Composite braided plate net for electrolytic bath, electrolytic bath, electrolysis device and electrolysis method

Abstract

The invention discloses a composite braided plate net for an electrolytic bath, the electrolytic bath, an electrolysis device and a method, the composite braided plate net is mounted in a cathode chamber and an anode chamber of the electrolytic bath and is used for inducing micro bubbles in a gas-liquid mixture generated by electrolysis to grow up and leading out the micro bubbles; the composite woven plate net comprises hydrophilic silk threads and hydrophobic silk threads, the hydrophilic silk threads and the hydrophobic silk threads are spirally wound to form twisted woven silk threads, the woven silk threads are woven in an omega shape, and a multi-scale gap network structure with omega-shaped pore channels is formed; specifically, the multi-scale gap network structure is a two-dimensional net-shaped stacking structure, the stacking mode is that pore channels in different stacking layers correspond to one another, and flow channels are formed macroscopically. According to the composite woven plate net, coalescence sites can be provided for micro-bubbles on the micro-level, the micro-bubbles are continuously induced to be coalesced and grow up, large bubbles are induced to be rapidly separated through a macroscopic upper flow channel, the bubble accumulation and blockage conditions are reduced, and therefore the gas content is reduced, and the electrolysis efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of alkaline electrolytic water hydrogen production, and particularly relates to a composite woven plate mesh for an electrolytic cell, an electrolytic cell, an electrolytic device, and a method. Background Art

[0002] In recent years, the explosive growth of global energy demand has led to the massive consumption of fossil fuels, causing serious environmental pollution and the greenhouse effect. As a zero-carbon energy carrier, hydrogen energy not only has a very high energy density but also can achieve large-scale long-term energy storage, making it an important carrier for the green and low-carbon transformation of energy.

[0003] Among all current electrolytic water hydrogen production methods, alkaline electrolytic water hydrogen production has become the most widely used method for industrial electrolytic water hydrogen production due to its low equipment cost and mature process. However, at present, the further development of alkaline electrolytic water hydrogen production is restricted by its excessive power consumption.

[0004] This is mainly because additional voltage consumption occurs during the electrolysis of water. Specifically, during the electrolysis process, especially at high current densities, a large number of small bubbles are generated. These small bubbles will cause ohmic voltage drop, increasing the energy consumption and risk of equipment operation. The change in conductivity in the electrolytic cell affected by bubbles and the reduction of the effective reaction area on the electrode surface are important reasons affecting the electrolysis efficiency. Therefore, it is of great significance to study how to reduce the impact of bubbles on the electrolysis efficiency.

[0005] To address this problem, CN117165978A discloses an electrolytic cell, an electrolytic device, and a method for regulating bubbles using a porous structure. The electrolytic cell installs a porous coalescence internal component in the electrolysis chamber to increase liquid turbulence, increase the collision probability of fine bubbles, and at the same time provide coalescence sites for the fine bubbles to induce their coalescence and growth. The porous coalescence internal component adopts a three-dimensional porous foam structure or a two-dimensional network stacking structure, and its material is a hydrophobic material or has a hydrophobic coating on the surface.

[0006] Although the porous coalescence internal component in this device can induce fine bubbles to stay and coalesce to form large bubbles, affected by its weaving method, the bubble detachment is irregular, the detachment speed is slow, and it is easy to cause blockage, resulting in an excessive residence time of bubbles in the electrolytic cell. In addition, the material of the porous coalescence internal component is single, easy to be corroded by alkaline solution, and the overall structure is relatively soft and unable to play a supporting role. Summary of the Invention

[0007] The purpose of the present invention is to propose a composite woven plate mesh for an electrolytic cell, an electrolytic cell, an electrolytic device, and a method for the above problems in the prior art.

[0008] To achieve the above purpose, the technical solutions adopted by the present invention are as follows:

[0009] In the first aspect of the present invention, there is provided a composite woven plate mesh for an electrolytic cell. The composite woven plate mesh is installed in the cathode chamber and the anode chamber of the electrolytic cell and is used to induce the growth of fine bubbles in the gas-liquid mixture generated by electrolysis and discharge them. The composite woven plate mesh includes hydrophilic filaments and hydrophobic filaments, wherein:

[0010] The hydrophilic filaments and the hydrophobic filaments are helically wound to form a "twisted" woven filament. The woven filament is woven in an Ω shape to form a multi-scale void network structure with Ω-shaped channels. Specifically, the multi-scale void network structure is a two-dimensional network stacking structure, and the stacking method is that the channels in different stacking layers correspond to each other, forming a flow channel macroscopically.

[0011] In the woven filament, the volume ratio of the hydrophilic filament to the hydrophobic filament is 3:1 to 5:1, and the angle θ between the stacking layer and the electrolyte flow direction is set to 25° 75°; the porosity of the composite woven plate mesh is 89% to 98%.

[0012] Further, the material of the hydrophilic filament is selected from one or more of platinum, nickel, indium tin oxide, ruthenium oxide, and graphene;

[0013] The material of the hydrophobic filament is selected from one or more of polyurethane, polyolefin, polycarbonate, polyamide, polyacrylonitrile, polyester, PTFE, FEP, ETFE, and PFA.

[0014] Further, in the woven filament, the spacing between the hydrophilic filament or the hydrophobic filament is 0.08 to 1.2 mm; the diameter of the hydrophilic filament or the hydrophobic filament is 80 to 180 , and the weaving density is 50 to 150 mesh.

[0015] Further, there is one or more composite woven plate meshes in the cathode chamber or the anode chamber;

[0016] If there is one composite woven plate mesh, it is installed in the upper middle part of the cathode chamber or the anode chamber;

[0017] If there are multiple composite woven plate meshes, they are arranged in a stepped manner along the electrolyte flow direction from the smallest porosity to the largest.

[0018] Further, when there are two composite woven plate meshes, they are arranged in sequence along the electrolyte flow direction with porosities of 91% - 94% and 95% - 98% respectively;

[0019] When there are three composite woven plate meshes, they are arranged in sequence along the electrolyte flow direction with porosities of 89% - 91%, 91% - 94%, and 95% - 98% respectively.

[0020] The second aspect of the present invention lies in providing an electrolytic cell, which comprises a plurality of electrolytic compartments connected in parallel. A single electrolytic compartment includes a cathode plate and an anode plate arranged oppositely, a diaphragm located between the two plates, and a cathode electrode and an anode electrode attached to both sides of the diaphragm. A cathode chamber is formed between the cathode plate and the cathode electrode, and an anode chamber is formed between the anode plate and the anode electrode;

[0021] The lower end of the electrolytic cell is provided with an electrolytic cell inlet communicating with the cathode chamber and the anode chamber, and its upper end is provided with an electrolytic cell outlet, including a first outlet communicating with the cathode chamber and a second outlet communicating with the anode chamber;

[0022] The above-mentioned composite woven plate mesh is installed in the cathode chamber and the anode chamber.

[0023] Furthermore, the composite woven plate mesh is subjected to surface roughening treatment to increase the surface roughness, but the outer surface edge is not roughened to avoid piercing the diaphragm.

[0024] The third aspect of the present invention lies in providing an electrolysis device, which comprises the above-mentioned electrolytic cell, as well as two gas-liquid separators, two gas treatment devices, an alkali liquid mixer and two alkali liquid circulation pumps, wherein:

[0025] The mixed liquid inlets of the two gas-liquid separators are respectively communicated with the first outlet and the second outlet of the electrolytic cell; their liquid phase outlets are communicated with the alkali liquid mixer through the corresponding alkali liquid circulation pumps, and the alkali liquid mixer is communicated with the electrolytic cell inlet of the electrolytic cell to realize the circulation of the electrolyte; their gas phase outlets are communicated with the corresponding gas treatment devices.

[0026] The fourth aspect of the present invention lies in providing an electrolysis method, which uses the above-mentioned electrolysis device. The electrolysis method comprises the following steps:

[0027] The electrolyte enters the electrolytic compartment from the electrolytic cell inlet at the bottom of the electrolytic cell, flows from bottom to top, and after electrolysis, becomes a gas-liquid mixture containing a large number of fine bubbles; the fine bubbles pass through the composite woven plate mesh during the rising process. Due to the low wettability of the hydrophobic filaments in the composite woven plate mesh, coalescence sites will be provided for the fine bubbles at the microscopic level, continuously inducing the coalescence and growth of the fine bubbles; and the flow channel structure formed by the composite woven plate mesh at the macroscopic level will induce the rapid detachment of larger bubbles, reducing the accumulation and blockage of bubbles;

[0028] The coalesced and separated large bubbles enter the gas-liquid separator together with the electrolyte. After gas-liquid separation, the electrolyte returns to the electrolytic cell for recycling, and the gas enters the gas treatment device for drying and pressurization treatment. The treated gas can be stored and used.

[0029] Furthermore, the flow rate of the electrolyte in the electrolytic cell is 0.03 - 0.06 m / s, and the current density is 250 - 652 A / m²; under normal pressure, the operating temperature of the electrolytic cell is 65 - 85 °C.

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) The present invention utilizes a composite woven plate mesh woven from hydrophilic and hydrophobic materials, which has a porous structure, strengthens the liquid turbulence in the flow channel, increases the collision probability of microbubbles, and the composite woven plate mesh is woven in an Ω shape, forming a flow channel structure at the macroscopic level, inducing large bubbles to quickly detach, reducing the situation of bubble accumulation and blockage; due to the low wettability of the hydrophobic material, at the microscopic level, it will provide coalescence sites for microbubbles, continuously induce the coalescence and growth of microbubbles, and make them quickly detach from the flow channel, thereby reducing the gas holdup, solving the problem that the gas bubble group increases the voltage of the electrolytic cell, and improving the electrolysis efficiency.

[0032] (2) The composite woven plate mesh designed in the present invention is woven from two materials, reducing the probability of being corroded and enhancing the stability of the system operation.

[0033] (3) The composite woven plate mesh designed in the present invention can not only be applied in small electrolytic cells, but also in large industrial equipment, and has great potential in industrial applications. Description of the Drawings

[0034] Figure 1 is a schematic structural diagram of an electrolytic cell using a composite woven plate mesh to coalesce and separate bubbles.

[0035] Figure 2 is a schematic structural diagram of an electrolytic cell compartment.

[0036] Figure 3 is a schematic structural diagram of the Ω weaving process.

[0037] Figure 4 is a three-dimensional structural diagram of the composite woven plate mesh.

[0038] Figure 5 is a schematic diagram of gas-liquid flow in a partial electrolytic cell compartment.

[0039] Figure 6 is Figure 5 a partial enlarged view of the composite woven plate mesh coalescing and separating bubbles in the electrolytic cell compartment in

[0040] Figure 7 is a schematic structural diagram of an electrolysis device using a composite woven plate mesh to coalesce and separate bubbles.

[0041] Figure 8 is a comparison chart of the gas holdup during electrolysis of the electrolysis devices in Example 3 and Comparative Example 6.

[0042] Figure 9 It is a comparison chart of the energy consumption during electrolysis of the electrolysis devices in Example 3 and Comparative Example 6.

[0043] In the figure: 10 - electrolytic cell; 11 - cathode plate; 12 - anode plate; 13 - diaphragm; 14 - cathode electrode; 15 - anode electrode; 16 - electrolytic cell inlet; 17 - first outlet; 18 - second outlet; 19 - composite woven plate mesh; 20 - gas - liquid separator; 30 - gas treatment equipment; 40 - lye mixer; 50 - lye circulation pump; In the composite woven plate mesh, the black lines represent hydrophobic silk threads, and the blue lines represent hydrophilic silk threads. Detailed implementation manners

[0044] The technical solutions of the invention will be clearly and elaborately described below with reference to the accompanying drawings through specific embodiments. It should be understood that the following embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by those of ordinary skill in the art without creative efforts all fall within the protection scope of the present invention. Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art.

[0045] Example 1: An electrolytic cell for coalescing and separating bubbles using a composite woven plate mesh

[0046] As Figure 1 and Figure 2 shown, the electrolytic cell 10 includes a plurality of parallel - connected electrolytic compartments. A single electrolytic compartment includes a cathode plate 11 and an anode plate 12 arranged oppositely, a diaphragm 13 located between the two plates, and cathode and anode electrodes 14 and 15 attached to both sides of the diaphragm 13. A cathode chamber is formed between the cathode plate 11 and the cathode electrode 14, and an anode chamber is formed between the anode plate 12 and the anode electrode 15; the diaphragm 13 is used to prevent the electrolysis products in the cathode and anode regions from directly contacting and reduce the occurrence of side reactions;

[0047] The lower end of the electrolytic cell 10 is provided with an electrolytic cell inlet 16 communicating with the cathode chamber and the anode chamber, and its upper end is provided with an electrolytic cell outlet, including a first outlet 17 communicating with the cathode chamber and a second outlet 18 communicating with the anode chamber, for respectively outputting the gas - containing electrolyte in the cathode chamber and the anode chamber; the electrolyte enters from the bottom of the electrolytic cell 10, flows from bottom to top, and the gas - containing electrolyte generated after electrolysis is discharged from the electrolytic cell outlet.

[0048] Composite woven plate meshes 19 are installed in both the cathode chamber and the anode chamber for inducing the growth of fine bubbles in the gas - liquid mixture generated by electrolysis and discharging them; the composite woven plate mesh 19 includes hydrophilic silk threads and hydrophobic silk threads, where:

[0049] As Figure 3 and Figure 4 shown, the hydrophilic filaments and hydrophobic filaments are helically wound to form a "twisted" braided filament. The braided filament is braided in an Ω shape to form a multi-scale void network structure with Ω-shaped channels. Specifically, the multi-scale void network structure adopts a two-dimensional network stacking structure, and the stacking method is that the channels in different stacking layers correspond to each other, and a flow channel is formed macroscopically.

[0050] In the composite braided plate mesh 19, the volume ratio of the hydrophilic filaments to the hydrophobic filaments is 3:1 to 5:1. As Figure 6 shown, the angle θ between the stacking layer and the electrolyte flow direction is set to 25° 75°; the porosity of the composite braided plate mesh 19 is 89% to 98%.

[0051] As Figure 5 and Figure 6 shown, when the gas-containing electrolyte generated by electrolysis passes through the composite braided plate mesh 19, its porous structure will strengthen the liquid turbulence and increase the collision probability of microbubbles. Due to the low wettability of the hydrophobic filaments, microscopically, it provides coalescence sites for microbubbles and continuously induces the coalescence and growth of microbubbles; at the same time, the flow channel structure formed macroscopically induces larger bubbles to quickly detach, reducing the accumulation and blockage of bubbles.

[0052] In addition, the composite braided plate mesh 19 installed between the electrodes and the electrode plates can also play a role in supporting the electrodes, and the composite braided structure is not easily corroded in alkaline electrolytes.

[0053] The material of the above-mentioned hydrophilic filaments is selected from one or more of platinum, nickel, indium tin oxide, ruthenium oxide, and graphene;

[0054] The material of the above-mentioned hydrophobic filaments is selected from one or more of polyurethane, polyolefin, polycarbonate, polyamide, polyacrylonitrile, polyester, PTFE, FEP, ETFE, and PFA.

[0055] In the braided filaments, the spacing between the hydrophilic filaments or the hydrophobic filaments is 0.08 to 1.2 mm; the diameter of the hydrophilic filaments or the hydrophobic filaments is 80 to 180 , and the braiding density is 50 to 150 meshes.

[0056] Preferably, the electrolytic cell 10 is a cylindrical structure with a diameter of 1000 mm and a height of 2000 mm.

[0057] In specific applications, one or more composite braided plate meshes 19 can be installed in the cathode chamber and the anode chamber;

[0058] If there is one composite woven plate mesh 19, it is installed in the upper middle part of the cathode chamber or the anode chamber, preferably at a position 300 - 500 mm away from the electrolytic cell outlet.

[0059] If there are multiple composite woven plate meshes 19, they are arranged in a stepped manner along the electrolyte flow direction from the smallest porosity to the largest. Specifically:

[0060] When there are two composite woven plate meshes 19, they are arranged in sequence along the electrolyte flow direction with porosities of 91% - 94% and 95% - 98% respectively;

[0061] When there are three composite woven plate meshes 19, they are arranged in sequence along the electrolyte flow direction with porosities of 89% - 91%, 91% - 94%, and 95% - 98% respectively.

[0062] When the gas - liquid mixture passes through the composite woven plate meshes 19 with different porosities arranged in a stepped manner from bottom to top, since the porosity of the lower composite woven plate mesh 19 is smaller, it can better intercept small bubbles and make them coalesce. The bubbles move and coalesce and grow along the flow channel under the action of the liquid - phase drag force; while the porosity of the upper composite woven plate mesh 19 is larger, it can enable the large bubbles formed by coalescence to quickly break away without causing blockage of the pore channels.

[0063] In addition, the composite woven plate mesh 19 is subjected to surface roughening treatment to increase the surface roughness, but the outer surface edge is not roughened to avoid piercing the diaphragm 13.

[0064] Example 2: An electrolytic device for coalescing and separating bubbles using a composite woven plate mesh

[0065] As Figure 7 shown, the electrolytic device of this example includes the electrolytic cell 10 of the above - mentioned Example 1, two gas - liquid separators 20, two gas treatment devices 30, an alkali liquor mixer 40, and two alkali liquor circulation pumps 50, where:

[0066] The mixed - liquid inlets of the two gas - liquid separators 20 are respectively connected to the first outlet 17 and the second outlet 18 of the electrolytic cell 10; their liquid - phase outlets are connected to the alkali liquor mixer 40 through the corresponding alkali liquor circulation pumps 50, and the alkali liquor mixer 40 is connected to the electrolytic cell inlet 16 of the electrolytic cell 10 to realize the circulation of the electrolyte; their gas - phase outlets are connected to the corresponding gas treatment devices 30.

[0067] The gas treatment device 30 is used to receive hydrogen or oxygen from the gas - liquid separator 20, and perform drying and pressurization treatment on it for subsequent data analysis.

[0068] It should be noted that the above-mentioned gas-liquid separator 20, gas treatment device 30, lye mixer 40 and lye circulation pump 50 are all conventional devices in the art and can be selected according to actual needs. Their specific structures will not be elaborated here.

[0069] The electrolysis method and principle of the electrolysis device using the composite woven mesh to coalesce and separate bubbles are as follows:

[0070] The electrolyte enters the electrolysis cell from the electrolysis cell inlet 16 at the bottom of the electrolysis cell 10 and flows upward. After electrolysis, it becomes a gas-liquid mixture containing a large number of fine bubbles. During the upward movement of the fine bubbles, they pass through the composite woven mesh 19. Since the hydrophobic filaments in the composite woven mesh 19 have the characteristic of low wettability, at the microscopic level, they will provide coalescence sites for the fine bubbles and continuously induce the coalescence and growth of the fine bubbles. And the flow channel structure formed by the composite woven mesh 19 at the macroscopic level will induce the rapid detachment of large bubbles, reducing the accumulation and blockage of bubbles.

[0071] Under the action of the lye circulation pump 50, the coalesced and separated large bubbles enter the gas-liquid separator 20 together with the electrolyte for gas-liquid separation. After separation, the gas phase enters the gas treatment device 30 from the top of the gas-liquid separator 20 for drying and pressurization treatment. The treated gas can be stored and used. The separated electrolyte is discharged from the bottom of the gas-liquid separator 20 and is transported through a pipeline to the lye mixer 40 to supply liquid to the electrolysis cell 10, realizing the circulation of the electrolyte.

[0072] During electrolysis, the flow rate of the electrolyte in the electrolysis cell 10 is 0.03 - 0.06 m / s, the current density is 250 - 652 A / m², and the operating temperature of the electrolysis cell 10 is 65 - 85 °C (under normal pressure).

[0073] The volume of the electrolyte in the gas-liquid separator 20 is controlled within 1 / 2 - 3 / 4 of the volume of the gas-liquid separator 20; the outlet pressure of the lye circulation pump 50 is 0.8 - 1.6 Mpa.

[0074] Example 3

[0075] Using the electrolysis device of Example 2 above to electrolyze the electrolyte of 30 wt% potassium hydroxide solution to generate hydrogen and oxygen, the volume flow rate of the electrolyte at the inlet is set to 1200 mL / min, the flow rate of the electrolyte is 0.035 m / s, the current density is 312.5 A / m², and the operating temperature of the electrolysis cell is 65 °C;

[0076] Three-stage composite woven meshes are respectively arranged in the cathode chamber and the anode chamber, where:

[0077] The material of the hydrophilic filaments is nickel; the material of the hydrophobic filaments is polyurethane.

[0078] The spacing between each silk thread is 0.5 mm. The diameters of both the hydrophilic silk thread and the hydrophobic silk thread are 120 μm, and the weaving density is 80 mesh. The volume ratio of the hydrophilic silk thread to the hydrophobic silk thread is 3:1. The porosity of the three-stage composite woven plate mesh is 90%, 93%, and 95% from bottom to top respectively.

[0079] The angle θ between the stacked layer in the composite woven plate mesh and the electrolyte flow direction is 60°.

[0080] Example 4

[0081] The electrolysis device and electrolysis conditions in this example are basically the same as those in Example 3, except that in the composite woven plate mesh, the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread is 4:1.

[0082] Example 5

[0083] The electrolysis device and electrolysis conditions in this example are basically the same as those in Example 3, except that in the composite woven plate mesh, the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread is 5:1.

[0084] Example 6

[0085] The electrolysis device and electrolysis conditions in this example are basically the same as those in Example 3, except that a composite woven plate mesh is respectively arranged in the cathode chamber and the anode chamber, and the porosity of this composite woven plate mesh is 95%.

[0086] Comparative Example 1

[0087] The electrolysis device and electrolysis conditions in this comparative example are basically the same as those in Example 3, except that the composite woven plate mesh is not used.

[0088] Comparative Example 2

[0089] The electrolysis device and electrolysis conditions in this comparative example are basically the same as those in Example 3, except that the composite woven plate mesh is replaced with the porous structure in invention application CN117165978A.

[0090] Comparative Example 3

[0091] The electrolysis device and electrolysis conditions in this comparative example are basically the same as those in Example 3, except that in the composite woven plate mesh, the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread is 2:1.

[0092] Comparative Example 4

[0093] The electrolysis device and electrolysis conditions in this comparative example are basically the same as those in Example 3, except that in the composite woven plate mesh, the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread is 1:1.

[0094] Comparative Example 5

[0095] This comparative example is basically the same as the electrolysis device and electrolysis conditions of Example 3, except that the composite woven plate mesh is only composed of hydrophobic silk threads.

[0096] Comparative Example 6

[0097] This comparative example and the electrolysis device and electrolysis conditions of Example 3 are basically the same, except that the composite woven plate mesh is made by cross-weaving the woven silk threads.

[0098] The bubble size and gas holdup in the electrolyte at the top of the electrolytic cell after electrolysis in the above Examples 3 - 6 and Comparative Examples 1 - 5 are shown in Table 1 below. The gas holdup and energy consumption of the electrolysis devices in Example 3 and Comparative Example 6 at different superficial velocities are compared as Figure 8 and Figure 9 shown.

[0099] Table 1

[0100]

[0101] It can be seen from the results in Table 1 that using the composite woven plate mesh of the present invention can significantly increase the bubble size in the electrolyte to millimeter level, and the bubble detachment speed is relatively fast, which can effectively reduce the voltage of the electrolysis cell, thereby improving the electrolysis efficiency; in Comparative Example 1, the composite woven plate mesh structure was not used, resulting in a small bubble group and a high gas holdup. In Comparative Example 2, the porous structure in CN117165978A was used. Since there is no flow channel, the bubble detachment is irregular and blocked, and the bubble detachment speed is slow, resulting in a gas holdup higher than that of Example 3 with a flow channel. As Figure 8 and Figure 9 can be seen, although Comparative Example 6 also uses woven silk threads, no flow channel is formed, and the gas holdup and energy consumption are much higher than those of Example 3.

[0102] In addition, the volume ratio of hydrophilic silk threads to hydrophobic silk threads also affects the gas holdup. Examples 3 - 5 and Comparative Examples 3 - 5 use different volume ratios of hydrophilic silk threads to hydrophobic silk threads. Hydrophobic silk threads contribute to the coalescence of bubbles to form larger bubbles, while an appropriate amount of hydrophilic silk threads helps the large bubbles formed by coalescence to quickly detach along the flow channel. When the volume ratio of hydrophilic silk threads to hydrophobic silk threads is too small, it will increase the bubble accumulation, reduce the bubble detachment efficiency, resulting in an extended residence time of bubbles in the electrolytic cell and an increase in gas holdup. When the ratio of the two is too large, it will lead to fewer attachment sites for small bubbles, reducing the probability of bubble coalescence in the electrolyte and making the overall bubble size smaller. Therefore, the volume ratio of hydrophilic silk threads to hydrophobic silk threads is preferably 3:1 - 5:1.

[0103] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A composite woven plate mesh for an electrolytic cell, characterized in that, The composite woven plate mesh is installed in the cathode chamber and the anode chamber of the electrolytic cell, and is used to induce the growth of fine bubbles in the gas-liquid mixture generated by electrolysis and export them; the composite woven plate mesh includes hydrophilic filaments and hydrophobic filaments, where: The hydrophilic filaments and the hydrophobic filaments are helically wound to form a "twisted" woven filament, and the woven filament is woven in an Ω shape to form a multi-scale void network structure with Ω-shaped channels; specifically, the multi-scale void network structure is a two-dimensional network stacking structure, and the stacking method is that the channels in different stacking layers correspond to each other, and a flow channel is formed macroscopically. In the composite woven plate mesh, the volume ratio of the hydrophilic filaments to the hydrophobic filaments is 3:1 to 5:1, and the angle θ between the stacking layer and the electrolyte flow direction is set to 25° < θ < 75°; the porosity of the composite woven plate mesh is 89% to 98%.

2. The composite woven plate mesh for an electrolytic cell according to claim 1, characterized in that, The material of the hydrophilic filaments is selected from one or more of platinum, nickel, indium tin oxide, ruthenium oxide, and graphene. The material of the hydrophobic filaments is selected from one or more of polyurethane, polyolefin, polycarbonate, polyamide, polyacrylonitrile, polyester, PTFE, FEP, ETFE, and PFA.

3. The composite woven plate mesh for an electrolytic cell according to claim 1, characterized in that, In the woven filament, the spacing between the hydrophilic filaments or the hydrophobic filaments is 0.08 to 1.2 mm; the diameter of the hydrophilic filaments or the hydrophobic filaments is 80 to 180 μm, and the weaving density is 50 to 150 meshes.

4. The composite woven plate mesh for an electrolytic cell according to claim 1, characterized in that, There is one or more composite woven plate meshes in the cathode chamber or the anode chamber. If there is one composite woven plate mesh, it is installed in the upper middle part of the cathode chamber or the anode chamber. If there are multiple composite woven plate meshes, they are arranged in a stepped manner along the electrolyte flow direction from the smallest porosity to the largest.

5. The composite woven plate mesh for an electrolytic cell according to claim 4, characterized in that, When there are two composite woven plate meshes, they are arranged in sequence along the electrolyte flow direction with porosities of 91% - 94% and 95% - 98% respectively. When there are three composite woven plate meshes, they are arranged in sequence along the electrolyte flow direction with porosities of 89% - 91%, 91% - 94%, and 95% - 98% respectively.

6. An electrolytic cell, characterized in that, The electrolytic cell includes a plurality of parallel electrolytic compartments. A single electrolytic compartment includes a cathode plate and an anode plate arranged opposite to each other, a diaphragm located between the two plates, and a cathode electrode and an anode electrode attached to both sides of the diaphragm. A cathode chamber is formed between the cathode plate and the cathode electrode, and an anode chamber is formed between the anode plate and the anode electrode. The lower end of the electrolytic cell is provided with an electrolytic cell inlet communicating with the cathode chamber and the anode chamber, and its upper end is provided with an electrolytic cell outlet, including a first outlet communicating with the cathode chamber and a second outlet communicating with the anode chamber. The composite woven plate mesh described in any one of claims 1 to 5 is installed in the cathode chamber and the anode chamber.

7. The electrolytic cell according to claim 6, characterized in that, The composite woven plate mesh is subjected to surface roughening treatment to increase the surface roughness, but the outer surface edge is not roughened to avoid piercing the diaphragm.

8. An electrolysis device, characterized in that, The electrolysis device includes the electrolytic cell described in claim 5, as well as two gas-liquid separators, two gas treatment devices, an alkali liquid mixer, and two alkali liquid circulation pumps, where: The mixed liquid inlets of the two gas-liquid separators are respectively communicated with the first outlet and the second outlet of the electrolytic cell; its liquid phase outlet is communicated with the lye mixer through the corresponding lye circulation pump, and the lye mixer is communicated with the electrolytic cell inlet of the electrolytic cell to realize the circulation of the electrolytic solution; its gas phase outlet is communicated with the corresponding gas treatment equipment.

9. An electrolysis method, using the electrolysis device according to claim 8, characterized in that, The electrolysis method includes the following steps: The electrolytic solution enters the electrolytic compartment at the bottom of the electrolytic cell from the electrolytic cell inlet, flows from bottom to top, and after electrolysis, it becomes a gas-liquid mixture containing a large number of fine bubbles; the fine bubbles pass through the composite woven plate mesh during the rising process. Due to the low wettability of the hydrophobic filaments in the composite woven plate mesh, coalescence sites will be provided for the fine bubbles at the microscopic level, continuously inducing the coalescence and growth of the fine bubbles; and the flow channel structure formed by the composite woven plate mesh at the macroscopic level will induce the rapid detachment of larger bubbles, reducing the accumulation and blockage of bubbles. The coalesced and separated large bubbles enter the gas-liquid separator together with the electrolytic solution. After gas-liquid separation, the electrolytic solution returns to the electrolytic cell for recycling, and the gas enters the gas treatment equipment for drying and pressurization treatment, and the treated gas can be stored and used.

10. The electrolysis method according to claim 9, characterized in that, The flow rate of the electrolytic solution in the electrolytic cell is 0.03~0.06 m / s, and the current density is 250~652 A / m²; under normal pressure, the operating temperature of the electrolytic cell is 65~85 °C.

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