An insulating grid for an electrolytic cell and an electrolytic cell

Abstract

The application discloses an insulating partition net for an electrolytic cell, characterized in that the insulating partition net (4) is used for partitioning between two electrode sheets (3) of the electrolytic cell, the insulating partition net (4) is flat, and a flow channel (40) in a zigzag arrangement is formed on the surface of the insulating partition net (4). The application further discloses an electrolytic cell provided with the insulating partition net. Compared with the prior art, the application can improve the turbulence effect, thereby accelerating exhaust, inhibiting scale deposition and accelerating ion transfer.

Description

Technical Field

[0001] This invention relates to the field of electrolysis equipment technology, specifically to an insulating mesh for an electrolytic cell and an electrolytic cell. Background Technology

[0002] An electrolytic cell consists of a cell body, an anode, and a cathode. Most electrolytic cells use an ion-exchange membrane (also called a diaphragm) to separate the anode and cathode chambers. Based on the type of electrolyte, they are classified into three categories: aqueous solution electrolytic cells, molten salt electrolytic cells, and non-aqueous solution electrolytic cells. When direct current passes through the electrolytic cell, an oxidation reaction occurs at the anode-solution interface, and a reduction reaction occurs at the cathode-solution interface, thus producing electrolyzed water.

[0003] For example, the Chinese invention patent with patent application number CN201810264395.4 (publication number CN108609693A) entitled "A Method for Preparing Acidic Water and Alkaline Water" uses the electrolysis of brine to form cations and anions, which move towards the two electrodes of the electrolysis. Hydrogen ions and highly reactive chlorine gas are generated from the anode. The chlorine gas dissolves in water to form hypochlorous acid and hydrochloric acid solutions as acidic water. Hydroxide ions and hydrogen gas are generated from the cathode to form sodium hydroxide solution as alkaline water.

[0004] The existing water electrolysis process has the following problems:

[0005] First, ion exchange membranes are unique polymer membranes containing ionic groups that selectively allow cations or anions in a solution to pass through. They have a certain degree of flexibility and, over time, can deform under the influence of air and water pressure, or even come into contact with the electrode plates and cause dry burning, affecting the water output and the lifespan of the electrolyzer. These problems are even more serious in small electrolyzers.

[0006] Secondly, during the electrolysis process, a large number of bubbles are generated on the anode and cathode plates. These bubbles accumulate on the electrode plates, ion exchange membranes, and water channels in the electrolytic cell, resulting in high voltage requirements and high energy consumption for the electrolysis system. They also reduce the effective electrolysis area, decrease the electrolysis reaction efficiency, lead to low pH of the effluent, and obstruct the smooth flow of water channels, making the pH value and voltage extremely unstable. The gas pressure will also exacerbate the deformation of the intermediate ion exchange membrane, especially in small electrolytic cells where the above problems are more serious.

[0007] Third, during electrolysis, the OH- generated at the cathode (negative electrode) - It will react with Ca in the water 2+ Mg 2+ The reaction produces scale, which deposits on the cathode and ion exchange membrane, affecting the electrolysis effect and the lifespan of the electrolytic cell.

[0008] Fourth, during electrolysis, ions need to pass through the ion exchange membrane from the anode chamber to the cathode chamber before the entire electrolysis reaction can proceed. However, during the electrolysis reaction, ions and products tend to accumulate around the electrode plates, which is not conducive to the diffusion and transfer of ions and the uniformity of products, thus affecting the electrolysis efficiency and pH stability.

[0009] In addition, the Chinese invention patent "Electrolyte Manufacturing Apparatus and Electrolyte Manufacturing Method" with patent application number CN202080012097.1 (publication number CN113474492A) discloses that a mesh is set between the diaphragm and the electrode plate to separate the diaphragm and the electrode plate, so as to avoid the diaphragm contacting the electrode plate and causing dry burning. Although the water flow can form local micro-turbulence in the process of passing through the mesh, its turbulence effect is limited and it cannot effectively accelerate the exhaust, inhibit scale deposition, accelerate ion transfer, and treat the already deposited scale. Summary of the Invention

[0010] The first technical problem to be solved by the present invention is to provide an insulating mesh for an electrolytic cell that can improve the turbulence effect and thus accelerate exhaust, in view of the current state of the prior art.

[0011] The second technical problem to be solved by the present invention is to provide an insulating mesh for an electrolytic cell that can improve the turbulence effect and thus suppress scale deposition.

[0012] The third technical problem to be solved by the present invention is to provide an insulating mesh for an electrolytic cell that can improve the turbulence effect and thus accelerate ion transfer.

[0013] The fourth technical problem to be solved by the present invention is to provide an electrolytic cell with the above-mentioned insulating mesh.

[0014] The fifth technical problem to be solved by the present invention is to provide an electrolytic cell capable of cleaning and scraping off scale.

[0015] The technical solution adopted by the present invention to solve the first, second and third technical problems mentioned above is: an insulating mesh for an electrolytic cell, characterized in that: the insulating mesh is used to separate two electrode plates in the electrolytic cell, the insulating mesh is flat and has tortuous flow channels formed on its surface.

[0016] To facilitate the formation of the flow channel, the surface of the insulating mesh is provided with a flow guiding structure, which constructs the flow channel.

[0017] The technical solution adopted by the present invention to solve the fourth technical problem is: an electrolytic cell using the above-mentioned insulating mesh.

[0018] To facilitate the installation of the insulating mesh, the electrolytic cell includes a cell body and a diaphragm disposed within the cell body. The diaphragm divides the inner cavity of the cell body into at least two electrode chambers. Each electrode chamber is provided with an electrode plate and an insulating mesh, and the insulating mesh is separated between adjacent diaphragms and electrode plates.

[0019] To facilitate the formation of the flow channel, the insulating mesh is approximately rectangular. The two long sides of the insulating mesh are designated as the first side and the second side, respectively. The surface of the insulating mesh is provided with multiple guide strips arranged at intervals along the long side of the insulating mesh. Each guide strip extends along the short side of the insulating mesh. A flow channel unit is formed between two adjacent guide strips and the inner wall of the tank. The odd-numbered flow channel unit in the arrangement direction is designated as the first flow channel unit, and the even-numbered flow channel unit in the arrangement direction is designated as the second flow channel unit. The first flow channel unit and the second flow channel unit are interconnected near the first side, and the second flow channel unit and the first flow channel unit are interconnected near the second side. All flow channel units together form the flow channel.

[0020] To facilitate communication between two adjacent flow channel units, the guide strips arranged in the direction of arrangement are designated as the first guide strip, and the even-numbered guide strips arranged in the direction of arrangement are designated as the second guide strip. The end of the second guide strip near the first side has a gap with the inner wall of the tank to form a first gap for connecting the preceding first flow channel unit and the following second flow channel unit. The end of the first guide strip near the second side has a gap with the inner wall of the tank to form a second gap for connecting the preceding second flow channel unit and the following first flow channel unit.

[0021] To facilitate the supply of raw materials and the discharge of electrolyzed water, each electrode chamber is provided with an inlet and an outlet that communicate with the electrode chamber in the corresponding tank section.

[0022] To ensure sufficient turbulence around the flow channel, the extension direction of each guide strip is basically perpendicular to the line connecting the inlet and outlet.

[0023] To further address the fifth technical problem mentioned above, the surface of the guide strip is formed with a scraping surface that can rub against adjacent diaphragms or electrode sheets.

[0024] To achieve dynamic turbulence, the following solutions are available:

[0025] In Option 1, the insulating mesh is suspended in the air so that it can move freely under the action of water flow.

[0026] Option 2 also includes a drive mechanism for driving the movement of the insulating mesh.

[0027] To ensure that the insulating mesh has a sufficiently large range of motion, the insulating mesh is arranged parallel to the diaphragm and electrode plates.

[0028] To achieve the driving of the insulating mesh, the driving mechanism includes:

[0029] The first end of the pull rod is connected to the edge of the insulating mesh; and

[0030] The drive unit has a telescopic rod that can extend and retract in a direction parallel to the insulating mesh, and the telescopic rod is connected to the second end of the pull rod.

[0031] To facilitate the installation of the drive mechanism and avoid the electrolyte affecting the service life of the drive component, the drive component is installed on the outside of the tank, and the pull rod passes through the tank from the first end to the second end and is exposed on the outer wall of the tank.

[0032] To simplify the drive mechanism, the number of insulating meshes is at least two, and each drive mechanism corresponds to one insulating mesh. All drive mechanisms share the same drive component.

[0033] To ensure that the insulating mesh fully disturbs the upward-flowing water and improves the disturbance effect, the extension and retraction direction of the telescopic rod is basically perpendicular to the line connecting the inlet and outlet.

[0034] Compared with the prior art, the advantages of the present invention are: by setting the tortuous flow channels on the surface of the flat insulating mesh, the movement path of the water flow in the electrolytic cell is extended. During the tortuous flow of the water, it fully impacts the periphery of the flow channel, achieving sufficient turbulence, which can accelerate exhaust, inhibit scale deposition, and accelerate ion transfer. Attached Figure Description

[0035] Figure 1 This is a three-dimensional structural schematic diagram of the electrolytic cell of Embodiment 1 of the present invention;

[0036] Figure 2 for Figure 1 3D exploded view of the electrolytic cell;

[0037] Figure 3 for Figure 2 A three-dimensional structural diagram of the intermediate insulating mesh;

[0038] Figure 4 for Figure 1 Longitudinal sectional view of the electrolytic cell;

[0039] Figure 5 for Figure 4 Enlarged view of Part I;

[0040] Figure 6This is a longitudinal sectional view of Embodiment 2 of the electrolytic cell of the present invention from another direction (the dashed arrow indicates the direction of flow channel extension);

[0041] Figure 7 This is a cross-sectional view of Embodiment 2 of the electrolytic cell of the present invention. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0043] Example 1:

[0044] like Figures 1 to 5 The diagram shows a preferred embodiment of the electrolytic cell of the present invention. The electrolytic cell includes a cell body 1, a diaphragm 2, electrode plates 3, and an insulating mesh 4. The electrolytic cell in this embodiment is a single-diaphragm electrolytic cell; however, it can also be designed as a double-diaphragm electrolytic cell or a diaphragmless electrolytic cell as needed.

[0045] The groove 1 is formed by assembling two covers 11 together with fasteners, and a closed inner cavity is formed between the two covers 11; two annular sealing gaskets 12 are arranged sequentially between the two opposite end faces of the two covers 11.

[0046] The diaphragm 2 is a cation exchange membrane, vertically arranged in the inner cavity of the tank 1, with its periphery sandwiched between the two annular sealing gaskets 12. There is one diaphragm 2, which divides the inner cavity of the tank 1 into two electrode chambers 110. The electrode chamber 110 located between the front cover 11 and the diaphragm 2 is designated as cathode chamber 110a, and the electrode chamber 110 located between the rear cover 11 and the diaphragm 2 is designated as anode chamber 110b. Each cover 11 has an inlet 111 and an outlet 112 communicating with the corresponding electrode chamber 110, respectively. Therefore, the water in each electrode chamber 110 flows from bottom to top.

[0047] The electrode plates 3 are arranged in pairs, designated as cathode plate 3a and anode plate 3b. Cathode plate 3a is arranged substantially vertically at the front of cathode chamber 110a, and anode plate 3b is arranged substantially vertically at the rear of anode chamber 110b. Each electrode plate 3 has a conductive post 31 at its top, which passes upward through the corresponding cover 11 and protrudes from the top wall of the cover 11. The conductive posts 31 on cathode plate 3a and anode plate 3b are used for electrical connection to the negative and positive terminals of an external power supply, respectively. In addition, each electrode chamber 110 is provided with at least two mounting seats 13 arranged circumferentially around the electrode plates 3. The mounting seats 13 have slots 131 for inserting the edges of the electrode plates 3, thereby achieving stable positioning of the electrode plates 3.

[0048] There are two insulating meshes 4, which correspond one-to-one with the two electrode chambers 110 mentioned above. They are located in the corresponding electrode chambers 110 and are used to separate the adjacent diaphragms 2 and electrode sheets 3.

[0049] In this embodiment, the insulating mesh 4 is flat and suspended in mid-air, allowing it to move freely under the action of water flow. Specifically, the surface of the insulating mesh 4 has multiple mesh holes 41 for fluid to pass through; the surfaces on both sides of the insulating mesh 4 are formed with tortuous flow channels 40, the inlet of which is close to the liquid inlet 111 and the outlet of which is close to the liquid outlet 112.

[0050] In this embodiment, the insulating mesh 4 is roughly rectangular. The two long sides of the insulating mesh 4 are respectively referred to as the first side and the second side. Multiple guide strips 42 are protruding from the surfaces of both sides of the insulating mesh 4 and are arranged at intervals along the long side of the insulating mesh 4. Each guide strip 42 extends along the short side of the insulating mesh 4 and is basically perpendicular to the line connecting the liquid inlet 111 and the liquid outlet 112. A flow channel unit 420 is formed between two adjacent guide strips 42 and the inner wall of the tank 1. The odd-numbered flow channel unit 420 in the arrangement direction is referred to as the first flow channel unit 420a, and the even-numbered flow channel unit 420 in the arrangement direction is referred to as the second flow channel unit 420b. The first flow channel unit 420a and the second flow channel unit 420b are interconnected near the first side, and the second flow channel unit 420b and the first flow channel unit 420a are interconnected near the second side. All flow channel units 420 together form the flow channel 40. Specifically, the guide strips 42 arranged in the direction of arrangement are designated as the first guide strip 42a, and the even-numbered guide strips 42 arranged in the direction of arrangement are designated as the second guide strip 42b. The end of the second guide strip 42b near the first side has a gap with the inner wall of the tank 1 to form a first notch for connecting the preceding first flow channel unit 420a and the following second flow channel unit 420b. The end of the first guide strip 42a near the second side has a gap with the inner wall of the tank 1 to form a second notch for connecting the preceding second flow channel unit 420b and the following first flow channel unit 420a.

[0051] The aforementioned insulating mesh 4 has the following functions: First, the insulating mesh 4 separates the diaphragm 2 and the electrode plate 3, which can effectively prevent the diaphragm 2 from contacting the electrode plate 3 and causing dry burning; Second, the water flow can form local micro-turbulence as it passes through the mesh 41, and the flow channel 40 extends the water flow path to fully turbulent the flow. The dynamic mesh 4 moves to form dynamic turbulence, which accelerates exhaust, inhibits scale deposition, and accelerates ion transfer; Third, the surface of each guide strip 42 is formed with a scraping surface 421 that can rub against the adjacent diaphragm 2 or electrode plate 3, thereby achieving scraping and descaling.

[0052] In this embodiment, the insulating mesh 4 is made of a food-grade material that is resistant to high and low temperatures, strong acids and alkalis, and has good insulation properties. It is preferably food-grade Teflon. The porosity of the insulating mesh 4 is >1%, preferably 50%, and the thickness of the insulating mesh 4 is >0.1mm, preferably 0.4mm. The shape of the mesh 41 of the insulating mesh 4 is preferably square, and the side length of the square hole is preferably 1mm, so as to maximize the micro-turbulence formed when the water flows through the mesh 41.

[0053] Example 2:

[0054] like Figures 6 to 7 The image shows a second preferred embodiment of the electrolytic cell of the present invention. The difference between this embodiment and Embodiment 1 is that:

[0055] In this embodiment, the insulating mesh 4 is arranged parallel to the diaphragm 2 and the electrode sheet 3, and the electrolytic cell also includes a driving mechanism 5 for driving the insulating mesh 4 to move along its short side.

[0056] There are a pair of drive mechanisms 5, which correspond one-to-one with the electrode chambers 110. Each drive mechanism 5 includes a pull rod 51 and a drive element 52.

[0057] Specifically, the front end of the pull rod 51 is connected to the middle edge of the insulating mesh 4, and the pull rod 51 passes through the corresponding cover 11 from front to back and is exposed on the rear side wall of the cover 11.

[0058] The driving component 52 is an electric push rod, which is installed on the outside of the corresponding cover 11 and has a telescopic rod 521 that can extend and retract in the front and rear direction. The telescopic rod 521 is connected to the rear end of the pull rod 51. In this embodiment, all driving mechanisms 5 share the same driving component 52.

[0059] In this way, activating the drive unit 52 causes the telescopic rod 521 to extend and retract, which in turn moves each insulating mesh 4 in the front-to-back direction via the pull rod 51. This direction of movement is basically perpendicular to the line connecting the liquid inlet 111 and the liquid outlet 112. The drive mechanism 5 serves two purposes: firstly, to achieve dynamic turbulence, and secondly, to adjust the free movement direction and amplitude of the insulating mesh 4, thereby keeping the insulating mesh as centered as possible (the middle of the diaphragm 2 is most likely to be deformed), effectively preventing deformation of the diaphragm 2.

[0060] Taking Example 1 as an example, the working principle of this example is as follows: The electrolyte enters the electrode chamber 110 through the inlet 111. A reduction reaction occurs at the interface between the cathode plate 3a and the solution, and an oxidation reaction occurs at the interface between the anode plate 3b and the solution to produce electrolyzed water. During the electrolysis process, the insulating mesh 4 can move freely under the action of water flow. First, the insulating mesh 4 is separated between the diaphragm 2 and the electrode plate 3, which can effectively prevent the diaphragm 2 from contacting the electrode plate 3 and causing dry burning. Second, the mesh 411 of the insulating mesh 4 forms local micro-turbulence, and the flow channel 40 extends the water flow path to fully turbulent the flow. The movement of the insulating mesh 4 forms dynamic turbulence, which can accelerate exhaust, inhibit scale deposition, and accelerate ion transfer. Third, the scraping surface 421 of the guide strip 42 makes frictional contact with the adjacent diaphragm 2 or electrode plate 3 when it moves freely with the insulating mesh 4, which plays a role in cleaning and scraping scale.

[0061] The advantages of this invention are as follows:

[0062] (1) By adding an insulating mesh 4 between the diaphragm 2 and the electrode 3, the diaphragm 2 is supported and isolated for protection. The insulating mesh 4 is designed as a flat mesh with a flow channel 40. The dynamic turbulence generated by the movement of the insulating mesh 4, the sufficient turbulence achieved by extending the water flow path through the flow channel 40, and the scraping effect formed by the scraping surface 421 contacting the wall surface during movement greatly accelerate the discharge of air bubbles in the electrode 3, diaphragm 2 and electrolytic cell water circuit. Compared with the currently commonly used method of designing an exhaust port on the electrolytic cell, which requires additional sealing design and other auxiliary exhaust design, this accelerated exhaust method has better exhaust effect, simpler structure, and controllable cost, making it very suitable for small electrolytic cells.

[0063] (2) The dynamic turbulence formed by the movement of the insulating mesh 4 and the sufficient turbulence achieved by extending the water flow path of the flow channel 40 prevent scale deposition. The scraping action formed by the contact of the scraping surface 421 with the wall surface further plays a descaling role. Compared with the currently commonly used positive and negative electrode switching descaling method, it does not require the positive and negative electrodes to have a catalytic coating that can participate in the positive electrode reaction and frequent positive and negative electrode switching. It has lower cost, simpler structure, lower requirements for electrical control, and guaranteed electrode life.

[0064] (3) The dynamic turbulence formed by the movement of the insulating mesh 4 and the full turbulence achieved by extending the water flow path of the flow channel 40 accelerate ion diffusion and transfer, thereby improving the pH value and stability of the effluent.

Claims

1. An electrolytic cell, characterized in that: It includes a tank (1) and a diaphragm (2) disposed in the tank (1). The diaphragm (2) divides the inner cavity of the tank (1) into at least two electrode chambers (110). Each electrode chamber (110) is provided with an electrode plate (3) and an insulating mesh (4). The insulating mesh (4) is flat and has a tortuous flow channel (40) formed on its surface. The insulating mesh (4) is separated between two electrode plates (3) and between adjacent diaphragms (2) and electrode plates (3). The insulating mesh (4) is rectangular. The two long sides of the insulating mesh (4) are respectively designated as the first side and the second side. The surface of the insulating mesh (4) is provided with multiple guide strips (42) arranged at intervals along the long side of the insulating mesh (4). Each guide strip (42) extends along the short side of the insulating mesh (4). A flow channel unit (420) is constructed between two adjacent guide strips (42) and the inner wall of the tank (1). The odd-numbered flow channel unit (420) is arranged in the direction of arrangement. The first flow channel unit (420a) is denoted as the first flow channel unit (420a), and the even-numbered flow channel unit (420b) in the arrangement direction is denoted as the second flow channel unit (420b). The first flow channel unit (420a) and the second flow channel unit (420b) are interconnected near the first side, and the second flow channel unit (420b) and the first flow channel unit (420a) are interconnected near the second side. All flow channel units (420) together form the flow channel (40). The surface of the guide strip (42) is formed with a scraping surface (421) that can rub against the adjacent diaphragm (2) or electrode sheet (3); The insulating mesh (4) is suspended in the air so that it can move freely under the action of water flow; or it may also include a drive mechanism (5) for driving the movement of the insulating mesh (4).

2. The electrolytic cell according to claim 1, characterized in that: The guide strip (42) arranged in the direction of arrangement is designated as the first guide strip (42a), and the even-numbered guide strip (42) arranged in the direction of arrangement is designated as the second guide strip (42b). The end of the second guide strip (42b) near the first side has a gap with the inner wall of the tank (1) to form a first notch for connecting the previous first flow channel unit (420a) and the next second flow channel unit (420b). The end of the first guide strip (42a) near the second side has a gap with the inner wall of the tank (1) to form a second notch for connecting the previous second flow channel unit (420b) and the next first flow channel unit (420a).

3. The electrolytic cell according to claim 1, characterized in that: Each electrode chamber (110) has a liquid inlet (111) and a liquid outlet (112) communicating with the electrode chamber (110) in the corresponding tank (1).

4. The electrolytic cell according to claim 3, characterized in that: The extension direction of each of the guide strips (42) is substantially perpendicular to the line connecting the inlet (111) and the outlet (112).

5. The electrolytic cell according to claim 1, characterized in that: The insulating mesh (4) is arranged parallel to the diaphragm (2) and the electrode sheet (3).

6. The electrolytic cell according to claim 5, characterized in that: The drive mechanism (5) includes: A pull rod (51), the first end of which is connected to the edge of the insulating mesh (4); and The drive unit (52) has a telescopic rod (521) that can extend and retract in a direction parallel to the insulating mesh (4), and the telescopic rod (521) is connected to the second end of the pull rod (51).

7. The electrolytic cell according to claim 6, characterized in that: The drive unit (52) is installed on the outside of the groove (1), and the pull rod (51) passes through the groove (1) from the first end to the second end and is exposed on the outer wall of the groove (1).

8. The electrolytic cell according to claim 6, characterized in that: The number of insulating meshes (4) is at least two pieces, and the driving mechanism (5) corresponds one-to-one with the insulating mesh (4). All the driving mechanisms (5) share the same driving component (52).

9. The electrolytic cell according to claim 6, characterized in that: Each electrode chamber (110) has a liquid inlet (111) and a liquid outlet (112) communicating with the electrode chamber (110) in the corresponding tank (1).

10. The electrolytic cell according to claim 9, characterized in that: The extension and retraction direction of the telescopic rod (521) is basically perpendicular to the line connecting the liquid inlet (111) and the liquid outlet (112).

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