Hydrogen production method, system, device, medium and product integrating carbon dioxide heat pump

Abstract

The application discloses a hydrogen production method, system, equipment, medium and product integrated with a carbon dioxide heat pump, characterized in that the method is suitable for a hydrogen production system, and the hydrogen production system comprises a water vapor circulation module, an electrolysis reaction module and a supercritical carbon dioxide circulation module; water stored in a water collecting tank is pressurized by a water pump in the water vapor circulation module to obtain pressurized water, the pressurized water is subjected to heat exchange treatment based on target supercritical carbon dioxide working medium obtained by an air cooler in the water vapor circulation module to obtain heated water; the heated water is subjected to heat exchange treatment again by a high-temperature heat exchanger in the water vapor circulation module to obtain target water vapor; and the target water vapor is subjected to an electrochemical decomposition reaction by a solid oxide electrolysis cell in the electrolysis reaction module under the condition of continuous heating of the supercritical carbon dioxide circulation module to obtain hydrogen. The application can improve the hydrogen production efficiency of the solid oxide electrolysis cell under the condition of supercritical carbon dioxide high-temperature heat pump circulation.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology through water electrolysis, and in particular to hydrogen production methods, systems, equipment, media, and products using integrated carbon dioxide heat pumps. Background Technology

[0002] With the transformation of the energy structure, hydrogen energy, due to its advantages such as clean combustion products and large-scale storage and transportation, is considered an important carrier for building a future low-carbon energy system. Among them, water electrolysis for hydrogen production has the advantages of wide availability of raw materials and high purity of hydrogen produced, making it an important development direction in the current field of hydrogen energy production. Solid oxide electrolyzers (SOECs) can operate under high-temperature conditions and reduce the electrical energy input required for the electrolysis reaction by introducing heat energy, thus theoretically possessing higher energy conversion efficiency, making them a research hotspot for efficient hydrogen production technology. At the same time, solar thermal energy, as a clean and renewable form of thermal energy, has the characteristics of abundant resources and environmental friendliness. If it can be effectively coupled with the SOEC hydrogen production process, it is expected to reduce electricity consumption while achieving low-carbon and sustainable operation of the hydrogen production process.

[0003] However, existing SOEC hydrogen production systems still have significant shortcomings in terms of high-temperature heat source supply. On the one hand, traditional SOEC systems mostly use electric heating or fuel combustion to provide high-temperature heat. The former significantly increases the overall energy consumption of electrolytic hydrogen production, weakening the efficiency advantage of high-temperature electrolysis, while the latter introduces additional carbon emissions and system complexity, which is not conducive to achieving the goal of clean hydrogen production. On the other hand, solar thermal energy can usually only provide medium- and low-temperature heat energy, and its output has a certain degree of fluctuation and instability, making it difficult to directly meet the needs of SOEC at 700°C. The long-term, stable demand for high-quality heat sources at 900℃ leads to low thermal energy utilization efficiency. Furthermore, the coupling methods between solar thermal energy and SOEC in existing technologies are relatively simple, with limited capacity to improve heat quality, making it difficult to ensure stable high-temperature heat source supply while simultaneously achieving high energy utilization efficiency and controlling operating costs. Summary of the Invention

[0004] This invention provides a hydrogen production method, system, equipment, medium, and product integrating a carbon dioxide heat pump, which can improve the hydrogen production efficiency of solid oxide electrolyzers under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0005] In a first aspect, embodiments of the present invention provide a hydrogen production method integrating a carbon dioxide heat pump, applicable to a hydrogen production system, the hydrogen production system comprising: a water vapor circulation module, an electrolysis reaction module, and a supercritical carbon dioxide circulation module; The water stored in the water collection tank is pressurized by the water pump in the steam circulation module to obtain pressurized water. The pressurized water is then subjected to heat exchange treatment based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. The heated water is subjected to another heat exchange process through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. Hydrogen gas is obtained by electrochemically decomposing the target water vapor in the solid oxide electrolytic cell of the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide circulation module.

[0006] In this embodiment of the invention, a water pump in the steam circulation module pressurizes the water stored in the water collection tank, maintaining the water in a stable liquid phase state during subsequent heating, thereby improving heat exchange driving force and efficiency. Simultaneously, the target supercritical carbon dioxide working fluid in the air cooler exchanges heat with the pressurized water, ensuring that the heat released during the supercritical carbon dioxide cycle is fully recovered and transferred to the water side, thus achieving cascaded utilization of thermal energy, reducing system heat loss, and improving the hydrogen production efficiency of the solid oxide electrolysis cell under supercritical carbon dioxide high-temperature heat pump cycle conditions. The high-temperature heat exchanger in the steam circulation module further heats the heated water, causing it to absorb heat and undergo vaporization, obtaining the required solid oxygen. The high-temperature target steam required for the operation of the solid oxide electrolyzer improves the quality and reactivity of the steam entering the electrolyzer, reduces the electrical work input required for the electrolysis process, and enhances the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump circulation conditions. Through the solid oxide electrolyzer in the electrolysis reaction module, under the continuous heating condition of the supercritical carbon dioxide circulation module, the electrolyzer is maintained in a stable high-temperature operating state, allowing the steam to undergo electrochemical decomposition reactions at high temperatures. This reduces the electrical energy consumption of the reaction and increases the electrolysis conversion rate, achieving synergistic coupling utilization of thermal and electrical energy, and further enhancing the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump circulation conditions.

[0007] Furthermore, the process of using the target supercritical carbon dioxide working fluid obtained from the air cooler in the steam circulation module to perform heat exchange treatment on the pressurized water to obtain heated water includes: The target supercritical carbon dioxide working fluid is introduced into the hot end channel of the air cooler through the hot end inlet of the steam circulation module for flow treatment, so as to obtain the flowing supercritical carbon dioxide working fluid. The pressurized water is introduced into the cold end channel of the air cooler through the cold end inlet of the steam circulation module for flow treatment, thus obtaining flowing pressurized water. The first heat exchange wall of the air cooler performs countercurrent heat exchange between the flowing supercritical carbon dioxide working fluid and the flowing pressurized water, so as to raise the temperature of the flowing pressurized water by the heat energy released by the flowing supercritical carbon dioxide working fluid, thereby obtaining heated water.

[0008] This invention introduces the target supercritical carbon dioxide working fluid and pressurized water into the hot-end and cold-end flow channels of the gas cooler, respectively, to form a stable counter-current flow state, thereby improving the utilization rate of heat exchange temperature difference and the driving force of heat transfer. Furthermore, it achieves efficient heat transfer through the first heat exchange wall, ensuring that the heat energy released by the supercritical carbon dioxide working fluid is fully recovered and transferred to the water side. This enables rapid heating of the pressurized water and tiered utilization of heat, thereby reducing the overall heat loss of the system and providing a stable heat source for subsequent high-temperature steam generation. This improves the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0009] Furthermore, the step of further heat-exchanging the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam includes: The heated water is introduced into the cold end channel of the high-temperature heat exchanger through the cold end inlet of the high-temperature heat exchanger in the steam circulation module for flow treatment, so as to obtain flowing heated water. Electrolytic gas output from the solid oxide electrolysis cell is introduced into the hot end channel of the high-temperature heat exchanger through the hot end inlet of the high-temperature heat exchanger in the steam circulation module for flow treatment, thereby obtaining flowing electrolytic gas. The second heat exchange wall of the high-temperature heat exchanger performs convective heat exchange on the flowing heated water and the flowing electrolytic gas, so as to vaporize the flowing heated water through the heat released by the flowing electrolytic gas to obtain the target water vapor.

[0010] In this embodiment of the invention, heated water and high-temperature electrolytic gas output from the solid oxide electrolysis cell are introduced into the cold-end and hot-end channels of a high-temperature heat exchanger, respectively, to form a convective heat exchange process, thereby realizing the recovery and utilization of waste heat from the electrolysis tail gas. The heat released by the electrolytic gas is transferred to the heated water side through the second heat exchange wall, allowing the heated water to vaporize and obtain the target water vapor that meets the requirements of electrolysis. This reduces the external heating demand, improves the system's thermal energy utilization rate, and can improve the hydrogen production efficiency of the solid oxide electrolysis cell under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0011] Furthermore, the supercritical carbon dioxide cycle module includes: a carbon dioxide compressor, an air cooler, a solar collector, and a low-pressure side regulating submodule; The first supercritical carbon dioxide working fluid is obtained by absorbing heat and raising the temperature of the pre-charged supercritical carbon dioxide working fluid through the solar collector. The first supercritical carbon dioxide working fluid is compressed and heated by the carbon dioxide compressor to obtain the second supercritical carbon dioxide working fluid. The second supercritical carbon dioxide working fluid is subjected to heat exchange treatment by the air cooler to transfer the heat released by the second supercritical carbon dioxide working fluid to the water vapor circulation module, so as to obtain the third supercritical carbon dioxide working fluid. The third supercritical carbon dioxide working fluid is depressurized and expanded by the low-pressure side regulation submodule to obtain the fourth supercritical carbon dioxide working fluid. The fourth supercritical carbon dioxide working fluid is then transported to the solar collector for heat absorption again to form a closed loop, thus obtaining the target supercritical carbon dioxide working fluid for continuously providing heat energy to the water vapor circulation module.

[0012] This invention utilizes a solar collector to absorb heat and raise the temperature of supercritical carbon dioxide working fluid, combined with the compression and heating effect of a carbon dioxide compressor, to improve the working fluid's temperature and enthalpy level. Subsequently, a gas cooler transfers high-grade heat energy to a steam circulation module, achieving effective heat output. Then, a low-pressure side regulating submodule completes pressure reduction and expansion, returning the heat to the solar collector to form a closed-loop heat pump cycle. This constructs a stable and continuous high-temperature heating path, improving the system's heat quality and utilization rate, and enhancing the hydrogen production efficiency of a solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0013] Furthermore, the process of depressurizing and expanding the third supercritical carbon dioxide working fluid through the low-pressure side regulating submodule to obtain the fourth supercritical carbon dioxide working fluid includes: The third supercritical carbon dioxide working fluid is subjected to internal heat exchange treatment through an internal heat exchanger to obtain a preheated supercritical carbon dioxide working fluid. The preheated supercritical carbon dioxide working fluid is throttled and depressurized using a throttling valve to obtain a depressurized supercritical carbon dioxide working fluid. The supercritical carbon dioxide working fluid is expanded and subjected to work by a carbon dioxide expander to obtain the fourth supercritical carbon dioxide working fluid. The low-pressure side regulating submodule includes the internal heat exchanger, the throttling valve and the carbon dioxide expander.

[0014] This invention utilizes an internal heat exchanger to recover energy and optimize the temperature of the third supercritical carbon dioxide working fluid, thereby improving the heat utilization rate within the cycle. Pressure regulation is achieved through a throttling valve, and a carbon dioxide expander is used to expand and recover some mechanical energy, thus reducing cycle power consumption and stabilizing the low-pressure side operation. Ultimately, this forms a closed-loop cycle with reasonable parameter matching, which can improve the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0015] Furthermore, the steam circulation module also includes: a steam condenser, a gas-liquid separator, and a hydrogen storage device; The electrolytic gas output from the solid oxide electrolytic cell is condensed by the steam condenser to obtain a condensed mixed fluid; The condensed mixed fluid is subjected to gas-liquid separation treatment by the gas-liquid separator to obtain liquid water and hydrogen. The liquid water and hydrogen are recovered and stored through the water collection tank and the hydrogen storage device to obtain circulating water and target hydrogen respectively.

[0016] This invention utilizes a steam condenser to condense the electrolytic gas, effectively recovering unreacted water vapor; a gas-liquid separator to efficiently separate liquid water and hydrogen, improving hydrogen purity; and a water collection tank and a hydrogen storage device to recover and store water and hydrogen respectively, forming a closed-loop water resource cycle and a stable hydrogen output mechanism. This reduces water consumption and heat loss, improves the overall energy utilization rate of the system, and enhances the hydrogen production efficiency of solid oxide electrolyzers under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0017] Secondly, embodiments of the present invention provide a hydrogen production system integrating a carbon dioxide heat pump, the system comprising: a preheating module, a heat exchange module, and a hydrogen production module; The preheating module is used to pressurize the water stored in the water collection tank through the water pump in the steam circulation module to obtain pressurized water. The pressurized water is then subjected to heat exchange treatment based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. The heat exchange module is used to further heat the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. The hydrogen production module is used to electrochemically decompose the target water vapor through the solid oxide electrolysis cell in the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide cycle module to obtain hydrogen.

[0018] This invention utilizes a preheating module to pressurize and initially heat water, improving heat exchange efficiency and fully utilizing the high-grade thermal energy output from the supercritical carbon dioxide cycle. The heat exchange module further recovers waste heat from electrolysis and completes water vaporization, improving steam quality and thermal energy utilization. The hydrogen production module performs high-temperature electrochemical decomposition under continuous and stable heating conditions, reducing electrolysis power consumption and improving conversion efficiency. This constructs a highly efficient hydrogen production system coupled with a heat pump, enhancing the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0019] Thirdly, embodiments of the present invention provide a terminal device, including: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other through the communication bus; The memory is used to store at least one executable instruction that causes the processor to perform the operation of the hydrogen production method of the integrated carbon dioxide heat pump as described in this application.

[0020] Fourthly, embodiments of the present invention provide a computer-readable storage medium comprising a stored computer program, wherein, when the computer program is executed, it controls the device or system where the computer-readable storage medium is located to perform a hydrogen production method using an integrated carbon dioxide heat pump as described in this application.

[0021] Based on the above-described method embodiments, another embodiment of the present invention provides a computer program product, including a computer program or instructions, which, when executed by a communication device, implements the hydrogen production method of the integrated carbon dioxide heat pump of any embodiment of the present invention.

[0022] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic flowchart of an embodiment of the hydrogen production method using an integrated carbon dioxide heat pump provided in this application. Figure 2This is a schematic diagram of the hydrogen production system with an integrated carbon dioxide heat pump provided in this application; Figure 3 This is a schematic diagram of an embodiment of the hydrogen production method using an integrated carbon dioxide heat pump provided in this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. 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.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0027] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0028] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0029] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0030] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0031] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0032] With the transformation of the energy structure, hydrogen energy has become an important energy carrier due to its clean and low-carbon nature. Water electrolysis for hydrogen production, especially solid oxide electrolyzers (SOECs), has become a key direction for efficient hydrogen production due to its advantages such as high-temperature operation and the ability to introduce heat energy to reduce power consumption. Solar thermal energy, as a clean and renewable heat source, can help reduce electricity consumption and achieve low-carbon operation if effectively coupled with SOECs. However, existing SOEC systems mostly rely on electric heating or fuel combustion for heat supply, resulting in high energy consumption and carbon emissions. Solar thermal energy, on the other hand, has a low temperature grade and fluctuating output, making it difficult to stably meet high-temperature requirements. Furthermore, existing coupling methods have limited heat enhancement capabilities, hindering improvements in system efficiency and economics.

[0033] See Figure 1 To improve the hydrogen production efficiency of a solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions, an embodiment of the present invention provides a hydrogen production method with an integrated carbon dioxide heat pump, which is applicable to a hydrogen production system. The hydrogen production system includes a water vapor cycle module, an electrolysis reaction module and a supercritical carbon dioxide cycle module, including steps S101 to S103. For ease of understanding, Figure 2This is a schematic diagram of the structure of the integrated carbon dioxide heat pump hydrogen production system provided in this application. The integrated carbon dioxide heat pump hydrogen production system includes: a solid oxide electrolysis cell (1), a high-temperature heat exchanger (2), a water vapor condenser (3), a gas-liquid separator (4), a hydrogen storage device (5), a water collection tank (6), a water pump (7), a gas cooler (8), an internal heat exchanger (9), a carbon dioxide compressor (10), a throttle valve (11), a carbon dioxide expander (12), and a solar collector (13). In the water vapor circulation module, water is stored in a water collection tank (6). The outlet of the water collection tank (6) is connected to the inlet of a water pump (7) through a pipeline. The outlet of the water pump (7) is connected to the cold end inlet of the air cooler (8). After being pressurized by the water pump (7), the water enters the cold end of the air cooler (8). After absorbing the heat released by the supercritical carbon dioxide working fluid at its hot end in the air cooler (8), the water flows out from the cold end outlet of the air cooler (8) and enters the cold end inlet of the high-temperature heat exchanger (2). After being preheated by the air cooler (8), the water further exchanges heat with the high-temperature electrolysis product gas from the outlet of the solid oxide electrolysis cell (1) in the high-temperature heat exchanger (2). After that, the water flows out from the cold end outlet of the high-temperature heat exchanger (2) and enters the inlet of the solid oxide electrolysis cell (1). In the solid oxide electrolysis cell (1) of the electrolysis reaction module, the high-temperature water vapor that enters undergoes an electrochemical decomposition reaction under the combined action of electrical energy and external heating to generate a mixed gas of hydrogen and unreacted water vapor. This mixed gas flows out from the outlet of the solid oxide electrolysis cell (1) and enters the hot end inlet of the high-temperature heat exchanger (2). After releasing some heat in the high-temperature heat exchanger (2), it flows out from its hot end outlet and enters the hot end inlet of the water vapor condenser (3). The mixed gas is further cooled in the water vapor condenser (3), where the water vapor is condensed into liquid water and flows into the gas-liquid separator (4) through the hot end outlet of the water vapor condenser (3). In the gas-liquid separator (4), the liquid water flows back to the water collection tank (6) through the lower outlet, while the hydrogen enters the hydrogen storage device (5) through the upper outlet for collection and storage, thereby forming a closed loop of water-steam-hydrogen.In the supercritical carbon dioxide circulation module, the low-temperature supercritical carbon dioxide working fluid first flows out from the cold end outlet of the internal heat exchanger (9) and enters the inlet of the carbon dioxide compressor (10). After being compressed by the carbon dioxide compressor (10), it enters the hot end inlet of the air cooler (8) from its outlet. The high-temperature and high-pressure supercritical carbon dioxide working fluid exchanges heat with the water at the cold end in the air cooler (8) and then flows out from the hot end outlet of the air cooler (8) and enters the hot end inlet of the internal heat exchanger (9). In the internal heat exchanger (9), the high-temperature carbon dioxide working fluid exchanges heat with the low-temperature working fluid from the solar collector (13) and then flows out from the hot end outlet of the internal heat exchanger (9). The supercritical carbon dioxide working fluid flows out and enters the inlet of the throttle valve (11); after being depressurized by the throttle valve (11), it enters the inlet of the carbon dioxide expander (12), expands and does work in the carbon dioxide expander (12), and then flows out from its outlet and enters the inlet of the solar collector (13); after absorbing solar radiation heat in the solar collector (13), the supercritical carbon dioxide working fluid flows out from its outlet and enters the cold end inlet of the internal heat exchanger (9), and after exchanging heat with the high-temperature working fluid from the air cooler (8) in the internal heat exchanger (9), it returns to the inlet of the carbon dioxide compressor (10) through the cold end outlet of the internal heat exchanger (9), completing the closed supercritical carbon dioxide heat pump cycle. Through the coupled operation of the above two circulation loops, the air cooler (8) and the high-temperature heat exchanger (2) serve as heat exchange nodes between the carbon dioxide loop and the water vapor loop, respectively, realizing the continuous supply of high-quality heat energy after the solar thermal energy is boosted by the supercritical carbon dioxide heat pump to the solid oxide electrolyzer (1), thereby ensuring the stable operation of the electrolyzer and realizing efficient hydrogen production.

[0034] Step S101: Pressurize the water stored in the water collection tank by the water pump in the water vapor circulation module to obtain pressurized water. Then, perform heat exchange treatment on the pressurized water based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the water vapor circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. In some embodiments, the water stored in the water collection tank is pressurized by the water pump in the water vapor circulation module to obtain pressurized water. Specifically, the initial temperature of the liquid water stored in the water collection tank (6) is 15°C. 40 The pressure is normal (around 0.1 MPa). After water is drawn in by the water pump (7), it undergoes mechanical pressurization under the drive of the motor, raising the water pressure to 0.5 MPa. 3.0 MPa, preferably 1.0 MPa. 2.5 MPa. This pressure range is higher than the saturated vapor pressure at the corresponding temperature to ensure that the water remains in a liquid or superheated liquid state during subsequent heating, avoiding premature vaporization in the air cooler (8) and affecting heat exchange stability. The water temperature after pressurization is basically maintained at 20°C. 60 Between them, the water is continuously output from the outlet of the water pump (7) and transported through the pressure-resistant pipeline to the cold end inlet of the air cooler (8), forming a stable high-pressure liquid water flow.

[0035] In some embodiments, the heat exchange treatment of the pressurized water based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water includes: introducing the target supercritical carbon dioxide working fluid into the hot-end flow channel of the air cooler through the hot-end inlet of the air cooler in the steam circulation module for flow treatment to obtain flowing supercritical carbon dioxide working fluid; introducing the pressurized water into the cold-end flow channel of the air cooler through the cold-end inlet of the air cooler in the steam circulation module for flow treatment to obtain flowing pressurized water; and performing countercurrent heat exchange treatment on the flowing supercritical carbon dioxide working fluid and the flowing pressurized water based on the first heat exchange wall surface of the air cooler, so as to raise the temperature of the flowing pressurized water by the heat energy released by the flowing supercritical carbon dioxide working fluid to obtain heated water.

[0036] In some embodiments, the target supercritical carbon dioxide working fluid is introduced into the hot-end flow channel of the air cooler through the hot-end inlet of the steam circulation module for flow processing to obtain a flowing supercritical carbon dioxide working fluid. Specifically, the target supercritical carbon dioxide working fluid is compressed by the supercritical carbon dioxide circulation module and output by the compressor (10), with a pressure range of 7.5. 12MPa, preferably 8 10 MPa, higher than the critical pressure of carbon dioxide 7.38 MPa; its temperature range is 400°C. 750 500 is preferred 700 It is above the critical temperature of 31.1°C. This ensures that the working fluid is always in a supercritical state. The high-temperature and high-pressure supercritical carbon dioxide working fluid enters the hot end inlet of the gas cooler (8) through a closed high-pressure pipeline and flows continuously in the hot end flow channel in a preset direction. In the hot end flow channel, the supercritical carbon dioxide maintains a single-phase supercritical fluid state and does not undergo gas-liquid phase change. It transfers heat to the cold end side in the form of stable release of sensible heat, forming a flowing supercritical carbon dioxide working fluid.

[0037] In some embodiments, pressurized water is introduced into the cold-end flow channel of the air cooler through the cold-end inlet of the steam circulation module for flow treatment to obtain flowing pressurized water. Specifically, pressurized water output by the water pump (7) enters the cold-end inlet of the air cooler (8) through a pressure-resistant pipeline and enters the cold-end flow channel, which is isolated from the hot-end flow channel. The air cooler (8) is preferably a plate heat exchanger or a microchannel heat exchanger structure. The hot-end flow channel and the cold-end flow channel are sealed and isolated by a metal heat exchange wall to prevent direct contact between supercritical carbon dioxide and water. The pressurized water in the cold-end flow channel is at 0.5 Under a pressure of 3.0 MPa, the water flows in the opposite direction to the hot-end flow channel, forming a counter-current heat exchange structure and improving the efficiency of temperature difference utilization. The pressurized water remains in a liquid or near-saturated liquid state in the cold-end flow channel, forming a stable flow of pressurized water.

[0038] In some embodiments, the flowing supercritical carbon dioxide working fluid and the flowing pressurized water undergo countercurrent heat exchange based on the first heat exchange wall of the air cooler, so as to raise the temperature of the flowing pressurized water by the heat energy released by the flowing supercritical carbon dioxide working fluid, thereby obtaining heated water. Specifically, the temperature of the flowing supercritical carbon dioxide working fluid gradually decreases along the flow direction in the hot end channel, from 400°C at the inlet. 750 Gradually reduce to 250 500 During this process, the high-grade heat energy carried by the water is transferred through the first heat exchange wall to the pressurized water flowing in the cold-end channel via conduction. The pressurized water on the cold-end side continuously absorbs heat released from the supercritical carbon dioxide working fluid in a counter-current state, and the water temperature rises from 20°C. 60 Gradually increase to 150 350 Preferred to be increased to 200 300 Meanwhile, at the 0.5 It remains in a liquid state or forms a high-temperature, high-pressure water state under a pressure of 3.0 MPa. After heat exchange, the cooled supercritical carbon dioxide working fluid flows out from the hot end outlet of the gas cooler (8) and enters the internal heat exchanger (9) for further heat recovery; while the water heated in the first stage flows out from the cold end outlet of the gas cooler (8), forming heated water, and enters the high-temperature heat exchanger (2) for the second stage of waste heat heating treatment, so that it finally reaches 500. 800 High-temperature water vapor is formed before entering the solid oxide electrolysis cell (1). In this embodiment, the total heat transfer efficiency of the air cooler (8) is not less than 80%, preferably not less than 85%, so as to ensure that the high-temperature heat provided by the supercritical carbon dioxide cycle can be efficiently transferred to the water vapor cycle module, thereby providing a stable heat source for the solid oxide electrolysis cell (1) continuously.

[0039] Through the above steps, water is pressurized and preheated in stages, enabling it to fully absorb the high-grade heat energy released by supercritical carbon dioxide under stable high-pressure liquid conditions. At the same time, the counter-current heat exchange structure improves the heat transfer driving force and heat exchange efficiency, realizing the cascade utilization of heat and reducing system heat loss. This provides a stable heat source for subsequent high-temperature steam generation and can improve the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0040] Step S102: The heated water is subjected to heat exchange again through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. In some embodiments, the step of further heat-exchanging the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam includes: introducing the heated water into the cold-end flow channel of the high-temperature heat exchanger through the cold-end inlet of the steam circulation module to obtain flowing heated water; introducing the electrolytic gas output from the solid oxide electrolysis cell into the hot-end flow channel of the high-temperature heat exchanger through the hot-end inlet of the steam circulation module to obtain flowing electrolytic gas; and performing convective heat exchange on the flowing heated water and the flowing electrolytic gas based on the second heat exchange wall of the high-temperature heat exchanger, so as to vaporize the flowing heated water through the heat released by the flowing electrolytic gas to obtain the target steam.

[0041] In some embodiments, the heated water is introduced into the cold end channel of the high-temperature heat exchanger through the cold end inlet of the steam circulation module for flow treatment to obtain flowing heated water. Specifically, the heated water after the first stage heat exchange in the air cooler (8) flows out from the cold end outlet of the air cooler (8), and its temperature range is 150°C. 350 200 is preferred 300 The pressure is maintained at 0.5. 3.0 MPa, preferably 1.0 MPa. 2.5MPa. The heated water enters the cold end inlet of the high-temperature heat exchanger (2) through a high-temperature and pressure resistant pipeline, and then enters the cold end flow channel inside the high-temperature heat exchanger (2). The high-temperature heat exchanger (2) is preferably a high-temperature plate heat exchanger, a shell-and-tube heat exchanger, or a microchannel heat exchanger, and its material can be high-temperature resistant stainless steel or nickel-based alloy material to adapt to 700 The above describes the long-term operating environment. Within the cold-end flow channel, the heated water flows continuously in a preset direction, with the flow rate preferably controlled at 0.5. Within a speed range of 5 m / s, the convective heat transfer coefficient is kept within the design requirements while avoiding excessive pressure drop. At this point, the heating water remains liquid or in a high-pressure saturated state, providing stable conditions for subsequently absorbing the heat released by the high-temperature electrolytic gas and completing the phase change process.

[0042] In some embodiments, the electrolytic gas output from the solid oxide electrolysis cell is introduced into the hot-end flow channel of the high-temperature heat exchanger through the hot-end inlet of the high-temperature heat exchanger in the steam circulation module for flow treatment to obtain flowing electrolytic gas. Specifically, the operating temperature range of the solid oxide electrolysis cell (1) is 700°C. 900 750 is preferred. 850 The electrolytic gas generated during electrolysis is a mixture of hydrogen and incompletely reacted water vapor. Its outlet temperature is essentially the same as the operating temperature of the electrolytic cell, which is 700°C. 900 The pressure is typically 0.1. 0.5 MPa. The electrolytic gas flows out of the electrolytic cell (1) and enters the hot end inlet of the high-temperature heat exchanger (2) through a high-temperature resistant pipeline, and flows continuously in the hot end channel. The hot end channel and the cold end channel are sealed and isolated by a second heat exchange wall to prevent the gas from coming into direct contact with water. The electrolytic gas flows in the hot end channel in the opposite direction to the cold end channel, preferably forming a counter-current heat exchange structure to improve the logarithmic mean temperature difference and enhance the heat exchange efficiency. During the flow, the electrolytic gas remains in a gaseous state and does not liquefy, and its sensible heat and part of its latent heat serve as the main sources of heat release.

[0043] In some embodiments, convective heat exchange is performed on the flowing heated water and the flowing electrolytic gas based on the second heat exchange wall of the high-temperature heat exchanger, so that the flowing heated water is vaporized by the heat released by the flowing electrolytic gas to obtain the target water vapor. Specifically, the flowing electrolytic gas flows from an inlet temperature of 700°C in the hot end channel. 900 Gradually decrease to 300 600 The high-temperature sensible heat released is transferred to the flowing heated water in the cold-end channel through the second heat exchange wall via thermal conduction. After absorbing heat, the temperature of the flowing heated water increases from 150°C. 350 Gradually increase the pressure to the saturation temperature at the corresponding pressure; for example, the saturation temperature at 1.0 MPa is approximately 180°C. The saturation temperature at 2.0 MPa is approximately 212°C. Once the temperature reaches saturation, the heated water begins a phase change and absorbs heat, gradually transforming from a liquid to saturated steam. Upon continued heat absorption, it forms superheated steam, with an outlet temperature reaching 500°C. 800 The preferred value is 650. 800 During this process, the heat exchange efficiency of the high-temperature heat exchanger (2) is not less than 80%, preferably not less than 85%, thereby ensuring that the waste heat of the electrolytic gas is fully recovered and utilized. The final target water vapor pressure is maintained at 0.5. Within the range of 3.0 MPa, the gas enters the inlet of the solid oxide electrolytic cell (1) through a high-temperature pipeline, providing high-temperature steam reactants for the next round of electrolysis. Simultaneously, the temperature of the electrolytic gas after heat exchange is reduced to 300 °C. 600 The water then enters the steam condenser (3) for further cooling and condensation separation. Through the above two-stage heat exchange process (first-stage heating of the air cooler + second-stage vaporization and superheating of the high-temperature heat exchanger), a step-by-step heating path from room temperature liquid to high-temperature superheated steam is achieved, effectively utilizing the high-grade heat provided by the supercritical carbon dioxide cycle and the waste heat of the electrolytic gas, ensuring that the solid oxide electrolysis cell operates at 700°C. 900 It can operate stably for a long time under certain conditions.

[0044] In some embodiments, the supercritical carbon dioxide circulation module includes: a carbon dioxide compressor, an air cooler, a solar collector, and a low-pressure side regulating submodule; the solar collector absorbs heat and raises the temperature of pre-charged supercritical carbon dioxide working fluid to obtain a first supercritical carbon dioxide working fluid; the carbon dioxide compressor compresses and raises the temperature of the first supercritical carbon dioxide working fluid to obtain a second supercritical carbon dioxide working fluid; the air cooler performs heat exchange treatment on the second supercritical carbon dioxide working fluid to transfer the heat released by the second supercritical carbon dioxide working fluid to the steam circulation module to obtain a third supercritical carbon dioxide working fluid; the low-pressure side regulating submodule depressurizes and expands the third supercritical carbon dioxide working fluid to obtain a fourth supercritical carbon dioxide working fluid, and the fourth supercritical carbon dioxide working fluid is then transported back to the solar collector for heat absorption treatment to form a closed loop, obtaining a target supercritical carbon dioxide working fluid for continuously providing heat energy to the steam circulation module.

[0045] In some embodiments, the solar collector is used to absorb heat and raise the temperature of a pre-charged supercritical carbon dioxide working medium to obtain a first supercritical carbon dioxide working medium. Specifically, the carbon dioxide working medium is a working medium pre-charged in a closed circulation pipeline, and its initial state is a supercritical state with a pressure range of 7.5. 12MPa, preferably 8 10MPa, temperature range of 80 200 The expanded, low-temperature supercritical carbon dioxide working fluid enters the inlet of the solar collector (13) and absorbs solar thermal energy under the action of solar radiation. The solar collector (13) can be a trough collector or a tower collector, with an outlet temperature range of 250°C. 400 300 is preferred 380 During the endothermic process, the supercritical carbon dioxide working fluid remains in a single-phase supercritical state, and its temperature decreases from 80°C. 200 Increased to 250 400 The pressure remained basically at 7.5. Within the range of 10 MPa. The working fluid, after absorbing heat and heating up, flows out from the outlet of the solar collector (13) to obtain the first supercritical carbon dioxide working fluid.

[0046] In some embodiments, the first supercritical carbon dioxide working fluid is compressed and heated by the carbon dioxide compressor to obtain a second supercritical carbon dioxide working fluid. Specifically, the first supercritical carbon dioxide working fluid enters the inlet of the carbon dioxide compressor (10) from the cold end outlet of the internal heat exchanger (9). The compressor adopts a centrifugal compressor or an axial flow compressor structure. During the compression process, the working fluid pressure is increased from 7.5... 10 MPa increased to 9 12MPa, preferably 10 11MPa; temperature under adiabatic compression effect from 250 400 Further increase to 450 650 500 is preferred 600 The compressed working fluid remains in a supercritical state, and its enthalpy value is significantly increased. It flows out from the outlet of the compressor (10) to obtain the second supercritical carbon dioxide working fluid.

[0047] In some embodiments, the second supercritical carbon dioxide working fluid is subjected to heat exchange treatment through the air cooler to transfer the heat released by the second supercritical carbon dioxide working fluid to the steam circulation module to obtain a third supercritical carbon dioxide working fluid. Specifically, the second supercritical carbon dioxide working fluid enters the hot-end flow channel through the hot-end inlet of the air cooler (8) and undergoes indirect countercurrent heat exchange with the pressurized water delivered by the water pump (7) in the cold-end flow channel. During the heat exchange process, the temperature of the second supercritical carbon dioxide working fluid changes from 450°C to 450°C. 650 Gradually reduce to 250 400 The pressure remains at 9 Within the 12MPa range, it remains in a supercritical state. The heat released is transferred to the steam circulation module through the heat exchange wall, raising the cold end water temperature to 150°C. 350 After heat exchange, the supercritical carbon dioxide working fluid flows out from the hot end outlet of the gas cooler (8) to obtain the third supercritical carbon dioxide working fluid.

[0048] In some embodiments, the third supercritical carbon dioxide working fluid is depressurized and expanded through the low-pressure side regulating submodule to obtain a fourth supercritical carbon dioxide working fluid. The fourth supercritical carbon dioxide working fluid is then transported back to the solar collector for heat absorption to form a closed loop, resulting in a target supercritical carbon dioxide working fluid for continuously providing heat energy to the steam circulation module. Specifically, the low-pressure side regulating submodule includes an internal heat exchanger (9), a throttle valve (11), and a carbon dioxide expander (12). The third supercritical carbon dioxide working fluid first enters the hot end of the internal heat exchanger (9) and undergoes convective heat exchange with the low-temperature working fluid from the expander outlet, with the temperature decreasing from 250°C. 400 Reduced to 200 320 The pre-cooled working fluid is obtained; then the pre-cooled working fluid enters the throttling valve (11), and the pressure is reduced from 9... The pressure dropped from 12 MPa to 7.5 MPa. The pressure was 9 MPa, and the temperature dropped slightly. After throttling, the working fluid entered the carbon dioxide expander (12), where the pressure further decreased to 7.5 MPa during the expansion process. 8.5 MPa, temperature reduced to 80 200 The fourth supercritical carbon dioxide working fluid is obtained. This fourth supercritical carbon dioxide working fluid remains in a single-phase supercritical state and is transported to the inlet of the solar collector (13) to absorb solar radiation heat again, forming a continuous closed loop. Through a cycle path of compression heating – air cooler heat release – internal heat exchange – throttling – expansion – solar reheat absorption, a complete supercritical carbon dioxide high-temperature heat pump cycle is formed. This cycle can continuously output 450... 650 The high-quality heat flow is delivered to the air cooler (8) and the high-temperature heat exchanger (2), thereby providing stable heat energy for the steam circulation module and ensuring long-term stable operation of the solid oxide electrolysis cell in the range of 700 to 900°C.

[0049] In some embodiments, the process of depressurizing and expanding the third supercritical carbon dioxide working fluid through the low-pressure side regulating submodule to obtain the fourth supercritical carbon dioxide working fluid includes: performing internal heat exchange on the third supercritical carbon dioxide working fluid through an internal heat exchanger to obtain a preheated supercritical carbon dioxide working fluid; performing throttling and depressurizing treatment on the preheated supercritical carbon dioxide working fluid through a throttling valve to obtain a depressurized supercritical carbon dioxide working fluid; and performing expansion and work treatment on the depressurized supercritical carbon dioxide working fluid through a carbon dioxide expander to obtain the fourth supercritical carbon dioxide working fluid, wherein the low-pressure side regulating submodule includes the internal heat exchanger, the throttling valve, and the carbon dioxide expander.

[0050] In some embodiments, the third supercritical carbon dioxide working fluid is subjected to internal heat exchange treatment through an internal heat exchanger to obtain a preheated supercritical carbon dioxide working fluid. Specifically, the third supercritical carbon dioxide working fluid is the working fluid after heat release by the gas cooler (8), and its temperature range is 250°C. 400 The pressure range is 9. The pressure is 12 MPa, and it is in a stable supercritical single-phase state. The third supercritical carbon dioxide working fluid flows out from the hot end outlet of the gas cooler (8) and enters the hot end inlet of the internal heat exchanger (9). In the internal heat exchanger (9), it undergoes indirect convection heat exchange with the lower-temperature supercritical carbon dioxide working fluid from the outlet of the solar collector (13). The internal heat exchanger (9) is preferably a high-efficiency plate or microchannel heat exchanger with a heat exchange efficiency of not less than 75%. During the heat exchange process, the third supercritical carbon dioxide working fluid releases sensible heat to the low-temperature working fluid, and its temperature drops from 250°C to 12 MPa. 400 Reduced to 200 320 The pressure remained basically at 9 Within the 12MPa range, no significant changes occur, and the supercritical state is maintained. The working fluid after internal heat exchange flows out from the hot end outlet of the internal heat exchanger (9) to obtain pre-cooled supercritical carbon dioxide working fluid, which provides suitable inlet parameters for subsequent depressurization and expansion treatment.

[0051] In some embodiments, the preheated supercritical carbon dioxide working fluid is throttled and depressurized using a throttling valve to obtain a depressurized supercritical carbon dioxide working fluid. Specifically, the preheated supercritical carbon dioxide working fluid enters the inlet of the throttling valve (11) from the hot end outlet of the internal heat exchanger (9). The throttling valve (11) is preferably a high-pressure needle valve or an electric regulating valve, used to precisely control the flow rate and pressure. During the throttling process, the working fluid undergoes approximately isenthalpic throttling expansion, and its pressure is reduced from 9... 12MPa reduced to 8 10 MPa, the temperature drops accordingly to 180°C 280 Because the initial state is much higher than the critical point (critical temperature 31.1°C). (Critical pressure 7.38 MPa) After throttling, the working fluid remains in a supercritical single-phase state and does not undergo gas-liquid two-phase separation. The working fluid after throttling and depressurization flows out from the outlet of the throttling valve (11) to obtain depressurized supercritical carbon dioxide working fluid, creating conditions for it to enter the expander for further work and cooling.

[0052] In some embodiments, the supercritical carbon dioxide working fluid undergoes expansion and work-generating treatment via a carbon dioxide expander to obtain the fourth supercritical carbon dioxide working fluid. The low-pressure side regulating submodule includes the internal heat exchanger, the throttling valve, and the carbon dioxide expander. Specifically, the supercritical carbon dioxide working fluid enters the inlet of the carbon dioxide expander (12) from the outlet of the throttling valve (11). The carbon dioxide expander (12) is preferably a radial or axial flow turbine structure with an isentropic efficiency of 70%. 85%. During the expansion process, the working fluid expands in volume and outputs mechanical work, which can be used to drive a generator or partially compensate for the power consumption of the compressor. Its pressure is 8... The pressure was further reduced from 10 MPa to 7.5. 8.5 MPa, temperature reduced to 80 200 Because the expansion termination pressure is still higher than the critical pressure of 7.38 MPa, and the temperature is much higher than the critical temperature of 31.1 MPa. Therefore, the expanded working fluid remains in a supercritical single-phase state and does not condense. The expanded working fluid flows out from the outlet of the carbon dioxide expander (12) to obtain the fourth supercritical carbon dioxide working fluid. The fourth supercritical carbon dioxide working fluid then enters the inlet of the solar collector (13) and absorbs solar thermal energy under the action of solar radiation, with the temperature rising from 80°C. 200 Increased to 250 400 The pressure is maintained at 7.5. Within the range of 8.5 MPa. The heated working fluid then enters the cold end of the internal heat exchanger (9) to exchange heat with the high-temperature working fluid from the air cooler (8) and then enters the carbon dioxide compressor (10) to complete the compression and heating process, forming a closed loop.

[0053] In some embodiments, through the synergistic effect of the low-pressure side regulation submodule, the following are achieved: heat recovery and temperature optimization matching of the working fluid after heat release from the gas cooler; pressure gradient regulation through throttling and expansion; partial energy recovery through expansion work; ensuring that the working fluid entering the solar collector is in a suitable low-temperature, high-density range; and ensuring that the entire carbon dioxide cycle is always maintained at 7.5. It operates within the supercritical range of 12 MPa. This constitutes a complete supercritical carbon dioxide high-temperature heat pump cycle path: compression and heating. Air cooler heat dissipation Internal heat exchange Throttling and reducing blood pressure Expansion and work Solar reheating Internal heat exchange heating Further compression. This loop can continuously output 450. 650 The high-quality heat flow to the air cooler (8) and the high-temperature heat exchanger (2) provides stable heat energy to the steam circulation module, thereby ensuring that the solid oxide electrolysis cell (1) operates at 700°C. 900 It operates stably within the specified range for an extended period.

[0054] In some embodiments, the steam circulation module further includes: a steam condenser, a gas-liquid separator, and a hydrogen storage device; the steam condenser condenses the electrolytic gas output from the solid oxide electrolysis cell to obtain a condensed mixed fluid; the gas-liquid separator separates the condensed mixed fluid to obtain liquid water and hydrogen; the water collection tank and the hydrogen storage device respectively recover and store the liquid water and the hydrogen to obtain circulating water and target hydrogen.

[0055] In some embodiments, the electrolytic gas output from the solid oxide electrolytic cell is condensed by the steam condenser to obtain a condensed mixed fluid. Specifically, the electrolytic gas is a mixture of hydrogen gas discharged from the outlet of the solid oxide electrolytic cell (1) and unreacted water vapor, with a temperature range of 650°C. 900 The pressure range is 0.1. 0.5MPa. The electrolytic gas first enters the hot end of the high-temperature heat exchanger (2) for waste heat recovery, and the temperature is reduced to 200. 350 Then, it enters the hot end inlet of the steam condenser (3) from the hot end outlet of the high-temperature heat exchanger (2). The steam condenser (3) is preferably a shell-and-tube or plate condenser heat exchanger, with cooling water or circulating cooling medium flowing through its cold end. The temperature range of the cooling medium is 15°C. 40 During the condensation process, water vapor in the electrolytic gas undergoes a phase change condensation on the inner wall of the condenser, releasing latent heat and transforming into liquid water; the overall temperature of the mixed gas increases from 200°C. 350 Reduced to 30 80 Within this temperature range, water vapor is essentially condensed, while hydrogen remains in a gaseous state. After condensation, a condensed mixed fluid is output from the hot end outlet of the water vapor condenser (3), the condensed mixed fluid comprising a two-phase mixture of liquid water and gaseous hydrogen.

[0056] In some embodiments, the condensed mixed fluid is subjected to gas-liquid separation treatment by the gas-liquid separator to obtain liquid water and hydrogen. Specifically, the condensed mixed fluid enters the inlet of the gas-liquid separator (4) from the hot end outlet of the water vapor condenser (3). The gas-liquid separator (4) is preferably a gravity settling separator, a cyclone separator, or a membrane separation device. When a gravity settling structure is used, the flow rate of the mixed fluid decreases after entering the separation chamber. Under the action of gravity, the liquid water settles to the bottom of the separator to form a liquid phase zone, and the gaseous hydrogen accumulates in the upper gas phase zone. When a cyclone separation structure is used, the mixed fluid enters tangentially to form a rotating flow field. Under the action of centrifugal force, the liquid water is thrown to the outer wall and sinks, and the gaseous hydrogen rises and is discharged from the central region. When a membrane separation device is used, the purity of hydrogen is improved by selective hydrogen permeation membrane. After separation, liquid water is output from the bottom outlet at a temperature of 30°C. 80 The pressure is close to atmospheric pressure; gaseous hydrogen is output from the top outlet, with a volume fraction preferably not less than 99%. This results in two independent fluids: liquid water and hydrogen, achieving physical separation of the electrolysis products.

[0057] In some embodiments, the liquid water and hydrogen are recovered and stored separately through the water collection tank and the hydrogen storage device to obtain circulating water and target hydrogen, respectively. Specifically, the liquid water flows out from the bottom outlet of the gas-liquid separator (4) and enters the water collection tank (6) through the return pipe. The water collection tank (6) is a corrosion-resistant sealed container with a volume determined according to the system scale. It is used to store the recovered water and maintain a stable water supply pressure in the water circulation system. The temperature of the liquid water entering the water collection tank is 30°C. 80 It can be further cooled to 20°C through natural cooling or auxiliary heat exchange. 40 This forms circulating water that can re-enter the water pump (7). The circulating water is pressurized to 0.2 by the water pump (7). After reaching 1.0 MPa, the hydrogen re-enters the cold end inlet of the gas cooler (8) to participate in the next round of steam heating and electrolysis, thus forming a closed-loop water circulation. The hydrogen is discharged from the top outlet of the gas-liquid separator (4) and then enters the hydrogen storage device (5). The hydrogen storage device (5) can be a high-pressure gas cylinder, a hydrogen storage tank, or a solid hydrogen storage unit. When using high-pressure storage, the hydrogen can be compressed to 10 MPa by a compressor. Store at 35 MPa; when using low-pressure buffered storage, it can be stored at 0.5 MPa. After temporary storage within a pressure range of 2 MPa, the hydrogen is exported for use. The hydrogen purity entering the storage device is preferably greater than 99%, and the water content is less than 500 ppm, meeting the standards for industrial or fuel cell use. This process yields circulating water and the target hydrogen, achieving closed-loop water resource recycling and stable output of high-purity hydrogen.

[0058] Through the above steps, a two-stage heating and high-temperature vaporization process of water is achieved, fully recovering the waste heat of electrolytic gas and synergistically coupling it with a supercritical carbon dioxide heat pump cycle to improve the overall thermal utilization rate of the system. At the same time, a stable output of high-quality thermal energy and energy cascade utilization are achieved through a supercritical carbon dioxide closed-loop high-temperature heat pump cycle, and a closed-loop water resource cycle and stable output of high-purity hydrogen are achieved through condensation and gas-liquid separation. This reduces system energy consumption, improves thermoelectric synergy efficiency, ensures long-term stable operation of the solid oxide electrolyzer in the high-temperature range, and can improve the hydrogen production efficiency of the solid oxide electrolyzer under supercritical carbon dioxide high-temperature heat pump cycle conditions.

[0059] Step S103: Hydrogen gas is obtained by electrochemically decomposing the target water vapor in the solid oxide electrolytic cell of the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide circulation module.

[0060] In some embodiments, the temperature of the target water vapor is 650°C. 850 The pressure is 0.2. A pressure of 1.0 MPa is introduced into the cathode side of the solid oxide electrolyzer (SOEC) through an insulated pipe. The supercritical carbon dioxide circulation module continuously supplies heat to the SOEC via an air cooler and a high-temperature heat exchanger, maintaining the operating temperature of the electrolyzer at 700°C. 900 Within the range, 750 is preferred. 850 Under the action of a DC power supply, the electrolytic cell is subjected to a single-cell voltage of 1.1. 1.5V, current density 0.3 1.5A / cm 2 Water vapor undergoes a reduction reaction at the cathode to produce hydrogen and oxygen ions. These oxygen ions migrate through the electrolyte to the anode to form oxygen. After electrolysis, a mixture of hydrogen and a small amount of unreacted water vapor is output from the cathode, while oxygen is output from the anode. The water vapor conversion rate is 60%. 90%. Through the continuous heating provided by the supercritical carbon dioxide circulation module, stable thermal support is achieved for the solid oxide electrolyzer, reducing the electrical power required for electrolysis and improving hydrogen production efficiency, thereby obtaining a continuous output of hydrogen.

[0061] Through the above steps, under the condition of continuous and stable heating from the supercritical carbon dioxide cycle module, the solid oxide electrolyzer is maintained in the high-temperature and high-efficiency operating range, reducing the external electrical work required for electrolysis, improving the water vapor conversion rate and current efficiency, achieving continuous and stable hydrogen output, and improving the overall energy utilization efficiency and hydrogen production efficiency of the system.

[0062] like Figure 3As shown, based on the above method embodiments, corresponding apparatus embodiments are provided; An embodiment of the present invention provides a schematic diagram of a hydrogen production system integrating a carbon dioxide heat pump, including: a preheating module 100, a heat exchange module 200, and a hydrogen production module 300; The preheating module 100 is used to pressurize the water stored in the water collection tank through the water pump in the steam circulation module to obtain pressurized water, and to perform heat exchange treatment on the pressurized water based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. The heat exchange module 200 is used to further heat the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. The hydrogen production module 300 is used to electrochemically decompose the target water vapor through the solid oxide electrolytic cell in the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide circulation module to obtain hydrogen.

[0063] It is understood that the above-described apparatus embodiments correspond to the method embodiments of the present invention, and can implement the hydrogen production method with an integrated carbon dioxide heat pump provided by any of the above-described method embodiments of the present invention. More detailed workflows and principles of this system can be found, but are not limited to, in the relevant descriptions of the above methods.

[0064] It should be noted that the device embodiments described above are merely illustrative, and some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can specifically be implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0065] Based on the above embodiments of the hydrogen production method using an integrated carbon dioxide heat pump, another embodiment of the present invention provides a terminal device, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the hydrogen production method using an integrated carbon dioxide heat pump according to any embodiment of the present invention.

[0066] For example, in this embodiment, the computer program can be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program in the terminal device.

[0067] The terminal device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0068] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0069] Based on the above-described method embodiments, another embodiment of the present invention provides a computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the hydrogen production method of the integrated carbon dioxide heat pump described in any of the above-described method embodiments of the present invention.

[0070] The modules / units integrated in the device / terminal equipment, if implemented as software functional units and sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0071] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A method for producing hydrogen using an integrated carbon dioxide heat pump, characterized in that, Suitable for hydrogen production systems, the hydrogen production system comprising: a steam cycle module, an electrolysis reaction module, and a supercritical carbon dioxide cycle module; The water stored in the water collection tank is pressurized by the water pump in the steam circulation module to obtain pressurized water. The pressurized water is then subjected to heat exchange treatment based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. The heated water is subjected to another heat exchange process through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. Hydrogen gas is obtained by electrochemically decomposing the target water vapor in the solid oxide electrolytic cell of the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide circulation module.

2. The hydrogen production method using an integrated carbon dioxide heat pump as described in claim 1, characterized in that, The process of using the target supercritical carbon dioxide working fluid obtained from the air cooler in the steam circulation module to perform heat exchange treatment on the pressurized water to obtain heated water includes: The target supercritical carbon dioxide working fluid is introduced into the hot end channel of the air cooler through the hot end inlet of the steam circulation module for flow treatment, so as to obtain the flowing supercritical carbon dioxide working fluid. The pressurized water is introduced into the cold end channel of the air cooler through the cold end inlet of the steam circulation module for flow treatment, thus obtaining flowing pressurized water. The first heat exchange wall of the air cooler performs countercurrent heat exchange between the flowing supercritical carbon dioxide working fluid and the flowing pressurized water, so as to raise the temperature of the flowing pressurized water by the heat energy released by the flowing supercritical carbon dioxide working fluid, thereby obtaining heated water.

3. The hydrogen production method using an integrated carbon dioxide heat pump as described in claim 1, characterized in that, The step of further heat-exchanging the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam includes: The heated water is introduced into the cold end channel of the high-temperature heat exchanger through the cold end inlet of the high-temperature heat exchanger in the steam circulation module for flow treatment, so as to obtain flowing heated water. Electrolytic gas output from the solid oxide electrolysis cell is introduced into the hot end channel of the high-temperature heat exchanger through the hot end inlet of the high-temperature heat exchanger in the steam circulation module for flow treatment, thereby obtaining flowing electrolytic gas. The second heat exchange wall of the high-temperature heat exchanger performs convective heat exchange on the flowing heated water and the flowing electrolytic gas, so as to vaporize the flowing heated water through the heat released by the flowing electrolytic gas to obtain the target water vapor.

4. The hydrogen production method using an integrated carbon dioxide heat pump as described in claim 1, characterized in that, The supercritical carbon dioxide cycle module includes: a carbon dioxide compressor, an air cooler, a solar collector, and a low-pressure side regulation submodule; The first supercritical carbon dioxide working fluid is obtained by absorbing heat and raising the temperature of the pre-charged supercritical carbon dioxide working fluid through the solar collector. The first supercritical carbon dioxide working fluid is compressed and heated by the carbon dioxide compressor to obtain the second supercritical carbon dioxide working fluid. The second supercritical carbon dioxide working fluid is subjected to heat exchange treatment by the air cooler to transfer the heat released by the second supercritical carbon dioxide working fluid to the water vapor circulation module, so as to obtain the third supercritical carbon dioxide working fluid. The third supercritical carbon dioxide working fluid is depressurized and expanded by the low-pressure side regulation submodule to obtain the fourth supercritical carbon dioxide working fluid. The fourth supercritical carbon dioxide working fluid is then transported to the solar collector for heat absorption again to form a closed loop, thus obtaining the target supercritical carbon dioxide working fluid for continuously providing heat energy to the water vapor circulation module.

5. The hydrogen production method using an integrated carbon dioxide heat pump as described in claim 4, characterized in that, The process of depressurizing and expanding the third supercritical carbon dioxide working fluid through the low-pressure side regulation submodule to obtain the fourth supercritical carbon dioxide working fluid includes: The third supercritical carbon dioxide working fluid is subjected to internal heat exchange treatment through an internal heat exchanger to obtain a preheated supercritical carbon dioxide working fluid. The preheated supercritical carbon dioxide working fluid is throttled and depressurized using a throttling valve to obtain a depressurized supercritical carbon dioxide working fluid. The supercritical carbon dioxide working fluid is expanded and subjected to work by a carbon dioxide expander to obtain the fourth supercritical carbon dioxide working fluid. The low-pressure side regulating submodule includes the internal heat exchanger, the throttling valve and the carbon dioxide expander.

6. The hydrogen production method using an integrated carbon dioxide heat pump as described in claim 1, characterized in that, The steam circulation module also includes: a steam condenser, a gas-liquid separator, and a hydrogen storage device; The electrolytic gas output from the solid oxide electrolytic cell is condensed by the steam condenser to obtain a condensed mixed fluid; The condensed mixed fluid is subjected to gas-liquid separation treatment by the gas-liquid separator to obtain liquid water and hydrogen. The liquid water and hydrogen are recovered and stored through the water collection tank and the hydrogen storage device to obtain circulating water and target hydrogen respectively.

7. A hydrogen production system integrating a carbon dioxide heat pump, characterized in that, The system includes: a preheating module, a heat exchange module, and a hydrogen production module; The preheating module is used to pressurize the water stored in the water collection tank through the water pump in the steam circulation module to obtain pressurized water. The pressurized water is then subjected to heat exchange treatment based on the target supercritical carbon dioxide working fluid obtained by the air cooler in the steam circulation module to obtain heated water. The target supercritical carbon dioxide working fluid is obtained by the supercritical carbon dioxide circulation module through heat pump circulation treatment of pre-charged supercritical carbon dioxide working fluid. The heat exchange module is used to further heat the heated water through the high-temperature heat exchanger in the steam circulation module to obtain the target steam. The hydrogen production module is used to electrochemically decompose the target water vapor through the solid oxide electrolysis cell in the electrolysis reaction module under the continuous heating condition of the supercritical carbon dioxide cycle module to obtain hydrogen.

8. A terminal device, characterized in that, The device includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein, when the processor executes the computer program, it implements the hydrogen production method of the integrated carbon dioxide heat pump as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, include: A stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the hydrogen production method of the integrated carbon dioxide heat pump as described in any one of claims 1-6.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by the communication device, the hydrogen production method of the integrated carbon dioxide heat pump as described in any one of claims 1 to 6 is implemented.

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