surface of the lower part is inclined and corresponds to the inclination of the lower surface of the upper part, so that the upper part can move outward along the upper surface of the lower part.

[0079] like Figure 5 As shown in the figure, the positive electrode side acrylic block 15, representing the upper part of the fixing structure corresponding to the positive electrode component, and the negative electrode side acrylic block 18, representing the upper part of another fixing structure corresponding to the negative electrode component, are respectively shown in the figure. The positive electrode side acrylic block 15 and the negative electrode side acrylic block 18 are located inside the positive electrode component 14 and the negative electrode component 20, respectively. The positive electrode side base block 16, which serves as the lower part of the fixing structure to support the positive electrode side acrylic block 15, and the negative electrode side base block 19, which serves as the lower part of the fixing structure to support the negative electrode side acrylic block 18, are respectively located inside the positive electrode component 14 and the negative electrode side acrylic block 18. Figure 5 The Chinese character indicates this. For example... Figure 6 As shown, the upper surface of the positive electrode side base block 16 is inclined, and the lower surface of the positive electrode side acrylic block 15 has a corresponding slope. The positive electrode side acrylic block 15 and the negative electrode side acrylic block 18 have an angle extending upward at an angle of 5° to 30° in the direction toward the inside of the housing, so as to match the slope of the upper surfaces of the positive electrode side base block 16 and the negative electrode side base block 19 on the base plate 1.

[0080] On installation, the opening in the cation electrode extension is first mounted to the positive side acrylic block 15, the cation electrode connector is then placed in the gap between the positive component 14 and the positive side acrylic block 15, the positive side acrylic block 15 is then moved along the positive side base block towards the outside along the upper surface of the positive side base block, sliding down to press the cation electrode connector firmly against the positive component 14. Similar operations are performed on the negative side acrylic block 18. After installation, the anion electrode connector 102 / cation electrode connector 502 is sandwiched between the positive side acrylic block 15 / negative side acrylic block 18 and the positive component 14 / negative component 20, the anion electrode connector 102 / cation electrode connector 502 is pressed to the positive component 14 / negative component 20 by the positive side acrylic block 15 / negative side acrylic block 18 to achieve the strengthened electrical contact between the anion electrode connector 102 / cation electrode connector 502 and the positive component 14 / negative component 20. After connection, the anion electrode connector 102 and the cation electrode connector 502 will not displace or vibrate at all even at the maximum flow rate of the fluid. Thus, not only can the anion electrode connector / cation electrode connector be fixed, but also the contact is conductive by pressing the anion electrode connector / cation electrode connector, for example, carbon paper, to the positive component / negative component, for example, graphite block. Thus, the requirement for extremely low contact resistance is achieved, the resistance can be guaranteed to be below 0.02 ohm, thus the assembly can be effectively operated.

[0081] The positive side acrylic block 15 and the negative side acrylic block 18 are mounted to the base plate 10. The acrylic blocks can be mounted in a removable manner using screws, snaps, adhesives, etc. or can be mounted using welding, hinging, etc. Optionally, the upper portion of the positive side acrylic block 15 and the negative side acrylic block 18 include holes for securing the positive side acrylic block 15 and the negative side acrylic block 18 to the positive side base block 16 and the negative side base block 19 via the holes. For example, the holes can be holes in the middle of the upper surface of the positive side acrylic block 15 and the negative side acrylic block 18 or other suitable locations that allow for a screw to pass through the hole and be tightened to the base plate. The holes can be any suitable shape, such as circular, oval, etc. For example, the holes can be in the form of a keyhole, with a circular hole on either side and a long, strip-shaped hole between the two circular holes that is in communication with the circular holes. For example, the holes can be in the form of a one-sided partially open hole to facilitate mounting and securing of the positive side acrylic block 15 and the negative side acrylic block 18 after movement. The positive side base block 16 and the negative side base block 19 are positioned below the positive side acrylic block 15 and the negative side acrylic block 18 to support the positive side acrylic block 15 and the negative side acrylic block 18. The positive side base block 16 and the negative side base block 19 are secured to the base plate, such as by one or more screws or by an adhesive point, a welding point, a hinging device, a snapping device, etc. In the present embodiment, the positive side base block 16 and the negative side base block 19 are adhered to the base plate 10 to provide support for the positive side acrylic block 15 and the negative side acrylic block 18, respectively.

[0082] The surfaces of the positive and negative components that face the interior of the housing structure are planar, as are the surfaces of the positive side acrylic block 15 / negative side acrylic block 18 that are opposite the positive / negative components. Thus, after the cation electrode connection is positioned between the positive component 14 and the positive side acrylic block 15, the positive side acrylic block is slid until it is tightly against the positive component 14, resulting in a large area of contact between the cation electrode connection, the positive side acrylic block, and the positive component 14, reducing the contact resistance and maximizing the current. Similarly, after the anion electrode connection is positioned between the negative component 20 and the negative side acrylic block 18, the negative side acrylic block is slid until it is tightly against the negative component 20, resulting in a large area of contact between the anion electrode connection, the negative side acrylic block, and the negative component 20, reducing the contact resistance and maximizing the current.

[0083] The distance of the positive component 14 and the negative component 20 from the positive side acrylic block 15 and the negative side acrylic block 18 can also be adjusted by adjusting the thickness of the gasket 13.

[0084] Figure 3A top view schematic of a module comprising a MCDI electrode assembly is shown, according to an embodiment of the application, wherein the MCDI electrode assembly is placed in the middle of the module. As Figure 3As shown, the MCDI electrode assembly is fixedly mounted to the base plate 10, in this embodiment, the MCDI electrode assembly is fixed by 8 fixing posts 17 on the base plate 10 and the multiple MCDI electrode assemblies are aligned when the number of MCDI electrode assemblies is multiple. The fixing posts 17 define the position of the MCDI electrode assembly by limiting the outer edge of the MCDI electrode assembly when the electrode assembly is mounted, and the fixing posts 17 can also cooperate with other structural parts of the housing structure to fix the position of other housing structures when the MCDI electrode assemblies are stacked. Of course, instead of the fixing posts, other suitable fixing structures can also be used. In order to assemble a complete module, each MCDI unit will be placed one by one in sequence. For example, the first MCDI electrode assembly is placed in the order of cation electrode 5, cation exchange membrane 4, spacer 3, anion exchange membrane 2 and anion electrode 1 from bottom to top. The cation electrode extension 501 and the anion electrode extension 101 pass through the negative electrode side base block 19 and the positive electrode side base block 16 respectively. The second MCDI electrode assembly is placed in the order of anion electrode 1, anion exchange membrane 2, spacer 3, cation exchange membrane 4 and cation electrode 5 from bottom to top, which is opposite to the order of the first MCDI electrode assembly. In this way, direct contact between the anion electrode and the cation electrode can be prevented, and short circuit can be avoided. The number of MCDI electrode assemblies arranged can be 1-20 pairs, for example, 3-15 pairs, 5-10 pairs, etc., which is not limited to the above. During the installation process, multiple pairs of MCDI electrode assemblies are placed first, and then the inwardly turned anion electrode connecting portion 102 and the cation electrode connecting portion 502 are turned, and then the peripheral housing with the positive electrode part 14 and the negative electrode part 20 and the positive electrode conducting device 11 and the negative electrode conducting device 21 is installed, and the peripheral housing is, for example, circular to provide electrical contacts. Then, more MCDI electrode assemblies can be further stacked at the bottom, and the number can be, for example, 3 to 15 pairs. When stacking, the turned anion electrode connecting portion 102 and the cation electrode connecting portion 502 are in contact with the positive electrode part 14 and the negative electrode part 20. In the case where the MCDI electrode assembly is installed, the connection between the anion electrode and the cation electrode of the electrode assembly is realized by electrical contact between the anion electrode connecting portion 102 and the positive electrode part 14 respectively. The positive electrode part 14 coupled with the positive electrode conducting device 11 is in contact with the anion electrode connecting portion 102 located at the anion electrode of the electrode assembly to realize the conduction of the anion electrode 1, and the negative electrode part 20 coupled with the negative electrode conducting device 21 is in contact with the cation electrode connecting portion 502 located at the cation electrode of the electrode assembly to realize the conduction of the cation electrode 5. After placing all the MCDI electrode assemblies, the anion electrode connecting portion 102 and the cation electrode connecting portion 502 are pressed onto the positive electrode part 14 and the negative electrode part 20 respectively by the positive electrode side acrylic block 15 and the negative electrode side acrylic block 18.In this embodiment, two screws can be used to secure the position of the acrylic blocks 15, 18. Then, the top plate 9 is placed on top of the module and the module is sealed with 10 bolts as shown in this embodiment. Of course, any other suitable means of sealing the module can be used, such as snap engagement, welding, hinging, gluing, etc. The medium, such as water, enters the MCDI electrode assembly through two water inlets 25 and flows radially through the spacers 3 and then exits the module through the water outlet 24. In addition, the design of the module is suitable for stacking of multiple MCDI's.

[0085] In operation of the MCDI module including the MCDI electrode assembly, water is pumped from a reservoir into the MCDI module by two peristaltic pumps. The water treated by the MCDI module can be analyzed by a conductivity probe. The output of the conductivity probe is converted to total dissolved solids based on a NaCl calibration. In this embodiment, the electrode assembly is powered by a DC power supply. Of course, any other suitable means of powering can be used. The positive component 14 and the negative component 20 are connected to the positive and negative conductive means 11, 21, respectively, which can be connected directly or through a conductive structure such as a cable. As shown, the electrode voltage and conductivity are recorded as a function of time. Figure 4

[0086] Another embodiment of the present invention relates to a stacked structure of MCDI electrode assemblies and a related structure of a housing. As shown, Figure 7 each MCDI electrode assembly is similar to the electrode assembly shown in Figure 1 and includes a flexible anion electrode for attracting anions in a liquid to be treated in a channel, an anion exchange membrane disposed adjacent to the anion electrode for passing anions and blocking cations, a cation exchange membrane spaced apart from the anion exchange membrane by the channel for passing cations and blocking anions, and a flexible cation electrode disposed adjacent to the cation exchange membrane for attracting cations in the liquid to be treated in the channel, and a spacer located in a flow path of a liquid, such as water, formed between the anion exchange membrane and the cation exchange membrane for spacing the anion exchange membrane and the cation exchange membrane and directing the flow of the liquid through the anion exchange membrane and the cation exchange membrane. In this stacked structure, multiple sets of electrode sheets are used, each set of electrodes is connected in parallel through respective cation electrode extensions and anion electrode extensions. The extensions function as conductive means.

[0087] ​The cation electrode extension includes a flexible cation electrode connecting portion, and the anion electrode extension includes a flexible anion electrode connecting portion. The cation electrode connecting portion is connected to or integrated with the cation electrode extension and extends from the cation electrode extension at an angle towards the interior of the electrode assembly. The anion electrode connecting portion is connected to or integrated with the anion electrode extension and extends from the anion electrode extension at an angle towards the interior of the electrode assembly, to facilitate the supply of power to the cation electrode and / or the anion electrode. The cation electrode connecting portion and the anion electrode connecting portion in the present embodiment also each include an opening portion in communication with the outside, for the provision of an upper portion of a fixing structure.

[0088] The materials, shapes, sizes, etc. of the anion electrode, the cation electrode, the cation exchange membrane, the anion exchange membrane in the MCDI electrode assembly can be the same, similar or different from those in the previous embodiments.

[0089] As shown in Figure 7 , the stacking structure of the MCDI electrode assembly includes multiple layers of MCDI electrode assemblies spaced apart, and a 5-layer structure is shown in the figure. Each layer is separated by a spacer 601. The spacer 601 is as shown in Figure 15 and 16 . The spacer 601 includes a bottom surface 1301, which is larger in size than the MCDI electrode assembly, to carry the MCDI electrode assembly. A plurality of positioning components 1303 are provided on the spacer, which are used to fix the position of the MCDI electrode assembly by abutting against the outer edge of the MCDI electrode assembly, to help install the electrode assembly. A positive electrode side base block 1304 and a negative electrode side base block 1305 are provided on the spacer located at the lowermost side, to support the upper portion of the fixing structure thereabove, such as the positive electrode side acrylic block and the negative electrode side acrylic block. The spacer can also optionally include a plurality of protruding structures 1307, to space apart the cation electrode extension and the anion electrode extension of each layer respectively after installation. The middle portion of the spacer includes a through hole 1309, to help the medium flow out. The back of the spacer includes a recess 1311, which corresponds to the position of the fixing column, to be clamped to position the spacer by the contact of the fixing column and the recess when a plurality of spacers are installed.

[0090] As shown in Figure 17 , when stacked, the MCDI electrode assemblies are arranged in turn with the positions of the cation electrode of the first MCDI electrode assembly corresponding to the positions of the anion electrode of the second MCDI electrode assembly, and the positions of the cation electrode of the second MCDI electrode assembly corresponding to the positions of the anion electrode of the third MCDI electrode assembly, so that the MCDI electrode assemblies are arranged in a stacked manner. The flexible electrode sheet 603 on the MCDI electrode assembly at the uppermost of each layer serves as the uppermost electrode of the top, and the spacer 601 serves as a spacing structure. The structure of the flexible electrode sheet 603 is as shown in Figure 12As shown, the MCDI electrode assembly includes an electrode side portion 1001, an extended side portion 1003, an opening portion 1005, an open opening portion 1007, and a through hole portion 1009. The electrode side portion 1001 is a rectangular structure, the extended side portion 1003 is located on one side of the electrode side portion, the opening portion 1005 is located in the extended side portion 1003, and the opening portion is used to pass the acrylic block and the base block in the fixing structure. The open opening portion 1007 is located on the opposite side of the electrode side portion in the extended side portion, and does not communicate with the opening portion, so as to facilitate the positive and negative components to pass through the open opening portion. The through hole portion 1009 is located in the middle of the electrode or other suitable parts, for allowing fluid to flow in or out.

[0091] As shown in FIGS. 1 and 2, the MCDI electrode assembly includes an electrode side portion 1001, an extended side portion 1003, an opening portion 1005, an open opening portion 1007, and a through hole portion 1009. The electrode side portion 1001 is a rectangular structure, the extended side portion 1003 is located on one side of the electrode side portion, the opening portion 1005 is located in the extended side portion 1003, and the opening portion is used to pass the acrylic block and the base block in the fixing structure. The open opening portion 1007 is located on the opposite side of the electrode side portion in the extended side portion, and does not communicate with the opening portion, so as to facilitate the positive and negative components to pass through the open opening portion. The through hole portion 1009 is located in the middle of the electrode or other suitable parts, for allowing fluid to flow in or out. Figure 8 Figure 9 As shown, when stacked, a plurality of MCDI electrode assemblies are arranged on the separator in sequence, and each of the plurality of MCDI electrode assemblies is arranged in sequence by turning over. Each MCDI electrode assembly is arranged as a layer, and in this embodiment, 5 layers of MCDI electrode assemblies can be stacked.

[0092] The outer shell of the MCDI electrode assembly includes at least two fixing structures located in the peripheral shell 607, and the fixing structures are made of non-conductive materials. As shown in FIGS. 1 and 2, the fixing structures are located in the space surrounded by the peripheral shell 607 and are spaced apart from the positive component 607 and the negative component 608 to help install the electrode assembly. The positive and negative components can be interchanged, and only their positions are indicated, not only their use for positive or negative. The fixing structure includes an acrylic block 605 as an upper part and a positive side base block 621 as a lower part (as shown in FIG. 3), one of the acrylic blocks can move relative to the positive side base block 621, the acrylic block is in the shape of a rectangular cuboid, the lower surface of which is inclined, and the upper surface of the positive side base block is inclined and corresponds to the slope of the lower surface of the acrylic block, so as to facilitate the acrylic block to move outward along the upper surface of the positive side base block. The fixing structure can be made of any suitable material with good mechanical properties and not easy to corrode in media such as salt water. The acrylic block 605 can be arranged to pass through the openings of the cation electrode extension and the anion electrode extension of the multilayer MCDI electrode to help fix the multilayer electrode, and the acrylic block 605 also abuts against the outer edge of the separator to help fix the position of the separator. Figure 6 Figure 7 As shown, the MCDI electrode assembly includes an electrode side portion 1001, an extended side portion 1003, an opening portion 1005, an open opening portion 1007, and a through hole portion 1009. The electrode side portion 1001 is a rectangular structure, the extended side portion 1003 is located on one side of the electrode side portion, the opening portion 1005 is located in the extended side portion 1003, and the opening portion is used to pass the acrylic block and the base block in the fixing structure. The open opening portion 1007 is located on the opposite side of the electrode side portion in the extended side portion, and does not communicate with the opening portion, so as to facilitate the positive and negative components to pass through the open opening portion. The through hole portion 1009 is located in the middle of the electrode or other suitable parts, for allowing fluid to flow in or out. Figure 8 The two acrylic blocks 605 of the fixing structure are connected by a connecting strip 623, the connecting strip is connected to the top surface of the positive side base block of the fixing structure, and the positive side base block of the fixing structure is connected by providing a hole on the top surface and locking with the hole of the connecting strip.

[0093] The two acrylic blocks 605 of the fixing structure are connected by a connecting strip 623, the connecting strip is connected to the top surface of the positive side base block of the fixing structure, and the positive side base block of the fixing structure is connected by providing a hole on the top surface and locking with the hole of the connecting strip.

[0094] ​​The acrylic blocks 605 of the fixing structure are respectively located on the inner side of the positive electrode part 607 and the negative electrode part 608 for tightly and large-area contacting the cation electrode extension and the anion electrode extension and / or the cation electrode connection and the anion electrode connection with the positive electrode part 607 and / or the negative electrode part 608. Among them, the cation electrode extension and the anion electrode extension and / or the cation electrode connection and the anion electrode connection of the electrode assembly in each layer of the MCDI electrode assembly extend downward to be clamped between the two acrylic blocks 605 of the fixing structure and the positive electrode part 607 and the negative electrode part 608. The clamped cation electrode extension and the anion electrode extension and / or the cation electrode connection and the anion electrode connection can be slightly overlapped in turn. In Figure 6 In the embodiment, the cation electrode connection and the anion electrode connection are pressed on the surface of the positive electrode part 607 and the negative electrode part 608 as the inner side along the surface of the acrylic block 605 of the fixing structure as the outer side with the cation electrode extension and the anion electrode extension at an angle or preferably almost perpendicular to the MCDI electrode assembly. In order to maximize the contact, the surface of the acrylic block 605 of the fixing structure as the outer side and the surface of the positive electrode part 607 and the negative electrode part 608 as the inner side are preferably both flat, and the maximum contact surface can be achieved during installation, for example, the surface of the acrylic block 605 of the fixing structure as the outer side and the surface of the positive electrode part 607 and the negative electrode part 608 as the inner side are almost completely in contact. The shape of the other surfaces of the acrylic block 605 of the fixing structure and the other surfaces of the positive electrode part 607 and the negative electrode part 608 can be other suitable shapes, not limited to flat. The lower surface of the fixing structure is inclined, and the upper surface of the lower part has a corresponding slope. The acrylic block has an angle extending upward at an angle of 5° to 30° along the direction towards the inside of the shell to match the slope of the upper surface of the lower part.

[0095] The installed module including multiple groups of MCDI electrode assemblies is as shown in Figure 10 and 11As shown, the top plate 617 and bottom plate 615 are joined to the outer housing to encapsulate the module including the MCDI electrode assembly. The cation electrode connection and anion electrode connection are respectively sandwiched between the fixing structures on both sides (particularly the upper part of the fixing structures, i.e., the acrylic block) and the positive electrode component 607 and the negative electrode component 608. The acrylic block slides outward along its inclined lower surface on the upper surface of the base block until it abuts against the positive electrode component 607 and the negative electrode component 608, ensuring that the cation electrode connection and anion electrode connection make tight, large-area contact with the positive electrode component 607 and the negative electrode component 608, reducing contact resistance. The positive electrode conductive device 11 and the negative electrode conductive device 21 are respectively inserted into the positive electrode component 607 and the negative electrode component 608 to supply power to them. The MCDI electrodes are closely arranged to maximize ion removal by placing as many MCDI electrodes as possible within a limited space. The cation electrode extension and the anion electrode extension can also be sandwiched between the fixing structures on both sides and the positive electrode component 607 and the negative electrode component 608 as needed.

[0096] Positive electrode component 607 and negative electrode component 608, as shown Figure 13 and Figure 14 As shown, both the positive and negative electrode components are cylindrical, with their inner surfaces that contact the cation electrode connection portion and the anion electrode connection portion and / or the cation electrode extension portion and the anion electrode extension portion being planar to increase the contact area. The positive electrode conductive device 1101 and the negative electrode conductive device 1103 extend into the positive and negative electrode components from the outside, for example, from the top, or from other locations. Optionally, in this embodiment, the upper part of the positive electrode component has a first recess 1105, and the upper part of the negative electrode component has a second recess 1107, such that the protruding sealing portion 1605 of the top support plate is inserted into the first and second recesses and seals the positive electrode conductive device 1101 and the negative electrode conductive device 1103 therein. Optionally, the positive electrode component is connected to the outer casing via a gasket 1109, and the negative electrode component is connected to the outer casing via another gasket 1111, thereby achieving a tight connection with the casing. Of course, the positive electrode conductive device 1101 and the negative electrode conductive device 1103 can also be connected to the positive electrode component and the negative electrode component in a suitable manner.

[0097] The top plate 617 and the top support plate 619 are located on top of the acrylic block 605 and the connecting strip 623 of the fixed structure. (As shown) Figure 18As shown, the top support plate 619 includes a main body 1601, on which a plurality of mounting recesses 1603 are formed, for setting the fixing posts to be clamped into the mounting recesses when mounted to help positioning. The main body 1601 further includes sealing portions 1605, as shown, two of which are used to sealingly couple the positive and negative components with the external positive and negative conductive devices. Specifically, the sealing portions 1605 are in the form of protrusions with hollow portions, the inner diameter of which is preferably equivalent to the outer diameter of the positive and negative conductive devices, for inserting the positive and negative conductive devices therein. The top support plate 619 further has a through hole 1607, through which the liquid to be treated enters from the pipeline when mounted. As shown, Figure 19 As shown, the protruding sealing portions are inserted into the first recessed portion 1105 of the positive component and the second recessed portion 1107 of the negative component to form a sealing structure, and the positive and negative conductive devices 1101 and 1103 pass through the hollow structure in the sealing portions 1605, thereby supplying power to the positive and negative components, while the sealing protects the positive and negative conductive devices 1101 and 1103 from being eroded by the medium.

[0098] A bottom support plate is mounted below the MCDI electrode assembly opposite to the top support plate, which is similar to the top support plate, and can also be slightly different.

[0099] The top plate 617 and the bottom plate 615 are arranged outside the top support plate 619 and the bottom support plate 613, and are connected by a peripheral shell 611 located on the outer side thereof, which can be detachably connected for easy replacement, or sealingly connected, for example, by bolt sealing, by buckle sealing, by hinged sealing, etc. As shown, Figure 7 As shown, the top plate, the bottom plate, and the peripheral shell 611 are connected together by screws for sealing. Preferably, gaskets, such as non-conductive gaskets, such as silicone gaskets, are arranged at the joints of the peripheral shell and the top support plate 619 and the bottom support plate 613, respectively, for waterproof sealing between the peripheral shell and the top support plate and between the peripheral shell and the bottom support plate.

[0100] When mounted, a plurality of MCDI electrode assemblies are arranged on each layer of MCDI electrode assemblies, by overlapping arrangement. As shown, Figure 8 and Figure 9As shown, the anion electrode extension and the cation electrode extension on each MCDI electrode assembly extend towards both sides for power supply. The through hole is located in the middle of the MCDI electrode assembly for medium flow. Two fixing structures are located on both sides respectively, the upper part of the fixing structure respectively passes through the openings of the plurality of anion electrode extensions and cation electrode extensions in the combination of the multi-layer MCDI electrode assembly, and the lower surface of the upper part is in contact with the upper surface of the lower part of the fixing structure. The positive part coupled with the positive conductive device is in contact with the alternating anion electrode connecting part and cation electrode connecting part and / or anion electrode extension and cation electrode extension of the plurality of MCDI electrode assemblies to realize the conduction of the anion electrode / cation electrode, and the negative part on the other side coupled with the negative conductive device is in contact with the alternating cation electrode connecting part and anion electrode connecting part and / or cation electrode extension and anion electrode extension of the plurality of MCDI electrode assemblies to realize the conduction of the cation electrode / anion electrode.

[0101] According to the embodiments of the present application, the MCDI module is tested in constant current mode, in which a constant current is applied by a direct current power supply. A current density, for example, 1.0 mA / cm 2 , 1.5 mA / cm 2 , and 2.0 mA / cm 2 , can be applied. The influent TDS is nominally 2000 ppm. At the beginning of the charge cycle, the TDS rapidly decreases to ΔTDS, at which point the effluent water with constant TDS (900 ppm) can be collected as shown in Figure 4 . The charge cycle is typically performed in use until the electrode voltage reaches 1.4 V, at which point the applied current is switched off for a few seconds, and the effluent TDS slowly increases to the influent TDS. A discharge current opposite in direction to the charge current is then applied. The effluent TDS rapidly increases and again remains constant during the discharge phase.

[0102] In the MCDI module of the present application, the design of the fixing structure divided into two parts, the positive part and the negative part, and the positive conductive device 11 and the negative conductive device 21 can effectively ensure that the contact resistance is lower than 24 MΩ, as low as 8.5 MΩ. When the number of electrodes is 19 pairs and the applied current is 8.3 A, it can be ensured that the instantaneous voltage rise or drop is lower than 0.45 V, even as low as 0.20 V, during the charging and discharging. When 19 pairs of electrodes are charged and discharged at a current of 16.6 A and a speed of 880 mL / min, and the influent salinity of a single module is 2000 ppm, the overall design of the module ensures that the salt adsorption capacity (SAC) is at least 10 mg / g, and the charging efficiency (CE) is at least 80%. Using the device described in the present application, the SAC and CE of 19 pairs of electrodes are as high as 18 mg / g and 85%, respectively.

[0103] The MCDI module described in the application reduces the structural complexity of the module, solves the problem of low production efficiency, ensures that the contact resistance between the power supply and the single electrode is low, ensures that the metal conductor is completely sealed, and ensures that the flow channels between the flow electrodes are uniform. The device and method of the application can effectively realize the application of groundwater desalination, wastewater recovery, etc., such as the recovery of sewage from power plants, washing wastewater or other industrial wastewater.

[0104] The word "comprise" as used in this specification means "at least partially comprising". In interpreting each statement in this specification that includes the word "comprise", there is also to be taken into account that the word "comprise" is to be interpreted inclusively, such that the method, product or composition comprising the features of the statement also covers the features of the statement other than the word "comprise" and any preceding description. Related terms such as "comprises" and "comprising" are to be interpreted in the same manner.

[0105] Many modifications in addition to those described above can be made to the application without departing from the scope thereof as defined by the appended claims. The disclosure and description herein are purely illustrative and are not intended to be limiting in any sense. Where specific integers are mentioned in this specification in reference to known equivalents in the field of the application, these known equivalents are deemed to be incorporated in this document, as if individually set forth.

[0106] As used herein, the term "and / or" means "and" or "or" or both.

[0107] In the description of the application in this specification, reference can be made to subjects that are not within the scope of the appended claims. Such subjects should be readily identifiable by those skilled in the art and can be helpful in putting the application as defined in the appended claims into practice.

[0108] Although the application is broadly defined as above, the skilled person will appreciate that the application is not limited thereto and that the application also includes the embodiments exemplified by the following examples.

[0109] The foregoing description of the application includes preferred forms thereof. Modifications can be made to it without departing from the scope of the application.

Claims

1. A membrane capacitive deionization electrode assembly, characterized by, The membrane capacitive deionization electrode assembly comprises, a flexible anion electrode for attracting anions in the liquid to be treated in the channel; a cation exchange membrane disposed adjacent to the anion electrode for passing anions and preventing cations from passing; a cation exchange membrane spaced apart from the anion exchange membrane by the channel for passing cations and preventing anions from passing; and a flexible cation electrode disposed adjacent to the cation exchange membrane for attracting cations in the liquid to be treated in the channel; a spacer in the flow path of the liquid between the anion exchange membrane and the cation exchange membrane for spacing the anion exchange membrane and the cation exchange membrane and guiding the flow of the liquid; wherein the anion electrode comprises at least one anion electrode extension extending outwardly from an edge in the anion electrode, wherein the cation electrode comprises at least one cation electrode extension extending outwardly from an edge in the cation electrode, the directions of extension of the anion electrode extension and the cation electrode extension being opposite to each other, wherein the cation electrode extension comprises an opening and a cation electrode connector inside it, and / or the anion electrode extension comprises an opening and an anion electrode connector inside it, the cation electrode connector being connected to or integral with the cation electrode extension and being able to extend angularly inwardly from the cation electrode extension, the anion electrode connector being connected to or integral with the anion electrode extension and being able to extend angularly inwardly from the anion electrode extension, to facilitate the powering of the cation electrode and / or the anion electrode, the opening being for facilitating the fixing of the membrane capacitive deionization electrode assembly through the opening when installed, wherein the membrane capacitive deionization electrode assembly is configured to be located within a housing structure, the housing structure comprising at least two fixing structures made of non-conductive material, the fixing structures being located within the space enclosed by the peripheral housing and being spaced apart from the positive component and the negative component in the peripheral housing, to facilitate the installation of the electrode assembly, each fixing structure comprising an upper part and a lower part, the lower surface of the upper part being inclined, the upper surface of the lower part being inclined and corresponding to the inclination of the lower surface of the upper part, to facilitate the outward movement of the upper part relative to the lower part along the upper surface of the lower part, and wherein the cation electrode connector is configured to be clamped between the upper part of one fixing structure and the negative component, and the anion electrode connector is configured to be clamped between the upper part of the other fixing structure and the positive component.

2. The membrane capacitive deionization electrode assembly of claim 1, wherein, The cation electrode connector is formed by cutting the cation electrode extension into a tab shape, and the anion electrode connector is formed by cutting the anion electrode extension into a tab shape. The cation electrode connector is formed by cutting the cation electrode extension into a tab shape, and the anion electrode connector is formed by cutting the anion electrode extension into a tab shape.

3. The membrane capacitive deionization electrode assembly of claim 1 or 2, wherein, The cationic electrode and the cationic electrode extension are graphite sheets or metal sheets, and the anionic electrode and the anionic electrode extension are graphite sheets or metal sheets.

4. The membrane capacitive deionization electrode assembly of claim 1 or 2, wherein, the cationic electrode extension includes a cationic electrode edge aperture located adjacent to or in communication with the opening of the cationic electrode extension; and / or the anionic electrode extension includes an anionic electrode edge aperture located adjacent to or in communication with the opening of the anionic electrode extension.

5. The membrane capacitive deionization electrode assembly of claim 1 or 2, wherein, the membrane capacitive deionization electrode assembly includes a through hole to allow treated liquid to flow out of the membrane capacitive deionization electrode assembly via the through hole.

6. A housing structure for an electrode assembly, characterized by, the housing structure includes a top plate located at the top; a bottom plate located at the bottom; a peripheral housing located between the top plate and the bottom plate and connected to the peripheral portions of the top plate and the bottom plate, the top plate, the bottom plate and the peripheral housing forming an interior space for the electrode assembly; positive and negative components located within the space enclosed by the peripheral housing, the positive and negative components being configured to be coupled to a positive and a negative terminal of a power source, respectively, for electrically conductive coupling to the electrodes of the electrode assembly when the electrode assembly is installed; and at least two fixing structures made of non-conductive material, the fixing structures being located within the space enclosed by the peripheral housing and spaced apart from the positive and negative components to facilitate installation of the electrode assembly; wherein the fixing structure includes an upper portion and a lower portion, a lower surface of the upper portion being inclined, and an upper surface of the lower portion being inclined and corresponding to the inclination of the lower surface of the upper portion to facilitate outward movement of the upper portion relative to the lower portion along the upper surface of the lower portion, wherein the upper portion of one of the fixing structures is configured to sandwich an angularly inwardly extending cationic electrode connecting portion of a cationic electrode extension of a cationic electrode between the upper portion of the fixing structure and the negative component, and the upper portion of the other of the fixing structures is configured to sandwich an angularly inwardly extending anionic electrode connecting portion of an anionic electrode extension of an anionic electrode between the upper portion of the fixing structure and the positive component.

7. The housing structure of claim 6, wherein, the housing structure further includes a plurality of fixing posts located within the interior space and between the positive and negative components to facilitate installation of the electrode assembly.

8. The housing structure of claim 6, wherein, the upper portion of the fixing structure is fixed to the lower portion at a position offset from the lower portion after the movement of the upper portion.

9. The enclosure structure of any one of claims 6-8, wherein, the upper portion of the fixing structure includes an aperture for fixing the upper portion to the lower portion through the aperture.

10. The housing structure of claim 9, wherein, the aperture includes two circular apertures and a long strip-shaped aperture located between the two circular apertures.

11. The enclosure structure of any one of claims 6-8, wherein, the interior-facing surfaces of the positive and negative components are planar, and the surfaces of the fixing structures opposite to the positive and negative components are planar.

12. The enclosure structure of any one of claims 6-8, wherein, The housing structure further comprises a gasket between the top plate and the peripheral housing and / or between the bottom plate and the peripheral housing.

13. The enclosure structure of any one of claims 6-8, wherein, The housing structure further comprises a positive electrode conductive device coupled with the positive electrode component and a negative electrode conductive device coupled with the negative electrode component.

14. The enclosure structure of any one of claims 6-8, wherein, The housing structure is connected with the positive electrode conductive device and the negative electrode conductive device, the positive electrode conductive device is coupled with the positive electrode component via one of the top plate, the bottom plate and the peripheral housing, and the negative electrode conductive device is coupled with the negative electrode component via one of the top plate, the bottom plate and the peripheral housing.

15. The enclosure structure of claim 13, wherein, The positive electrode conductive device and the negative electrode conductive device are respectively coupled with the positive electrode component and the negative electrode component in a sealed manner to avoid contact with the liquid to be treated in the housing structure.

16. A module comprising at least one membrane capacitive deion electrode assembly according to any one of claims 1 to 5 and a housing structure according to any one of claims 6 to 15, characterized in that, The membrane capacitive deionization electrode assembly is provided on the bottom plate, the anion electrode extension and / or the anion electrode connecting part contact the positive electrode component of the housing structure, and the cation electrode extension and / or the cation electrode connecting part contact the negative electrode component of the housing structure.

17. The module of claim 16, wherein, The number of the membrane capacitive deionization electrode assemblies is two or more, and the plurality of membrane capacitive deionization electrode assemblies are sequentially stacked to form a group of membrane capacitive deionization electrode assemblies or a plurality of groups of membrane capacitive deionization electrode assemblies, wherein each membrane capacitive deionization electrode assembly is sequentially arranged in the housing structure in a forward and reverse alternating manner.

18. The module of claim 16, wherein, Further comprising a partition plate, the plurality of groups of membrane capacitive deionization electrode assemblies are arranged as a multi-layer structure, and each layer is separated by a partition plate.

19. The module of claim 16, wherein, Further comprising a top support plate, the main body of the top support plate comprises at least one sealing part, the sealing part is a protrusion with a hollow part, by inserting at least one of the positive electrode conductive device and the negative electrode conductive device into the hollow part, and embedding the protrusion into the top opening of at least one of the positive electrode component and the negative electrode component, so that at least one of the positive electrode conductive device and the negative electrode conductive device is sealingly coupled with at least one of the positive electrode component and the negative electrode component.

20. The module of claim 19, wherein, The main body of the top support plate comprises a plurality of mounting recesses, the mounting recesses are used to set the fixing column to be clamped into the mounting recesses when mounted to help positioning.

21. A method for treating a liquid to be treated using the membrane capacitive deionization electrode assembly according to any one of claims 1-5 or the module according to any one of claims 16-20, characterized in that, After the membrane capacitive deionization electrode assembly is powered on, the liquid to be treated flows through the membrane capacitive deionization electrode assembly, so that anions and cations are adsorbed to the anion electrode and the cation electrode.

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