A heat exchange system for proton exchange membrane water electrolysis hydrogen production

Abstract

This invention discloses a heat exchange system for hydrogen production via proton exchange membrane water electrolysis, comprising a cold source supply device; a hydrogen separation system; and an oxygen separation system. The cold source supply device simultaneously provides a cold source medium to both the hydrogen and oxygen separation systems via pipelines, and the cold source medium returns to the cold source supply device after passing through the hydrogen and oxygen separation systems respectively. A hydrogen delivery pipe is connected at one end to the hydrogen side of the electrolyzer and at the other end to the hydrogen separation system. An oxygen delivery pipe is connected at one end to the oxygen side of the electrolyzer and at the other end to the oxygen separation system. The cold source supply device of this application can simultaneously provide a cold source for both the hydrogen and oxygen separation systems. The flow control system allows the two separation processes to share a single cold source system, achieving thermodynamic balance, simplifying the overall system layout, reducing equipment investment costs, and lowering energy consumption during system operation.

Description

Technical Field

[0001] This invention relates to the field of proton exchange membrane water electrolysis technology, and in particular to a heat exchange system for proton exchange membrane water electrolysis to produce hydrogen. Background Technology

[0002] Proton exchange membrane (PEM) water electrolysis for hydrogen production demonstrates significant advantages in industrial applications due to its rapid response and dynamic adaptability. PEM equipment can achieve load changes within seconds (0~105% power), with a minimum sustaining load of only 3% of the system's rated power, allowing for high compatibility with actual production needs. Simultaneously, PEM equipment possesses excellent direct coupling capabilities with renewable energy sources, enabling seamless grid connection with wind, solar, and tidal power, efficiently converting electrical energy into hydrogen energy with an efficiency loss of less than 5%. Currently, hydrogen production ranges from 50 to 200 Nm³. 3 PEM equipment in the / h range is in high demand in the end market: on the one hand, this gas production range completely overlaps with alkaline (ALK) electrolysis, while the cost is close to the ALK level, so customers prefer PEM; on the other hand, under the guidance of policies, the zero carbon emission characteristics of PEM have significant advantages.

[0003] In existing PEM water electrolysis hydrogen production systems, the hydrogen gas-liquid separation system (GLS) and the gas purification system (HPS) involve different thermal management requirements. In the HPS system, the temperature of the purified qualified hydrogen is approximately 60°C, which needs to be cooled to approximately 40°C by a heat exchanger. The heat exchanger's cooling source is an external chilled water supply (inlet water temperature 7~12°C). Figure 6 In the GLS system, the gas-water mixture (GLSH on the hydrogen side and GLSO on the oxygen side) produced by the electrolyzer is condensed in its respective heat exchangers, reducing the gas-water temperature from approximately 60°C to approximately 40°C. This causes hydrogen and oxygen to be released from the water, and the water is reused through a circulation loop. The heat exchangers are cooled by an external cooling tower (inlet water temperature 18~20°C). Figure 7 .

[0004] However, the aforementioned thermal management architecture has the following shortcomings in actual operation: Existing systems typically employ a thermal management architecture where the chiller and cooling tower operate independently and in parallel. In actual operating conditions, the heat load of the electrolyzer and the cooling demand of the gas purification end are often not synchronized (for example, only cooling is required during startup, not dehumidification). The traditional architecture lacks a thermal coupling mechanism, often resulting in the chiller being in a state of "over-powered operation" or the cooling tower still requiring high-frequency fan operation in low-temperature environments, producing a severe "heat cancellation" phenomenon, leading to high energy consumption under the existing thermal management architecture. To address this, this application proposes a heat exchange system for proton exchange membrane water electrolysis to produce hydrogen, in order to solve these problems. Summary of the Invention

[0005] Based on this, in order to solve the problems existing in the prior art, this application provides a heat exchange system for proton membrane water electrolysis to produce hydrogen, including a cold source supply device, which is used to generate a cold source medium. Hydrogen separation system, used to separate hydrogen from hydrogen gas-liquid mixture; An oxygen separation system is used to separate oxygen from an oxygen-liquid mixture. The cold source supply equipment provides cold source medium to both the hydrogen separation system and the oxygen separation system through pipelines, and the cold source medium flows back to the cold source supply equipment after passing through the hydrogen separation system and the oxygen separation system respectively. The flow control system is used to regulate the flow rate of the cold source medium input to the hydrogen separation system and the oxygen separation system based on temperature feedback. The hydrogen delivery pipe has one end connected to the hydrogen side of the electrolyzer and the other end connected to the hydrogen separation system. The oxygen delivery pipe has one end connected to the oxygen side of the electrolytic cell and the other end connected to the oxygen separation system.

[0006] Furthermore, it also includes a first branch pipe and a second branch pipe, which are connected in parallel and then in series with the pipeline. The hydrogen separation system is connected in series with the first branch pipe, and the oxygen separation system is connected in series with the second branch pipe.

[0007] Furthermore, the hydrogen separation system includes a first heat exchanger, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe is connected to the gas-liquid channel of the first heat exchanger, and the first branch pipe is connected to the cold source channel of the first heat exchanger.

[0008] Furthermore, the flow control system includes a first regulating valve and a first temperature sensor. The first regulating valve is electrically connected to the first temperature sensor. The first regulating valve is installed on a first branch pipe before being connected to the first heat exchanger, and the first temperature sensor is installed on a first branch pipe after being connected to the first heat exchanger.

[0009] Furthermore, the oxygen separation system includes a second heat exchanger, which has a gas-liquid passage and a cold source passage. The oxygen delivery pipe is connected to the gas-liquid passage of the second heat exchanger, and the second branch pipe is connected to the cold source passage of the second heat exchanger.

[0010] Furthermore, the flow control system includes a second regulating valve and a second temperature sensor. The second regulating valve is electrically connected to the second temperature sensor. The second regulating valve is installed on the second branch pipe before being connected to the second heat exchanger, and the second temperature sensor is installed on the second branch pipe after being connected to the second heat exchanger.

[0011] Furthermore, the heat exchange system also includes a gas purification system and a third branch pipe. The gas purification system is used to purify the hydrogen after it has been separated by the hydrogen separation system. The third branch pipe is connected in parallel with the first and second branch pipes, and the gas purification system is connected in series with the third branch pipe.

[0012] Furthermore, the gas purification system includes a third heat exchanger, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe is connected in sequence to the gas-liquid channels of the first and third heat exchangers, and the third branch pipe is connected to the cold source channel of the third heat exchanger.

[0013] Furthermore, the flow control system includes a third regulating valve and a third temperature sensor. The third regulating valve is electrically connected to the third temperature sensor. The third regulating valve is installed on the third branch pipe before it is connected to the third heat exchanger, and the third temperature sensor is installed on the third branch pipe after it is connected to the third heat exchanger.

[0014] Furthermore, the first, second, and third branch pipes are all equipped with gas leak monitoring systems. The leak monitoring system includes a detector and a fourth regulating valve. The detector is used to detect the concentration of hydrogen and oxygen in the pipeline, and the detector and the fourth regulating valve are electrically connected.

[0015] Beneficial effects: This application, through the installation of a cold source supply device, can simultaneously provide a cold source for both the hydrogen separation system and the oxygen separation system. Furthermore, the flow rate of the cold source medium input to both systems is controlled in real time via a flow control system, enabling thermal coupling between the two systems. This eliminates the phenomenon of heat cancellation and achieves thermodynamic balance, allowing the two separation processes to share a single cold source system. Simultaneously, it simplifies the overall system structure, reduces equipment investment costs, and lowers the energy consumption of system operation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the heat exchange system for proton membrane water electrolysis hydrogen production according to the present invention; Figure 2 This is a schematic diagram of the hydrogen separation system structure in the heat exchange system for hydrogen production via proton membrane water electrolysis, as described in this invention. Figure 3 This is a schematic diagram of the oxygen separation system in the heat exchange system for hydrogen production via proton membrane water electrolysis, as described in this invention. Figure 4 This is a schematic diagram of the gas purification system structure in the heat exchange system for hydrogen production via proton membrane water electrolysis, as described in this invention. Figure 5 This is a schematic diagram of the gas leakage monitoring system in the heat exchange system for hydrogen production via proton membrane water electrolysis, as described in this invention. Figure 6 A schematic diagram of a prior art separation system for separating low-temperature hydrogen and oxygen using a chiller; Figure 7 This is a schematic diagram of a separation system for separating high-temperature hydrogen using a cooling tower, based on existing technology. In the diagram: 1. Cold source supply equipment; 11. Pipeline; 12. First branch pipe; 13. Second branch pipe; 14. Third branch pipe; 2. Hydrogen separation system; 21. First heat exchanger; 22. First regulating valve; 23. First temperature sensor; 24. First shut-off valve; 3. Oxygen separation system; 31. Second heat exchanger; 32. Second regulating valve; 33. Second temperature sensor; 34. Second shut-off valve; 4. Hydrogen delivery pipe; 41. Hydrogen side of electrolyzer; 42. Client; 5. Oxygen delivery pipe; 51. Oxygen side of electrolyzer; 6. Gas purification system; 61. Third heat exchanger; 62. Third regulating valve; 63. Third temperature sensor; 64. Third shut-off valve; 7. Monitoring system; 71. Detector; 72. Fourth regulating valve.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0021] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the term "and / or" throughout the text includes three solutions; taking A and / or B as an example, it includes technical solution A, technical solution B, and a technical solution that simultaneously satisfies A and B. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0022] like Figure 1 As shown, this application provides a heat exchange system for proton membrane water electrolysis to produce hydrogen, including: a cold source supply device 1, which is used to generate a cold source medium; Hydrogen separation system 2, which is used to separate hydrogen from hydrogen gas-liquid mixture; Oxygen separation system 3, which is used to separate oxygen from an oxygen gas-liquid mixture; The cold source supply equipment 1 provides cold source medium to both the hydrogen separation system 2 and the oxygen separation system 3 through the pipeline 11, and the cold source medium flows back to the cold source supply equipment 1 after passing through the hydrogen separation system 2 and the oxygen separation system 3 respectively. The flow control system is used to regulate the flow rate of the cold source medium input to the hydrogen separation system 2 and the oxygen separation system 3 based on temperature feedback. Hydrogen delivery pipe 4, one end of which is connected to the hydrogen side 41 (GLSH) of the electrolyzer, and the other end is connected to the hydrogen separation system 2; Oxygen delivery pipe 5, one end of which is connected to the oxygen side 51 (GLSO) of the electrolytic cell, and the other end of which is connected to the oxygen separation system 3.

[0023] In this embodiment, the cold source supply equipment 1 is a cooling tower or a chiller. The hydrogen separation system 2 and the oxygen separation system 3 both adopt the form of heat exchange, so that hydrogen and oxygen are separated from the hydrogen gas-liquid mixture and oxygen gas-liquid mixture generated by the electrolysis of the PEM electrolyzer. The total cold source medium supply of the cold source supply equipment 1 is equal to or slightly greater than the total demand of each system. The hydrogen delivery pipe 4 delivers the gas-liquid mixture of hydrogen generated by the PEM electrolyzer to the hydrogen separation system 2 for separation and purification. The oxygen delivery pipe 5 delivers the gas-liquid mixture of oxygen generated by the PEM electrolyzer to the oxygen separation system 3 for separation and purification. The hydrogen separation system 2 is connected in series with the hydrogen delivery pipe 4, and the oxygen separation system 3 is connected in series with the oxygen delivery pipe 5. The other end of the hydrogen delivery pipe 4 is connected to the client 42, and the other end of the oxygen delivery pipe 5 is directly vented into the atmosphere. The cold source supply equipment 1 provides a cold source for both the hydrogen separation system 2 and the oxygen separation system 3. The flow rate of the cold source medium input to the hydrogen separation system 2 and the oxygen separation system 3 is controlled in real time through the set flow control system. This makes the thermodynamics of the hydrogen separation system 2 and the oxygen separation system 3 coupled, eliminates the phenomenon of heat cancellation, achieves thermodynamic balance of the system, and allows the two separation processes to share a cold source system. At the same time, it simplifies the overall structure and layout of the system, reduces equipment investment costs, and reduces the energy consumption of the system operation. After the cold source medium completes the heat exchange and removes heat, it flows back to the cold source supply equipment 1 for recooling and recycling. The entire system forms a closed loop, avoiding waste of the cold source medium and improving resource utilization. The separated and purified hydrogen and oxygen are also transported to the next process through the corresponding hydrogen delivery pipe 4 and oxygen delivery pipe 5.

[0024] In one embodiment, it further includes a first branch pipe 12 and a second branch pipe 13. The first branch pipe 11 and the second branch pipe 12 are connected in parallel and then connected in series with the pipeline 11. The hydrogen separation system 2 is connected in series with the pipeline 11 through the first branch pipe 12, and the oxygen separation system 3 is connected in series with the pipeline 11 through the second branch pipe 13.

[0025] In this embodiment, the cold source supply device 1 can simultaneously supply cold source medium to the hydrogen separation system 2 through the first branch pipe 12 and to the oxygen separation system 3 through the second branch pipe 13. After the cold source medium completes heat exchange in the two separation systems, it is then uniformly returned to the cold source supply device 1 through the pipeline 11. This not only realizes the layout of two separation systems sharing a cold source, but also ensures that the two cold source supplies do not interfere with each other through parallel pipelines, thus ensuring the temperature control stability of the two separation systems and avoiding the impact of temperature difference caused by series pipelines on the separation effect.

[0026] like Figures 2 to 5 As shown, in one embodiment, the hydrogen separation system 2 includes a first heat exchanger 21, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe 4 is connected to the gas-liquid channel of the first heat exchanger 21, and the first branch pipe 12 is connected to the cold source channel of the first heat exchanger 21.

[0027] In this embodiment, the hydrogen-liquid mixture output from the hydrogen side 41 (GLSH) of the electrolyzer enters the gas-liquid channel of the first heat exchanger 21 through the hydrogen delivery pipe 4. The cold source medium flows into the cold source channel through the first branch pipe 12. The two types of media complete heat exchange without contacting each other in the first heat exchanger 21. The liquid component of the hydrogen-liquid mixture precipitates out due to the decrease in solubility caused by the decrease in temperature, realizing efficient separation and subcooling of the gas and liquid phases, thereby separating the hydrogen. After cooling, it can be output to the next storage or purification process. The heated cold source medium flows back to the cold source supply equipment 1 for recooling, completing the cycle. In addition, a first shut-off valve 24 is installed on the hydrogen delivery pipe 4 and the first branch pipe 12, which are connected to both ends of the gas-liquid channel and both ends of the cold source channel of the first heat exchanger 21. The first shut-off valve 24 can quickly cut off the passage of the corresponding pipeline when the equipment is under maintenance or shut down due to failure, so as to avoid media leakage or affect the normal operation of other modules, improve the safety and convenience of system maintenance, and the sealing structure of the valve can be adapted to the low temperature conditions of the cold source medium. It can still maintain a reliable shut-off effect after long-term use, without the need to frequently replace the sealing components, thus reducing the maintenance cost of the system.

[0028] In one embodiment, the flow control system includes a first regulating valve 22 and a first temperature sensor 23. The first regulating valve 22 is electrically connected to the first temperature sensor 23. The first regulating valve 22 is disposed on a first branch pipe 12 before being connected to the first heat exchanger 21, and the first temperature sensor 23 is disposed on a first branch pipe 12 after being connected to the first heat exchanger 21.

[0029] In this embodiment, the first regulating valve 22 is a pneumatic regulating valve, and the first temperature sensor 23 monitors the temperature of the cold source medium after heat exchange in the first heat exchanger 21 in real time. When the detected temperature deviates from the set temperature control range, it will automatically send an adjustment signal to the first regulating valve 22 to adjust the opening of the first regulating valve 22, thereby changing the flow rate of the cold source medium in the first branch pipe 12, and then adjusting the heat exchange rate in the first heat exchanger 21, so as to stably control the hydrogen temperature at the outlet of the first heat exchanger 21 within the set range and ensure the stability of the hydrogen separation effect. A PID negative feedback closed-loop control is formed by the first regulating valve 22 and the first temperature sensor 23 to ensure that the outlet temperature of the cold source channel of the first heat exchanger 21 remains constant at a set threshold. Simultaneously, the first temperature sensor 23 integrates display and multi-level alarm functions, specifically four alarm thresholds corresponding to high alarm, high-high alarm, low alarm, and low-low alarm. When the temperature exceeds the corresponding threshold, an alarm will be triggered promptly, facilitating maintenance personnel to quickly troubleshoot abnormal operating conditions and preventing abnormal temperature fluctuations from affecting the subsequent hydrogen separation and purification effect, thus ensuring the stability and reliability of the entire heat exchange system. Furthermore, the thresholds are programmable to achieve fine-grained control of process parameters.

[0030] like Figure 3 As shown, in one embodiment, the oxygen separation system 3 includes a second heat exchanger 31, which has a gas-liquid channel and a cold source channel. The oxygen delivery pipe 5 is connected to the gas-liquid channel of the second heat exchanger 31, and the second branch pipe 13 is connected to the cold source channel of the second heat exchanger 31.

[0031] In this embodiment, the oxygen-liquid mixture output from the oxygen side 51 (GLSO) of the electrolytic cell enters the gas-liquid channel of the second heat exchanger 31 through the oxygen delivery pipe 5. The cold source medium flows into the cold source channel through the second branch pipe 13. The two types of media exchange heat without contacting each other in the second heat exchanger 31. The liquid component of the oxygen-liquid mixture precipitates out due to the decrease in solubility caused by the decrease in temperature, thereby achieving efficient separation and subcooling of the gas and liquid phases, thus separating the oxygen. After cooling, it can be output to the next storage or purification process or directly discharged into the air. The heated cold source medium flows back to the cold source supply equipment 1 for recooling, completing the cycle. In addition, a second shut-off valve 34 is installed on the oxygen delivery pipe 5 and the second branch pipe 13, which are connected to both ends of the gas-liquid passage and both ends of the cold source passage of the second heat exchanger 31. The second shut-off valve 34 can quickly cut off the passage of the corresponding pipeline when the equipment is under maintenance or shut down due to failure, so as to avoid media leakage or affect the normal operation of other modules, improve the safety and convenience of system maintenance, and the sealing structure of the valve can be adapted to the low temperature conditions of the cold source medium. It can still maintain a reliable shut-off effect after long-term use, without the need for frequent replacement of sealing components, thus reducing the maintenance cost of the system.

[0032] In one embodiment, the flow control system further includes a second regulating valve 32 and a second temperature sensor 33. The second regulating valve 32 is electrically connected to the second temperature sensor 33. The second regulating valve 32 is disposed on the second branch pipe 13 before being connected to the second heat exchanger 31, and the second temperature sensor 33 is disposed on the second branch pipe 13 after being connected to the second heat exchanger 31.

[0033] In this embodiment, the second regulating valve 32 is a pneumatic regulating valve, and the second temperature sensor 33 monitors the temperature of the cold source medium after heat exchange in the second heat exchanger 31 in real time. When the detected temperature deviates from the set temperature control range, it will automatically send an adjustment signal to the second regulating valve 32 to adjust the opening of the second regulating valve 32, thereby changing the flow rate of the cold source medium in the second branch pipe 13, and then adjusting the heat exchange rate in the second heat exchanger 31, so as to stably control the oxygen temperature at the outlet of the second heat exchanger 31 within the set range and ensure the stability of the oxygen separation effect. A PID negative feedback closed-loop control is formed by the second regulating valve 32 and the second temperature sensor 33 to ensure that the outlet temperature of the cold source channel of the second heat exchanger 31 remains constant at the set threshold. Simultaneously, the second temperature sensor 33 integrates display and multi-level alarm functions, specifically four alarm thresholds corresponding to high alarm, high-high alarm, low alarm, and low-low alarm. When the temperature exceeds the corresponding threshold, an alarm will be triggered promptly, facilitating maintenance personnel to quickly troubleshoot abnormal operating conditions and preventing abnormal temperature fluctuations from affecting the subsequent hydrogen separation and purification effect, thus ensuring the stability and reliability of the entire heat exchange system. Furthermore, the thresholds are programmable to achieve fine-grained control of process parameters.

[0034] like Figure 4 As shown, in one embodiment, the heat exchange system further includes a gas purification system 6 and a third branch pipe 14. The gas purification system 6 is used to purify the hydrogen after it has been separated by the hydrogen separation system 2. The third branch pipe 14 is connected in parallel with the first branch pipe 11 and the second branch pipe 12. The gas purification system 6 is connected in series with the pipe 11 through the third branch pipe 14.

[0035] In this embodiment, the flow control system can also control the flow rate of the cold source medium input to the gas purification system 6. After preliminary separation by the hydrogen separation system 2, the hydrogen is sent to the gas purification system 6 through the hydrogen delivery pipe 4 for purification, further removing liquid components from the hydrogen to obtain high-purity hydrogen that meets the usage standards. If the hydrogen has met the purity requirements, it can be directly delivered to the client 42 through the hydrogen delivery pipe 4.

[0036] In one embodiment, the gas purification system 6 includes a third heat exchanger 61, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe 4 is connected in sequence to the gas-liquid channel of the first heat exchanger 21 and the third heat exchanger 61, and the third branch pipe 14 is connected to the cold source channel of the third heat exchanger 61.

[0037] In this embodiment, after hydrogen undergoes gas-liquid separation in the hydrogen separation system 2, it enters the gas-liquid channel of the third heat exchanger 61 through the hydrogen delivery pipe 4. The cold source medium flows into the cold source channel of the third heat exchanger 61 through the third branch pipe 14. The two types of media exchange heat without contacting each other in the third heat exchanger 61, and are condensed again to further purify the hydrogen. The heated cold source medium is then returned to the cold source supply device 1 for recooling. In addition, a third shut-off valve 64 is installed on the hydrogen delivery pipe 4 and the third branch pipe 14, which are connected to both ends of the gas-liquid passage and both ends of the cold source passage of the third heat exchanger 61. The third shut-off valve 64 can quickly cut off the passage of the corresponding pipeline when the equipment is under maintenance or shut down due to failure, so as to avoid media leakage or affect the normal operation of other modules, improve the safety and convenience of system maintenance, and the sealing structure of the valve can be adapted to the low temperature conditions of the cold source medium. It can still maintain a reliable shut-off effect after long-term use, without the need for frequent replacement of sealing components, thus reducing the maintenance cost of the system.

[0038] In one embodiment, the flow control system further includes a third regulating valve 62 and a third temperature sensor 63. The third regulating valve 62 is electrically connected to the third temperature sensor 63. The third regulating valve 62 is disposed on the third branch pipe 14 before being connected to the third heat exchanger 61, and the third temperature sensor 63 is disposed on the third branch pipe 14 after being connected to the third heat exchanger 61.

[0039] In this embodiment, the third regulating valve 62 is a pneumatic regulating valve, and the third temperature sensor 63 monitors the temperature of the cold source medium after heat exchange in the third heat exchanger 61 in real time. When the detected temperature deviates from the set temperature control range, it will automatically send a regulating signal to the third regulating valve 62 to adjust the opening of the third regulating valve 62, thereby changing the flow rate of the cold source medium in the third branch pipe 14, and then adjusting the heat exchange rate in the third heat exchanger 61, so as to stably control the oxygen temperature at the outlet of the third heat exchanger 61 within the set range and ensure the stability of the oxygen separation effect. A PID negative feedback closed-loop control is formed by the third regulating valve 62 and the third temperature sensor 63 to ensure that the outlet temperature of the cold source channel of the third heat exchanger 61 remains constant at the set threshold. Simultaneously, the third temperature sensor 63 integrates display and multi-level alarm functions, specifically four alarm thresholds corresponding to high alarm, high-high alarm, low alarm, and low-low alarm. When the temperature exceeds the corresponding threshold, an alarm will be triggered promptly, facilitating maintenance personnel to quickly troubleshoot abnormal operating conditions and preventing abnormal temperature fluctuations from affecting the subsequent hydrogen separation and purification effect, thus ensuring the stability and reliability of the entire heat exchange system. Furthermore, the thresholds are programmable to achieve fine-grained control of process parameters.

[0040] like Figure 5 As shown, in one embodiment, the first branch pipe 12, the second branch pipe 13 and the third branch pipe 14 are all equipped with a gas leak monitoring system 7. The leak monitoring system 7 includes a detector 71 and a fourth regulating valve 72. The detector 71 is used to detect the concentration of hydrogen and oxygen in the pipeline. The detector 71 and the fourth regulating valve 72 are electrically connected.

[0041] In this embodiment, the gas leakage monitoring system 7 for each branch pipe is respectively installed after the first temperature sensor 23, the second temperature sensor 33, and the third temperature sensor 63, and the fourth regulating valve 72 is a pneumatic regulating valve. Detector 71 is used to detect the concentration of hydrogen and oxygen inside pipe 11; Detector 71 collects gas concentration data around each branch pipe in real time. When the concentration of hydrogen or oxygen exceeds the preset safety threshold, it determines that a gas leak has occurred in the pipeline. At this time, detector 71 will send a control signal to the fourth regulating valve 72 to control the fourth regulating valve 72 to close quickly, cut off the medium delivery of the corresponding branch, and prevent the leakage from continuing to expand. At the same time, it can trigger the safety alarm device in the plant area to remind the staff to come to the site in time to investigate and deal with the leak, and ensure the safe operation of the entire heat exchange hydrogen production system. By installing highly sensitive hydrogen and oxygen detectors 71 at each heat exchange node, the system can automatically isolate the faulty pipe section through the fourth regulating valve 72 in the early stage of leakage and before an explosive atmosphere is formed. This not only ensures the inherent safety of the system, but also greatly reduces the troubleshooting difficulty and downtime for maintenance personnel.

[0042] The heat exchange system for proton membrane water electrolysis hydrogen production in this application also has the following advantages: The original requirement of using a cooling tower and a chiller has been replaced by only one type of equipment. The equipment is evenly distributed and transported to the separation system through the first branch pipe 12, the second branch pipe 13 and the third branch pipe 14 respectively. The temperature difference after the sum of each branch is very small (less than 1℃), which does not affect the overall operation of the equipment unit. The equipment is streamlined and space is saved. Through clever pipeline design or composite heat exchange technology, the existing dual-unit technology is simplified into a single unit. This directly reduces the equipment footprint and makes the entire PEM system more compact. It is especially suitable for hydrogen refueling stations or distributed energy scenarios with strict space requirements. In particular, the currently popular single-unit outdoor independent operation mode, such as independent hydrogen refueling stations in the suburbs and independent hydrogen fueling stations on offshore platforms, has a space saving rate of at least 15% compared to the original layout. By sensing the temperature on each branch pipe and automatically adjusting the valve to match the real-time load of high-temperature heat dissipation (requiring cooling water) and low-temperature dehumidification (requiring chilled water) of the electrolytic cell, the overall energy efficiency ratio (COP) is greatly improved. The simplified control logic and improved anti-interference capabilities eliminate potential "cold and hot conflicts" that may have existed in the original two independent control systems. For example, if the cooling water temperature fluctuates, it will affect the gas heat exchange effect and directly affect the gas temperature when it enters the purification system (the temperature may be at the upper limit of the allowable temperature, which will inevitably affect the outlet water temperature of the chiller). In this invention, the return water temperature of the two branches can be set with relevant lock values, such as a maximum value of 1°C, so that the temperature difference can be effectively eliminated and the thermodynamic balance of the system can be made more stable.

[0043] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A heat exchange system for proton exchange membrane water electrolysis to produce hydrogen, characterized in that, include: A cold source supply device, wherein the cold source supply device is used to generate a cold source medium; A hydrogen separation system for separating hydrogen from a hydrogen gas-liquid mixture; An oxygen separation system for separating oxygen from an oxygen gas-liquid mixture; The cold source supply equipment provides the cold source medium to both the hydrogen separation system and the oxygen separation system through pipelines, and the cold source medium flows back to the cold source supply equipment after passing through the hydrogen separation system and the oxygen separation system respectively. A flow control system, wherein the flow control system is used to control the flow rate of the cold source medium input to the hydrogen separation system and the oxygen separation system based on temperature feedback; A hydrogen delivery pipe, one end of which is connected to the hydrogen side of the electrolyzer, and the other end of which is connected to the hydrogen separation system; An oxygen delivery pipe, one end of which is connected to the oxygen side of the electrolytic cell, and the other end of which is connected to the oxygen separation system.

2. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 1, characterized in that, It also includes a first branch pipe and a second branch pipe, which are connected in parallel and then in series with the pipeline. The hydrogen separation system is connected in series with the first branch pipe, and the oxygen separation system is connected in series with the second branch pipe.

3. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 2, characterized in that, The hydrogen separation system includes a first heat exchanger, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe is connected to the gas-liquid channel of the first heat exchanger, and the first branch pipe is connected to the cold source channel of the first heat exchanger.

4. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 3, characterized in that, The flow control system includes a first regulating valve and a first temperature sensor. The first regulating valve is electrically connected to the first temperature sensor. The first regulating valve is installed on the first branch pipe before it is connected to the first heat exchanger, and the first temperature sensor is installed on the first branch pipe after it is connected to the first heat exchanger.

5. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 2, characterized in that, The oxygen separation system includes a second heat exchanger, which has a gas-liquid channel and a cold source channel. The oxygen delivery pipe is connected to the gas-liquid channel of the second heat exchanger, and the second branch pipe is connected to the cold source channel of the second heat exchanger.

6. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 5, characterized in that, The flow control system includes a second regulating valve and a second temperature sensor. The second regulating valve is electrically connected to the second temperature sensor. The second regulating valve is installed on the second branch pipe before it is connected to the second heat exchanger, and the second temperature sensor is installed on the second branch pipe after it is connected to the second heat exchanger.

7. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 3, characterized in that, It also includes a gas purification system and a third branch pipe. The gas purification system is used to purify the hydrogen after it has been separated by the hydrogen separation system. The third branch pipe is connected in parallel with the first branch pipe and the second branch pipe, and the gas purification system is connected in series with the third branch pipe.

8. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 7, characterized in that, The gas purification system includes a third heat exchanger, which has a gas-liquid channel and a cold source channel. The hydrogen delivery pipe is connected in sequence to the gas-liquid channels of the first heat exchanger and the third heat exchanger. The third branch pipe is connected to the cold source channel of the third heat exchanger.

9. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 8, characterized in that, The flow control system includes a third regulating valve and a third temperature sensor. The third regulating valve is electrically connected to the third temperature sensor. The third regulating valve is installed on the third branch pipe before it is connected to the third heat exchanger, and the third temperature sensor is installed on the third branch pipe after it is connected to the third heat exchanger.

10. The heat exchange system for proton membrane water electrolysis hydrogen production according to claim 7, characterized in that, The first branch pipe, the second branch pipe, and the third branch pipe are all equipped with a gas leak monitoring system. The leak monitoring system includes a detector and a fourth regulating valve. The detector is used to detect the concentration of hydrogen and oxygen in the pipeline. The detector and the fourth regulating valve are electrically connected.

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