Bipolar composite electrode, preparation method and water treatment module

Abstract

The invention discloses a bipolar composite electrode, a preparation method and a water treatment module, and relates to the technical field of electrochemical water treatment electrodes. The device specifically comprises an insulating component, an anode plate and a cathode plate, the cathode plate and the anode plate are installed on the two sides of the insulating component respectively, and the opposite faces of the anode plate and the cathode plate are attached and conducted; a boron-doped diamond film layer is arranged on the reaction surface of the anode plate; and packing structures are arranged at the outer edges of the anode plate and the cathode plate, and are used for fixing the cathode plate and the anode plate on the insulating component. The anode plate and the cathode plate are both arranged on the insulating member to form the integrated bipolar composite electrode, the problem that an insulating structural member is needed when the bipolar electrode is assembled and connected with other structural members is solved, when a plurality of bipolar composite electrodes form an electrode group, a lead wire is not needed, the structure is simple and compact, the internal resistance of the electrode group is low, and the reliability is high. And the electrode group adopts a high-voltage low-current power supply mode, so that the power supply control is easy, and the electric energy transmission heating loss is low.

Description

Technical Field

[0001] The present invention relates to the technical field of electrochemical water treatment electrodes, and in particular to a bipolar composite electrode, a preparation method thereof, and a water treatment module. Background Art

[0002] As global water shortages and environmental pollution become increasingly severe, the development of efficient and sustainable water treatment technologies has become an important research direction in the scientific and engineering fields. Electrochemical water treatment technology has attracted much attention due to its environmental friendliness, operational flexibility, and efficient pollutant removal capabilities. Electrodes, as the core components of this technology, directly determine the system's energy efficiency, reaction kinetics, and practical application potential. Optimizing the performance of electrode materials is key to improving the efficiency of electrochemical water treatment: in early studies, materials such as graphite and stainless steel were widely used due to their low cost, but their low catalytic activity and poor stability limited their large-scale application. In recent years, research based on precious metal oxides (such as IrO2 / Ti, RuO2 / Ti), boron-doped diamond (BDD), and transition metal composite electrodes (such as Ti / SnO2) has significantly improved the performance and efficiency of electrodes. Among them, boron-doped diamond electrode materials are recognized as ideal electrode materials for electrochemical water treatment due to their excellent electrochemical properties and other physicochemical properties. Due to the preparation process of boron-doped diamond film materials and their requirements as electrochemical anode materials, the substrate of boron-doped diamond film is generally made of conductive silicon materials or some materials with high thermal stability such as niobium, tantalum, etc., while the corresponding cathode material is generally made of stainless steel, titanium or titanium alloy materials.

[0003] Due to the different materials of the anode and cathode, electrochemical water treatment devices mostly adopt a unipolar electrode scheme, that is, the anode and cathode are respectively placed in a reaction tank or reactor, and both the anode plate and the cathode plate have leads or tabs connected to the power supply. Specifically, a wastewater pollutant electrochemical degradation device proposed by Chinese patent announcement number CN215048908U, wherein the anode plate and the cathode plate are arranged alternately and parallelly from bottom to top in the reaction tank, dividing the reaction tank into a wastewater treatment flow channel that is arranged in a serpentine shape with reciprocating bends and extensions to the left and right, so that harmful substances in the wastewater are oxidized and reduced at the anode and cathode respectively through the electrolysis process and successfully mineralized into harmless inorganic substances to achieve a wastewater purification method.

[0004] In the existing scheme, all anodes and cathodes need to be provided with a conductive connection structure, and the anode and cathode are connected in parallel, making the overall structure relatively cumbersome; at the same time, the conductive connection position is often set at the corner of the electrode, or at a certain point. When the current density of the electrode group is high, the current density at the position farther away from the conductive connection is smaller than that at the position closer to the conductive connection, resulting in uneven current density on the electrode surface. In addition, due to the parallel connection mode of multiple electrodes, the difference in resistance of each electrode will also lead to a relatively large difference in current density between electrodes, affecting the efficiency and effect of electrochemical treatment; in addition, due to the large number of conductive connections and the parallel connection of electrodes, the total current of the electrode group is very high, and the power consumption is relatively high during the power transmission process. It is more difficult for a high-current, low-voltage power supply to accurately control the supply current.

[0005] Therefore, the present application solves the problems in the unipolar electrode group solution, such as the need to set up a separate conductive connection for each electrode plate, which leads to a complex overall structure when the electrode group and electrochemical reaction device are composed, uneven electrochemical current on the electrode surface, excessive heat loss during current transmission, and large power supply current, which is difficult to accurately control. Summary of the Invention

[0006] The main purpose of the present invention is to provide a bipolar composite electrode and a preparation method and a water treatment module to solve the problems of complex structure when monopolar electrodes are used to form electrode groups and electrochemical reactors, uneven electrochemical current, and excessive heat loss caused by large current and difficult to control.

[0007] In order to achieve the above object, the present invention provides a bipolar composite electrode, comprising:

[0008] an insulating member having a through hole in its center;

[0009] A cathode plate and an anode plate are respectively mounted on the inner wall of the hole of the insulating component, and the anode plate and the cathode plate are in contact with each other on one side; a boron-doped diamond film layer is provided on the reaction surface of the anode plate; and

[0010] The sealing structure is arranged at the outer edge of the bonding surface of the anode plate and the cathode plate, and fixes and seals the cathode plate and the anode plate on the insulating component.

[0011] Furthermore, the anode plate and the cathode plate have facing surfaces that are both flat, and the flat surfaces are bonded to each other and are electrically connected.

[0012] Furthermore, the plate surfaces of the cathode plate and the anode plate are both larger than their bonding areas, and the outer edge portions of the cathode plate and the anode plate are fixed to the insulating component.

[0013] Furthermore, a conductive medium is provided between the cathode plate and the anode plate, so that the anode plate, the conductive medium and the cathode plate are connected in series.

[0014] Furthermore, the anode plate uses conductive silicon as a substrate, and a boron-doped diamond film layer is placed on the reaction surface of the conductive silicon; the cathode plate is made of pure titanium, titanium alloy or stainless steel.

[0015] Furthermore, the anode plate is a circular plate, a square plate or a polygonal plate.

[0016] Furthermore, the insulating component is made of an insulating corrosion-resistant material, and the insulating corrosion-resistant material is one of PVC, nylon, PP, epoxy resin, PVDF, PTFE and fiber-reinforced composite materials.

[0017] Furthermore, a flow blocking portion is provided on the outer edge of the insulating component.

[0018] Furthermore, the insulating component is provided with a water distribution, fixing and sealing structure. The water distribution structure refers to a structure on the insulating component for arranging wires or water flows, etc. When in use, the insulating component can be placed with a concave surface facing upward and outward, and water can flow out along the concave surface and other structures under the action of pressure, so that the mass transfer effect of the pollutants in the water through the electrochemical reaction area is better, while avoiding the accumulation of sediment and quickly taking away the bubbles generated by the electrochemical reaction; the fixing structure refers to the hole on the insulating component, that is, the inner edge of the anode plate and the cathode plate, and the inner edge of the hole is fixed with sealant to ensure the fixed position of the anode plate and the cathode plate. After the sealant is installed, the sealing structure can ensure the sealing performance of the sealant, such as filling the inner edge of the hole with waterproof coating to further improve the waterproof performance.

[0019] Furthermore, the number of the anode plates is multiple, and each of the anode plates is within the plate surface coverage range of the cathode plate.

[0020] Furthermore, the sealing structure includes a sealing cavity provided at the edge of the cathode plate close to the anode plate, and the sealing cavity is used to set an insulating sealing material.

[0021] Furthermore, a positive electrode gap is provided between the edge of the anode plate and the insulating component, and the positive electrode gap is connected to the sealing cavity for injecting glue, ie, insulating sealing material, into the sealing cavity.

[0022] Furthermore, the insulating component is provided with a sink extending toward the sealed cavity.

[0023] Furthermore, a flange is provided on a side of the cathode plate facing the anode plate, and the flange is attached to the anode plate.

[0024] The present application also discloses a method for preparing a bipolar composite electrode, which comprises:

[0025] S1: The edge of the anode plate is bonded to the insulating member, and the reaction surface of the anode plate and the insulating member are flush and cured;

[0026] S2: The anode plate and the flat surface of the insulating member are placed on the same horizontal plane, and the cathode plate is assembled on the insulating member so that the cathode plate and the anode plate are in contact and conductive;

[0027] S3: Bonding the edge of the cathode plate to the insulating member until the cathode plate and the insulating member are solidified.

[0028] Furthermore, in step S2, the cathode plate and the anode plate are bonded and connected, including attaching conductive glue to the bonding surface of the anode plate so that the cathode plate and the anode plate are bonded and connected, and / or attaching conductive glue to the bonding surface of the cathode plate so that the cathode plate and the anode plate are bonded and connected.

[0029] The present application also discloses a water treatment module, including a reaction tank and a driving electrode. A plurality of bipolar composite electrodes as described above are installed in the reaction tank at intervals in the same direction. The positive electrode sheet and the negative electrode sheet of the driving electrode are respectively arranged on both sides of the plurality of bipolar composite electrodes for series conduction.

[0030] The above technical solution has the following advantages:

[0031] The present application designs a new bipolar composite electrode, so that the anode plate and the cathode plate are both arranged on the insulating component, which can avoid problems such as warping, misalignment, and low parallelism between the anode and cathode plates during installation, as well as the risk of electrochemical corrosion of the conductive connection structure and the cathode plate during the electrochemical reaction. At the same time, the anode plate, cathode plate and insulating component are assembled and formed, which can improve the convenience of installation and there is no need to adjust the relative position between the anode plate and the cathode plate, greatly improving the accuracy and convenience of installation.

[0032] The present application adopts a water treatment module and places a bipolar composite electrode in the water treatment module, thereby replacing the original situation where the positive and negative electrodes are set separately. The current of the anode plate can flow to the cathode plate, thereby saving the tedious wire connection and increasing the contact surface of the anode plate and the cathode plate. The internal resistance of the entire electrode group is smaller, the energy consumption is lower, and the overall heat energy consumption of the electrode group is reduced, further improving the energy efficiency and treatment effect of the current on the degradation of pollutants in the water body. The mutual support between the anode and cathode and the insulating structure can make the anode and cathode plates thinner, further reducing the volume, reducing weight, and reducing costs. In the process of designing water treatment, the complexity of the overall design is also reduced. The fit between the anode plate and the cathode plate removes the space separating the two, thereby further compressing the aperture of the bipolar composite electrode in the reaction tank and improving the space utilization of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0034] Figure 1 This is a schematic structural diagram of a first embodiment of the present invention;

[0035] Figure 2 Schematic diagram of the cross-section structure of the first embodiment of the present invention;

[0036] Figure 3 For the present invention Figure 2 Schematic diagram of the enlarged structure at A in the middle;

[0037] Figure 4 Schematic diagram of the structure of the second embodiment of the present invention;

[0038] Figure 5 Schematic diagram of the cross-sectional structure of the second embodiment of the present invention;

[0039] Figure 6 For the present invention Figure 5 Schematic diagram of the enlarged structure at B in the middle;

[0040] Figure 7 This is a schematic structural diagram of a third embodiment of the present invention from a first viewing angle;

[0041] Figure 8 2 is a schematic structural diagram of a third embodiment of the present invention from a second viewing angle;

[0042] Figure 9 Schematic diagram of the cross-sectional structure of a third embodiment of the present invention;

[0043] Figure 10 For the present invention Figure 9 Schematic diagram of the enlarged structure at C in the middle;

[0044] Figure 11 It is a structural schematic diagram of the water treatment module of the present invention.

[0045] In the figure: 1. cathode plate; 2. insulating member; 3. anode plate; 4. positive electrode gap; 5. sealing chamber; 6. negative electrode gap; 7. reaction tank. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and do not constitute a limitation of the present invention.

[0047] After careful study, it was found that the existing technology can indeed electrochemically degrade wastewater pollutants, but there are still some deficiencies when the product is used, which leads to problems with the entire product. Specifically, since several positive electrodes and several negative electrodes are evenly distributed in the reaction device, and the positive electrodes and negative electrodes are staggered, because both the positive electrodes and the negative electrodes need to be connected by wires, a parallel wiring method is adopted, and one end of several positive electrodes is connected with the same conductor, and the negative electrodes are also connected with the same conductor. Because the current passing through several pole pieces is collected on the conductor, the current passing through the conductor is too large, and a conductor with a larger conductive cross-section is required to maintain the normal operation of the positive and negative pole pieces; in addition, the conductor and the conductive connection between the conductor and the electrode need to be protected by chemical and electrochemical corrosion and water sealing, resulting in a lot of space waste. In addition, since the electrodes are connected in parallel, the supply of the entire electrode group is insufficient. The electric current is very high, so a large heat loss will be generated in the conductor and all conductive connections, which will not only reduce energy efficiency but also cause equipment failure due to local overheating. The differences between the electrodes themselves and during installation and operation will lead to different equivalent resistances between each electrode pair. Since the electrodes are in a parallel structure, there will be large differences in the current of each electrode pair. If the resistance between the electrode pairs is too large or too small, the corresponding current will be too small or too large. The difference between the actual operating current and the optimal operating current will lead to a decrease in the overall current efficiency and the risk of electrode damage. In addition, since the conductive connection of the electrode is set at a certain edge or corner of the electrode, the current density at a position farther away from the conductive connection will be smaller than the current at a position closer to the conductive connection. The uneven current density will also lead to a decrease in electrochemical treatment efficiency and the risk of electrode damage.

[0048] like Figure 1-Figure 3As shown, a bipolar composite electrode includes an insulating member 2, an anode plate 3 and a cathode plate 1. A through hole is opened in the middle of the insulating member 2. The cathode plate 1 and the anode plate 3 are respectively mounted on the inner wall of the hole of the insulating member 2. The anode plate 3 and the cathode plate 1 are bonded and connected on the opposite sides. The reaction surface of the anode plate 3 is provided with a boron-doped diamond film layer. The outer edge of the bonding surface of the anode plate 3 and the cathode plate 1 is provided with a sealing structure. The sealing structure fixes the cathode plate 1 and the anode plate 3 on the insulating member 2 and is used to seal the gap on the outer edge of the bonding surface of the anode plate 3 and the cathode plate 1 to form a current collection from the anode plate 3 to the cathode plate 1. In the middle flow direction, the insulating component 2 is used to support the anode plate 3 and the cathode plate 1, so that the insulating component 2, the anode plate 3 and the cathode plate 1 are assembled into a whole, which is convenient for installation in the required product. There is no need to use the method of installing the positive and negative electrodes separately to achieve water treatment, which improves the convenience of installation. At the same time, the anode plate 3 and the cathode plate 1 are fixed on the insulating component 2 through the sealing structure, which can avoid the problems of the anode plate 3 and the cathode plate 1 being broken and warped during installation. The anode plate 3 and the cathode plate 1 after installation remain in a horizontal state, ensuring that the contact area between the two remains flat, improving the diversion effect, and reducing heat loss. The sealing structure blocks the gap between the anode plate 3 and the cathode plate 1, and insulates the edges of the anode plate 3 and the cathode plate 1 to prevent arcing between the anode plate 3 and the cathode plate 1, aggravating the dissolution of the anode plate 3 and affecting the use. At the same time, it increases the current density of the current flowing from the anode plate 3 to the cathode plate 1, thereby improving the working efficiency of the composite electrode.

[0049] Specifically, the side of the cathode plate 1 facing the anode plate 3 can be filled with an insulating sealing material, and there is no need to adopt a flat structure. In the present application, it is preferred that the facing sides of the anode plate 3 and the cathode plate 1 are both flat, and the flat surfaces are bonded to each other and connected, so that the anode plate 3 and the cathode plate 1 are bonded to each other, further improving the close fit between the two to avoid the risk of warping, breakage, etc.; the anode plate 3 and the cathode plate 1 can be fixed by brazing or gluing, and the current of the anode plate 3 can flow from the bonded part to the cathode plate 1.

[0050] To improve the convenience of installation, the surface of the cathode plate 1 and the anode plate 3 are larger than their fitting area, and the outer edge parts of the cathode plate 1 and the anode plate 3 are fixed to the insulating component 2, so that there is a sufficient conductive contact surface between the anode plate 3 and the cathode plate 1. At the same time, the uncontacted edge areas of the anode plate 3 and the cathode plate 1 can also be fully utilized and can be fixed to the insulating component 2 in different ways.

[0051] In addition, a conductive medium may be provided between the cathode plate 1 and the anode plate 3, so that the anode plate 3, the conductive medium, and the cathode plate 1 are connected in series. The conductive medium conducts current, and the current flows sequentially from the anode plate 3, the conductive medium, and the cathode plate 1. The conductive medium may be in the form of a plate, a film, or a liquid. The anode plate 3 and the cathode plate 1 rest against the plate or film, which, on the one hand, can achieve pre-positioning, and on the other hand, improve the conductivity between the anode plate 3 and the cathode plate 1. The plate must be made of a conductive material, such as a metal plate or a graphite plate. The conductive medium may also be in the form of a conductive adhesive, a conductive paste, or a conductive tape to improve the conductivity between the anode plate 3 and the cathode plate 1. In the present application, it is preferred to groove the inner wall of the hole of the insulating member 2 so that the anode plate 3 and the cathode plate 1 fall into the corresponding grooves, respectively, to achieve the pre-positioning effect. Conductive adhesive is then applied to the joint of the anode plate 3 and the cathode plate 1 to improve conductivity and also improve the adhesion between the cathode plate 1 and the anode plate 3.

[0052] The anode plate 3 is a circular plate, a square plate or a polygonal plate, and can be formed in a variety of ways, as shown below:

[0053] Example 1:

[0054] like Figure 1-Figure 3 As shown, the insulating member 2 of this embodiment is a circular plate with a hole formed in the middle of the circular plate. A sink is provided at the edge of the hole, so that the cathode plate 1 can be placed on the edge of the sink. The anode plate 3 is attached to the cathode plate 1 and is flush with the side wall of the insulating member 2, thereby realizing the flow path of the current from the anode plate 3 to the cathode plate 1. In addition, a conductive medium is provided between the anode plate 3 and the cathode plate 1 to facilitate the flow of current from the anode plate 3, the conductive medium and then to the cathode plate 1. The conductive medium can be a metal plate or a graphite plate, or it can be welded or coated with conductive glue at the joint of the anode plate 3 and the cathode plate 1. The sealing structure seals the edge gaps of the anode plate 3 and the cathode plate 1 to prevent water from seeping in.

[0055] In this embodiment, the sealing structure is a sealing cavity 5 in which an insulating sealing material can be set at the edge of the cathode plate 1 facing the anode plate 3. The insulating sealing material can be selected from sealant and sealing gasket. The sealant flows into the sealing cavity 5 and waits for it to solidify. The sealing gasket is directly filled in the sealing cavity 5. It is preferred to use sealant to further improve the sealing effect between the anode plate 3 and the cathode plate 1 to prevent liquid from penetrating between the anode plate 3 and the cathode plate 1, so as to avoid causing electric arc or accelerating the corrosion of the anode plate 3, and also to improve the sealing effect between the anode plate 3 and the cathode plate 1; if a sealing gasket is installed in the sealing cavity 5, the edge of the sealing gasket needs to be tightly glued to the edge of the anode plate 3 and the cathode plate 1 with glue.

[0056] Example 2:

[0057] like Figure 4-Figure 6As shown, the anode plate of this embodiment is a quadrilateral plate, or a hexagonal plate. The specific shape can be designed according to needs. This embodiment preferably uses a quadrilateral plate, and a hole is formed in the middle of the quadrilateral plate. The hole can be a square hole, a circular hole or an elliptical hole. The specific shape needs to be designed according to the shape of the anode plate 3 and the cathode plate 1. In this embodiment, a sink is provided at the edge of the hole of the insulating component 2, so that the anode plate 3 and the cathode plate 1 can fit in the sink, ensuring that the anode plate 3 and the cathode plate 1 fit more tightly.

[0058] In this embodiment, the sealing structure is a groove on the edge of the cathode plate 1 to form a sealed cavity 5 that can accommodate an insulating sealing material. The insulating sealing material can be a sealant or a sealing gasket, preferably a sealant. When applying, the sealant should be more than the sealing cavity 5. When the anode plate 3 and the cathode plate 1 are attached, the sealant will gradually penetrate into the gap between the cathode plate 1 and the sinking platform, and the gap between the anode plate 3 and the sinking platform, which can further improve the sealing effect between the anode plate 3 and the cathode plate 1 to prevent liquid from flowing between the anode plate 3 and the cathode plate 1, so as to avoid causing an arc or accelerating the corrosion of the anode plate 3. In addition, a sealing gasket can also be installed in the sealing cavity 5. The edge of the sealing gasket needs to be tightly glued to the sealing cavity 5 with glue, and then the cathode plate 1 is attached to the sinking platform.

[0059] Example 3:

[0060] like Figure 7-10 As shown, in this embodiment, the number of anode plates 3 is set to be multiple, and each anode plate 3 is within the plate surface coverage range of the cathode plate 1. Specifically, if the anode plate 3 is in the shape of a circular plate, the insulating member 2 is provided with a square groove for placing the cathode plate 1 on one side of the inner edge, and a plurality of circular holes for placing the anode plates 3 are provided on the other side. A single cathode plate 1 completely covers and fits a plurality of anode plates 3, so that the current of the anode plate 3 can flow to the cathode plate 1; in addition, a conductive medium can also be provided between the anode plate 3 and the cathode plate 1, so as to realize the current flowing from the anode plate 3 and the conductive medium to the cathode plate 1. It should be noted that the shapes of the square cathode plate 1 and the circular anode plate 3 in this embodiment are not fixed, and are only one of the shapes listed in this embodiment.

[0061] In this embodiment, the sealing structure is a sealing cavity 5 that can accommodate an insulating sealing material at the edge of the cathode plate 1 facing the anode plate 3. The insulating sealing material can be selected from sealant and sealing gasket. Preferably, sealant is used to further improve the sealing effect between the anode plate 3 and the cathode plate 1 to prevent liquid from penetrating between the anode plate 3 and the cathode plate 1, thereby preventing electric arcing or accelerating the corrosion of the anode plate 3. If a sealing gasket is installed in the sealing cavity 5, the edge of the sealing gasket needs to be tightly glued to the sealing cavity 5 of the cathode plate 1 with glue, and then the blank space in the sealing cavity 5 is filled with sealant to achieve the effect of sealing and fixing.

[0062] In the above-mentioned embodiment 1, embodiment 2 and embodiment 3, the anode plate 3 uses conductive silicon as the base material, and a boron-doped diamond film layer is formed on the reaction surface of the conductive silicon. The cathode plate 1 is made of pure titanium, titanium alloy or stainless steel. Since silicon is brittle and fragile, the risk of silicon breakage is effectively prevented after the anode plate 3 and the cathode plate 1 are bonded together; the conductive glue can improve the sealing effect and the conductive effect between the anode plate 3 and the cathode plate 1. The conductive glue can be made of an adhesive and conductive particles. The adhesive can be epoxy resin, and the conductive particles can be metal powder or graphite powder. The metal powder can be made of silver, copper, platinum, aluminum, tin and other materials or their composite materials to achieve a conductive effect. The conductive glue is injected into the sealing cavity 5 so that the conductive glue seals the edges of the anode plate 3 and the cathode plate 1, while improving the sealing performance and the conductive effect; the sealant or sealing gasket can avoid the risk of water seepage between the anode plate 3 and the cathode plate 1.

[0063] like Figure 3 、 Figure 6 and Figure 10 As shown, a negative electrode gap 6 is provided between the edge of the cathode plate 1 and the insulating member 2, and a positive electrode gap 4 is provided between the edge of the anode plate 3 and the insulating member 2. The positive electrode gap 4 is connected to the sealed cavity 5 for the glue to flow into the sealed cavity 5. The positive electrode gap 4 can be filled with glue to seal and fix the anode plate 3 and the insulating member 2, and the negative electrode gap 6 can be filled with glue to seal and fix the cathode plate 1 and the insulating member 2, thereby achieving the overall fixation of the anode plate 3, the cathode plate 1 and the insulating member 2. In the first and third embodiments of the present application, the sealed cavity 5 is opened at the edge of the cathode plate 1 facing the anode plate 3. If the sealed cavity 5 is filled with glue, the positive electrode gap 4 is connected to the sealed cavity 5, so that the glue can flow from the positive electrode gap 4 into the sealed cavity 5, which can greatly improve the overall glue filling effect. In embodiment 2 of the present application, since the sinking platform of the insulating component 2 extends toward the gap between the anode plate 3 and the cathode plate 1, the sinking platform of the insulating component 2 compacts the glue in the sealed cavity 5. The installation steps are as follows: first, the anode plate 3 is installed on the insulating component 2 and the glue is filled on its edge. Then, the cathode plate 1 is assembled on the sinking platform of the insulating component 2, so that the glue penetrates from the sealed cavity 5 into the gap parts on both sides of the sinking platform. The positive electrode gap 4 and the negative electrode gap 6 can also be filled with glue separately until they are solidified after filling. At this time, there is no need for the positive electrode gap 4 or the negative electrode gap 6 to be connected to the sealed cavity 5, so as to ensure the fixation of the anode plate 3, the cathode plate 1 and the insulating component 2.

[0064] In the above embodiment, the outer edge of the insulating member 2 is provided with a flow blocking portion, which is used to increase the creepage distance, thereby reducing other branches of the current in the water treatment device and concentrating the current in the liquid from the anode plate 3 to the cathode plate 1. The insulating member 2 is also made of an insulating and corrosion-resistant material, specifically one of PVC, nylon, PP, epoxy resin, PVDF, PTFE and fiber-reinforced composite materials, or a ceramic material such as Al2O3, with a temperature resistance of more than 80 degrees Celsius. The anode plate 3 is a circular plate, a square plate, or a polygonal plate, and the specific shape can be selected according to the installation requirements.

[0065] Specifically, the blocking portion can be widened at the edge of the insulating component 2 to avoid problems such as a large number of electrodes in series, a high supply voltage of the electrode group, and leakage between the electrode groups. In addition, the blocking portion can also adopt different shapes, such as a T-shaped or umbrella-shaped cross-section to form water distribution, sealing, fixing and other structures.

[0066] like Figure 6 As shown, in order to adjust the fitting distance between the anode plate 3 and the cathode plate 1, a flange is provided on the side of the cathode plate 1 facing the anode plate 3, and the flange is fitted to the anode plate 3, or a conductive medium is provided between the flange and the anode plate 3. The shape of the flange is equivalent to that of the anode plate 3, so that the position of the two is more accurate when fitting, and it is also convenient to attach glue to the edges of the flange and the anode plate 3, or to facilitate the close fitting of the anode plate 3 and the flange, thereby improving the conductive effect.

[0067] The present application also discloses a method for preparing a bipolar composite electrode, which comprises:

[0068] S1: The edge of the anode plate 3 is bonded to the insulating member 2, and the reaction surface of the anode plate 3 is flush with the insulating member 2 and cured; in step S1, the edge of the anode plate 3 is attached with sealant and bonded flush with the insulating member 2, and then curing can be completed by heating.

[0069] S2: The flat surfaces of the anode plate 3 and the insulating component 2 are placed on the same horizontal plane, and the cathode plate 1 is assembled on the insulating component 2, so that the cathode plate 1 and the anode plate 3 are bonded and conductive; wherein, the anode plate 3 and the cathode plate 1 are bonded and conductive, including attaching conductive glue to the bonding surface of the anode plate 3, so that the cathode plate 1 and the anode plate 3 are bonded and conductive, and / or attaching conductive glue to the bonding surface of the cathode plate 1, so that the cathode plate 1 and the anode plate 3 are bonded and conductive, the conductive glue is used to fill between the anode plate 3 and the cathode plate 1, and during production, conductive glue can be attached to the bonding surface of the anode plate 3, or to the bonding surface of the cathode plate 1, or to both, thereby completing the conductive bonding.

[0070] S3: Bond the edge of the cathode plate 1 to the insulating member 2 until the cathode plate 1 and the insulating member 2 are cured. When the edge of the cathode plate 1 is in contact with the insulating member 2, a sealant can be applied to the edge of the cathode plate 1 to bond the cathode plate 1 to the insulating member 2. Alternatively, the cathode plate 1 can be directly bonded to the anode plate 3 to achieve conduction and bonding using a conductive adhesive. Glue is then poured onto the edge of the cathode plate 1, and finally cured by heating.

[0071] During the preparation process, since the anode plate 3 is made of silicon wafer and is relatively thin, it is easy to break. In step S2 of the present application, when the cathode plate 1 and the anode plate 3 are installed, the cathode plate 1 will press down on the anode plate 3 so that the silicon wafer and the insulating component 2 are on the same horizontal plane. The force can be evenly distributed on the insulating component 2 and the anode plate 3, which can greatly avoid the risk of breakage of the anode plate 3 due to uneven force.

[0072] like Figure 11 As shown, a water treatment module includes a reaction tank 7 and a driving electrode. A plurality of the above-mentioned bipolar composite electrodes are installed in the reaction tank 7 at intervals in the same direction. The plurality of bipolar composite electrodes form an electrode group. The anode and cathode plates of the driving electrode are respectively arranged on both sides of the electrode group for conducting in series. In the water treatment module, the electrolysis method is used to treat wastewater. The plurality of bipolar composite electrodes are placed in the reaction tank 7 in sequence. The liquid is used as the conductive medium. The anode plate of the driving electrode has a high potential. The current flows from the anode plate in sequence from the anode plate 3 of the plurality of bipolar composite electrode groups and flows out from the cathode plate 1, and finally flows to the cathode plate of the driving electrode. The barrier portion can separate the two adjacent bipolar composite electrode groups to avoid the cross-flow of pollutants, and also increase the The resistance between adjacent bipolar composite electrode groups causes the current to be concentrated on the anode plate 3 and the cathode plate 1, thereby improving the electrolysis efficiency. In the reaction tank 7, the wastewater in the reaction tank 7 flows between the two adjacent bipolar composite electrodes and undergoes an electrochemical oxidation-reduction reaction to degrade the pollutants in the water. A plurality of bipolar composite electrodes are connected in series to form a pathway. Compared with the existing parallel electrode groups, excessive conductive connections can be eliminated, and the conductive structure can be avoided from being connected inside and outside the reaction tank 7, causing structural, energy consumption and stability problems. The present application only adopts the method of laminating the anode plate 3 and the cathode plate 1 to realize current conduction, or adding a conductive medium in the middle, which not only ensures the installation of the anode plate 3 and the cathode plate 1, but also improves the overall safety performance and avoids the risk of water seepage between the anode plate 3 and the cathode plate 1.

[0073] The cathode plate 1 and the anode plate 3 of the present application are made of different materials, which avoids the problem of needing to separately install the insulating structural member 2 when assembling the bipolar electrode and connecting it with other structural members. At the same time, when several bipolar composite electrodes are combined into an electrode group, no lead wire is required, the structure is simple and compact, the internal resistance of the electrode group is low, and the current is more uniform. The electrode group adopts a high-voltage and low-current power supply method, the power supply control is easy, and the heat loss during power transmission is low.

[0074] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by using the contents of the present description and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A bipolar composite electrode, characterized in that: include: An insulating member (2) having a through hole in its center; A cathode plate (1) and an anode plate (3) are respectively mounted on the inner wall of the hole of the insulating component (2), and the anode plate (3) and the cathode plate (1) are bonded and connected on their facing sides; a boron-doped diamond film layer is provided on the reaction surface of the anode plate (3); as well as The sealing structure is arranged at the outer edge of the bonding surface of the anode plate (3) and the cathode plate (1), and fixes and seals the cathode plate (1) and the anode plate (3) on the insulating member (2) to form a concentrated current flow from the anode plate (3) to the cathode plate (1).

2. The bipolar composite electrode according to claim 1, wherein The anode plate (3) and the cathode plate (1) have facing surfaces that are both flat, and the flat surfaces are bonded to each other and are electrically connected.

3. The bipolar composite electrode according to claim 2, wherein: The plate surfaces of the cathode plate (1) and the anode plate (3) are both larger than their bonding areas, and the outer edge portions of the cathode plate (1) and the anode plate (3) are fixed to the insulating component (2).

4. The bipolar composite electrode according to claim 3, wherein A conductive medium is provided between the cathode plate (1) and the anode plate (3), so that the anode plate (3), the conductive medium and the cathode plate (1) are connected in series.

5. The bipolar composite electrode according to claim 1, wherein The anode plate (3) uses conductive silicon as a base material, and the cathode plate (1) is made of pure titanium, titanium alloy or stainless steel.

6. The bipolar composite electrode according to any one of claims 1 to 5, characterized in that: The anode plate (3) is circular, square or polygonal.

7. The bipolar composite electrode according to any one of claims 1 to 5, characterized in that: The insulating component (2) is made of an insulating corrosion-resistant material, and the insulating corrosion-resistant material is one of PVC, nylon, PP, epoxy resin, PVDF, PTFE and fiber-reinforced composite materials.

8. The bipolar composite electrode according to any one of claims 1 to 5, characterized in that: The outer edge of the insulating component (2) is provided with a flow blocking portion.

9. The bipolar composite electrode according to any one of claims 1 to 5, characterized in that: The insulating component (2) is provided with a water distribution structure.

10. The bipolar composite electrode according to any one of claims 1 to 5, characterized in that: The number of the anode plates (3) is set to be multiple, and each of the anode plates (3) is within the plate surface coverage range of the cathode plate (1).

11. The bipolar composite electrode according to claim 1, wherein The sealing structure comprises a sealing cavity (5) provided at the edge of the cathode plate (1) close to the anode plate (3), and the sealing cavity (5) is used to be filled with an insulating sealing material.

12. The bipolar composite electrode according to claim 11, wherein: A positive electrode gap (4) is provided between the edge of the anode plate (3) and the insulating component (2); the positive electrode gap (4) is in communication with the sealing cavity (5) for injecting insulating sealing material into the sealing cavity (5).

13. The bipolar composite electrode according to claim 11, wherein: The insulating component (2) is provided with a sink extending toward the sealed cavity (5).

14. The bipolar composite electrode according to claim 1, wherein The cathode plate (1) is provided with a flange on a side facing the anode plate (3), and the flange is attached to the anode plate (3).

15. The method for preparing a bipolar composite electrode according to any one of claims 1 to 14, characterized in that: The method includes: Step S1: bonding the edge of the anode plate (3) to the insulating member (2), flushing the reaction surface of the anode plate (3) with the insulating member (2), and curing; Step S2: The anode plate (3) and the flat surface of the insulating member (2) are placed on the same horizontal plane, and the cathode plate (1) is assembled on the insulating member (2) so that the cathode plate (1) and the anode plate (3) are in contact with each other; Step S3: bonding the edge of the cathode plate (1) to the insulating component (2) until the cathode plate (1) and the insulating component (2) are solidified.

16. The method for preparing a bipolar composite electrode according to claim 15, wherein: In step S2, the bonding of the cathode plate (1) and the anode plate (3) includes attaching a conductive adhesive to the bonding surface of the anode plate (3) so that the cathode plate (1) and the anode plate (3) are bonded and conductive, and / or the bonding surface of the cathode plate (1) is attached with a conductive adhesive so that the cathode plate (1) and the anode plate (3) are bonded and conductive.

17. A water treatment module, characterized in that: The invention comprises a reaction tank (7) and a driving electrode, wherein a plurality of bipolar composite electrodes as claimed in any one of claims 1 to 14 are installed in the reaction tank (7) at intervals in the same direction, and the positive electrode sheet and the negative electrode sheet of the driving electrode are respectively arranged on both sides of the plurality of bipolar composite electrodes for series conduction.

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