Composite woven plate mesh for electrolytic cell, electrolytic cell, electrolytic device and method

Abstract

The present invention discloses a composite woven plate mesh for an electrolytic cell, an electrolytic cell, an electrolysis device, and a method. 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 guide them out. The composite woven plate mesh includes hydrophilic silk threads and hydrophobic silk threads, wherein: the hydrophilic silk threads and the hydrophobic silk threads are spirally twisted to form a "twisted" woven silk thread, and the woven silk thread adopts an Ω-shaped weave to form a multi-scale void network structure with Ω-shaped pores. Specifically, the multi-scale void network structure is a two-dimensional mesh stacking structure, and the stacking method is that the pores in different stacking layers correspond to each other, forming a flow channel on a macro scale. The composite woven plate mesh provides agglomeration sites for fine bubbles at the micro level, continuously inducing the fine bubbles to coalesce and grow. On a macro level, the flow channel induces larger bubbles to quickly detach, reducing bubble accumulation and blockage, thereby reducing gas holdup and improving electrolysis efficiency.

Description

Technical Field

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

[0002] In recent years, the explosive growth in global energy demand has led to a surge in fossil fuel consumption, severe environmental pollution, and the greenhouse effect. Hydrogen, as a zero-carbon energy carrier, not only has a very high energy density but also enables large-scale, long-term energy storage, making it a key enabler of the green, low-carbon energy transition.

[0003] Among all the current methods of hydrogen production by water electrolysis, alkaline water electrolysis has become the most widely used method for industrial hydrogen production due to its low equipment cost and mature process. However, the further development of alkaline water electrolysis is currently restricted by its excessively high electricity consumption.

[0004] This is primarily due to the additional voltage consumption generated during water electrolysis. Specifically, during electrolysis, especially at high current densities, a large number of small bubbles are generated. These bubbles create an ohmic drop, increasing equipment operating energy consumption and risks. The resulting changes in conductivity within the electrolytic cell and the reduction in the effective reaction area on the electrode surface are significant factors affecting electrolysis efficiency. Therefore, research on how to reduce the impact of bubbles on electrolysis efficiency is of great significance.

[0005] To address this issue, CN117165978A discloses an electrolytic cell, electrolysis device, and method for controlling bubbles using a porous structure. The electrolytic cell incorporates a porous coalescing internal component within the electrolysis chamber, increasing liquid turbulence and the probability of collisions between tiny bubbles. This internal component provides coalescing sites for the bubbles, inducing their aggregation and growth. The porous coalescing internal component utilizes a three-dimensional porous foam structure or a two-dimensional reticular stacked structure, and is made of a hydrophobic material or has a hydrophobic coating.

[0006] While the porous coalescing internals in this device can induce tiny bubbles to settle and coalesce into larger bubbles, their weaving pattern results in irregular and slow bubble detachment, which can easily cause blockages and result in bubbles remaining in the electrolytic cell for extended periods of time. Furthermore, the porous coalescing internals are made of a single material, easily corroded by alkaline solutions, and their overall structure is relatively soft, rendering them incapable of providing support. Summary of the Invention

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

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

[0009] A first aspect of the present invention is to provide a composite woven plate mesh for an electrolytic cell, the composite woven plate mesh being installed in the cathode chamber and the anode chamber of the electrolytic cell and being used to induce the growth and discharge of fine bubbles in the gas-liquid mixture generated by electrolysis; the composite woven plate mesh comprises hydrophilic silk threads and hydrophobic silk threads, wherein:

[0010] Hydrophilic silk threads and hydrophobic silk threads are spirally twisted to form a "twisted" woven silk thread. The woven silk thread adopts an Ω-shaped weaving to form a multi-scale void network structure with Ω-shaped channels; specifically, the multi-scale void network structure is a two-dimensional mesh stacking structure, and the stacking method is that the channels in different stacking layers correspond to each other, forming a flow channel on a macro scale.

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

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

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

[0014] Furthermore, in the braided silk thread, the spacing between the hydrophilic silk thread or the hydrophobic silk thread is 0.08~1.2mm; the diameter of the hydrophilic silk thread or the hydrophobic silk thread is 80~180 , the weaving density is 50~150 mesh.

[0015] Furthermore, there are 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 middle and upper part of the cathode chamber or the anode chamber;

[0017] If there are multiple composite woven plate meshes, they are arranged in steps from small to large porosity along the flow direction of the electrolyte.

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

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

[0020] A second aspect of the present invention provides an electrolytic cell comprising a plurality of parallel electrolytic cells, each of which comprises a cathode plate and an anode plate disposed opposite each other, a diaphragm between the plates, and a cathode electrode and an anode electrode disposed on opposite sides of the diaphragm, wherein 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 the 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 cathode chamber and the anode chamber are equipped with the composite woven plate mesh.

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

[0024] A third aspect of the present invention is to provide an electrolysis device, comprising the above-mentioned electrolytic cell, 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 connected to the first outlet and the second outlet of the electrolytic cell; their liquid phase outlets are connected to the alkali liquid mixer via the corresponding alkali liquid circulation pump, and the alkali liquid mixer is connected to the electrolytic cell inlet of the electrolytic cell to realize the circulation of the electrolyte; their gas phase outlets are connected to the corresponding gas processing equipment.

[0026] A fourth aspect of the present invention is to provide an electrolysis method, using the above-mentioned electrolysis device, the electrolysis method comprising the following steps:

[0027] The electrolyte enters the electrolysis chamber 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 tiny bubbles. During the upward process, the tiny bubbles pass through the composite woven plate mesh. Because the hydrophobic silk threads in the composite woven plate mesh have the characteristic of low wettability, they provide coalescence sites for the tiny bubbles at the micro level, continuously inducing the tiny bubbles to gather and grow. The flow channel structure formed at the macro level of the composite woven plate mesh will induce larger bubbles to detach quickly, reducing bubble accumulation and blockage.

[0028] The large bubbles that are gathered and separated 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 equipment 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 0.03~0.06m / s, the current density is 250~652A / m²; under normal pressure, the operating temperature of the electrolytic cell is 65~85℃.

[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 turbulence of the liquid in the flow channel, increases the collision probability of micro bubbles, and is woven in an Ω shape. The composite woven plate mesh forms a flow channel structure at the macro level, inducing large bubbles to quickly detach, reducing bubble accumulation and blockage; since the hydrophobic material has the characteristic of low wettability, it provides agglomeration sites for micro bubbles at the micro level, continuously inducing micro bubbles to aggregate and grow, causing them to quickly detach from the flow channel, thereby reducing the gas content, solving the problem of bubble groups causing the voltage of the electrolysis chamber to increase, and improving the electrolysis efficiency.

[0032] (2) The composite woven plate mesh designed in the present invention is woven from two materials, which reduces the probability of corrosion and improves the stability of system operation.

[0033] (3) The composite woven plate mesh designed by the present invention can be used not only in small electrolytic cells but also in large industrial equipment, and has great potential in industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the structure of an electrolytic cell that utilizes a composite woven plate mesh to gather and separate bubbles.

[0035] Figure 2 It is a structural diagram of the electrolysis chamber.

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

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

[0038] Figure 5 This is a schematic diagram of the gas-liquid flow in the local electrolysis chamber.

[0039] Figure 6 yes Figure 5 A partial enlarged view of the composite woven plate mesh gathering and separating bubbles in the electrolysis chamber.

[0040] Figure 7 It is a schematic diagram of the structure of an electrolysis device that uses a composite woven plate mesh to gather and separate bubbles.

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

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

[0043] In the picture:

[0044] 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;

[0045] 20-gas-liquid separator; 30-gas processing equipment; 40-alkali solution mixer; 50-alkali solution circulation pump;

[0046] In the composite woven mesh, black lines represent hydrophobic threads and blue lines represent hydrophilic threads. DETAILED DESCRIPTION

[0047] The following is a clear and detailed description of the technical solutions of the invention through specific embodiments in conjunction with the accompanying drawings. It should be understood that the following embodiments are only 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 ordinary technicians in this field without making creative work are all within the scope of protection of the present invention. Unless otherwise defined, all professional and scientific terms used in this article have the same meaning as those familiar to those skilled in the art.

[0048] Example 1: An electrolytic cell utilizing a composite woven plate to gather and separate bubbles

[0049] like Figure 1 and Figure 2 As shown, the electrolytic cell 10 includes a plurality of parallel electrolytic chambers. A single electrolytic chamber includes a cathode plate 11 and an anode plate 12 disposed opposite each other, a diaphragm 13 located between the two plates, and a cathode electrode 14 and an anode electrode 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 direct contact between electrolytic products in the cathode and anode regions, thereby reducing the occurrence of side reactions.

[0050] The lower end of the electrolytic cell 10 is provided with an electrolytic cell inlet 16 connected to the cathode chamber and the anode chamber, and the upper end is provided with an electrolytic cell outlet, including a first outlet 17 connected to the cathode chamber and a second outlet 18 connected to the anode chamber, which are used to output the gas-containing electrolyte in the cathode chamber and the anode chamber respectively; the electrolyte enters the electrolytic cell 10 from the bottom and flows from bottom to top, and the gas-containing electrolyte produced after electrolysis is discharged from the electrolytic cell outlet.

[0051] A composite woven plate mesh 19 is installed in both the cathode chamber and the anode chamber to induce the growth of fine bubbles in the gas-liquid mixture generated by electrolysis and to guide them out; the composite woven plate mesh 19 includes hydrophilic silk threads and hydrophobic silk threads, wherein:

[0052] like Figure 3 and Figure 4 As shown, the hydrophilic silk thread and the hydrophobic silk thread are spirally twisted to form a "twisted" woven silk thread, and the woven silk thread adopts an Ω-shaped weaving to form a multi-scale void network structure with Ω-shaped channels; specifically, the multi-scale void network structure adopts a two-dimensional mesh stacking structure, and the stacking method is that the channels in different stacking layers correspond to each other, forming a flow channel on a macro scale.

[0053] In the composite woven plate mesh 19, the volume ratio of the hydrophilic yarn to the hydrophobic yarn is 3:1 to 5:1. Figure 6 As shown, 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 19 is 89%~98%.

[0054] like Figure 5 and Figure 6 As shown, when the gas-containing electrolyte produced by electrolysis passes through the composite woven plate mesh 19, its porous structure will intensify the liquid turbulence and increase the collision probability of micro bubbles. Since the hydrophobic silk thread has the characteristic of low wettability, it provides agglomeration sites for micro bubbles at the micro level, continuously inducing the micro bubbles to aggregate and grow; at the same time, the flow channel structure formed at the macro level induces larger bubbles to detach quickly, reducing the accumulation and blockage of bubbles.

[0055] In addition, the composite woven plate mesh 19 installed between the electrode and the plate can also play a role in supporting the electrode. The composite woven structure is not easily corroded in alkaline electrolyte.

[0056] The material of the hydrophilic thread is selected from one or more of platinum, nickel, indium tin oxide, ruthenium oxide and graphene;

[0057] The material of the hydrophobic thread is selected from one or more of polyurethane, polyolefin, polycarbonate, polyamide, polyacrylonitrile, polyester, PTFE, FEP, ETFE and PFA.

[0058] In the braided silk thread, the spacing between the hydrophilic silk thread or the hydrophobic silk thread is 0.08~1.2mm; the diameter of the hydrophilic silk thread or the hydrophobic silk thread is 80~180 , the weaving density is 50~150 mesh.

[0059] Preferably, the electrolytic cell 10 is a cylindrical structure with a diameter of 1000 mm and a height of 2000 mm.

[0060] In specific applications, one or more composite woven plate meshes 19 may be installed in the cathode chamber and the anode chamber;

[0061] 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 300-500 mm away from the outlet of the electrolytic cell.

[0062] If there are multiple composite woven plate meshes 19, they are arranged in steps from small to large porosity along the electrolyte flow direction, specifically:

[0063] When there are two composite woven plate meshes 19, they are arranged in sequence along the electrolyte flow direction according to the porosity of 91%-94% and 95%-98% respectively;

[0064] When there are three composite woven plate meshes 19, they are arranged in sequence along the flow direction of the electrolyte with porosities of 89%-91%, 91%-94%, and 95%-98% respectively.

[0065] When the gas-liquid mixture passes through the composite woven plate mesh 19 with different porosities arranged in a stepped manner from bottom to top, the composite woven plate mesh 19 at the bottom has a smaller porosity, which can better intercept small bubbles and make them gather together. The bubbles move along the flow channel and gather together and grow under the action of the liquid phase drag force; while the composite woven plate mesh 19 at the top has a larger porosity, which can make the large bubbles formed by the gathering quickly detach without causing blockage of the channel.

[0066] In addition, the composite woven plate mesh 19 is subjected to surface roughening treatment to increase the surface roughness, but the outer surface edge thereof is not subjected to roughening treatment to avoid puncturing the diaphragm 13 .

[0067] Example 2: An electrolysis device using a composite woven plate to gather and separate bubbles

[0068] like Figure 7 As shown, the electrolysis device of this embodiment includes the electrolytic cell 10 of the above-mentioned embodiment 1, two gas-liquid separators 20, two gas processing equipment 30, an alkali liquid mixer 40 and two alkali liquid circulation pumps 50, wherein:

[0069] 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 liquid mixer 40 via the corresponding alkali liquid circulation pump 50, and the alkali liquid 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 processing equipment 30.

[0070] The gas processing equipment 30 is used to receive hydrogen or oxygen from the gas-liquid separator 20 and perform drying and pressurizing treatment on the hydrogen or oxygen to facilitate subsequent data analysis.

[0071] It should be noted that the gas-liquid separator 20, gas processing equipment 30, alkali liquid mixer 40 and alkali liquid circulation pump 50 are all conventional equipment in this field and can be selected according to actual needs. Their specific structures will not be described here.

[0072] The electrolysis method and principle of the electrolysis device using the composite woven plate mesh to gather and separate bubbles are as follows:

[0073] The electrolyte enters the electrolysis chamber from the electrolytic cell inlet 16 at the bottom of the electrolytic cell 10, 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 19 during the rising process. Since the hydrophobic silk threads in the composite woven plate mesh 19 have the characteristic of low wettability, they provide agglomeration sites for the fine bubbles at the micro level, continuously inducing the fine bubbles to gather and grow. The flow channel structure formed at the macro level of the composite woven plate mesh 19 will induce large bubbles to detach quickly, reducing bubble accumulation and blockage.

[0074] Under the action of the alkali liquid circulation pump 50, the large bubbles that are gathered and separated enter the gas-liquid separator 20 together with the electrolyte for gas-liquid separation. After separation, the gas phase enters the gas treatment equipment 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 transported to the alkali liquid mixer 40 through a pipeline to supply liquid to the electrolytic cell 10, thereby realizing the circulation of the electrolyte.

[0075] During electrolysis, the flow rate of the electrolyte in the electrolytic cell 10 is 0.03-0.06 m / s, the current density is 250-652 A / m², and the operating temperature of the electrolytic cell 10 is 65-85° C. (under normal pressure).

[0076] The volume of the electrolyte in the gas-liquid separator 20 is controlled to be 1 / 2 to 3 / 4 of the volume of the gas-liquid separator 20 ; the outlet pressure of the alkali solution circulation pump 50 is 0.8 to 1.6 MPa.

[0077] Example 3

[0078] The electrolysis apparatus of Example 2 was used to electrolyze a 30 wt % potassium hydroxide solution to generate hydrogen and oxygen. The electrolyte inlet volume flow rate was set to 1200 mL / min, the electrolyte flow rate was 0.035 m / s, the current density was 312.5 A / m², and the electrolytic cell operating temperature was 65°C.

[0079] The cathode chamber and the anode chamber are respectively provided with three-level composite woven plate mesh, wherein:

[0080] The material of the hydrophilic silk thread is nickel; the material of the hydrophobic silk thread is polyurethane.

[0081] The spacing between the threads is 0.5 mm, the diameter of both the hydrophilic and hydrophobic threads is 120 μm, and the weave density is 80 mesh. The volume ratio of the hydrophilic to hydrophobic threads is 3:1, and the porosity of the three-level composite woven mesh is 90%, 93%, and 95% from bottom to top, respectively.

[0082] The angle θ between the stacked layers in the composite woven plate mesh and the electrolyte flow direction is 60°.

[0083] Example 4

[0084] The electrolysis device and electrolysis conditions of this embodiment are basically the same as those of Example 3, except that the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread in the composite woven plate mesh is 4:1.

[0085] Example 5

[0086] The electrolysis device and electrolysis conditions of this embodiment are basically the same as those of Example 3, except that the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread in the composite woven plate mesh is 5:1.

[0087] Example 6

[0088] The electrolysis device and electrolysis conditions of this embodiment are basically the same as those of Example 3, except that a composite woven plate mesh is respectively provided in the cathode chamber and the anode chamber, and the porosity of the composite woven plate mesh is 95%.

[0089] Comparative Example 1

[0090] The electrolysis device and electrolysis conditions of this comparative example are basically the same as those of Example 3, except that the composite woven plate mesh is not used.

[0091] Comparative Example 2

[0092] The electrolysis device and electrolysis conditions of this comparative example are basically the same as those of Example 3, except that the composite woven plate mesh is replaced by the porous structure in the invention application CN117165978A.

[0093] Comparative Example 3

[0094] The electrolysis device and electrolysis conditions of this comparative example are basically the same as those of Example 3, except that the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread in the composite woven plate mesh is 2:1.

[0095] Comparative Example 4

[0096] The electrolysis device and electrolysis conditions of this comparative example are basically the same as those of Example 3, except that the volume ratio of the hydrophilic silk thread to the hydrophobic silk thread in the composite woven plate mesh is 1:1.

[0097] Comparative Example 5

[0098] The electrolysis device and electrolysis conditions of this comparative example are basically the same as those of Example 3, except that the composite woven plate mesh is composed only of hydrophobic silk threads.

[0099] Comparative Example 6

[0100] The electrolysis devices and electrolysis conditions of this comparative example and Example 3 are basically the same, except that the composite woven plate mesh is made of woven wires by cross-weaving.

[0101] The bubble size and gas holdup in the electrolyte at the top of the electrolytic cell after electrolysis of the above-mentioned Examples 3 to 6 and Comparative Examples 1 to 5 are shown in Table 1 below. The gas holdup and energy consumption of the electrolysis devices of Example 3 and Comparative Example 6 at different superficial flow rates are compared. Figure 8 and Figure 9 shown.

[0102] Table 1

[0103]

[0104] From the results in Table 1, it can be seen that the composite woven plate mesh of the present invention can significantly increase the size of bubbles in the electrolyte to the millimeter level, and the bubble detachment speed is relatively fast, which can effectively reduce the voltage of the electrolysis chamber, thereby improving the electrolysis efficiency; Comparative Example 1 does not adopt the composite woven plate mesh structure, and produces a small bubble group, resulting in a higher gas content. Comparative Example 2 adopts the porous structure in CN117165978A. Since there is no flow channel, the bubble detachment is irregular and blocked, and the bubble detachment speed is relatively slow, resulting in a higher gas content than Example 3 with a flow channel. Figure 8 and Figure 9 It can be seen that although comparative example 6 also uses braided wire, no flow channel is formed, and the gas holdup and energy consumption are much higher than those of example 3.

[0105] In addition, the volume ratio of hydrophilic threads to hydrophobic threads also affects the gas content. Examples 3 to 5 and Comparative Examples 3 to 5 use hydrophilic threads and hydrophobic threads in different volume ratios. The hydrophobic threads help the bubbles to coalesce and form larger bubbles, while an appropriate amount of hydrophilic threads help the large bubbles formed by coalescence to quickly detach along the flow channel. When the volume ratio of hydrophilic threads to hydrophobic threads is too small, bubble accumulation will increase, and the bubble detachment efficiency will decrease, resulting in a longer residence time of bubbles in the electrolytic cell and an increase in gas content. When the ratio of the two is too large, the attachment sites of small bubbles will decrease, reducing the probability of bubble coalescence in the electrolyte and reducing the overall bubble size. Therefore, the volume ratio of hydrophilic threads to hydrophobic threads is preferably 3:1 to 5:1.

[0106] The above are merely specific embodiments of the present application to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may 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 the embodiments shown herein, but rather is intended to conform to the widest scope consistent with the principles and novel features of the present application.

Claims

1. An electrolytic cell, characterized in that: The electrolytic cell comprises a plurality of electrolytic chambers connected in parallel, wherein each electrolytic chamber comprises 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 being formed between the cathode plate and the cathode electrode, and an anode chamber being 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 the 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; Composite woven plate mesh is installed in the cathode chamber and the anode chamber; The composite woven plate mesh is used to induce the growth of fine bubbles in the gas-liquid mixture generated by electrolysis and to guide them out; the composite woven plate mesh includes hydrophilic silk threads and hydrophobic silk threads, wherein: The hydrophilic silk thread and the hydrophobic silk thread are spirally twisted to form a "twisted" braided silk thread. The braided silk thread adopts an Ω-shaped braid to form a multi-scale void network structure with Ω-shaped channels. The multi-scale void network structure is a two-dimensional mesh stacking structure. The stacking method is that the channels in different stacking layers correspond to each other, forming a flow channel on a macro scale. In the composite woven mesh, the volume ratio of hydrophilic silk threads to hydrophobic silk threads is 3:1~5:1, 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 mesh is 89%~98%.

2. The electrolytic cell according to claim 1, characterized in that The material of the hydrophilic thread is selected from one or more of platinum, nickel and graphene; The material of the hydrophobic thread is selected from one or more of polyurethane, polyolefin, polycarbonate, polyamide, polyacrylonitrile, polyester, PTFE, FEP, ETFE and PFA.

3. The electrolytic cell according to claim 1, characterized in that In the braided silk threads, the spacing between the hydrophilic silk threads or the hydrophobic silk threads is 0.08-1.2 mm; the diameter of the hydrophilic silk threads or the hydrophobic silk threads is 80-180 μm, and the braiding density is 50-150 meshes.

4. The electrolytic cell according to claim 1, characterized in that There are 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 steps from small to large porosity along the flow direction of the electrolyte.

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

6. The electrolytic cell according to claim 1, characterized in that The composite woven plate mesh is subjected to surface roughening treatment to increase surface roughness, but the outer surface edge thereof is not subjected to roughening treatment to avoid puncturing the diaphragm.

7. An electrolysis device, characterized in that: The electrolysis device comprises the electrolytic cell according to any one of claims 1 to 6, as well as two gas-liquid separators, two gas treatment devices, an alkali liquid mixer and two alkali liquid circulation pumps, wherein: The mixed liquid inlets of the two gas-liquid separators are respectively connected to the first outlet and the second outlet of the electrolytic cell; their liquid phase outlets are connected to the alkali liquid mixer via the corresponding alkali liquid circulation pump, and the alkali liquid mixer is connected to the electrolytic cell inlet of the electrolytic cell to realize the circulation of the electrolyte; their gas phase outlets are connected to the corresponding gas processing equipment.

8. An electrolysis method, using the electrolysis device according to claim 7, characterized in that: The electrolysis method comprises the following steps: The electrolyte enters the electrolysis chamber 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 tiny bubbles. During the upward process, the tiny bubbles pass through the composite woven plate mesh. Because the hydrophobic silk threads in the composite woven plate mesh have the characteristic of low wettability, they provide coalescence sites for the tiny bubbles at the micro level, continuously inducing the tiny bubbles to gather and grow. The flow channel structure formed at the macro level of the composite woven plate mesh will induce larger bubbles to detach quickly, reducing bubble accumulation and blockage. The large bubbles that are gathered and separated 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 equipment for drying and pressurization treatment. The treated gas can be stored and used.

9. The electrolysis method according to claim 8, characterized in that The flow rate of the electrolyte in the electrolytic cell is 0.03~0.06m / s, and the current density is 250~652A / m²; under normal pressure, the operating temperature of the electrolytic cell is 65~85℃.

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