A proton exchange membrane water electrolysis hydrogen production process system capable of switching between balanced and differential pressure operation modes and a control method thereof

Abstract

The present application relates to the technical field of hydrogen production by hydrolysis, and particularly relates to a proton exchange membrane water electrolysis hydrogen production process system capable of switching operation under balanced or differential pressure conditions and a control method. The hydrogen production system is an innovative design of different process route equipment and control required for operation under balanced or differential pressure conditions, and is realized in a proton exchange membrane water electrolysis hydrogen production process system. The hydrogen production system has the advantages that the high current density, high efficiency, fast dynamic response and adaptability to renewable energy fluctuation of the proton exchange membrane water electrolysis tank are fully utilized, the pressure difference resistance characteristics of both sides of the proton exchange membrane are utilized, the requirements of different subsequent use scenarios after hydrogen production are met, the process system can operate under balanced and differential pressure conditions, the application scenarios are wide, the operation is flexible, the dynamic response capability is efficient, the system maintenance is simple, the safety is good, and the environmental friendliness is good.

Description

Technical Field

[0001] The present invention relates to the technical field of water electrolysis hydrogen production, and in particular to a proton exchange membrane water electrolysis hydrogen production process system and a control method capable of switchably operating under equilibrium or differential pressure conditions. Background Art

[0002] In recent years, facing the current state of environmental pollution, countries around the world have increased their efforts to develop new energy sources. Hydrogen is an environmentally friendly, renewable, storable, diverse, and abundant clean energy source that can meet the requirements of environmental, resource, and social sustainability. Hydrogen production through water electrolysis can be used to absorb waste electricity generated by renewable energy sources such as photovoltaic and wind power, converting electricity into hydrogen. This method offers high hydrogen purity, a pollution-free production process, and flexible hydrogen production scale. However, renewable energy sources generally suffer from poor stability and low utilization rates. Renewable energy consumption is a key technology hindering its development.

[0003] Hydrogen energy storage is one of the effective solutions to the problem of renewable energy absorption. Hydrogen production from renewable energy not only increases the cleanliness of the power grid, but also can use hydrogen to achieve peak-shaving energy storage in the power grid and increase the absorption ratio.

[0004] Proton exchange membrane (PEM) water electrolysis hydrogen production technology has the characteristics of higher operating current density, high efficiency, and fast dynamic response speed, and is considered to be a water electrolysis hydrogen production technology with great development prospects. The large-scale consumption of renewable energy has expanded the application market of proton exchange membrane (PEM) water electrolysis hydrogen production technology. Currently, in the domestic market, most of the differential pressure working process systems are based on atmospheric pressure venting on the oxygen side, and balanced working conditions are rare. Therefore, the present invention is a proton exchange membrane (PEM) water electrolysis hydrogen production process system and control method that can switch between balanced and differential pressure working conditions. It has a wide range of application scenarios, flexible operation, efficient dynamic response capability, simple system maintenance, good safety, and good environmental friendliness. Summary of the Invention

[0005] The purpose of the present invention is to provide a proton exchange membrane (PEM) water electrolysis hydrogen production process system and control method that can switch between balanced and differential pressure operating conditions. The system utilizes the pressure difference resistance of the proton exchange membrane itself and can adapt to the different requirements of subsequent hydrogen production scenarios. The system can operate under balanced and differential pressure conditions, has a wide range of applicable scenarios, flexible operation, efficient dynamic response capability, simple system maintenance, good safety, and good environmental friendliness.

[0006] The core point of the invention is the switching control of different working conditions:

[0007] The pressure control of the proton exchange membrane (PEM) water electrolysis hydrogen production process system is switched between balanced and differential pressure modes, and is controlled by the pressure differential detection control module, the oxygen side regulation module 16 (dual valve) and the hydrogen side regulation module 17 (dual valve).

[0008] The conductivity of the proton exchange membrane (PEM) water electrolysis hydrogen production process system is regulated by setting a conductivity detection control module in the pure water circulation tank 4, a three-way adjustment module 18 (or a regulating valve module is set on each of the two branches), a temperature difference control module before the pure water inlet pipe of the electrolytic cell 8, and a flow detection control module.

[0009] The oxygen side water replenishment system of the proton exchange membrane (PEM) water electrolysis hydrogen production process system is switched to operate under balanced or differential pressure conditions, through the raw water purification module 1, the remote switch module 14, the remote switch module 15, the water replenishment tank 2 and the water replenishment pump 3.

[0010] The hydrogen side condensate recycling system of the proton exchange membrane (PEM) water electrolysis hydrogen production process system is switched under balanced or differential pressure conditions, through the condensate buffer tank 12, the condensate delivery pump 13, the remote switch module 19, the remote switch module 20, the water replenishment tank 2, and the pure water circulation tank 4.

[0011] This hydrogen production system innovatively designs the equipment and controls for different process routes required for operation under balanced or differential pressure conditions, and implements it in a proton exchange membrane water electrolysis hydrogen production process system. Its advantages are that it fully utilizes the high current density, high efficiency, rapid dynamic response and adaptability to the volatility of renewable energy sources such as wind and solar power of the proton exchange membrane water electrolyzer. At the same time, it utilizes the pressure difference resistance characteristics of the two sides of the proton exchange membrane itself, and can adapt to the different requirements of subsequent hydrogen production scenarios. This process system can operate under both balanced and differential pressure conditions, with a wide range of applicable scenarios, flexible operation, efficient dynamic response capability, simple system maintenance, good safety, and good environmental friendliness.

[0012] A proton exchange membrane (PEM) water electrolysis hydrogen production process system and control method capable of switching between balanced and differential pressure operating conditions has the following innovations:

[0013] 1. Zero discharge of hydrogen side return water under balanced or differential pressure conditions, with different return water paths.

[0014] 2. Adjust the conductivity of process water, that is, divert part of the water proportionally to the pure water deionization column of the electrolytic cell for deionization.

[0015] 3. The pressure control of the proton exchange membrane (PEM) water electrolysis hydrogen production process system is switched between balanced and differential pressure modes and is controlled by the pressure differential detection control module. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a system schematic diagram of a proton exchange membrane water electrolysis hydrogen production process system that can switch between balanced and differential pressure operating conditions, provided by an embodiment of the present invention.

[0018] Reference numerals:

[0019] 1Raw water purification module,

[0020] 2 water tanks,

[0021] 3 water supply pumps,

[0022] 4 pure water circulation tank,

[0023] 5 pure water circulation pump,

[0024] 6 ion columns,

[0025] 7 pure water cooler,

[0026] 8 electrolytic cells,

[0027] 9Gas-liquid separator,

[0028] 10 Hydrogen cooler,

[0029] 11 Hydrogen purification module (including deaerator),

[0030] 12 condensate buffer tank,

[0031] 13 condensate delivery pump,

[0032] 14-15 remote switch module,

[0033] 16-17 adjustment module,

[0034] 18 three-way adjustment module,

[0035] 19-20 Remote switch module. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] like Figure 1 As shown, an embodiment of the present invention provides a proton exchange membrane water electrolysis hydrogen production process system that can switch between balanced and differential pressure working conditions, including: a raw water purification module, an oxygen side water replenishment system, an oxygen side pure water heat exchange and circulation system, an oxygen side water conductivity regulation system, a proton exchange membrane water electrolyzer module, an oxygen side gas-liquid separation equipment system, a hydrogen side gas-liquid separation system, a hydrogen purification module, a hydrogen side condensate reuse system, a conductivity detection control module, a temperature detection control module, a temperature difference control module, a flow detection control module, a pressure difference detection control module, an oxygen side regulation module, a hydrogen side regulation module, a three-way regulation module, and a remote switch module. The balanced working condition is that the safety pressure difference between the hydrogen and oxygen sides is greater than 5kPa and the gauge pressure of the hydrogen side is 0.15MPa~3.0MPa. The differential pressure working condition is that the oxygen side pressure is normal pressure and the hydrogen side gauge pressure is 0.15MPa~3.0MPa.

[0038] In this embodiment, the hydrogen production system innovatively designs the equipment and controls for different process routes required for operation under balanced or differential pressure conditions, and implements them in a proton exchange membrane water electrolysis hydrogen production process system. Its advantages are that it fully utilizes the high current density, high efficiency, rapid dynamic response and adaptability to the volatility of renewable energy sources such as wind and solar power of the proton exchange membrane water electrolyzer, while utilizing the pressure difference resistance characteristics on both sides of the proton exchange membrane itself, which can adapt to the different requirements of subsequent hydrogen production scenarios. This process system can operate under both balanced and differential pressure conditions, with a wide range of applicable scenarios, flexible operation, efficient dynamic response capability, simple system maintenance, good safety, and good environmental friendliness.

[0039] In one embodiment of the present invention, for the oxygen side water replenishment system, a conductivity detection module is set at the outlet of the raw water purification module 1, a remote switch module 14 is set between the outlet of the raw water purification module 1 and the inlet of the water replenishment tank 2, and a remote switch module 15 is set between the outlet of the raw water purification module 1 and the inlet of the pure water circulation tank 4. The opening and closing states of the remote switch module 14 and the remote switch module 15 are opposite to each other.

[0040] In one embodiment of the present invention, for the oxygen side pure water heat exchange and circulation system, a temperature detection control module is set in the pure water circulation tank 4; a three-way adjustment module 18 is set at the node of the pure water circulation pump 5 outlet, the ion column 6 inlet and the pure water cooler 7 inlet pipeline, and is interlocked with the temperature difference control module and the flow detection control module before the pure water inlet pipeline into the electrolytic tank 8. At least one temperature detection control module, temperature difference control module and flow detection control module are set between the pure water cooler 7 outlet and the oxygen side water inlet of the electrolytic tank 8.

[0041] In one embodiment of the present invention, for the oxygen side gas-liquid separation equipment system, at least one temperature detection control module, a temperature difference control module, and a pressure difference detection control module are set between the oxygen side outlet of the electrolytic cell 8 and the inlet of the pure water circulation tank 4, and a regulating module 16 is set at the oxygen side outlet of the pure water circulation tank 4.

[0042] In one embodiment of the present invention, for the oxygen side water conductivity regulation system, a conductivity detection control module is provided in the pure water circulation tank 4 , and a three-way regulation module 18 is provided between the outlet of the pure water circulation pump 5 and the inlet of the ion column 6 .

[0043] In one embodiment of the present invention, for the hydrogen side gas-liquid separation system, at least one pressure difference detection control module is provided between the hydrogen side outlet of the electrolyzer 8 and the inlet of the gas-liquid separator 9 , and a regulating module 17 is provided at the outlet of the hydrogen purification module 11 .

[0044] In one embodiment of the present invention, for the hydrogen side condensate reuse system, the liquid phase outlet of the gas-liquid separator 9, the liquid phase outlet of the hydrogen cooler 10 and the liquid phase outlet of the hydrogen purification module 11 are all connected to the inlet of the condensate buffer tank 12, and the outlet of the condensate delivery pump 13 is respectively connected to the inlet of the water replenishment tank 2 and the inlet of the pure water circulation tank 4, and the opening and closing states of the remote switch module 19 and the remote switch module 20 are opposite to each other.

[0045] In one embodiment of the present invention, both the oxygen-side regulating module 16 and the hydrogen-side regulating module 17 are controlled by a pressure difference detection control module, and both are double valves.

[0046] In addition, an embodiment of the present invention further provides a control method for a proton exchange membrane water electrolysis hydrogen production process system that can switch between operating in a balanced or differential pressure mode. Based on the system mentioned in the above embodiment, under the balanced operating condition, the method includes:

[0047] The raw water is connected to the raw water purification module 1 from the outside and processed into pure water with the conductivity required by the system. When the system is started for the first time under balanced working conditions, the pure water is directly added to the pure water circulation tank 4 through the remote switch module 15. After meeting the requirements, the remote switch module 15 is turned off. After that, the pure water required by the system enters the water replenishment tank 2 through the remote switch module 14. At the same time, the hydrogen side water returned by the condensate delivery pump 13 through the remote switch module 19 is collected. These two streams of water are replenished into the pure water circulation tank 4 through the water replenishment pump 3.

[0048] The pure water in the pure water circulation tank 4 passes through the pure water circulation pump 5 and the temperature difference control module and the flow detection control module before entering the pure water inlet pipe of the electrolyzer 8 to control the pure water to enter the pure water cooler 7 for cooling and heat exchange, and at the same time adjusts and controls the cooling water flow of the pure water cooler 7 to ensure that the pure water temperature entering the proton exchange membrane water electrolyzer 8 module is controlled within the design range. The oxygen-enriched water at the oxygen side outlet of the electrolyzer 8 enters the pure water circulation tank 4 for circulation;

[0049] Oxygen-enriched water from the oxygen side outlet of the electrolytic cell 8 enters the pure water circulation tank 4 for gas-liquid two-phase separation. Under the control of the pressure difference detection control module, the gaseous oxygen is regulated in volume and pressure by the oxygen side regulating module 16, and then the oxygen is exhausted outside the system or used for subsequent processes.

[0050] The pure water in the pure water circulation tank 4 is controlled by the pure water circulation pump 5 and the conductivity detection control module in the pure water circulation tank 4 to adjust the three-way regulating module 18 to control the pure water to be diverted into the ion column 6 for deionization, and the pure water at the outlet of the ion column 6 enters the pure water circulation tank 4;

[0051] The wet hydrogen from the hydrogen side outlet of the electrolyzer 8 enters the gas-liquid separator 9 for primary gas-liquid two-phase separation. The separated hydrogen enters the hydrogen cooler 10 for secondary gas-liquid two-phase separation and cooling. The hydrogen at the outlet of the hydrogen cooler 10 is connected to the hydrogen purification module 11 for purification. The outlet of the hydrogen purification module 11 is controlled by the pressure difference detection control module. After the gas volume and pressure of the finished hydrogen are adjusted by the hydrogen side regulation module 17, the finished hydrogen is stored in the hydrogen storage equipment or sent to the subsequent process after ensuring that the oxygen content and dew point in the hydrogen are qualified.

[0052] The hydrogen side water separated twice by the gas-liquid separator 9 and the hydrogen cooler 10 and the water discharged from the hydrogen purification module 11 enter the condensed water buffer tank 12 for cache. The pure hydrogen side water at the outlet of the condensed water buffer tank 12 is returned to the water replenishment tank 2 for reuse by the condensed water delivery pump 13 through the remote switch module 19.

[0053] In one embodiment of the present invention, under differential pressure working conditions, the process includes:

[0054] Raw water is connected from outside to the raw water purification module 1 and processed into pure water with the conductivity required by the system. Under differential pressure conditions, pure water is directly added to the pure water circulation tank 4 through the remote switch module 15. The pure water required for subsequent system replenishment is replenished from this line;

[0055] The pure water in the pure water circulation tank 4 passes through the pure water circulation pump 5 and the temperature difference control module and the flow detection control module before entering the pure water inlet pipe of the electrolyzer 8 to control the pure water to enter the pure water cooler 7 for cooling and heat exchange, and at the same time adjusts and controls the cooling water flow of the pure water cooler 7 to ensure that the pure water temperature entering the proton exchange membrane water electrolyzer 8 module is controlled within the design range. The oxygen-enriched water at the oxygen side outlet of the electrolyzer 8 enters the pure water circulation tank 4 for circulation;

[0056] Oxygen-enriched water from the oxygen side outlet of the electrolytic cell 8 enters the pure water circulation tank 4 for gas-liquid two-phase separation. Under the control of the pressure difference detection control module, the oxygen side regulating module 16 is changed to fully open, and the oxygen is exhausted outside the system or used for subsequent processes under normal pressure;

[0057] The pure water in the pure water circulation tank 4 is controlled by the pure water circulation pump 5 and the conductivity detection control module in the pure water circulation tank 4 to adjust the three-way regulating module 18 to control the pure water to be diverted into the ion column 6 for deionization, and the pure water at the outlet of the ion column 6 enters the pure water circulation tank 4;

[0058] The wet hydrogen from the hydrogen side outlet of the electrolyzer 8 enters the gas-liquid separator 9 for primary gas-liquid two-phase separation. The separated hydrogen enters the hydrogen cooler 10 for secondary gas-liquid two-phase separation and cooling. The hydrogen at the outlet of the hydrogen cooler 10 is connected to the hydrogen purification module 11 for purification. The outlet of the hydrogen purification module 11 is controlled by the pressure difference detection control module. After the gas volume and pressure of the finished hydrogen are adjusted by the hydrogen side regulation module 17, the finished hydrogen is stored in the hydrogen storage equipment or sent to the subsequent process after ensuring that the oxygen content and dew point in the hydrogen are qualified.

[0059] The hydrogen side water separated twice by the gas-liquid separator 9 and the hydrogen cooler 10 and the water discharged from the hydrogen purification module 11 enter the condensed water buffer tank 12 for cache. The pure hydrogen side water at the outlet of the condensed water buffer tank 12 is returned to the pure water circulation tank 4 for reuse by the condensed water delivery pump 13 through the remote switch module 20.

[0060] It should be noted that, in this article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical factors in the process, method, article or device comprising the elements.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A proton exchange membrane water electrolysis hydrogen production process system that can switch between balanced and differential pressure operating conditions, characterized in that: It includes a raw water purification module, an oxygen side water replenishment system, an oxygen side pure water heat exchange and circulation system, an oxygen side water conductivity regulation system, a proton exchange membrane water electrolyzer module, an oxygen side gas-liquid separation equipment system, a hydrogen side gas-liquid separation system, a hydrogen purification module, a hydrogen side condensate recycling system, a conductivity detection control module, a temperature detection control module, a temperature difference control module, a flow detection control module, a pressure difference detection control module, an oxygen side regulation module, a hydrogen side regulation module, a three-way regulation module and a remote switch module. The balanced working condition is that the safety pressure difference between the hydrogen and oxygen sides is greater than 5kPa and the gauge pressure of the hydrogen side is 0.15MPa to 3.0MPa. The differential pressure working condition is that the oxygen side pressure is normal pressure and the hydrogen side gauge pressure is 0.15MPa to 3.0MPa. For the oxygen-side water replenishment system, a conductivity detection module is provided at the outlet of the raw water purification module, a first remote switch module is provided between the outlet of the raw water purification module and the inlet of the water replenishment tank, and a second remote switch module is provided between the outlet of the raw water purification module and the inlet of the pure water circulation tank. The opening and closing states of the first remote switch module and the second remote switch module are opposite to each other; For the oxygen-side pure water heat exchange and circulation system, the pure water circulation tank is provided with a temperature detection control module; a three-way adjustment module is provided at the pipeline node of the pure water circulation pump outlet, the ion column inlet and the pure water cooler inlet. The three-way adjustment module is interlocked with the temperature difference control module and the flow detection control module provided in front of the pure water inlet pipe of the electrolyzer. At least one temperature detection control module, a temperature difference control module and a flow detection control module are provided between the pure water cooler outlet and the oxygen-side water inlet of the electrolyzer; For the oxygen side gas-liquid separation equipment system, at least one temperature detection control module, a temperature difference control module and a pressure difference detection control module are respectively provided between the oxygen side outlet of the electrolytic cell and the inlet of the pure water circulation tank, and an oxygen side regulation module is provided at the oxygen outlet of the pure water circulation tank; For the oxygen side water conductivity regulation system, a conductivity detection control module is set in the pure water circulation tank, and a three-way regulation module is set between the pure water circulation pump outlet and the ion column inlet; For the hydrogen side gas-liquid separation system, at least one pressure difference detection control module is provided between the hydrogen side outlet of the electrolyzer and the gas-liquid separator inlet, and a hydrogen side regulation module is provided at the outlet of the hydrogen purification module; For the hydrogen-side condensate reuse system, the liquid phase outlet of the gas-liquid separator, the liquid phase outlet of the hydrogen cooler, and the liquid phase outlet of the hydrogen purification module are all connected to the inlet of the condensate buffer tank, and the outlet of the condensate delivery pump is respectively connected to the inlet of the water supply tank and the inlet of the pure water circulation tank. The on and off states of the third remote switch module and the fourth remote switch module are opposite to each other, so that the hydrogen-side pure water at the outlet of the condensate buffer tank is returned to the water supply tank for reuse by the condensate delivery pump through the third remote switch module or returned to the pure water circulation tank for reuse through the fourth remote switch module; The oxygen side regulating module and the hydrogen side regulating module are both controlled by the pressure difference detection control module, and both are double valves.

2. A control method for a proton exchange membrane water electrolysis hydrogen production process system capable of switching between balanced and differential pressure operating modes, characterized in that: The system according to claim 1, under balanced working conditions, comprises: Raw water is connected from outside to the raw water purification module for processing into pure water with the conductivity required by the system. During the first startup under balanced conditions, the pure water is directly added to the pure water circulation tank through the second remote switch module. After the requirements are met, the second remote switch module is closed. After that, the pure water required by the system enters the water replenishment tank through the first remote switch module. At the same time, the hydrogen side water returned by the condensate transfer pump through the remote switch module is collected. These two water streams are replenished into the pure water circulation tank through the water replenishment pump. The pure water in the pure water circulation tank passes through the pure water circulation pump and controls the temperature difference control module and the flow detection control module before entering the pure water inlet pipe of the electrolyzer to control the pure water to enter the pure water cooler for cooling and heat exchange. At the same time, the cooling water flow of the pure water cooler is adjusted to ensure that the pure water temperature entering the proton exchange membrane water electrolyzer module is within the design range. The oxygen-enriched water at the oxygen side outlet of the electrolyzer enters the pure water circulation tank for circulation; The oxygen-rich water at the oxygen side outlet of the electrolyzer enters the pure water circulation tank for gas-liquid two-phase separation. Under the control of the pressure difference detection control module, the gaseous oxygen is regulated in volume and pressure by the oxygen side regulation module before being discharged outside the system. The pure water in the pure water circulation tank is pumped through the conductivity detection control module in the pure water circulation tank to adjust the three-way regulating module to control the pure water diversion into the ion column for deionization. The pure water at the outlet of the ion column enters the pure water circulation tank; The wet hydrogen at the hydrogen side outlet of the electrolyzer enters the gas-liquid separator for primary gas-liquid two-phase separation. The separated hydrogen enters the hydrogen cooler for secondary gas-liquid two-phase separation and cooling. The hydrogen at the outlet of the hydrogen cooler is connected to the hydrogen purification module for purification. The outlet of the hydrogen purification module is controlled by the pressure difference detection control module. The finished hydrogen is adjusted in gas volume and pressure by the hydrogen side regulation module. After ensuring that the oxygen content and dew point in the hydrogen are qualified, the finished hydrogen is stored in the hydrogen storage equipment; The hydrogen side water separated twice by the gas-liquid separator and hydrogen cooler and the water discharged from the hydrogen purification module enter the condensate buffer tank for cache. The pure hydrogen side water at the outlet of the condensate buffer tank is returned to the water replenishment tank for reuse by the condensate transfer pump through the third remote switch module.

3. The method according to claim 2, characterized in that In differential pressure mode, it includes: Raw water is connected from outside to the raw water purification module and processed into pure water with the conductivity required by the system. Under differential pressure conditions, pure water is directly added to the pure water circulation tank through the second remote switch module. The pure water replenishment required by the subsequent system is replenished from this line; The pure water in the pure water circulation tank passes through the pure water circulation pump and controls the temperature difference control module and the flow detection control module before entering the pure water inlet pipe of the electrolyzer to control the pure water to enter the pure water cooler for cooling and heat exchange. At the same time, the cooling water flow of the pure water cooler is adjusted to ensure that the pure water temperature entering the proton exchange membrane water electrolyzer module is within the design range. The oxygen-enriched water at the oxygen side outlet of the electrolyzer enters the pure water circulation tank for circulation; The oxygen-rich water at the oxygen side outlet of the electrolyzer enters the pure water circulation tank for gas-liquid two-phase separation. Under the control of the pressure difference detection control module, after the oxygen side regulation module is fully opened, the oxygen is discharged outside the system at normal pressure. The pure water in the pure water circulation tank is pumped through the conductivity detection control module in the pure water circulation tank to adjust the three-way regulating module to control the pure water diversion into the ion column for deionization. The pure water at the outlet of the ion column enters the pure water circulation tank; The wet hydrogen at the hydrogen side outlet of the electrolyzer enters the gas-liquid separator for primary gas-liquid two-phase separation. The separated hydrogen enters the hydrogen cooler for secondary gas-liquid two-phase separation and cooling. The hydrogen at the outlet of the hydrogen cooler is connected to the hydrogen purification module for purification. The outlet of the hydrogen purification module is controlled by the pressure difference detection control module. The finished hydrogen is adjusted in gas volume and pressure by the hydrogen side regulation module. After ensuring that the oxygen content and dew point in the hydrogen are qualified, the finished hydrogen is stored in the hydrogen storage equipment; The hydrogen side water separated twice by the gas-liquid separator and hydrogen cooler and the water discharged from the hydrogen purification module enter the condensate buffer tank for cache. The pure hydrogen side water at the outlet of the condensate buffer tank is returned to the pure water circulation tank for reuse by the condensate transfer pump through the fourth remote switch module.

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