An anion exchange membrane electrolysis system and method for hydrogen and oxygen production in high-altitude areas

Abstract

This application relates to the field of hydrogen and oxygen production through water electrolysis, and discloses a system and method for hydrogen and oxygen production through anion exchange membrane electrolysis of water in high-altitude environments. The system includes a liquid supply unit, an electrolyzer unit, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. The liquid supply unit is connected to the electrolyzer unit, which is also connected to the gas-liquid separation and purification unit. The condensate produced by the gas-liquid separation and purification unit is returned to the liquid supply unit. The pressure balance control unit is connected to both the hydrogen and oxygen sides within the gas-liquid separation and purification unit. The central control and coordination unit is connected to the electrolyzer unit. This system solves the technical problem of achieving long-term, high-efficiency, safe hydrogen supply, and stable oxygen supply in anion exchange membrane water electrolysis system under low-pressure conditions in high-altitude environments. Furthermore, it significantly improves system reliability and environmental adaptability, and meets the dual requirements of hydrogen and oxygen co-production in special scenarios.

Description

Technical Field

[0001] This application relates to the field of hydrogen production by water electrolysis, and in particular to an anion exchange membrane water electrolysis system and method for hydrogen and oxygen production in high-altitude areas. Background Technology

[0002] Anion exchange membrane water electrolysis (AEMWE) stands out among many hydrogen production methods due to its advantages such as the ability to use non-precious metal catalysts and lower cost.

[0003] However, the unique characteristics of the high-altitude environment make conventional anion exchange membrane water electrolysis systems unsuitable for direct application. Related technologies employ differential pressure designs, but controlling this differential pressure faces severe challenges in the low-pressure environment of high altitudes, directly exacerbating the "hydrogen in oxygen" problem. Specifically, under low pressure, maintaining a sufficient differential pressure may lead to a relatively high pressure on the cathode side, creating a pressure gradient pointing towards the anode (oxygen side). This gradient significantly intensifies the permeation, diffusion, and even leakage of hydrogen through the membrane electrode or sealing gaps, resulting in an abnormally high hydrogen concentration in the oxygen product. This phenomenon will trigger systemic risks: firstly, the purity of the oxygen product will decrease significantly due to hydrogen contamination; secondly, fluctuations in hydrogen concentration will interfere with the stable operation of the electrolyzer, forcing frequent system adjustments or protective shutdowns, leading to intermittent interruptions or drastic fluctuations in oxygen supply; most critically, the high-concentration hydrogen-oxygen mixture formed in the produced gas greatly increases the risk of explosion, keeping the system in a constantly high-risk state.

[0004] Therefore, the technical challenge of achieving long-term high efficiency, ensuring hydrogen safety, and providing stable oxygen supply in anion exchange membrane water electrolysis systems in high-altitude areas has become a key research focus. Summary of the Invention

[0005] This application provides an anion exchange membrane electrolysis water electrolysis system and method for hydrogen and oxygen production in high-altitude environments. It addresses the technical challenge of achieving long-term, safe, efficient, and structurally simplified operation of anion exchange membrane water electrolysis systems in low-pressure environments at high altitudes. This effectively protects the anion exchange membrane from pressure differential damage, significantly improves system reliability and environmental adaptability, reduces the residual hydrogen content in the anode oxygen (the "hydrogen in oxygen" problem), and enhances product purity and safety. Ultimately, the system achieves efficient co-production of high-purity hydrogen and oxygen, stably and synergistically meeting the dual demands of downstream applications for both gases. The main technical solutions adopted in this application include: This application provides a hydrogen and oxygen production system for anion exchange membrane electrolysis of water in high-altitude areas. The system includes a liquid supply unit, an electrolyzer unit, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. The liquid supply unit is connected to the electrolyzer unit, and the electrolyzer unit is connected to the gas-liquid separation and purification unit. The liquid reflux port of the gas-liquid separation and purification unit is connected to the liquid supply unit. The pressure control unit is connected to both the hydrogen and oxygen sides within the gas-liquid separation and purification unit. The central control and coordination unit is connected to the electrolyzer unit. Wherein: The liquid supply unit is used to obtain an alkaline solution with a concentration and temperature that meet preset standards, and supplies the alkaline solution to the cathode of the electrolytic cell unit through a single cathode liquid supply method, and recovers the condensate generated by the gas-liquid separation and purification unit. The electrolytic cell unit is used to electrolyze the alkaline solution from the liquid supply unit to generate hydrogen at the cathode and oxygen at the anode, and to supply the generated gas to the gas-liquid separation and purification unit. The hydrogen side of the gas-liquid separation and purification unit is used to separate and purify the hydrogen generated by the cathode, and the oxygen side of the gas-liquid separation and purification unit is used to separate and purify the oxygen generated by the anode. The condensate generated during the separation and purification process is returned to the liquid supply unit. The pressure control unit is used to control the pressure on the hydrogen side and the oxygen side in the gas-liquid separation and purification unit, so that the pressure difference between the hydrogen side and the oxygen side is maintained within a set range. The central control and coordination unit is used to provide DC power to the electrolytic cell unit and integrates a central controller; the central controller is communicatively connected to each unit to automatically operate and control the system.

[0006] This embodiment provides an anion exchange membrane electrolysis water electrolysis hydrogen and oxygen production system for high-altitude areas. The system comprises a liquid supply unit, an electrolyzer unit, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. Through real-time monitoring and dynamic adjustment of the pressure control unit connected to both the hydrogen and oxygen sides, the system maintains a high-pressure state at both the cathode and anode while dynamically controlling the pressure difference between them within a set reasonable range. This ensures a safe system, preventing irreversible mechanical damage to the anion exchange membrane caused by the pressure difference between the hydrogen and oxygen sides. Furthermore, the pressure difference regulation effectively reduces the hydrogen content in the oxygen, resolving the safety hazards caused by hydrogen-oxygen mixing in the low-pressure environment of high-altitude areas. This invention employs a single-cathode liquid supply design, simplifying the complex anode circulation loop of conventional dual-electrode liquid supply systems, thereby achieving efficient system operation. The entire process is integrated and controlled by a central controller, realizing fully automated intelligent control from startup, operation, maintenance to shutdown. This not only significantly improves the reliability and environmental adaptability of hydrogen production by anion exchange membrane water electrolysis, but also meets the dual needs of clean energy and stable oxygen source in special scenarios such as high altitude and medical settings through hydrogen-oxygen co-production, greatly enhancing the comprehensive application value of the system.

[0007] In one embodiment, the pressure control unit includes a pressure sensor, a pressure balancing valve, and a pipeline, wherein the pipeline connects the hydrogen side and the oxygen side of the gas-liquid separation and purification unit, and the pressure sensor and the pressure balancing valve are mounted on the pipeline; wherein: The pressure sensor is used to feed back pressure signals from the hydrogen side and the oxygen side to the central control and coordination unit. The central controller in the central control and coordination unit adjusts the opening of the pressure balancing valve according to the pressure signals to control the pressure difference between the hydrogen side and the oxygen side within a preset pressure difference range.

[0008] This embodiment utilizes a pressure control unit comprising a pressure sensor, a pressure balancing valve, and piping. The piping connects the hydrogen and oxygen sides of the gas-liquid separation and purification unit, and is equipped with both the pressure sensor and the pressure balancing valve. The pressure sensor feeds back pressure signals from the hydrogen and oxygen sides to the central controller in the central control and coordination unit. The central control and coordination unit adjusts the opening of the pressure balancing valve based on the pressure signals to maintain the pressure difference between the hydrogen and oxygen sides within a preset range. The pressure sensor can be a piezoresistive sensor, a capacitive sensor, or other pressure sensing element, used to feed back pressure signals to the central controller in the central control and coordination unit. The pressure balancing valve can be a pressure reducing valve, an overflow valve, or other pressure control valve, used to receive signals from the central controller and dynamically adjust the valve opening to achieve pressure control, thereby maintaining the pressure balance between the hydrogen and oxygen sides in the gas-liquid separation and purification unit.

[0009] In one embodiment, the hydrogen-side and oxygen-side ends of the gas-liquid separation and purification unit are equipped with a hydrogen-side back pressure valve and an oxygen-side back pressure valve, wherein: The central control and coordination unit is specifically used to coordinate and control the hydrogen-side back pressure valve, the oxygen-side back pressure valve, and the pressure control unit to adjust the pressure difference between the hydrogen side and the oxygen side.

[0010] This embodiment uses hydrogen-side and oxygen-side back pressure valves, which are communicatively connected to the central control and coordination unit, to enable real-time monitoring and precise adjustment of the system's pressure balance determination results. Specifically, when the central controller detects that the absolute value of the pressure difference between the hydrogen and oxygen sides exceeds a preset safety threshold, the controller adjusts the opening of the pressure balancing valve and / or fine-tunes the opening of the hydrogen-side and oxygen-side back pressure valves to restore pressure balance on both sides. The system design is specifically tailored for high-altitude, low-pressure environments, exhibiting strong pressure balancing capabilities and high reliability.

[0011] In one embodiment, the liquid supply unit includes an alkali buffer tank, and a first branch, a second branch, and a third branch connected to the alkali buffer tank, wherein: The first branch is used to supply deionized water to the alkaline buffer tank; The second branch is used to supply alkaline solution to the alkaline buffer tank; The alkaline buffer tank is used to mix the deionized water and the alkaline solution, and to adjust the concentration of the mixed alkaline solution. The third branch is used to adjust the temperature of the alkaline solution output from the alkaline solution buffer tank to obtain an alkaline solution with a concentration and temperature that meet the preset standards, and to supply the alkaline solution with a concentration and temperature that meet the preset standards to the cathode of the electrolytic cell unit through a single cathode supply method.

[0012] This embodiment solves the problem of the impossibility of single-cathode electrolyte supply by setting up a first branch, a second branch, a third branch, and an alkali buffer tank. During long-term electrolysis, a large amount of water is consumed, leading to an increase in the alkali concentration in the electrolyzer. Simultaneously, the increased concentration due to long-term operation causes an increase in hydroxide ion concentration on the surface and adjacent areas of the anion exchange membrane on the cathode side, thereby accelerating the chemical degradation of the membrane and potentially leading to functional failure. At the same time, the viscosity of the alkali increases accordingly. High-viscosity concentrated alkali hinders the transport of reactants (water) and products (oxygen bubbles and hydrogen bubbles), exacerbating concentration polarization. To maintain the required current density, the cell voltage must be increased, resulting in reduced system efficiency. Furthermore, increased viscosity also leads to an increase in gas evolution overpotential. In a viscous electrolyte, oxygen and hydrogen bubbles are more difficult to detach from the electrode surface, covering and reducing effective reactive sites, further reducing electrolysis efficiency. By communicating with the central control and coordination unit to control the electrolyte supply unit, the supply unit can automatically provide the optimal reaction environment to the electrolyzer unit in real time, achieving single-cathode electrolyte supply. The single-cathode liquid supply unit eliminates the complex anode-side circulation loop of the bipolar liquid supply unit, simplifying the system structure. This technical solution improves system stability, automation, and structural simplification.

[0013] In one embodiment, the first branch includes a water replenishment pump, a purification device, and a deionization device connected in sequence; the second branch includes an alkali addition device.

[0014] This embodiment prevents impurity ions from participating in side reactions or forming scale on the electrodes and membrane surfaces during electrolysis by incorporating a deionization device, ensuring efficient water electrolysis. When the central controller detects that the alkali concentration in the electrolyzer unit is too high, water produced by the deionization device is used to dilute the alkali in the buffer tank via the first branch, thereby precisely controlling the alkali concentration in the electrolyzer unit within the optimal range. High-purity water prevents impurity ions (such as heavy metal ions) from contaminating and damaging the membrane structure. Using deionized water minimizes voltage increases (increased energy consumption) caused by scaling and contamination, maintaining high system efficiency. This technical solution avoids problems such as localized corrosion and decreased gas purity caused by impurities, ensuring long-term system stability and the quality of the produced gas.

[0015] In one embodiment, the third branch includes a circulating pump, a heat exchanger, and a flow regulating valve, wherein the heat exchanger is used to control the temperature of the alkali solution output by the circulating pump.

[0016] In one embodiment, the alkali buffer tank is further equipped with a concentration sensor, wherein the concentration sensor is used to detect the concentration of alkali in the alkali buffer tank; the central control and coordination unit controls the execution of dilution or replenishment of the alkali based on the detection result; the alkali buffer tank is also used to recover the condensate separated by the gas-liquid separation and purification unit.

[0017] This embodiment utilizes a heat exchanger to enable more precise temperature control of the electrolysis reaction. Specifically, the Joule heat generated by the water electrolysis reaction significantly exacerbates the impact of hydroxide ions on the membrane polymer backbone and quaternary ammonium groups under strongly alkaline conditions, leading to decreased membrane conductivity and loss of mechanical strength. The constant-temperature operation of the electrolysis reaction within the electrolyzer unit is achieved through automated control by a central controller.

[0018] A second aspect of this application provides a method for producing hydrogen and oxygen through anion exchange membrane electrolysis of water in high-altitude areas, the method comprising: The alkaline solution with a concentration and temperature that meet the preset standards is obtained through the liquid supply unit, and the alkaline solution is supplied to the cathode of the electrolytic cell unit through a single cathode liquid supply method, and the condensate generated by the gas-liquid separation and purification unit is recovered. The alkaline solution from the supply unit is electrolyzed through the electrolytic cell unit to generate hydrogen at the cathode and oxygen at the anode, and the generated gas is provided to the gas-liquid separation and purification unit. The hydrogen generated at the cathode is separated and purified through the hydrogen side of the gas-liquid separation and purification unit, and the oxygen generated at the anode is separated and purified through the oxygen side of the gas-liquid separation and purification unit. The condensate generated during the separation and purification process is returned to the liquid supply unit. The pressure control unit controls the pressure on the hydrogen and oxygen sides of the gas-liquid separation and purification unit, so that the pressure difference between the hydrogen and oxygen sides is maintained within a set range. The central control and coordination unit provides DC power to the electrolytic cell unit. The central control and coordination unit integrates a central controller, which communicates with each unit to automatically operate and control the system. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1A schematic diagram of the system described in this invention. In the diagram: 1-Electrolytic cell unit; 2-First branch of the liquid supply unit; 21-Water replenishment pump device; 22-Impurity removal device; 23-Deionization device; 3-Second branch of the liquid supply unit; 31-Alkali addition device; 4-Alkali buffer tank; 41-Concentration sensor; 5-Third branch of the liquid supply unit; 51-Circulation pump; 52-Heat exchanger; 53-Flow regulating valve; 6-Hydrogen-side gas-liquid separation and purification unit: 61-Hydrogen-side gas-liquid separator; 62-Hydrogen-side condenser; 63-Hydrogen-side dryer; 64-Hydrogen-side safety detector; 65-Catalytic deoxygenation device; 66-Hydrogen-side gas-liquid separation and purification unit. 6-Regeneration bed dryer; 67-Hydrogen-side gas purity analyzer; 68-Hydrogen-side back pressure valve; 7-Oxygen-side gas-liquid separation and purification unit; 71-Oxygen-side gas-liquid separator; 72-Oxygen-side condenser; 73-Alkali mist removal device; 74-Catalytic deodorization device; 75-Oxygen-side dryer; 76-Oxygen-side gas purity analyzer; 77-Oxygen-side back pressure valve; 8-Pressure control unit; 81-Pressure sensor; 82-Pressure balancing valve; 83-Pipeline; 9-Central control and coordination unit; 91-High voltage AC power; 92-Transformer; 93-Rectifier.

[0021] Figure 2 This application provides a step diagram of a method for producing hydrogen and oxygen through anion exchange membrane electrolysis of water, specifically for high-altitude applications, as one embodiment of the present application. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] Anion exchange membrane water electrolysis (AEMWE) technology has stood out among many hydrogen production methods due to its advantages such as the ability to use non-precious metal catalysts and lower cost. However, it is difficult to maintain a precise pressure balance between the cathode and anode during operation. Pressure fluctuations or excessive pressure differences can cause irreversible mechanical damage to the anion exchange membrane.

[0024] When the aforementioned system is applied to high-altitude, low-pressure environments, its drawbacks are further exacerbated. The reduced external environmental pressure makes internal pressure balance control more complex, and the absolute pressure baseline within the system decreases in such environments. Even minor internal pressure fluctuations in plains areas (e.g., due to slight changes in the electrolysis reaction rate or minor pump pulsations) increase the relative pressure difference between the anode and cathode, creating potentially threatening mechanical stresses on both sides of the ion exchange membrane, significantly increasing the risk of mechanical damage to the anion exchange membrane. In differential pressure electrolysis systems employing related technologies, the hydrogen side pressure is higher than the oxygen side, making it highly susceptible to hydrogen permeation into the oxygen side. As the pressure difference between the anode and cathode increases, hydrogen is more easily transported across the anion exchange membrane to the oxygen side under pressure, leading to an increase in hydrogen content in the oxygen. Furthermore, to maintain a large pressure difference between the anode and cathode for efficient hydrogen production, the oxygen produced at the anode is treated as waste gas and directly discharged. This not only wastes scarce resources in high-altitude areas but also poses a safety hazard when exposed to open flames during discharge, as the issue of hydrogen in the oxygen remains unresolved, affecting the safe operation of the equipment. The oxygen supplied by dual-electrode or single-anode systems often contains a large amount of alkaline solution, reducing oxygen purity and complicating separation and purification. Differential pressure systems (cathode pressurized, anode at atmospheric pressure) suffer membrane damage and hydrogen contamination issues. Furthermore, the low atmospheric pressure at high altitudes makes gas desorption difficult, increasing energy consumption and impacting system safety, leading to membrane damage and reduced energy efficiency. Conversely, differential pressure systems, which prioritize hydrogen output pressure, sacrifice membrane safety and gas purity. This contradiction is particularly acute in high-altitude, low-pressure environments.

[0025] This application provides one or more embodiments of anion exchange membrane electrolysis water production hydrogen and oxygen system and method for high-altitude applications. These methods effectively protect the anion exchange membrane from pressure differential damage, significantly improve system reliability and environmental adaptability, reduce the residual hydrogen content in the anode oxygen, and enhance product purity and safety. Ultimately, the system achieves efficient co-production of high-purity hydrogen and oxygen, stably and synergistically meeting the dual requirements of downstream applications for both gases.

[0026] Please see Figure 1 In one aspect, this application provides an anion exchange membrane electrolysis water production system for high-altitude areas to generate hydrogen and oxygen. The system includes a liquid supply unit, an electrolyzer unit 1, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. The liquid supply unit is connected to the electrolyzer unit 1, and the electrolyzer unit 1 is connected to the gas-liquid separation and purification unit. The liquid return port of the gas-liquid separation and purification unit is connected to the liquid supply unit. The pressure control unit is connected to both the hydrogen and oxygen sides within the gas-liquid separation and purification unit. The central control and coordination unit is connected to the electrolyzer unit 1. Wherein: The liquid supply unit is used to obtain alkaline solution with a concentration and temperature that meet the preset standards, and supplies alkaline solution to the cathode of electrolytic cell unit 1 through a single cathode liquid supply method, and recovers the condensate generated by the gas-liquid separation and purification unit.

[0027] Electrolytic cell unit 1 is used to electrolyze the alkaline solution from the liquid supply unit to generate hydrogen at the cathode and oxygen at the anode, and to supply the generated gas to the gas-liquid separation and purification unit.

[0028] The hydrogen side of the gas-liquid separation and purification unit is used to separate and purify the hydrogen generated at the cathode, and the oxygen side of the gas-liquid separation and purification unit is used to separate and purify the oxygen generated at the anode. The condensate generated during the separation and purification process is returned to the liquid supply unit.

[0029] The pressure control unit is used to control the pressure on the hydrogen side and the oxygen side in the gas-liquid separation and purification unit, so that the pressure difference between the hydrogen side and the oxygen side is maintained within a set range.

[0030] The central control and coordination unit is used to provide DC power to the electrolytic cell unit 1 and integrates a central controller; the central controller is connected to each unit for automatic operation and control of the system.

[0031] In this embodiment, the electrolyte supply unit is directly connected to the cathode of the electrolytic cell. Its core function is to maintain a stable electrochemical reaction environment by precisely controlling the electrolyte parameters: on the one hand, by controlling the electrolyte concentration, it avoids the depletion of hydroxide ions on the electrode surface due to long-term operation, thereby preventing concentration polarization; on the other hand, by adjusting the electrolyte temperature, it effectively neutralizes the Joule heat generated during the electrolysis process, preventing local overheating of the system.

[0032] In this embodiment, electrolytic cell unit 1 serves as the reaction core, internally equipped with an anion exchange membrane, dividing the unit into a cathode chamber and an anode chamber. This unit is used to electrolyze the alkaline electrolyte from the supply unit; water molecules undergo a reduction reaction at the cathode, generating hydrogen gas and hydroxide ions; subsequently, the hydroxide ions migrate through the anion exchange membrane to the anode under the drive of the electric field, where they undergo an oxidation reaction, ultimately generating oxygen and water. During this process, the alkaline electrolyte primarily functions to maintain ion conduction and stabilize the reaction interface.

[0033] In this embodiment, the gas-liquid separation and purification unit is the collection and purification section, which includes a hydrogen side and an oxygen side. The hydrogen-side gas-liquid separation and purification unit is sequentially connected to a hydrogen-side gas-liquid separator 61, a hydrogen-side condenser 62, a hydrogen-side dryer 63, a hydrogen-hydrogen side safety detector 64, a catalytic deoxygenation device 65, a regeneration bed dryer 66, a hydrogen-side gas purity analyzer 67, and a hydrogen-side back pressure valve 68. The oxygen-side gas-liquid separation and purification unit includes, sequentially connected to, an oxygen-side gas-liquid separator 71, an oxygen-side condenser 72, an alkaline mist removal device 73, a catalytic deodorization device 74, an oxygen-side dryer 75, an oxygen-side gas purity analyzer 76, and an oxygen-side back pressure valve 77. The entire gas-liquid separation and purification unit, through the above two parallel and independent subsystems, ultimately outputs high-purity, low-dew-point dry hydrogen and dry oxygen, which not only meets the gas quality requirements for subsequent storage or use, but also ensures the safety and stability of the entire process through safety detection and pressure regulation.

[0034] In this embodiment, the pressure control unit is used to regulate the high-pressure environment added to accelerate the hydrogen evolution reaction at the cathode. The system is maintained at an operating pressure higher than ambient atmospheric pressure. Maintaining a higher operating pressure has clear engineering benefits: firstly, it allows for the direct generation of high-pressure hydrogen and oxygen, significantly reducing the energy consumption of subsequent gas compression processes; secondly, the higher pressure significantly reduces gas volume, which is beneficial for improving the separation efficiency of the gas-liquid mixture in the separator. However, continuous high pressure on the cathode side can easily lead to irreversible mechanical damage to the anion exchange membrane. Therefore, the pressure control unit adjusts the pressure difference between the two sides to maintain the pressure difference between the hydrogen and oxygen sides within a set range under high-pressure conditions, protecting the membrane material and maintaining stable system operation. By maintaining a stable low pressure difference, the permeation of hydrogen to the oxygen side can be effectively suppressed, thereby significantly reducing the hydrogen content in the oxygen product and achieving the collection of high-purity oxygen.

[0035] In this embodiment, the central control and coordination unit typically includes a transformer 92, a rectifier 93, and a central controller. The transformer 92 and rectifier 93 are used to supply power to the electrolytic cell unit 1. The central controller integrates and controls all pumps, valves, power supplies, and sensors through a communication link, and displays the received real-time data on a display screen, thus realizing full automation from startup, operation, maintenance to safe shutdown.

[0036] Based on the above ideas, the technical solution provided in this embodiment of the application constructs an anion exchange membrane water electrolysis hydrogen production system, consisting of a liquid supply unit, an electrolyzer unit 1, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. This system, through real-time monitoring and dynamic adjustment by the pressure control unit connected to both the hydrogen and oxygen sides, ensures that the pressure difference between the anode and cathode chambers remains within a certain range, for example, less than 1 MPa, under any operating condition, to avoid membrane damage. This constitutes a safe system, preventing irreversible mechanical damage to the anion exchange membrane caused by the pressure difference between the hydrogen and oxygen sides. Simultaneously, the pressure difference regulation reduces the hydrogen content in the oxygen, solving the safety hazards caused by hydrogen-oxygen mixing in low-pressure environments at high altitudes. Furthermore, the single-cathode liquid supply design eliminates the complex anode circulation loop, significantly simplifying the system structure. The entire process is integrated and controlled by a central controller, realizing fully automated intelligent control from startup, operation, maintenance to shutdown. This not only significantly improves the reliability and environmental adaptability of hydrogen production by anion exchange membrane water electrolysis, but also meets the dual needs of clean energy and stable oxygen source in special scenarios such as high altitude and medical settings through hydrogen-oxygen co-production, greatly enhancing the comprehensive application value of the system.

[0037] In one embodiment, the pressure control unit includes a pressure sensor 81, a pressure balancing valve 82, and a pipeline 83. The pipeline 83 connects the hydrogen and oxygen sides of the gas-liquid separation and purification unit. The pressure sensor 81 and pressure balancing valve 82 are mounted on the pipeline 83. The pressure sensor 81 feeds back pressure signals from the hydrogen and oxygen sides to the central controller unit in the central control and coordination unit. The central control and coordination unit adjusts the opening of the pressure balancing valve 82 based on the pressure signals to control the pressure difference between the hydrogen and oxygen sides within a preset range. The pressure sensor 81 can be a piezoresistive sensor, a capacitive sensor, or other pressure sensing element, used to feed back pressure signals to the central controller unit. The pressure balancing valve 82 can be a pressure reducing valve, an overflow valve, or other pressure control valve, used to receive signals from the central controller and dynamically adjust the valve opening to achieve pressure control, thereby maintaining the pressure balance between the hydrogen and oxygen sides in the gas-liquid separation and purification unit.

[0038] The technical solution provided in this embodiment enables the system to monitor and precisely adjust the pressure balance determination result in real time by setting a pressure sensor 81 and a pressure balancing valve 82 that are communicatively connected to the central control and coordination unit. Specifically, the central controller of the central control and coordination unit receives the pressure signals from the hydrogen and oxygen sides of the pressure sensor 81 in real time and displays them on the panel of the central controller. The central controller controls the opening of the dynamically adjusting valve to achieve pressure regulation. This technical solution improves the system's automation, accuracy, and visualization.

[0039] In one embodiment, the hydrogen-side and oxygen-side ends of the gas-liquid separation and purification unit are equipped with a hydrogen-side back pressure valve 68 and an oxygen-side back pressure valve 77. Specifically, the central control and coordination unit is used to coordinate and control the hydrogen-side back pressure valve 68, the oxygen-side back pressure valve 77, and the pressure control unit to regulate the pressure difference between the hydrogen-side and oxygen-side. The back pressure valve can be a pressure reducing valve, an overflow valve, or other pressure control valve, and is used to control the gas output rate.

[0040] The technical solution provided in this embodiment enables real-time monitoring and precise adjustment of the system pressure balance determination results by setting up a hydrogen-side back pressure valve 68 and an oxygen-side back pressure valve 77 that are communicatively connected to the central control and coordination unit. Specifically, when the central controller detects that the absolute value of the pressure difference between the hydrogen and oxygen sides exceeds a preset safety threshold, the controller adjusts the opening of the pressure balancing valve 82 and / or fine-tunes the opening of the hydrogen-side back pressure valve 68 and the oxygen-side back pressure valve 77 to restore the pressure balance on both sides. The system design is specifically tailored for high-altitude, low-pressure environments, exhibiting strong pressure balancing capabilities and high reliability.

[0041] In one embodiment, the liquid supply unit includes an alkali buffer tank 4, and a first branch, a second branch, and a third branch connected to the alkali buffer tank 4. The first branch is used to supply deionized water to the alkali buffer tank 4; the second branch is used to supply an alkaline solution to the alkali buffer tank 4; the alkali buffer tank 4 is used to mix the deionized water and the alkaline solution and adjust the concentration of the mixed alkali solution; the third branch is used to adjust the temperature of the alkali solution output from the alkali buffer tank 4 to obtain an alkali solution with a concentration and temperature that meet a preset standard, and to supply the alkali solution with a concentration and temperature that meet the preset standard to the cathode of the electrolytic cell unit 1 through a single cathode liquid supply method. The central control and coordination unit communicates with the first branch, the second branch, the third branch, and the alkali buffer tank 4 to regulate the concentration and temperature of the alkali solution supplied to the cathode of the electrolytic cell unit 1 by the third branch. Specifically, when the central controller detects that the concentration of the alkali solution in the electrolytic cell unit 1 is higher than the set value, the central controller controls the first branch to add deionized water to the alkali buffer tank 4 to dilute the alkali solution in the tank. The diluted alkali solution is then supplied to the electrolytic cell unit 1 through the third branch. When the central controller detects that the concentration of the alkali solution in the electrolytic cell unit 1 is lower than the set lower limit, the central controller controls the second branch to add concentrated alkali solution to the alkali buffer tank 4. The mixed alkali solution is then supplied to the electrolytic cell unit 1 through the third branch. When the central controller detects that the temperature of the electrolytic cell unit 1 is higher than the set upper limit, the central controller controls the third branch to supply low-temperature alkali solution to the electrolytic cell unit 1. When the central controller detects that the temperature of the electrolytic cell unit 1 is lower than the set lower limit, the central controller controls the third branch to supply high-temperature alkali solution to the electrolytic cell unit 1.

[0042] The technical solution provided in this embodiment solves the problem of the impossibility of single-cathode electrolyte supply by setting up a first branch, a second branch, a third branch, and an alkali buffer tank 4. During long-term electrolysis, a large amount of water is consumed, leading to an increase in the concentration of alkali in the electrolytic cell. Simultaneously, the increased concentration due to long-term operation causes an increase in hydroxide ion concentration on the surface and adjacent areas of the anion exchange membrane on the cathode side, thereby accelerating the chemical degradation of the membrane and potentially leading to functional failure. At the same time, the viscosity of the alkali increases accordingly. High-viscosity concentrated alkali hinders the transport of reactants (water) and products (oxygen bubbles and hydrogen bubbles), exacerbating concentration polarization. To maintain the required current density, the cell voltage must be increased, resulting in reduced system efficiency. Furthermore, increased viscosity also leads to an increase in gas evolution overpotential. In a viscous electrolyte, oxygen and hydrogen bubbles are more difficult to detach from the electrode surface, covering and reducing effective reactive sites, further reducing electrolysis efficiency. By communicating with the central control and coordination unit to control the electrolyte supply unit, the supply unit can automatically provide the optimal reaction environment for the electrolytic cell unit 1 in real time, achieving single-cathode electrolyte supply. The single-cathode liquid supply unit eliminates the complex anode-side circulation loop of the bipolar liquid supply unit, simplifying the system structure. This technical solution improves system stability, automation, and structural simplification.

[0043] In one embodiment, the first branch includes a water supply pump device 21, a purification device 22, and a deionization device 23 connected in sequence; the second branch includes an alkali addition device 31. The water supply pump device 21 can be a centrifugal pump, a pressure switch, or other pressure-stabilizing water supply device to maintain system pressure, and is used to pump water. The purification device 22 can be a filter, a centrifuge, or other water treatment equipment to purify water, and is used to remove impurities from the water pumped by the water supply pump device 21. The deionization device 23 can be an ion exchange column, an electrodialysis unit, or other pure water preparation equipment to remove ionic impurities from water, and is used to prepare and provide high-purity water to ensure efficient and stable electrolysis. The alkali addition device 31 is used to provide a high-concentration alkali solution.

[0044] The technical solution provided in this embodiment prevents impurity ions from participating in side reactions or forming scale on the electrode and membrane surfaces during electrolysis by setting up a deionization device 23, ensuring efficient water electrolysis. When the central controller detects that the alkali concentration in electrolytic cell unit 1 is too high, the water produced by the deionization device 23 is used to dilute the alkali in the buffer tank via the first branch, thereby precisely controlling the alkali concentration in the electrolytic cell unit within the optimal range. High-purity water can prevent impurity ions (such as heavy metal ions) from contaminating and damaging the membrane structure. Using deionized water can minimize voltage rise (increased energy consumption) caused by scaling and contamination, maintaining the system at high energy efficiency. This technical solution avoids problems such as localized corrosion and decreased gas purity caused by impurities, ensuring the long-term operational stability of the system and the quality of the produced gas.

[0045] In one embodiment, the third branch includes a circulating pump 51, a heat exchanger 52, and a flow regulating valve 53. The heat exchanger 52 controls the temperature of the alkali solution output by the circulating pump 51. The circulating pump 51 can be a centrifugal pump, a magnetically driven pump, a booster pump, etc. The circulating pump 51 draws liquid from the alkali buffer tank 4 and supplies it to the cathode of the electrolytic cell unit 1. The heat exchanger 52 can be a shell-and-tube heat exchanger, a plate heat exchanger, a coaxial heat exchanger, etc. The heat exchanger 52 is controlled by a central controller, which adjusts the temperature of the liquid drawn by the circulating pump 51 based on the temperature signal fed back from the electrolytic cell unit 1 to maintain the optimal reaction temperature of the electrolytic cell unit 1. The flow regulating valve 53 can be a regulating valve, a control valve, a throttle valve, etc. The flow regulating valve 53 is controlled by the central controller to adjust the rate at which the circulating pump 51 supplies liquid to the cathode.

[0046] The technical solution provided in this embodiment enables the system to more accurately control the temperature of the electrolysis reaction by setting up a heat exchanger 52. Specifically, the Joule heat generated by the water electrolysis reaction greatly aggravates the influence of hydroxide ions on the membrane polymer backbone and quaternary ammonium groups under a strongly alkaline environment, leading to a decrease in membrane conductivity and loss of mechanical strength. The constant temperature operation of the electrolysis reaction in the electrolytic cell unit 1 is achieved through the automated control of the central controller.

[0047] In one embodiment, the alkali buffer tank 4 is further equipped with a concentration sensor 41. The concentration sensor 41 is used to detect the concentration of alkali solution within the alkali buffer tank 4. Based on the detection results, the central control and coordination unit controls the execution of alkali dilution or alkali replenishment operations. The alkali buffer tank 4 is also used to recover the condensate separated by the gas-liquid separation and purification unit. The concentration sensor 41 can be a conductivity meter, optical densitometer, or other online analytical device for detecting the concentration of the target substance. The concentration sensor 41 measures the concentration within the alkali buffer tank 4 and transmits the concentration signal to the central controller. Based on the concentration signal within the alkali buffer tank 4 and real-time concentration information from the electrolytic cell unit 1, the central controller dynamically adjusts the supply of deionized water or replenishing alkali solution into the alkali buffer tank 4 by controlling the valve opening or pump flow rate of the first and second branches, thereby achieving precise control of the alkali concentration. The alkali buffer tank 4 is also connected to the gas-liquid separation and purification unit for recovering the condensate separated by this unit. The recovered condensate can be used as deionized water to participate in the above-mentioned concentration adjustment process, realizing the recycling of water resources.

[0048] The technical solution provided in this embodiment achieves real-time monitoring and automatic control of the alkali concentration by installing a concentration sensor 41 in the alkali buffer tank 4 and linking it with the central controller, thus ensuring the stability of the feed concentration to the electrolyzer. Simultaneously, by recovering the condensate generated during gas-liquid separation and using it for concentration adjustment within the system, not only is resource utilization efficiency improved, but the system's water balance is also maintained, enhancing the overall sustainability and economy of operation.

[0049] In one embodiment, the gas-liquid separation and purification unit is provided with a hydrogen-side gas-liquid separator 61 and an oxygen-side gas-liquid separator 71 on the hydrogen side and oxygen side, respectively. The gas-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71 are respectively provided with liquid reflux ports. The hydrogen-side gas-liquid separator 61 is connected to the cathode of the electrolytic cell unit 1, and the oxygen-side gas-liquid separator 71 is connected to the anode of the electrolytic cell unit 1. The hydrogen-side gas-liquid separator 61 is used to separate hydrogen and water vapor generated at the cathode of the electrolytic cell unit 1, and the oxygen-side gas-liquid separator 71 is used to separate oxygen and water vapor generated at the anode of the electrolytic cell unit 1.

[0050] This embodiment, by independently configuring the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71, can efficiently separate the gas-liquid mixture at the cathode and anode outlets, significantly reducing the liquid entrainment content in hydrogen and oxygen. This helps to reduce the processing load on subsequent precision dryers, purification devices, and other units, improve their working efficiency and operational stability, thereby extending the service life of the entire system.

[0051] In one embodiment, a pressure control unit is disposed between the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71. The pipe 83 of the pressure control unit is directly connected to the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71. The pressure sensor 81 on the pipe 83 feeds back the pressure signals from both sides to the central controller in real time. The central controller adjusts the pressure difference between the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71 through the pressure balancing valve 82.

[0052] The technical solution provided in this embodiment achieves real-time monitoring and active adjustment of the gas pressure on both the cathode and anode sides of the electrolytic cell by setting a pressure sensor 81 between the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71. This effectively avoids irreversible mechanical damage to the anion exchange membrane caused by uneven pressure on both sides, and helps to improve the safety and stability of the system.

[0053] Please see Figure 2 Secondly, one embodiment of this application also provides a method for producing hydrogen by anion exchange membrane water electrolysis in plateau areas, the method comprising: S1: The central control and coordination unit provides DC power to the electrolytic cell unit 1. The central control and regulation unit integrates a central controller, which communicates with each unit to automatically operate and control the system. S3: The alkaline solution with a concentration and temperature that meet the preset standards is obtained through the liquid supply unit, and the alkaline solution is supplied to the cathode of the electrolytic cell unit 1 through the single cathode liquid supply method, and the condensate generated by the gas-liquid separation and purification unit is recovered. S5: Electrolyze the alkaline solution from the supply unit through the electrolytic cell unit 1 to generate hydrogen at the cathode and oxygen at the anode, and supply the generated gas to the gas-liquid separation and purification unit. S7: The hydrogen generated at the cathode is separated and purified through the hydrogen side in the gas-liquid separation and purification unit, and the oxygen generated at the anode is separated and purified through the oxygen side in the gas-liquid separation and purification unit. The condensate generated during the separation and purification process is returned to the liquid supply unit. S9: The pressure control unit balances the pressure on the hydrogen side and the oxygen side in the gas-liquid separation and purification unit.

[0054] Further functional descriptions of the above steps are the same as those in the corresponding system embodiments described above, and will not be repeated here.

[0055] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0056] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0057] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0058] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A hydrogen and oxygen production system for water electrolysis using anion exchange membranes, designed for high-altitude environments, characterized in that... The system includes a liquid supply unit, an electrolytic cell unit, a gas-liquid separation and purification unit, a pressure control unit, and a central control and coordination unit. The liquid supply unit is connected to the electrolytic cell unit, and the electrolytic cell unit is connected to the gas-liquid separation and purification unit. The liquid reflux port of the gas-liquid separation and purification unit is connected to the liquid supply unit. The pressure control unit is connected to both the hydrogen and oxygen sides of the gas-liquid separation and purification unit. The central control and coordination unit is connected to the electrolytic cell unit. The liquid supply unit is used to obtain an alkaline solution with a concentration and temperature that meet preset standards, and supplies the alkaline solution to the cathode of the electrolytic cell unit through a single cathode liquid supply method, and recovers the condensate generated by the gas-liquid separation and purification unit. The electrolytic cell unit is used to electrolyze the alkaline solution from the liquid supply unit to generate hydrogen at the cathode and oxygen at the anode, and to supply the generated gas to the gas-liquid separation and purification unit. The hydrogen side of the gas-liquid separation and purification unit is used to separate and purify the hydrogen generated by the cathode, and the oxygen side of the gas-liquid separation and purification unit is used to separate and purify the oxygen generated by the anode. The condensate generated during the separation and purification process is returned to the liquid supply unit. The pressure control unit is used to control the pressure on the hydrogen side and the oxygen side in the gas-liquid separation and purification unit, so that the pressure difference between the hydrogen side and the oxygen side is maintained within a set range; The central control and coordination unit is used to provide DC power to the electrolytic cell unit and integrates a central controller; the central controller is communicatively connected to each unit to automatically operate and control the system.

2. The system according to claim 1, characterized in that, The pressure control unit includes a pressure sensor, a pressure balancing valve, and a pipeline. The pipeline connects the hydrogen side and the oxygen side of the gas-liquid separation and purification unit. The pressure sensor and the pressure balancing valve are mounted on the pipeline. The pressure sensor is used to feed back pressure signals from the hydrogen side and the oxygen side to the central control and coordination unit. The central controller in the central control and coordination unit adjusts the opening of the pressure balancing valve according to the pressure signals to control the pressure difference between the hydrogen side and the oxygen side within a preset pressure difference range.

3. The system according to claim 1, characterized in that, The gas-liquid separation and purification unit is equipped with a hydrogen-side back pressure valve and an oxygen-side back pressure valve at the hydrogen and oxygen sides, respectively: The central control and coordination unit is specifically used to coordinate and control the hydrogen-side back pressure valve, the oxygen-side back pressure valve, and the pressure control unit to adjust the pressure difference between the hydrogen side and the oxygen side.

4. The system according to claim 1, characterized in that, The liquid supply unit includes an alkali buffer tank, and a first branch, a second branch, and a third branch connected to the alkali buffer tank, wherein: The first branch is used to supply deionized water to the alkaline buffer tank; The second branch is used to supply alkaline solution to the alkaline buffer tank; The alkaline buffer tank is used to mix the deionized water and the alkaline solution, and to adjust the concentration of the mixed alkaline solution. The third branch is used to adjust the temperature of the alkaline solution output from the alkaline solution buffer tank to obtain an alkaline solution with a concentration and temperature that meet the preset standards, and to supply the alkaline solution with a concentration and temperature that meet the preset standards to the cathode of the electrolytic cell unit through a single cathode supply method.

5. The system according to claim 4, characterized in that, The first branch includes a water replenishment pump, a purification device, and a deionization device connected in sequence; the second branch includes an alkali addition device.

6. The system according to claim 4, characterized in that, The third branch includes a circulating pump, a heat exchanger, and a flow control valve, wherein: The heat exchanger is used to control the temperature of the alkaline solution output by the circulating pump.

7. The system according to claim 4, characterized in that, The alkaline buffer tank is also equipped with a concentration sensor, wherein: The concentration sensor is used to detect the concentration of alkali solution in the alkali solution buffer tank; the central control and coordination unit controls the central controller to perform alkali solution dilution or alkali solution replenishment operation based on the detection result; The alkaline buffer tank is also used to recover the condensate separated by the gas-liquid separation and purification unit.

8. The system according to claim 1, characterized in that, The gas-liquid separation and purification unit is equipped with a hydrogen-side gas-liquid separator and an oxygen-side gas-liquid separator on the hydrogen and oxygen sides, respectively. The hydrogen-side gas-liquid separator is connected to the cathode of the electrolytic cell unit, and the oxygen-side gas-liquid separator is connected to the anode of the electrolytic cell unit. The hydrogen-side gas-liquid separator is used to separate hydrogen and water vapor produced by the cathode of the electrolytic cell unit. The oxygen-side gas-liquid separator is used to separate the oxygen and water vapor produced by the anode of the electrolytic cell unit.

9. The system according to claim 8, characterized in that, The pressure control unit is located between the hydrogen-side gas-liquid separator and the oxygen-side gas-liquid separator.

10. A method for producing hydrogen and oxygen from anion exchange membrane water electrolysis, applicable to any of the plateau-oriented anion exchange membrane water electrolysis systems described in claims 1 to 9, characterized in that, The method includes: The alkaline solution with a concentration and temperature that meet the preset standards is obtained through the liquid supply unit, and the alkaline solution is supplied to the cathode of the electrolytic cell unit through a single cathode liquid supply method, and the condensate generated by the gas-liquid separation and purification unit is recovered. The alkaline solution from the supply unit is electrolyzed through the electrolytic cell unit to generate hydrogen at the cathode and oxygen at the anode, and the generated gas is provided to the gas-liquid separation and purification unit. The hydrogen generated at the cathode is separated and purified through the hydrogen side of the gas-liquid separation and purification unit, and the oxygen generated at the anode is separated and purified through the oxygen side of the gas-liquid separation and purification unit. The condensate generated during the separation and purification process is returned to the liquid supply unit. The pressure control unit controls the pressure on the hydrogen side and the oxygen side in the gas-liquid separation and purification unit, so that the pressure difference between the hydrogen side and the oxygen side is maintained within a set range. The central control and coordination unit provides DC power to the electrolytic cell unit. The central control and coordination unit integrates a central controller, which communicates with each unit to automatically operate and control the system.

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