Sealing assembly for alkaline water electrolyzer, electrolysis unit and electrolyzer

Abstract

The utility model relates to the technical field of electrolysis equipment, in particular to a sealing assembly for an alkaline water electrolysis bath, an electrolysis unit and the electrolysis bath. The sealing assembly comprises a rubber sealing ring, the outer ring side wall of the rubber sealing ring is provided with a circular outer ring groove extending towards the inner ring direction, and a metal framework is embedded in the outer ring groove. The metal framework is arranged on the periphery of the rubber sealing ring, so that the problem that part of the rubber sealing ring is not attached to the preset position due to insufficient rigidity of the rubber sealing ring in the assembling process is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of electrolysis equipment, and more specifically, to a sealing component of an alkaline water electrolysis tank, an electrolysis unit and an electrolysis tank. Background Art

[0002] Alkaline water electrolyzers usually include many parts and structural designs, which are stacked on top of each other. These key components include diaphragms, bipolar plates, cathode and anode electrodes, cathode and anode plate frames, current transmission components, flow channels, seals, etc. An electrolyzer can be made up of 5 to 300 identical electrolytic units stacked together. To simplify installation, the electrolyzer has some nested structures that allow the components to be inserted or stacked together and then pressed together with screws. After the press-fitting is completed, the metal end plate is fixed, which connects to the electrical system and passes the electrolyte and gas pipeline.

[0003] As an important sealing component of the electrolytic cell, rubber seals are related to the overall life and even safety of the electrolytic cell. Traditional PTFE gaskets are prone to inaccurate installation, different compression amounts during heating and tightening, and material creep during long-term operation, which can lead to overall leakage of the sealing groove, short life, and even damage to the electrolytic cell. In addition, the installation process of PTFE gaskets is very complicated. The installation of traditional electrolytic cells takes about 14 days or more, and the production efficiency is extremely low.

[0004] Later, PTFE gaskets were gradually replaced by rubber seals, but the rubber seal alternative still has the following technical difficulties: the diaphragm is easily deformed due to stress, pulling or compression during the rubber molding process; the diaphragm is prone to wrinkles and displacement during the rubber vulcanization process.

[0005] In addition, the diameter of the rubber seal is generally much larger than its thickness, which can easily lead to insufficient rigidity. During the assembly process of the electrolytic cell, it is easy to produce large deformations, causing some parts to not fit in the preset position, affecting the sealing of the electrolytic cell. Utility Model Content

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a sealing assembly for an alkaline water electrolyzer, which at least overcomes the problem that a rubber sealing ring does not fit in a preset position due to its own insufficient rigidity during assembly.

[0007] The above technical objectives of the utility model are achieved through the following technical solutions:

[0008] A sealing assembly for an alkaline water electrolyzer comprises a rubber sealing ring, an outer ring side wall of which is provided with a circular outer ring groove extending toward an inner ring direction, and a metal frame is inlaid on the outer ring groove.

[0009] Optionally, an inner ring side wall of the rubber sealing ring is provided with an inner ring groove extending toward the outer ring and having a circular shape, and a diaphragm is embedded in the inner ring groove.

[0010] Optionally, a hard frame is provided on the outer edge of the diaphragm to prevent the diaphragm from deforming and is located in the inner ring groove.

[0011] Optionally, an arc-shaped groove is provided on one side of the rubber sealing ring, a gas-liquid through hole is provided on the rubber sealing ring for directing the gas generated by electrolysis to the outside or the electrolyte to the inside, and a circular boss is provided on the other side of the rubber sealing ring to match the arc-shaped groove to form a mortise and tenon structure; the arc-shaped groove, the gas-liquid through hole and the circular boss cooperate with each other to form an integrated flow channel; at least two integrated flow channels that penetrate the rubber sealing ring are provided on the rubber sealing ring, at least one integrated flow channel is located at the upper end of the rubber sealing ring, and at least one integrated flow channel is located at the lower end of the rubber sealing ring.

[0012] Optionally, an anti-blocking boss is provided on the arc-shaped groove to prevent the integrated flow channel from being blocked.

[0013] Optionally, the annular boss is concentrically arranged with the gas-liquid through hole, and the inner ring diameter of the annular boss is larger than the diameter of the gas-liquid through hole.

[0014] Optionally, a plurality of limiting rings for locking screws to pass through are provided on the metal frame.

[0015] Optionally, a limiting pad is provided on the metal frame, and a plurality of screw holes for the locking screw to pass through are formed on the limiting pad.

[0016] Another object of the utility model is to provide an electrolytic unit for an alkaline water electrolyzer, which comprises: the above-mentioned sealing assembly and a plate composite; the plate composite is embedded in the rubber sealing ring and is located on one side of the diaphragm.

[0017] Another object of the utility model is to provide an electrolytic cell, which includes: a front end plate, an anode plate, a plurality of the above-mentioned electrolytic units, a cathode plate, and a rear end plate stacked in sequence; the front end plate and the rear end plate are locked by a plurality of locking screws, and the front end plate and the rear end plate clamp the anode plate, a plurality of electrolytic units and the cathode plate located therebetween.

[0018] Optionally, at least one gas through hole is provided at the upper end of the front end plate and the upper end of the rear end plate, and at least one electrolyte through hole is provided at the upper end of the front end plate and the lower end of the rear end plate.

[0019] In summary, the utility model has the following beneficial effects: firstly, by arranging a metal frame on the periphery of the rubber sealing ring, the problem of the rubber sealing ring not fitting in the preset position due to its own insufficient rigidity during assembly is overcome; secondly, by embedding a diaphragm with a hard frame on the outer edge into the rubber sealing ring, the problems of the diaphragm being easily deformed, wrinkled and displaced during the molding or vulcanization process are overcome. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram I of the sealing component in the utility model;

[0021] Figure 2 It is the structural schematic diagram II of the sealing assembly in the utility model;

[0022] Figure 3 It is a partial structural schematic diagram of the rubber sealing ring in the utility model;

[0023] Figure 4 It is a structural schematic diagram of the limiting pad in the utility model;

[0024] Figure 5 It is a front view of the sealing assembly in the utility model;

[0025] Figure 6 yes Figure 5 Section view at section AA;

[0026] Figure 7 yes Figure 6 Enlarged view of area B;

[0027] Figure 8 It is a structural schematic diagram of the electrolysis unit in the utility model;

[0028] Fig. 9 It is an exploded view of the electrolysis unit in the utility model;

[0029] Fig.10 It is a diagram of the stacking state of several electrolytic units in the utility model;

[0030] Fig.11 It is a structural schematic diagram of the electrolytic cell in the utility model.

[0031] In the figure: 1. rubber sealing ring; 11. first circular groove; 12. first circular boss; 13. arc groove; 14. gas-liquid through hole; 15. circular boss; 16. anti-blocking boss; 17. integrated flow channel; 2. diaphragm; 3. hard skeleton; 4. metal skeleton; 41. limit ring or limit pad; 411. screw hole; 5. plate complex; 6. electrode unit; 7. front end plate; 71. gas through hole; 72. electrolyte through hole; 8. rear end plate; 9. locking screw. DETAILED DESCRIPTION

[0032] In order to make the purpose, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. Several embodiments of the utility model are given in the accompanying drawings. However, the utility model can be implemented in many different forms and is not limited to the embodiments described herein.

[0033] In the present utility model, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances. The terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0034] The utility model is described in detail below in conjunction with the accompanying drawings and embodiments.

[0035] The utility model provides a sealing component for an alkaline water electrolyzer, comprising: a rubber sealing ring 1, an inner ring groove (not shown in the attached drawings) extending in a circular direction toward an outer ring is provided on the inner ring side wall of the rubber sealing ring 1, a diaphragm 2 is embedded in the inner ring groove, a hard skeleton 3 is arranged on the outer edge of the diaphragm to prevent the diaphragm 2 from deforming and is located in the inner ring groove; an outer ring groove extending in a circular direction toward an inner ring is provided on the outer ring side wall of the rubber sealing ring, and a metal skeleton 4 (not shown in the attached drawings) is embedded in the outer ring groove.

[0036] like Figure 1-7 As shown, the rubber sealing ring 1 is a circular gasket with a thickness of about 8-9mm. It is made of one or a combination of two or more of ethylene propylene rubber, EVA rubber, natural rubber, chloroprene rubber, ethylene-vinyl acetate rubber, chlorinated polyethylene rubber, polyacrylate rubber, ethylene acrylate rubber, nitrile rubber, and fluororubber. Of course, it can also be made of modified rubber with excellent heat resistance, alkali resistance, heat oxidation resistance, hot water resistance, and insulation. The diaphragm is not limited to the use of PPS material. The hard skeleton 3 is made of high-strength hard plastic or composite plastic, or it can be metal. The diaphragm 2 and the hard skeleton 3 need to be combined before the production of the rubber sealing gasket ring 1 to ensure that the diaphragm 2 is tightly fixed in the ring groove during the production process to avoid misalignment between the rubber material and the diaphragm during the molding or vulcanization process. The metal skeleton 4 can be integrally formed during rubber vulcanization, or it can be installed later.

[0037] The depth of the outer ring groove is greater than the position of the gas-liquid guide hole at the periphery. The metal skeleton does not reach the position of the gas hole. Only on the periphery of this skeleton, there are through holes for the later insertion and fixing of the electrolytic cell screws. This prevents the generated gas or electrolyte from causing premature aging and corrosion of the metal.

[0038] The utility model overcomes the problems of easy deformation, wrinkling and displacement of the diaphragm 2 during the molding or vulcanization process by embedding the diaphragm 2 with a hard skeleton 3 on the outer edge into the rubber sealing ring 1. In addition, the sealing assembly with the integrated diaphragm 2 is installed in the alkaline water electrolyzer as a sealing gasket, which simplifies the installation process and improves the installation efficiency. By arranging a metal skeleton on the periphery of the rubber sealing ring, the problem of the rubber sealing ring not fitting in the preset position due to its own insufficient rigidity during the assembly process is overcome.

[0039] During production, the diaphragm 2 and the hard skeleton 3 are preformed into a semi-finished part, and then the semi-finished part and the metal skeleton 4 are respectively assembled on the inner ring groove and the outer ring groove of the rubber sealing ring 1, and the formed integral part is the sealing component for the alkaline water electrolyzer. In addition, in order to improve the connection strength between the diaphragm 2 and the rubber sealing ring 1 and save the assembly process, the semi-finished part and the metal skeleton 4 can be placed in the molding mold of the rubber sealing ring 1, and integrally molded with the rubber material to obtain a sealing component.

[0040] Furthermore, an arc-shaped groove 13 is provided on one side of the rubber sealing ring 1, a gas-liquid through hole 14 is provided on the rubber sealing ring 1 for guiding the gas generated by electrolysis to the outside or the electrolyte to the inside, and a circular ring boss 15 is provided on the other side of the rubber sealing ring 1 to adapt to the arc-shaped groove 13 to form a mortise and tenon structure; the arc-shaped groove 13, the gas-liquid through hole 14 and the circular ring boss 15 cooperate with each other to form an integrated flow channel 17; at least two integrated flow channels 17 that penetrate the rubber sealing ring 1 are provided on the rubber sealing ring 1, at least one integrated flow channel 17 is located at the upper end of the rubber sealing ring 1, and at least one integrated flow channel 17 is located at the lower end of the rubber sealing ring 1.

[0041] Furthermore, an anti-blocking boss 16 is provided on the arc-shaped groove 13 to prevent the integrated flow channel 17 from being blocked.

[0042] The rubber sealing ring 1 is divided into two sides, the front side and the back side, both of which have a groove flow channel structure and a boss structure. Figure 1 is the front side of the rubber sealing ring 1, such as Figure 2 It is the reverse side of the rubber sealing ring 1, and two integrated flow channels 17 are provided at the upper and lower ends of the front side. The integrated flow channel 17 at the upper end is mainly for hydrogen and oxygen to pass through, and the integrated flow channel 17 at the lower end is mainly for electrolyte to pass through.

[0043] The depth of the arc groove 13 is about 2-3mm, and its width is greater than the diameter of the gas-liquid through hole 14. The arc groove 13 is embedded with an anti-blocking boss 16 to prevent the integrated flow channel 17 from being blocked. The anti-blocking boss 16 is 1-2mm high and is not connected to the gas-liquid through hole 14 and the inner ring of the rubber sealing ring 1 to avoid stress concentration during compression, which makes the anti-blocking boss 16 easy to damage. The height of the annular boss 15 is 2-3mm, and the outer diameter needs to be smaller than the width of the arc groove 13 to facilitate nesting during installation.

[0044] The sealing assembly achieves sealing through rubber compression and nested mortise and tenon structures. The annular boss 15 in the integrated flow channel 17 can prevent the rubber from being compressed too much during installation, resulting in blockage of the flow channel. The compressibility of the rubber can ensure the sealing performance through its own resilience when the electrolytic cell is started and the ambient temperature changes. The embedded structure of the mortise and tenon ensures that there is no leakage of gas and liquid when the entire cell expands and contracts, thereby ensuring the sealing of the entire electrolytic cell.

[0045] Furthermore, the annular boss 15 is concentrically arranged with the gas-liquid through hole 14 , and the inner ring diameter of the annular boss 15 is larger than the diameter of the gas-liquid through hole 14 .

[0046] like Figure 2 As shown, the inner diameter of the annular boss 15 needs to be larger than the diameter of the gas-liquid through hole 14 to prevent the annular boss 15 from blocking the gas-liquid through hole 14 due to extrusion deformation.

[0047] Furthermore, a plurality of limiting rings 41 for the locking screw rods 9 to pass through are provided on the metal frame 4 .

[0048] like Figure 2 As shown, eight through holes are evenly spaced on the metal skeleton 4, and a limit ring 41 is embedded in each through hole. The limit ring 41 is made of PTFE, PSU, PPS, PU and other hard plastics or metals with much higher strength than the sealing rubber ring 1, and its molding method is not limited, and can be compression molding, injection molding or turning. The limit ring 41 is only used as a pressure-bearing and pressure-limiting component, and the compression modulus is not less than 10 times the compression modulus of the rubber sealing ring 1.

[0049] In another embodiment, the eight limiting rings 41 can be made into an integral limiting pad 41 structure, as shown in FIG. Figure 4 As shown, eight screw holes 411 are correspondingly provided on the limiting pad 41 for the locking screw 9 to pass through.

[0050] The purpose of providing the limiting ring 41 or the limiting pad 41 is to prevent the rubber sealing ring 1 from being over-compressed during the assembly process of the electrolytic cell and to facilitate the installation of the locking screw 9 .

[0051] Furthermore, in order to improve the connection strength between the limiting ring 18 and the metal frame 4 and simplify the assembly process, the limiting ring 41 or the limiting pad 41 is integrally formed with the metal frame 4 .

[0052] Another object of the present invention is to provide an electrolytic unit 6 for an alkaline water electrolyzer, which comprises: the above-mentioned sealing assembly and a plate composite 5; the plate composite 5 is embedded in the rubber sealing ring 1 and is located on one side of the diaphragm 2.

[0053] like Figure 8-10 As shown, a groove structure is provided on one side of the rubber sealing ring 1, and the plate complex 5 is embedded in the rubber sealing ring 1 in an integrally formed manner or a post-assembled manner. The plate complex 5 is not tightly fitted with the diaphragm 2, and the generated gas or electrolyte can enter (flow through) the integrated flow channel 17. The plate complex 5 is a bipolar plate and a membrane electrode assembly, and the overall thickness is about 1-2 mm. Its structure and connection relationship can be set according to the conventional settings in the field, and will not be described in detail here.

[0054] Another object of the utility model is to provide an electrolytic cell, which includes: a front end plate 7, an anode plate (not shown in the drawings), a plurality of the above-mentioned electrolytic units 6, a cathode plate (not shown in the drawings), and a rear end plate 8 stacked in sequence; the front end plate 7 and the rear end plate 8 are locked by a plurality of locking screws 9, and the front end plate 7 and the rear end plate 8 clamp the anode plate, the plurality of the above-mentioned electrolytic units 6 and the cathode plate located therebetween.

[0055] The front end plate 7 has the same structure as the rear end plate 8, and the material is metal, and the surface coating needs to be corrosion-resistant and hydrogen embrittlement-resistant. The front end plate 7 is used as an example below. The front end plate 7 has a gas through hole 71 and an electrolyte through hole 72 corresponding to the electrolytic unit 6. The gas through hole 71 and the electrolyte through hole 72 cooperate with the integrated flow channel 17 through corresponding pipelines, wherein the gas through hole 71 is located at the upper end of the front end plate 7, and the electrolyte through hole 82 is located at the lower end of the front end plate 7. The principle is that the gas density is less than the liquid density. The front end plate 7 is also provided with assembly holes whose number and position correspond to the limit ring 41 one by one, which are used to cooperate with the limit ring 41 and the locking screw 9 in the electrolytic unit 6. The number of holes needs to be related to the number of press-fitting of the electrolytic cell and the size and quality of the electrolytic cell. The above-mentioned assembly holes are also used as fastening screw holes for pressing the electrolytic unit 6. When the electrolytic cell is installed, the locking screw 9 is passed through the front end plate 7 and the rear end plate 8 to fix multiple electrolytic units 6. Different manufacturers have different ways of connecting internal circuits, and it is necessary to open holes on the front end plate 7 or the rear end plate 8 to connect wires, power-on devices, etc. This is not the invention point of the utility model and will not be elaborated here.

[0056] In summary, the utility model has the following beneficial effects: (1) By embedding the diaphragm 2 with a hard skeleton 3 on the outer edge into the rubber sealing ring 1, the problems of easy deformation, wrinkling and displacement of the diaphragm 2 during the molding or vulcanization process are overcome. (2) By arranging a metal skeleton on the periphery of the rubber sealing ring, the problem of the rubber sealing ring not fitting in the preset position due to its own insufficient rigidity during the assembly process is overcome. (3) The electrolytic cell uses a better rubber sealing material than PTFE, thereby improving the conversion efficiency. It can withstand higher cavity temperatures and higher cavity pressures. In addition, the rubber has a longer-lasting rebound performance, ensuring the long-term reliability of the seal and extending the overall service life. (4) The diaphragm 2 and the plate complex are integrated on the rubber sealing ring 1, simplifying the installation process and reducing the material and installation costs. (5) The rubber sealing ring 1 can effectively prevent vibration, reduce resonance during the start-up and shutdown and operation of the electrolytic cell, and improve its service life.

[0057] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A sealing assembly for an alkaline water electrolyzer, characterized in that: include: A rubber sealing ring, wherein an outer ring groove extending toward the inner ring and in a circular shape is provided on the outer ring side wall of the rubber sealing ring, and a metal frame is inlaid on the outer ring groove.

2. The sealing assembly according to claim 1, characterized in that An inner ring groove extending toward the outer ring and in a circular shape is provided on the inner ring side wall of the rubber sealing ring, and a diaphragm is embedded in the inner ring groove.

3. The sealing assembly according to claim 1, characterized in that A hard frame is arranged on the outer edge of the diaphragm to prevent the diaphragm from deforming and is located in the inner ring groove.

4. The sealing assembly according to claim 3, characterized in that An arc-shaped groove is provided on one side of the rubber sealing ring, a gas-liquid through hole is provided on the rubber sealing ring for guiding the gas generated by electrolysis to the outside or the electrolyte to the inside, and a circular ring boss is provided on the other side of the rubber sealing ring to match the arc-shaped groove to form a mortise and tenon structure; the arc-shaped groove, the gas-liquid through hole and the circular ring boss cooperate with each other to form an integrated flow channel; at least two integrated flow channels that penetrate the rubber sealing ring are provided on the rubber sealing ring, at least one integrated flow channel is located at the upper end of the rubber sealing ring, and at least one integrated flow channel is located at the lower end of the rubber sealing ring.

5. The sealing assembly according to claim 4, characterized in that An anti-blocking boss is arranged on the arc-shaped groove to prevent the integrated flow channel from being blocked.

6. The sealing assembly according to claim 4, characterized in that The annular boss is concentrically arranged with the gas-liquid through hole, and the inner ring diameter of the annular boss is larger than the diameter of the gas-liquid through hole.

7. The sealing assembly according to claim 2, wherein: A plurality of limiting rings for locking screw rods to pass through are arranged on the metal frame.

8. The sealing assembly according to claim 1, wherein: A limiting pad is arranged on the metal frame, and a plurality of screw rod holes for the locking screw rod to pass through are formed on the limiting pad.

9. An electrolysis unit for an alkaline water electrolyzer, characterized in that: include: The sealing assembly and the electrode plate composite according to any one of claims 1 to 7; the electrode plate composite is embedded in the rubber sealing ring and is located on one side of the diaphragm.

10. An electrolytic cell, characterized in that: include: A front end plate, an anode plate, several electrolytic units as claimed in claim 9, a cathode plate, and a rear end plate are stacked in sequence; the front end plate and the rear end plate are locked by several locking screws, and the front end plate and the rear end plate clamp the anode plate, several electrolytic units and the cathode plate therebetween; at least one gas through hole is opened at the upper end of the front end plate and the upper end of the rear end plate, and at least one electrolyte through hole is opened at the upper end of the front end plate and the lower end of the rear end plate.

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