Pole chamber isolation type bipolar membrane electrodialysis membrane assembly

Abstract

The utility model discloses a pole chamber isolation type bipolar membrane electrodialysis membrane component, which comprises an anode region, a cathode region, a core membrane module region, an anode isolation region and a cathode isolation region, the anode region is an anode assembled with an electrode plate, the cathode region is a cathode assembled with an electrode plate, and the core membrane module region is a core membrane module. The core membrane group area comprises a bipolar membrane, a partition plate, a cathode membrane and an anode membrane which are formed by staggered stacking, the anode isolation area is an anode isolation chamber assembled between the anode area and the core membrane group area, and the cathode isolation area is a cathode isolation chamber assembled between the core membrane group area and the cathode area. The anode isolation region and the cathode isolation region isolate a feed liquid chamber and an electrode chamber of electrodialysis, so that certain ions adverse to an electrode (or easy to damage the electrode due to poor electrode reaction) in the feed liquid are effectively prevented from entering the electrode chamber, the corrosion and damage of the ions to the electrode are reduced, and the continuous operation of an electrodialysis assembly is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field, in particular to an electrode chamber isolation type bipolar membrane electrodialysis membrane component. Background Art

[0002] Bipolar membrane electrodialysis (BMED) is an advanced membrane separation technology developed based on the basic principles of traditional electrodialysis. It is primarily used for the efficient separation and conversion of electrolytes in solutions. The core of this technology is to utilize the potential difference under the action of a DC electric field to drive the entire electrodialysis system, achieving effective separation and purification of target substances.

[0003] The operation of the bipolar membrane electrodialysis membrane assembly includes three processes:

[0004] 1. Electrodialysis Process: Under the influence of a DC electric field, charged ions (such as sodium and chloride ions) in the solution selectively pass through the ion exchange membrane. Positively charged cations migrate toward the cathode, passing through the cation exchange membrane and entering the concentrating chamber on the right. Negatively charged anions migrate toward the anode, passing through the anion exchange membrane and entering the concentrating chamber on the left. During this process, sodium chloride is continuously removed from the salt water, forming fresh water in the desalination chamber.

[0005] 2. Bipolar membrane water dissociation: The bipolar membrane is composed of a cation exchange layer, an interfacial hydrophilic layer, and an anion exchange layer. Under the action of a DC electric field, the bipolar membrane can dissociate water, producing hydrogen ions and hydroxide ions on both sides of the membrane.

[0006] 3. Acid-Base Generation: Utilizing the water dissociation properties of bipolar membranes, they are combined with other anion and cation exchange membranes to form a bipolar membrane electrodialysis system. When ions in the bipolar membrane migrate toward the bulk solution, the water in the intermediate layer dissociates into hydrogen ions and hydroxide ions, which carry the current. The hydrogen ions and hydroxide ions migrate toward the bulk solution on either side of the membrane, converting the salt in the aqueous solution into its corresponding acid and base without introducing any new components.

[0007] If the anion and cation membranes form precipitation, scaling or blockage during operation, resulting in increased component voltage and temperature, or if the electrode membranes are damaged due to improper operation, if there are multivalent metal ions in the system, these ions may precipitate on the electrode plates, causing scaling of the electrode plates, affecting the conductivity and processing efficiency of the electrodes. If not discovered in time, it will affect the performance and life of the electrode plates. Utility Model Content

[0008] Therefore, it is necessary to provide a bipolar membrane electrodialysis membrane assembly with isolated electrode chambers to solve the problem that the performance and life of the electrode plates are affected by fouling that is not cleaned in time.

[0009] To achieve the above-mentioned purpose, the present invention provides an electrode chamber isolated bipolar membrane electrodialysis membrane assembly, comprising an anode region, a cathode region, a core membrane group region, an anode isolation region and a cathode isolation region, wherein the anode region is an anode equipped with an electrode plate, the cathode region is a cathode equipped with an electrode plate, the core membrane group region comprises a bipolar membrane, a separator, a cathode membrane and a cathode membrane stacked in an alternating manner, the anode isolation region is an anode isolation chamber installed between the anode region and the core membrane group region, and the cathode isolation region is a cathode isolation chamber installed between the core membrane group region and the cathode region.

[0010] Furthermore, the anode isolation chamber and the cathode isolation chamber are filled with grids for diversion.

[0011] Furthermore, the grille is made of PVC, PP, PE or PPH.

[0012] Furthermore, the core membrane group area includes at least two groups of membrane pairs, each group of membrane pairs includes a bipolar membrane, a gridded partition, an ion exchange anion membrane, and an ion exchange cation membrane, wherein the gridded partition has sealing properties to form a bipolar membrane electrodialysis chamber.

[0013] Furthermore, it also includes a DC power supply for outputting DC power, and the positive pole and negative pole of the DC power supply are connected to the anode area and the cathode area respectively.

[0014] Furthermore, the anode area, the cathode area, the core membrane group area, the anode isolation area and the cathode isolation area are located in a shell, and the anode isolation area and the cathode isolation area are provided with openings at positions corresponding to the shell, and valves for opening and closing are provided at the opening positions.

[0015] The above technical solution has the following beneficial effects:

[0016] The anode isolation area and the cathode isolation area isolate the electrodialysis feed chamber and the electrode chamber, effectively preventing certain ions in the feed that are detrimental to the electrodes (or prone to causing adverse electrode reactions and damaging the electrodes) from entering the electrode chamber, reducing the corrosion and damage caused by these ions to the electrodes, and ensuring the continuous operation of the electrodialysis components. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of the polar chamber isolated bipolar membrane electrodialysis membrane assembly of this embodiment;

[0018] Figure 2 Schematic diagram of the structure of the grille according to this embodiment;

[0019] Figure 3 This is a diagram showing the effect of the presence or absence of a grid on the internal fluid distribution and velocity as simulated in this embodiment;

[0020] Figure 4 1 is an exploded view of the polar chamber isolated bipolar membrane electrodialysis membrane assembly of this embodiment;

[0021] Figure 5 It is a front view of the housing described in this embodiment;

[0022] Figure 6 It is a three-dimensional diagram of the shell described in this embodiment.

[0023] Description of reference numerals:

[0024] 1. Positive electrode;

[0025] 2. Negative electrode;

[0026] 3. Bipolar membrane;

[0027] 4. Partition;

[0028] 5. Vaginal membrane;

[0029] 6. Yang membrane;

[0030] 7. Extreme liquid;

[0031] 8. Polar membrane;

[0032] 9. Acid;

[0033] 10. Alkali;

[0034] 11. Salt;

[0035] 12. Isolation fluid;

[0036] 13. Grille;

[0037] 14. DC power supply;

[0038] 15. Extreme water board;

[0039] 16. Polar chamber membrane package;

[0040] 17. Water distribution board;

[0041] 18. Cathode membrane package;

[0042] 19. Middle plate;

[0043] 20. Negative electrode membrane package;

[0044] 21. Water distribution board;

[0045] 22. Polar chamber membrane package;

[0046] 23. Extreme water board;

[0047] 24. Acid chamber outlet;

[0048] 25. Salt room exit;

[0049] 26. Alkali chamber outlet;

[0050] 27. Exit of the isolation room;

[0051] 28. Exit of polar chamber;

[0052] 29. Shell. DETAILED DESCRIPTION

[0053] In order to explain the technical content, structural features, achieved objectives and effects of the technical solution in detail, the following is a detailed description in conjunction with specific embodiments and accompanying drawings.

[0054] See also Figure 1 This embodiment provides an electrode-chamber-isolated bipolar membrane electrodialysis membrane assembly, comprising an anode region, a cathode region, a core membrane group region, an anode isolation region and a cathode isolation region, wherein the anode region is an anode equipped with an electrode plate, the cathode region is a cathode equipped with an electrode plate, the core membrane group region comprises a bipolar membrane 3, a separator 4, a cathode membrane and a cathode membrane 6 stacked in an alternating manner, the anode isolation region is an anode isolation chamber installed between the anode region and the core membrane group region, and the cathode isolation region is a cathode isolation chamber installed between the core membrane group region and the cathode region.

[0055] A cation exchange membrane (CEM) allows cations to pass through while blocking anions. An anion exchange membrane (AEM) allows anions to pass through while blocking cations. A bipolar membrane (BPM) is composed of a cation exchange layer and an anion exchange layer. When a voltage is applied, it can generate acid and base on both sides of the membrane. The compartment formed by the electrode and membrane is called the polar compartment.

[0056] When a DC power supply 14 is applied to the component, the ions in the electrolyte solution will move under the action of the DC electric field. Positively charged cations migrate toward the cathode through the cation membrane 6, while negatively charged anions migrate toward the anode through the cathode membrane. The anode isolation area uses a special cathode membrane to prevent positively charged calcium, magnesium, organic matter and other ions from entering the cathode. The cathode isolation area uses a special cation membrane 6 to prevent negatively charged fluoride ions and organic matter from entering the cathode chamber. Through the separate circulation system of the isolation area, the electrodialysis feed chamber and the electrode chamber are isolated, effectively preventing certain ions in the feed that are detrimental to the electrode (or prone to adverse electrode reactions and damage the electrode) from entering the electrode chamber, reducing the corrosion and damage caused by these ions to the electrode, and ensuring the continuous operation of the electrodialysis component.

[0057] See also Figure 2In this embodiment, the anode and cathode isolation chambers are filled with flow-guiding grids 13. The presence of the grids 13 helps to evenly distribute the flow of liquid (isolation liquid) through the isolation chambers, reducing the risk of local overheating and electrode plate scaling.

[0058] In this embodiment, the grid 13 is made of PVC (polyvinyl chloride), PP (polypropylene), PE (polyethylene), or PPH (modified polypropylene). These materials have excellent corrosion resistance and are resistant to various chemicals that may be present during the electrodialysis process, thereby extending the service life of the grid 13. The enhanced durability of the grid 13 reduces the frequency of replacement and maintenance, thereby reducing maintenance costs.

[0059] See also Figure 3 , Figure 3 The figure shows the effect of the presence or absence of a grid on the internal fluid distribution and velocity. The left sub-figure is without a grid, and the right sub-figure is with a grid.

[0060] In this embodiment, the core membrane group includes at least two groups of membrane pairs, each group of membrane pairs includes a bipolar membrane 3, a gridded partition 4, an ion exchange anion membrane, and an ion exchange cation membrane 6, wherein the gridded partition 4 has sealing properties to form a bipolar membrane 3 electrodialysis chamber, ensuring the integrity of the chamber and the directional flow of the fluid, and avoiding cross-contamination between different chambers.

[0061] In this embodiment, the core membrane group area can use two membrane pairs, or can use three membrane pairs, four membrane pairs, five membrane pairs, etc.

[0062] See also Figure 1 In this embodiment, the polar chamber isolated bipolar membrane electrodialysis membrane assembly further includes a DC power supply 14, wherein the positive electrode 1 and the negative electrode 2 of the DC power supply 14 are connected to the anode region and the cathode region, respectively. The DC power supply 14 is used to provide a stable DC voltage and provide the necessary potential difference for the electrodialysis assembly so that the ions in the electrolyte solution can migrate to the corresponding electrode region according to the difference in charge. The positive electrode 1 of the DC power supply 14 is connected to the anode region, which is usually made of anode material and can promote the occurrence of anode reactions (such as oxidation reactions). The negative electrode 2 of the DC power supply 14 is connected to the cathode region, which is usually made of cathode material and can promote the occurrence of cathode reactions (such as reduction reactions).

[0063] See also Figure 1 In this embodiment, there is a polar liquid 7 between the positive electrode 1 and the polar membrane 8, an isolation liquid 12 between the polar membrane 8 and the cation membrane 6, an alkali 10 between the cation membrane 6 and the bipolar membrane 3, an acid 9 between the bipolar membrane 3 and the anion membrane 5, a salt 11 between the anion membrane 5 and the cation membrane 6, an alkali 10 between the cation membrane 6 and the bipolar membrane 3, and an alkali 10 between the cation membranes 6 and the cation membranes 6.

[0064] In this embodiment, the anode region, the cathode region, the core membrane group region, the anode isolation region and the cathode isolation region are located in a shell, and the anode isolation region and the cathode isolation region are provided with openings at positions corresponding to the shell, and valves for opening and closing are provided at the opening positions. The shell is used to accommodate the anode region, the cathode region, the core membrane group region, the anode isolation region and the cathode isolation region, providing a closed space to help protect the internal components from the external environment. The anode isolation region and the cathode isolation region are provided with openings on the shell for the entry and exit of liquid or gas to ensure that the liquid can smoothly enter and flow out of the isolation region. Specifically, Figure 5 The housing 29 is shown to have an acid chamber outlet 24 , a salt chamber outlet 25 , an alkali chamber outlet 26 , an isolation chamber outlet 27 , and a pole chamber outlet 28 .

[0065] In this embodiment, Figure 4 An exploded view of the electrode-chamber isolated bipolar membrane electrodialysis membrane assembly is shown, which includes, from top to bottom, the positive electrode 1 (carbon steel plate), the electrode water plate 15, the electrode chamber membrane package 16, the water distribution plate 17 (including the isolation chamber), the positive electrode membrane package 18, the intermediate plate 19, the negative electrode membrane package 20, the water distribution plate 21 (including the isolation chamber), the electrode chamber membrane package 22, the electrode water plate 23, and the negative electrode 2 (carbon steel plate).

[0066] It should be noted that, in this document, relational terms such as first and second, etc., are used solely to distinguish one entity or operation from another, and do not necessarily require or imply any actual relationship or order between these entities or operations. Furthermore, the terms "include," "comprise," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or terminal device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. Without further limitation, elements defined by the phrase "include..." or "comprising..." do not exclude the presence of additional elements in the process, method, article, or terminal device comprising the elements. Furthermore, in this document, "greater than," "less than," "exceeding," etc., are understood to exclude the number itself; "above," "below," "within," etc., are understood to include the number itself.

[0067] Although the above embodiments have been described, those skilled in the art may make additional changes and modifications to these embodiments once they know the basic creative concepts. Therefore, the above description is only an embodiment of the present invention and does not limit the scope of patent protection of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of the present invention, or directly or indirectly used in other related technical fields, are also included in the scope of patent protection of the present invention.

Claims

1. A bipolar membrane electrodialysis membrane assembly with isolated polar chambers, characterized in that: It includes an anode area, a cathode area, a core membrane group area, an anode isolation area and a cathode isolation area. The anode area is an anode equipped with an electrode plate, the cathode area is a cathode equipped with an electrode plate, the core membrane group area includes a bipolar membrane, a separator, a cathode membrane and a cathode membrane stacked in an alternating manner, the anode isolation area is an anode isolation chamber installed between the anode area and the core membrane group area, and the cathode isolation area is a cathode isolation chamber installed between the core membrane group area and the cathode area.

2. The assembly according to claim 1, characterized in that The anode isolation chamber and the cathode isolation chamber are filled with grids for diversion.

3. The assembly according to claim 2, characterized in that The material of the grille is PVC, PP, PE or PPH.

4. The assembly according to claim 1, wherein The core membrane group area includes at least two groups of membrane pairs, each group of membrane pairs includes a bipolar membrane, a gridded partition, an ion exchange anion membrane, and an ion exchange cation membrane, wherein the gridded partition has sealing properties to form a bipolar membrane electrodialysis chamber.

5. The assembly according to claim 1, characterized in that It also includes a DC power supply for outputting DC power, wherein the positive pole and the negative pole of the DC power supply are connected to the anode area and the cathode area respectively.

6. The assembly according to claim 1, characterized in that The anode area, the cathode area, the core membrane group area, the anode isolation area and the cathode isolation area are located in a shell. The anode isolation area and the cathode isolation area are provided with openings at positions corresponding to the shell, and valves for opening and closing are provided at the opening positions.

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