A water electrolysis hydrogen production device and method with turbulence enhancement module

Abstract

The present invention belongs to the technical field of water electrolysis hydrogen production, and discloses a water electrolysis hydrogen production device and method with a turbulence enhancement module, wherein the end pressure plate comprises a cathode end pressure plate and an anode end pressure plate, and a square groove for placing a flow field module is provided in the center of the inner side of the end pressure plate; the flow field module comprises a cathode flow field module and an anode flow field module, one side is smooth, and the other side is provided with a serpentine thread flow channel; the metal electrode comprises a metal cathode and a metal anode, which are porous material electrodes; and the diaphragm is located between the cathode end pressure plate and the anode end pressure plate. The present invention uses the flow field module as a turbulence enhancement module, which can enhance the mass transfer effect in the flow channel, and the electrolyte flushes the electrode inside the flow field, enhances the gas-liquid mass transfer capacity, improves the water electrolysis efficiency, facilitates the cleaning of the flow field, reduces the difficulty of assembly, can cope with various types and thicknesses of electrodes, can realize the switching of different flow fields, and adapt to two water electrolysis conditions of alkaline anion exchange membrane water electrolysis and proton exchange membrane water electrolysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of water electrolysis hydrogen production, and in particular relates to a water electrolysis hydrogen production device and method with a turbulence enhancement module. Background Art

[0002] At present, hydrogen energy, as an ideal form of energy, can accelerate the adjustment of energy structure and help achieve the two carbon goals. Anion exchange membrane (AEM) and proton exchange membrane (PEM) water electrolysis hydrogen production technology has become an important research direction. Water electrolysis hydrogen production is considered to be the most promising hydrogen production technology due to its compact structure and high hydrogen production efficiency. When the electrolyzer is in operation, electrochemical reactions, mass transfer and heat transfer phenomena are involved inside.

[0003] At present, the electrolysis efficiency of alkaline electrolyzer (AWE) is basically around 60%, and the electrolysis efficiency of proton exchange membrane electrolyzer (PEM) is around 75%. This is because in order to ensure that the target current density is achieved, it is necessary to apply too large a voltage at both ends of the electrolysis chamber, resulting in a low actual efficiency. In order to reduce the actual voltage loaded in the electrolysis chamber, from the catalyst level, better non-precious metal catalysts are needed to achieve lower overpotentials at the cathode and anode; at the electrolyzer structure level, more research is needed to confirm the influence of electrolyzer flow channel structure parameters on water electrolysis performance, so as to support the industrial application and development of high-performance electrolyzers.

[0004] The electrode plate is one of the core components inside the electrolyzer. The flow channel and flow field structure on the electrode plate has a key influence on the efficiency of water electrolysis. The flow channel structure can determine the gas-liquid exchange efficiency between the electrolyte and the electrode, and can promptly remove the product bubbles generated on the electrode surface through the flow of the electrolyte, thereby improving the electrolysis efficiency of the electrolyzer.

[0005] A reasonable flow channel structure can improve the water distribution, pressure distribution and heat distribution inside the electrolyzer, increase hydrogen production and extend the service life of the electrolyzer. At present, a large number of studies have shown that the failure of bubbles to be detached from the electrode surface in time is an important reason for the reduction of electrolysis efficiency. The existing flow channel design is prone to bubble blockage and insufficient gas-liquid exchange capacity when the electrolyte inlet flow rate is not high.

[0006] The traditional single-chamber electrolyzer is a multi-level stack of end-pressure electrode plates, diaphragms, electrodes and other components that are tightly pressed together by bolts. Usually, an outlet is set at the top of the electrolyzer and a water inlet is set at the bottom, and a water pump is used to complete the continuous supply of electrolyte during the reaction. The diaphragm plays the role of separating hydrogen and oxygen gases between the two electrodes. Complex flow channels are engraved on the electrode plates to improve the gas-liquid exchange inside the electrolyzer. However, when using electrodes with porous structures, the generated hydrogen and oxygen bubbles are usually easy to be retained inside the porous electrodes. Excessive retention of bubbles will cause the actual contact point between the electrode and water to be greatly reduced, which seriously affects the actual performance of water electrolysis. Previous studies have shown that the bubble coverage rate on the electrode surface is a key factor restricting the electrode current density. Therefore, during the electrolysis process, higher pressure and electrolyte flow are often required to flush the electrode surface, discharge bubbles in the porous electrode in time, and increase the gas-liquid exchange capacity.

[0007] The flow channels on the electrode plates are usually slender and narrow (the flow channels are usually non-through grooves of about 1 mm wide and no more than 1 mm deep). This traditional flow channel has a weak ability to flush the electrodes. The electrolyte has limited ability to carry away bubbles from the electrode surface at the rated electrolyte flow rate. In addition, once the flow channel is blocked during use, it is difficult to disassemble and clean.

[0008] The functions of the plate include conducting electricity, providing water paths, separating oxygen and hydrogen, supporting the electrolyzer, and providing heat conduction. Therefore, the plate material requires high conductivity, corrosion resistance, low air permeability, strong mechanical strength, and high thermal conductivity. Plates plated with precious metals (such as Au and Pt) are still the best choice, but the introduction of precious metals greatly increases the cost. In the cost of the electrolyzer, the cost of the plate accounts for more than 60% of the cost of the electrolyzer, so it is very important to build a flow channel module separated from the plate and improve the processing method of the plate to reduce costs and improve machinability.

[0009] The end pressure plate is the main pressure-bearing part of the electrolytic cell, and is usually made of thick steel plates. In the electrolytic cell, the end pressure plate is a component that clamps the internal electrodes, diaphragms, etc. It also has bolt mounting holes for clamping, positive and negative terminal plates, and external holes of the electrolytic cell. Traditional alkaline electrolytic cells are large in size, and their assembly requires bolts, nuts and disc springs to be tightened. The installation of disc springs also requires guide rings, fixing rings and guide sleeves. The nuts and bolts are subject to great force during the assembly of the electrolytic cell, and must undergo special modulation treatment to increase their strength. Therefore, during the assembly of the electrolytic cell, it is necessary to avoid leakage caused by loose installation, and to prevent deformation or biting caused by uneven force after assembly. Severe cases will cause blockage inside the electrolytic cell, and the technical costs of assembly and disassembly are relatively high.

[0010] Through the above analysis, the problems and defects of the existing technology are as follows: the flow channel structure of the existing electrolytic cell for hydrogen production by electrolysis of water is prone to cause bubble blockage inside the porous electrode and insufficient gas-liquid exchange capacity, resulting in reduced electrolysis efficiency. In addition, the traditional electrolytic cell is difficult to assemble and is not convenient for maintenance and inspection. Summary of the invention

[0011] In view of the problems existing in the prior art, the present invention provides a water electrolysis hydrogen production device and method with a turbulence enhancement module.

[0012] The present invention is implemented in that a water electrolysis hydrogen production device with a turbulence enhancement module comprises:

[0013] The terminal voltage plate includes a cathode terminal voltage plate and an anode terminal voltage plate, which are respectively arranged at the outermost sides of the cathode and the anode, and are used for conducting electricity, fixing and clamping the entire electrolysis device. A square groove for placing a flow field module is provided in the center of the inner side of the terminal voltage plate;

[0014] The flow field module, including the cathode flow field module and the anode flow field module, is a square plate structure, one side is smooth, and the other side is provided with a serpentine thread flow channel, and the beginning and end of the serpentine thread flow channel are respectively provided with vertical inlet and outlet holes, and the inlet and outlet holes correspond to the liquid inlet and gas outlet of the end pressure plate;

[0015] Metal electrodes, including metal cathodes and metal anodes, are porous electrodes;

[0016] The diaphragm is located between the cathode terminal plate and the anode terminal plate.

[0017] Furthermore, a sealing gasket groove is provided around the square groove of the end voltage plate, and a sealing gasket for sealing the entire device is installed in the sealing gasket groove.

[0018] Furthermore, an insulating thickness limiting plate is arranged between the cathode flow field module and the anode flow field module to prevent the cathode terminal voltage plate and the anode terminal voltage plate from being too close to cause a short circuit, and to prevent excessive force applied during clamping from damaging the membrane and the metal electrode structure.

[0019] Furthermore, a copper connection copper plate is installed on the outer side of the end voltage plate for loading external current; holes with the same intervals are arranged on the outer periphery of the end voltage plate for bolt fastening.

[0020] Furthermore, the metal electrode is a foam metal electrode, a woven mesh or an expanded mesh metal, and the thickness of the metal electrode is 0.1-2 mm.

[0021] Furthermore, the sealing gasket is a silicone gasket, and the thickness of the sealing gasket is 0.8 mm thicker than that of the metal electrode.

[0022] Furthermore, the insulating thickness limiting plate is made of epoxy resin plate, and the thickness is the sum of the thickness of the selected metal cathode and the metal anode.

[0023] Furthermore, the diaphragm is an anion exchange membrane or a proton exchange membrane, and the area of ​​the diaphragm is larger than the area of ​​the metal electrode and does not exceed the outer circle of the sealing gasket.

[0024] Furthermore, the square groove of the end pressure plate is provided with plate liquid inlet holes and plate gas outlet holes diagonally distributed throughout the entire end pressure plate.

[0025] Another object of the present invention is to provide a method for producing hydrogen by electrolysis of water, the method comprising:

[0026] Step 1: After installing the electrolytic cell, first conduct a sealing test. Stack the cathode end pressure plate 1-1, cathode flow channel module 2-1, cathode electrode, sealing gasket 3, diaphragm, thickness limit plate 4, sealing gasket 3, anode electrode, anode flow channel module 2-2, and anode end pressure plate 1-2 in this order, tighten them with bolts with insulating sleeves, do not supply power, pass electrolyte through the two electrolyte inlets 14 for 10 minutes, observe whether there is leakage at each connection of the electrolytic cell, and ensure that the electrolytic cell is sealed and clamped before electrolysis;

[0027] Step 2: The electrolyte heated to 60-80°C flows into the liquid inlet holes of the electrode plates at the bottom of both sides, and the electrolytic cell is connected to a regulated DC power supply, wherein the positive electrode of the power supply is connected to the anode wiring copper plate of the electrolytic cell, and the negative electrode of the power supply is connected. According to the required reaction rate, a suitable electrolysis voltage is selected, and the loading voltage range is 1.6-2.5V;

[0028] Step 3: On the cathode side, an electrolyte at a flow rate of 10-100 cc / min is introduced into the cathode porous electrode along the cathode flow field module to generate an electrochemical hydrogen evolution reaction with the electrode. At the same time, the electrolyte also plays a role in gas-liquid exchange. The generated hydrogen bubbles are discharged from the plate outlet holes on the same side of the end pressure plate along with part of the electrolyte.

[0029] Step 4: On the anode side, the electrolyte with the same flow rate undergoes an electrochemical oxygen evolution reaction with the anode porous electrode through the flow field module, and the generated oxygen bubbles are discharged from the anode side plate outlet along with the electrolyte.

[0030] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0031] First, in view of the technical problems existing in the above-mentioned prior art and the difficulty of solving the problems, the technical solutions to be protected by the present invention and the results and data during the research and development process are closely combined to analyze in detail and deeply how the technical solutions of the present invention solve the technical problems, and some creative technical effects brought about after solving the problems. The specific description is as follows:

[0032] The present invention utilizes the flow field module as a turbulence enhancement module, which can enhance the mass transfer effect in the flow channel. The electrolyte flushes the electrodes inside the flow field, enhances the gas-liquid mass transfer capacity, improves the water electrolysis efficiency, facilitates the cleaning of the flow field, and reduces the difficulty of assembly. The water electrolysis hydrogen production device of the present invention can cope with various types and thicknesses of electrodes, can realize the switching of different flow fields, realize zero-electrode spacing high-efficiency electrolysis, and adapt to two water electrolysis conditions: alkaline anion exchange membrane water electrolysis and proton exchange membrane water electrolysis.

[0033] Second, considering the technical solution as a whole or from the perspective of the product, the technical effects and advantages of the technical solution to be protected by the present invention are described in detail as follows:

[0034] The present invention proposes an electrolytic cell fixture that can be separated from the electrode plate and has a turbulent flow field, and is applicable to pure water electrolysis (proton exchange membrane electrolysis) and alkaline solution electrolysis (anion exchange membrane electrolysis). The electrolytic chamber space can be freely adjusted by replacing different insulating thickness limiting plates according to the designed electrode thickness, so as to realize a high current density zero-electrode spacing electrolysis solution.

[0035] Third, as auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects:

[0036] The technical solution of the present invention fills the technical gap in the industry at home and abroad:

[0037] Although my country is currently quite mature in alkaline water electrolysis (AWE) technology and has been widely used in China, its low efficiency, bulky equipment and high operation and maintenance costs are still the main problems currently faced. Anion exchange membrane water electrolysis technology (AEM) and proton exchange membrane water electrolysis technology (PEM) are the emerging water electrolysis technologies that are most concerned in the research field at home and abroad. They have high electrolysis efficiency and compact structure, and are the main technical direction of the hydrogen production industry in the future. However, the research on PEM and AEM has just started in China. At present, most of the research is theoretical and single electrode performance preparation research, and there is no design and research on the overall performance of the electrolyzer. The water electrolysis device proposed in the present invention can first provide a core platform for experimental operation for anion exchange membrane water electrolysis technology and proton exchange membrane electrolysis technology, realize the overall flow field-electrode-diaphragm design and research, and secondly, the water electrolysis device can be used as an independent hydrogen / oxygen production equipment, combined with different scenarios to obtain corresponding applications, such as industrial hydrogen production, small-scale laboratory hydrogen production, medical hydrogen / oxygen inhalation machine, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of a water electrolysis hydrogen production device with a turbulence enhancement module provided in an embodiment of the present invention;

[0039] Figure 2 is a schematic diagram of a unit channel structure of a flow field module provided by an embodiment of the present invention;

[0040] Figure 3 is a schematic diagram of a flow channel distribution structure of a flow field module provided in an embodiment of the present invention;

[0041] Figure 4 It is a schematic diagram of the mass transfer effect between the threaded flow channel and the electrode during the electrolysis process provided by an embodiment of the present invention;

[0042] Figure 5 is a front view of an assembled electrolytic cell provided by an embodiment of the present invention;

[0043] Figure 6 is a side cross-sectional view of an assembled electrolytic cell provided by an embodiment of the present invention;

[0044] Figure 7 is a top cross-sectional view of an assembled electrolytic cell provided by an embodiment of the present invention;

[0045] Figure 8 (a) is a performance curve diagram of the hydrogen production device under different voltages of the enhanced flow field and the traditional flow field provided in the embodiment of the present invention, and (b) is a hydrogen outlet flux diagram of the hydrogen production device under different voltages of the enhanced flow field and the traditional flow field provided in the embodiment of the present invention.

[0046] In the figure: 1. end pressure plate; 2. flow field module; 1-1. cathode end pressure plate; 1-2. anode end pressure plate; 2-1. cathode flow field module; 2-2. anode flow field module; 3. sealing gasket; 4. insulating thickness limit plate; 5. threaded flow channel; 6. air outlet of flow field module; 7. liquid inlet of flow field module; 8. vertical flow channel; 9. porous electrode; 10. electrolyte; 11. hydrogen / oxygen bubbles; 12. bolt through hole; 13. wiring copper plate; 14. plate liquid inlet; 15. plate air outlet. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] In order to enable those skilled in the art to fully understand how to implement the present invention in detail, this section is an explanatory embodiment that expands and describes the technical solution of the claims.

[0049] An embodiment of the present invention provides a hydrogen production device by electrolysis of water. The device is fastened as a whole by bolts. The key component is a flow field module embedded in the end pressure plate that can achieve turbulence enhancement. The flow field module is arranged with a serpentine thread flow groove to achieve gas-liquid mass transfer enhancement and electrolysis efficiency improvement in the electrolysis process in alkaline water electrolysis technology and proton exchange membrane water electrolysis technology.

[0050] Example 1

[0051] The electrolyte used in the water electrolysis hydrogen production device with turbulence enhancement module provided in the embodiment of the present invention is a 30%wt KOH solution. Figure 1 As shown, it includes a pair of end pressure plates 1, a pair of flow field modules 2, a pair of porous metal electrodes 9, a sealing gasket 3, a diaphragm, and an insulating thickness limiting plate 4.

[0052] The single-chamber electrolyzer is composed of a cathode end pressure plate 1-1, a cathode flow channel module 2-1, a cathode electrode, a sealing gasket 3, a diaphragm, a thickness limiting plate 4, a sealing gasket 3, an anode electrode, an anode flow channel module 2-2, and an anode end pressure plate 1-2 stacked in sequence, with the outer contour shape being consistent, and the stacked whole is fastened with bolts to ensure that the internal environment of the electrolyzer is sealed.

[0053] The end voltage plate 1 is made of nickel-plated stainless steel with a thickness of 20mm. The cathode end voltage plate 1-1 is exactly the same structure as the anode end voltage plate, with a bolt through hole 12 with a diameter of 6mm around the outside, an electrolyte inlet 14 with a diameter of 1.6mm, and a gas outlet through hole 15. A threaded hole with a depth of 5mm-7mm is provided concentrically on the outside of the inlet and outlet to connect the straight-through lock nut joint of the inlet and outlet. A 50*50mm flow field module groove with a depth of 5mm is left in the center of the inner side of the plate. The matching sealing gasket 3 adopts a silicone rubber gasket with a rectangular cross-section, a width of 4mm, and a thickness of 0.4mm greater than the thickness of the selected electrode 9.

[0054] The insulating thickness limiting plate 4 is made of epoxy resin, and its thickness is usually 1-4mm according to the thickness of the electrode 9. The plate is provided with 6mm bolt holes corresponding to the end pressure plate around it, and a 64mm*64mm square slot is provided in the center. The two end pressure plates 1 are connected to the insulating thickness limiting plate 4 by bolts.

[0055] A threaded flow channel 5 is arranged inside the flow field module 2. The flow channel single channel model is as follows: Figure 2 As shown, the processing method is to use a CNC milling machine to mill the side surface flat after the thread is drilled until the threaded flow channel 5 is exposed. The thread diameter can be selected from 1-2mm, the pitch can be selected from 0.5-2mm, the maximum depth of the threaded flow channel 5 is 1 / 2-2 / 3 times the thread diameter, and the adjacent spacing of the threaded flow channels 5 is 2mm. After that, a through vertical flow channel 8 is milled between every two threaded flow channels. The depth of the vertical flow channel 8 is the same as the thread depth. The vertical flow channel 8 is located at the position where the first head of each flow channel is connected, as shown in FIG. Figure 3 A serpentine flow channel area is formed in sequence, and a flow field module liquid inlet hole 7 and a flow field module gas outlet hole 6 are respectively provided at the lower right and upper left corners of the flow field module 2, which correspond to the electrolyte inlet 14 and the gas outlet 15 on the inner side of the end voltage plate.

[0056] The mass transfer process between the flow field module 2 and the electrode 9 is shown in the figure Figure 4 As shown. Inside the electrolytic cell, the porous electrode 9 and the flow field module 2 are arranged closely. The electrolyte 10 is pumped into the flow field module 2. The flow of the electrolyte 10 along the flow direction is restricted by the wall of the threaded flow channel 5, which will form a rotating turbulent flow field. A tangential force will be formed along the wall direction, which will flush away the bubbles 11 on the electrode surface close to the flow channel module side. At the same time, the electrolyte 10 is replenished to the porous electrode 9 side in time, so that more hydrogen evolution / oxygen evolution active sites are exposed inside the porous electrode 9 structure, reducing the bubble coverage rate inside the porous electrode 9.

[0057] During installation, first insert the bolt group with the insulating jacket into the cathode terminal plate 1-1, and lay it flat on the table with the inner side facing up. Place the cathode flow field module 2-1 in the corresponding groove of the cathode terminal plate 1-1, place the selected sealing ring gasket 3 in the gasket groove, put in the cut porous cathode electrode, insert the insulating thickness limit plate 4 into the bolt group, put the pre-treated anion exchange membrane into the groove of the insulating thickness limit plate 4, and lay it flat to ensure that the edge of the anion exchange membrane exceeds the edge of the porous electrode 9, place another sealing gasket 3 on the anion exchange membrane, and insert the porous anode electrode into the gasket groove. Finally, insert the anode terminal plate 1-2 with the anode flow field module 2-2, and tighten the bolts with the insulating gasket. The schematic diagram after installation is as follows: Figure 5-Figure 7 shown.

[0058] After the electrolytic cell is installed, a sealing test is first performed to ensure that the electrolytic cell is sealed and clamped before electrolysis. The electrolyte flows in from the plate inlet holes 14 at the bottom of both sides and is connected to a regulated DC power supply. The electrolysis voltage range is 1.8-2.5V. On the cathode side, 10-100cc / min of electrolyte can be used to enter the cathode porous electrode along the cathode flow field module 2-1, and an electrochemical hydrogen evolution reaction occurs with the electrode. At the same time, the electrolyte also plays a role in gas-liquid exchange. The generated hydrogen bubbles are discharged from the plate outlet holes 15 above the same side of the plate along with part of the electrolyte; on the anode side, the electrolyte of the same flow rate undergoes an electrochemical oxygen evolution reaction from the flow field module 2 with the anode porous electrode, and the generated oxygen bubbles are discharged from the anode side plate outlet holes 15 along with the electrolyte.

[0059] Example 2

[0060] This embodiment is basically the same as the embodiment 1, except that the electrolyzer described in this embodiment is a proton exchange membrane electrolyzer, wherein the electrolyte is pure water, the membrane is a proton exchange membrane, a thin layer of catalyst is coated on both sides of the proton exchange membrane and fixed by hot pressing to form a membrane electrode structure, and the original porous electrode is replaced by titanium felt, so as to achieve working conditions suitable for pure water electrolysis.

[0061] In order to prove the creativity and technical value of the technical solution of the present invention, this section provides application examples of the claimed technical solution on specific products or related technologies.

[0062] Application Example 1

[0063] The technical solution of the present invention can be used in industrial green hydrogen production systems, which utilize renewable energy to generate electricity or waste electricity to perform large-scale water electrolysis to produce hydrogen. The water electrolysis device is combined with a gas-liquid separation device, a washing device, a pressure regulating hydrogen storage device, an electrolyte filtration and circulation device, etc. to form a complete water electrolysis hydrogen production system. By connecting multiple electrolyzers in series, 100Nm 3 / h or more, and even achieve megawatt-level commercial specifications. Compared with traditional alkaline water electrolysis systems, this industrial green hydrogen production system can reduce energy consumption and effectively reduce operation and maintenance costs due to its easy disassembly and assembly.

[0064] Application Example 2

[0065] The technical solution of the present invention can be used for the core research equipment of small-scale hydrogen production experiments, and used as an electrolyzer fixture. Using the electrolyzer fixture proposed by the present invention, in conjunction with an electrochemical workstation, a peristaltic pump, an electric heater, etc., the experimental schemes that can be realized include but are not limited to: porous foam electrode performance test, mesh electrode performance test, flow field optimization performance test, membrane-electrode structure performance test, electrolyzer operation parameter test, etc. The electrolyzer is used as an experimental fixture, and its structure is simple, the assembly difficulty is low, and the service life is long. It can realize and support the research of alkaline water electrolysis technology and proton exchange membrane water electrolysis technology with high precision, and provide equipment support for my country's experiments in the field of water electrolysis technology.

[0066] Application Example 3

[0067] The technical solution of the present invention can be used for hydrogen production equipment for high-altitude detection missions of meteorological stations. Its small size, compact structure, and high hydrogen production efficiency can be used as the core component of the automatic water electrolysis hydrogen production system, and can complete one-button hydrogen production, gas purity analysis, tank hydrogen filling, etc. in an automatic control manner. The system can effectively solve many difficulties encountered by sounding business personnel in hydrogen production, greatly reduce the labor intensity of business personnel, effectively improve the efficiency of hydrogen production, and improve the safety of hydrogen production and use.

[0068] Application Example 4

[0069] The technical solution of the present invention can be applied to medical hydrogen / oxygen absorbers. The small electrolytic cell fixture is combined with the electrolysis technology of the proton exchange membrane. The pure water is electrolyzed to obtain 99.9% pure hydrogen and 99.9% pure oxygen. No harmful impurities are generated during the process, which meets the needs of medical oxygen and emerging hydrogen medicine. Due to its small size and low power consumption, the noise during the actual water electrolysis process is much lower than that of the traditional molecular sieve oxygen generator, so it can be used as a small home medical device.

[0070] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0071] The embodiments of the present invention have achieved some positive effects during the development or use process, and indeed have great advantages over the prior art. The following content is described in conjunction with data, charts, etc. of the test process.

[0072] Multi-physics simulation was performed on the water electrolysis and flow mass transfer process of the single channel of the temperature flow enhancement module of the present invention and the traditional water electrolysis flow channel with the same cross-sectional area. The voltage-current density relationship curve and the outlet hydrogen flux under the operating conditions of the simulated temperature of 70 degrees Celsius, the electrolyte of 30%wt KOH solution, and the inlet normal velocity of 0.1m / s were shown. The simulation results are shown in Figure 8 As shown, the current density determines the electrolysis efficiency. The higher the current density, the faster the water electrolysis rate. Figure 8 (a) It can be seen that the electrolytic performance of the electrolytic cell using the enhanced flow field is better than that of the electrolytic cell using the traditional flow field. The enhanced flow field using the threaded flow channel can reach 1626mA / cm at an electrolytic voltage of 2.4V. 2 The current density is 4.5% higher than that of the traditional flow field with the same cross-section. This is because the turbulence of the flow field strengthens the mass transfer inside the electrode, and the electrolyte flowing along the flow channel rotation can remove the generated bubbles in time, reduce bubble coverage and reduce internal resistance, and the threaded surface inside the flow channel will increase the contact area between the inner side of the flow channel and the electrode surface to a certain extent, thereby improving the electronic conductivity.

[0073] In terms of hydrogen yield, since the hydrogen bubbles generated by water electrolysis can be discharged in time and benefit from the increase in current density caused by turbulence enhancement, this synergistic effect significantly improves the hydrogen yield. Figure 8 As can be seen in (b), as the voltage increases, the outlet hydrogen flux continues to increase, and the advantage of the high hydrogen flux of the turbulence enhancement module of the present invention is more obvious. When the voltage is 2.4V, the hydrogen production is increased by 7.3% compared with the traditional flow field.

[0074] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A water electrolysis hydrogen production device with a turbulence enhancement module, characterized in that: The water electrolysis hydrogen production device with a turbulence enhancement module comprises: The terminal voltage plate includes a cathode terminal voltage plate and an anode terminal voltage plate, which are respectively arranged at the outermost sides of the cathode and the anode, and are used for conducting electricity, fixing and clamping the entire electrolysis device. A square groove for placing a flow field module is provided in the center of the inner side of the terminal voltage plate; The flow field module, including the cathode flow field module and the anode flow field module, is a square plate structure, one side is smooth, and the other side is provided with a serpentine thread flow channel, and the beginning and end of the serpentine thread flow channel are respectively provided with vertical inlet and outlet holes, and the inlet and outlet holes correspond to the liquid inlet and gas outlet of the end pressure plate; Metal electrodes, including metal cathodes and metal anodes, are porous electrodes; The diaphragm is located between the cathode terminal plate and the anode terminal plate; A sealing gasket groove is provided around the square groove of the end voltage plate, and a sealing gasket for sealing the entire device is installed in the sealing gasket groove; An insulating thickness limiting plate is arranged between the cathode flow field module and the anode flow field module to prevent the cathode terminal voltage plate and the anode terminal voltage plate from being too close to cause a short circuit, and to prevent excessive force applied during clamping from damaging the membrane and the metal electrode structure.

2. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: A copper connection copper plate is installed on the outer side of the end voltage plate for loading external current; holes with the same intervals are arranged on the outer periphery of the end voltage plate for bolt fastening.

3. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: The metal electrode is a foam metal electrode, a woven mesh or an expanded mesh metal, and the thickness of the metal electrode is 0.1-2 mm.

4. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: The sealing gasket is a silicone gasket, and the thickness of the sealing gasket is 0.8 mm thicker than that of the metal electrode.

5. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: The insulating thickness limiting plate is made of epoxy resin plate, and its thickness is the sum of the thickness of the selected metal cathode and the metal anode.

6. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: The diaphragm is an anion exchange membrane or a proton exchange membrane, and the area of ​​the diaphragm is larger than the area of ​​the metal electrode and does not exceed the outer circle of the sealing gasket.

7. The water electrolysis hydrogen production device with a turbulence enhancement module according to claim 1, characterized in that: The square groove of the end pressure plate is provided with a plate liquid inlet hole and a plate gas outlet hole diagonally distributed therein, and runs through the entire end pressure plate.

8. A method for producing hydrogen by electrolysis of water for implementing the water electrolysis hydrogen production device with a turbulence enhancement module as claimed in any one of claims 1 to 7, characterized in that: The method for producing hydrogen by electrolysis of water comprises: Step 1: After installing the electrolytic cell, first conduct a sealing test to ensure that the electrolytic cell is tightly sealed before conducting electrolysis; Step 2: The electrolyte flows into the plate from the liquid inlet holes at the bottom of both sides and is connected to a regulated DC power supply with an electrolysis voltage range of 1.8-2.5V; Step 3: On the cathode side, an electrolyte at a flow rate of 10-100 cc / min is introduced into the cathode porous electrode along the cathode flow field module to generate an electrochemical hydrogen evolution reaction with the electrode. At the same time, the electrolyte also plays a role in gas-liquid exchange. The generated hydrogen bubbles are discharged from the plate outlet holes on the same side of the end pressure plate along with part of the electrolyte. Step 4: On the anode side, the electrolyte with the same flow rate undergoes an electrochemical oxygen evolution reaction with the anode porous electrode through the flow field module, and the generated oxygen bubbles are discharged from the anode side plate outlet along with the electrolyte.

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