Gas-liquid separation and heat energy recovery device of electrolytic hydrogen production system

Abstract

The invention relates to the technical field of hydrogen production through water electrolysis, in particular to a gas-liquid separation and heat energy recovery device of an electrolytic hydrogen production system, which comprises at least one electrochemical hydrogen pump, each electrochemical hydrogen pump is provided with a mixed gas inlet, a mixed gas outlet and a hydrogen outlet, the number of the electrochemical hydrogen pumps is multiple, and in every two adjacent electrochemical hydrogen pumps, the mixed gas inlet is communicated with the mixed gas outlet; the mixed gas outlet of the previous electrochemical hydrogen pump is communicated with the mixed gas inlet of the next electrochemical hydrogen pump; the device further comprises a steam ejector, the steam ejector is provided with an ejection fluid inlet, and the mixed gas outlet of the last electrochemical hydrogen pump is communicated with the ejection fluid inlet in the flowing direction of the mixed gas. According to the gas-liquid separation and heat energy recovery device, the electrochemical hydrogen pump and the steam ejector are combined, heat energy generated by the electrochemical hydrogen pump is efficiently utilized, efficient reutilization of steam heat energy is achieved, and the energy utilization rate is increased.

Description

Technical Field

[0001] This application relates to the field of water electrolysis for hydrogen production technology, specifically to a gas-liquid separation and heat recovery device for an electrolysis hydrogen production system. Background Technology

[0002] Related technologies for hydrogen production systems use electrolytic hydrogen pumps to separate and purify hydrogen. However, the Joule heat generated by the electrochemical hydrogen pump can only be carried away by hydrogen or a cooling medium, resulting in energy waste and the inability to convert it into usable heat. Furthermore, the output product of the electrochemical hydrogen pump is only high-pressure, high-purity hydrogen, and the water vapor in the mixed gas cannot be efficiently utilized, resulting in a waste of thermal energy. Summary of the Invention

[0003] The purpose of this application is to provide a gas-liquid separation and heat recovery device for an electrolytic hydrogen production system, achieving gas-liquid separation and heat recovery. The specific solution is as follows:

[0004] A gas-liquid separation and heat recovery device for an electrolytic hydrogen production system includes at least one electrochemical hydrogen pump, which has a mixed gas inlet, a mixed gas outlet and a hydrogen outlet. The number of electrochemical hydrogen pumps is multiple, and in two adjacent electrochemical hydrogen pumps, the mixed gas outlet of the preceding electrochemical hydrogen pump and the mixed gas inlet of the following electrochemical hydrogen pump are connected.

[0005] The gas-liquid separation and heat recovery device further includes a steam ejector with an ejector fluid inlet. In the direction of gas flow, the gas outlet of the last electrochemical hydrogen pump is connected to the ejector fluid inlet.

[0006] Optionally, the electrochemical hydrogen pump includes at least one hydrogen pump unit, and the number of hydrogen pump units is multiple, with the multiple hydrogen pump units stacked in a stacked manner. In the direction of hydrogen flow, the cathode side of the preceding hydrogen pump unit and the anode side of the following hydrogen pump unit are interconnected. The hydrogen pump unit is configured to move and pressurize the hydrogen in the mixed gas on the anode side towards the cathode side.

[0007] The mixed gas inlet, the mixed gas outlet, and the anode side of the first hydrogen pump unit are connected, and the hydrogen outlet and the cathode side of the last hydrogen pump unit are connected.

[0008] Optionally, the electrochemical hydrogen pump further includes an isolation assembly disposed between two adjacent hydrogen pump units. The isolation assembly includes a bipolar plate insulating sheet and bipolar plates disposed on both sides of the bipolar plate insulating sheet. The bipolar plate insulating sheet and the bipolar plates are respectively provided with through holes, which are configured to connect the cathode side of the preceding hydrogen pump unit and the anode side of the following hydrogen pump unit in the direction of hydrogen flow.

[0009] Optionally, the bipolar plate is provided with a pressure detection channel, which is connected to the through hole, and the axis of the pressure detection channel and the axis of the through hole have an angle.

[0010] Optionally, the material of the bipolar plate insulating sheet is at least one of polytetrafluoroethylene, polyetheretherketone, polyethylene, and polypropylene.

[0011] Optionally, the gas-liquid separation and heat recovery device further includes a control circuit, which is electrically connected to the hydrogen pump unit in a one-to-one correspondence, and the control circuit is configured to adjust the operating voltage of the corresponding hydrogen pump unit.

[0012] Optionally, the theoretical decomposition voltage of water electrolysis at the current temperature in the hydrogen pump unit is defined as U1, and the operating voltage of the hydrogen pump unit is U2, where U2 < U1.

[0013] Optionally, the electrochemical hydrogen pump further includes an anode end plate and a cathode end plate disposed opposite to each other, and an insulating screw, the insulating screw being fixedly connected to the anode end plate and the cathode end plate, the hydrogen pump unit being clamped between the anode end plate and the cathode end plate, the anode end plate being located on the anode side of the first hydrogen pump unit in the direction of hydrogen flow, and the cathode end plate being located on the cathode side of the last hydrogen pump unit in the direction of hydrogen flow;

[0014] The anode plate is provided with a first flow channel on the end wall facing the hydrogen pump unit. One end of the first flow channel forms the mixed gas outlet, and the other end of the first flow channel forms the mixed gas inlet.

[0015] The cathode end plate is provided with a second flow channel facing the end wall of the hydrogen pump unit, and one end of the second flow channel forms the hydrogen outlet.

[0016] This application also provides an electrolytic hydrogen production system, including the aforementioned gas-liquid separation and heat recovery device.

[0017] The electrolytic hydrogen production system of this application includes the aforementioned gas-liquid separation and heat recovery device, and therefore has the same technical effect as the aforementioned gas-liquid separation and heat recovery device, which will not be repeated here.

[0018] Optionally, the steam ejector has a fluid outlet that is connected to the steam inlet of other devices in the electrolysis hydrogen production system.

[0019] The technical effects of this application are as follows:

[0020] This application's gas-liquid separation and heat recovery device includes at least one electrochemical hydrogen pump and a steam ejector. During operation, a mixed gas (containing superheated steam and hydrogen with other impurities) first enters the electrochemical hydrogen pump. Through electrochemical pressurization and purification, the hydrogen pressure is increased to the required value, while impurities and moisture in the hydrogen are reduced. The hydrogen outlet of the electrochemical hydrogen pump outputs high-pressure, high-purity hydrogen. When there are multiple electrochemical hydrogen pumps, the remaining mixed gas output from the outlet of the previous electrochemical hydrogen pump enters the next electrochemical hydrogen pump, and some of the hydrogen is further purified through electrochemical pressurization. The gas mixture is then discharged from the hydrogen outlet, and the remaining mixed gas enters the next electrochemical hydrogen pump, and so on, until the mixed gas outlet of the last electrochemical hydrogen pump is high-purity superheated steam. During this process, a portion of the heat energy generated by each electrochemical hydrogen pump will be absorbed by the steam, realizing the recovery and utilization of waste heat. The superheated steam output from the mixed gas outlet of the last electrochemical hydrogen pump is fed into a steam ejector. The steam ejector can increase the steam grade by pressurizing it. The steam output from the steam ejector can be used for preheating other devices in the electrolytic hydrogen production system or for external heat energy supply.

[0021] Therefore, the gas-liquid separation and heat recovery device of this application can efficiently utilize the heat energy generated by the electrochemical hydrogen pump and realize the efficient reuse of steam heat energy, thereby improving energy utilization. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a specific embodiment of the gas-liquid separation and heat recovery device for the electrolytic hydrogen production system provided in this application.

[0023] Figure 2 for Figure 1 A simplified structural diagram of the gas-liquid separation and heat recovery unit in an electrolytic hydrogen production system;

[0024] Figure 3 for Figure 1 A schematic diagram of the electrochemical hydrogen pump in the gas-liquid separation and heat recovery device of an electrolytic hydrogen production system;

[0025] Figure 4 for Figure 3 Component diagram of an electrochemical hydrogen pump;

[0026] Figure 5 for Figure 1 A simplified structural diagram of the control circuit in the gas-liquid separation and heat recovery device of an electrolytic hydrogen production system;

[0027] Explanation of reference numerals in the attached figures:

[0028] Electrochemical hydrogen pump 1; Mixed gas inlet 11; Mixed gas outlet 12; Hydrogen outlet 13; Hydrogen pump unit 14; Anode sealing gasket 141; Anode support 142; Membrane electrode assembly 143; Cathode support 144; Cathode sealing gasket 145; Isolation assembly 15; Bipolar plate insulating sheet 151; Bipolar plate 152; Through hole 153; Anode end plate 16; Cathode end plate 17; Second flow channel 171; Insulating screw 18;

[0029] Steam ejector 2; ejector fluid inlet 21; fluid outlet 22;

[0030] Control circuit 3. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0033] It should be understood that the phrase "some embodiments" throughout the specification means that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this application. Therefore, "some embodiments" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0034] In this description, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" 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. Those skilled in the art will understand the specific meaning of these terms in this document based on the specific circumstances.

[0035] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a specific embodiment of the gas-liquid separation and heat recovery device for the electrolytic hydrogen production system provided in this application.

[0036] This application provides a gas-liquid separation and heat recovery device for an electrolytic hydrogen production system, including at least one electrochemical hydrogen pump 1. The electrochemical hydrogen pump 1 has a mixed gas inlet 11, a mixed gas outlet 12 and a hydrogen outlet 13. There are multiple electrochemical hydrogen pumps 1. In two adjacent electrochemical hydrogen pumps 1, the mixed gas outlet 12 of the previous electrochemical hydrogen pump 1 and the mixed gas inlet 11 of the next electrochemical hydrogen pump 1 are connected.

[0037] The gas-liquid separation and heat recovery device also includes a steam ejector 2, which has an ejector fluid inlet 21. In the direction of flow of the mixed gas, the mixed gas outlet 12 of the last electrochemical hydrogen pump 1 is connected to the ejector fluid inlet 21.

[0038] The gas-liquid separation and heat recovery device of this application includes at least one electrochemical hydrogen pump 1 and a steam ejector 2. During operation, a mixed gas (containing superheated steam and other impurities) first enters the electrochemical hydrogen pump 1. Through electrochemical pressurization and purification, the hydrogen pressure is increased to the required value, while impurities and moisture in the hydrogen are reduced. The hydrogen outlet 13 of the electrochemical hydrogen pump 1 outputs high-pressure, high-purity hydrogen, for example, in some embodiments, the output hydrogen pressure is 3 MPa. When there are multiple electrochemical hydrogen pumps 1, the remaining mixed gas output from the mixed gas outlet 12 of the previous electrochemical hydrogen pump 1 enters the next electrochemical hydrogen pump 1, and some hydrogen is purified by electrochemical pressurization and purification before exiting the hydrogen outlet. The gas mixture is discharged from outlet 13, and the remaining mixed gas enters the next electrochemical hydrogen pump 1, and so on, until the mixed gas outlet 12 of the last electrochemical hydrogen pump 1 is high-purity superheated steam. During this process, part of the heat energy generated by each electrochemical hydrogen pump 1 will be absorbed by the steam, realizing the recovery and utilization of waste heat. The superheated steam output from the mixed gas outlet 12 of the last electrochemical hydrogen pump 1 is fed into the steam ejector 2. The steam ejector 2 can increase the steam quality by pressurizing it. For example, in some embodiments, the steam ejector 2 outputs steam with a pressure increased to 3 bar, which can be used for preheating other devices in the electrolytic hydrogen production system or for external heat energy supply, thus completing the recovery and utilization of heat energy and steam.

[0039] Therefore, the gas-liquid separation and heat recovery device of this application can efficiently utilize the heat energy generated by the electrochemical hydrogen pump and realize the efficient reuse of steam heat energy, thereby effectively improving the energy utilization rate.

[0040] Please refer to Figure 2 , Figure 2 for Figure 1A simplified structural diagram of the gas-liquid separation and heat recovery device in an electrolytic hydrogen production system.

[0041] In this embodiment of the application, the electrochemical hydrogen pump 1 includes at least one hydrogen pump unit 14, and the number of hydrogen pump units 14 is multiple. The multiple hydrogen pump units 14 are stacked and arranged in the direction of hydrogen flow. The cathode side of the previous hydrogen pump unit 14 and the anode side of the next hydrogen pump unit 14 are interconnected. The hydrogen pump unit 14 is configured to move the hydrogen in the mixed gas supplied to the anode side to the cathode side and pressurize it.

[0042] The mixed gas inlet 11, the mixed gas outlet 12, and the anode side of the first hydrogen pump unit 14 are connected, and the hydrogen outlet 13 and the cathode side of the last hydrogen pump unit 14 are connected.

[0043] As set up above, during operation, the mixed gas is introduced from the anode side of the first hydrogen pump unit 14, where the hydrogen moves to the cathode side and is pressurized, initially removing superheated water vapor and other impurities from the mixed gas. When there are multiple hydrogen pump units 14, the initially purified hydrogen from the cathode side of the previous hydrogen pump unit 14 is directly introduced to the anode side of the next hydrogen pump unit 14 to enter the second stage of pressurization and purification. The next hydrogen pump unit 14 can further remove the remaining impurities, and so on, until the cathode side of the last hydrogen pump unit 14 outputs high-purity hydrogen to meet the subsequent demand for high-purity hydrogen.

[0044] The mixed gas outlet 12 is connected to the anode side of the first hydrogen pump unit 14, so that the remaining mixed gas after absorbing the heat energy generated by the electrochemical hydrogen pump 1 can be discharged in time.

[0045] Please refer to Figure 3 and Figure 4 , Figure 3 for Figure 1 A schematic diagram of the electrochemical hydrogen pump in the gas-liquid separation and heat recovery device of an electrolytic hydrogen production system; Figure 4 for Figure 3 A breakdown diagram of an electrochemical hydrogen pump.

[0046] In this embodiment of the application, the electrochemical hydrogen pump 1 further includes an isolation component 15, which is disposed between two adjacent hydrogen pump units 14. The isolation component 15 includes a bipolar plate insulating sheet 151 and bipolar plates 152 disposed on both sides of the bipolar plate insulating sheet 151. The bipolar plate insulating sheet 151 and the bipolar plates 152 are respectively provided with through holes 153. The through holes 153 are configured to connect the cathode side of the previous hydrogen pump unit 14 and the anode side of the next hydrogen pump unit 14.

[0047] The bipolar plate insulating sheet 151 can be made of insulating materials such as ceramics or plastics to block the current conduction between adjacent hydrogen pump units 14 and reduce the possibility of short circuit faults. The bipolar plate 152 can be made of materials such as metal or graphite. The bipolar plate 152 has both structural support and conductive functions. The bipolar plate 152 can conduct current as a cathode or anode. The bipolar plate insulating sheet 151 and the bipolar plate 152 are respectively provided with through holes 153. The through holes 153 are configured to connect the cathode side of the previous hydrogen pump unit 14 and the anode side of the next hydrogen pump unit 14, so that the hydrogen gas initially purified by the previous hydrogen pump unit 14 can be directly introduced into the next hydrogen pump unit 14, reducing the resistance in the hydrogen gas transportation process.

[0048] In this embodiment, the bipolar plate 152 is provided with a pressure detection channel, which is connected to the through hole 153. The axis of the pressure detection channel and the axis of the through hole 153 have an angle.

[0049] As configured above, the pressure detection channel allows a pressure sensor or pressure gauge to measure the internal hydrogen pressure. Based on the detection results, the operating voltage of the downstream hydrogen pump unit 14 can be adjusted so that the final output hydrogen pressure of the electrochemical hydrogen pump 1 meets the requirements. In some embodiments, the axis of the pressure detection channel and the axis of the through hole 153 are perpendicular to each other.

[0050] In this embodiment, the bipolar plate insulating sheet 151 is made of at least one of high-molecular heat-resistant plastics such as polytetrafluoroethylene, polyetheretherketone, polyethylene, and polypropylene.

[0051] Thus, the bipolar plate insulation sheet 151 has good heat resistance, reducing the possibility of deformation or aging of the bipolar plate insulation sheet 151 due to high temperature, improving the structural stability of the bipolar plate insulation sheet 151, extending the service life of the bipolar plate insulation sheet 151, enabling the bipolar plate insulation sheet 151 to stably perform its insulation function, and effectively reducing the risk of short circuit.

[0052] Please refer to Figure 5 , Figure 5 for Figure 1 A simplified diagram of the control circuit in the gas-liquid separation and heat recovery device of an electrolytic hydrogen production system.

[0053] In this embodiment of the application, the gas-liquid separation and heat recovery device further includes a control circuit 3, which is electrically connected to the hydrogen pump unit 14 in a one-to-one correspondence. The control circuit 3 is configured to adjust the voltage of the corresponding hydrogen pump unit 14.

[0054] As set up above, the hydrogen pump unit 14 operates in a separate power supply mode, and the control circuit 3 independently adjusts the voltage of the corresponding hydrogen pump unit 14 so that the operating voltage of each hydrogen pump unit 14 is within the required range.

[0055] Define the theoretical decomposition voltage of water electrolysis in hydrogen pump unit 14 at the current temperature as U1, and the operating voltage of hydrogen pump unit 14 as U2, where U2 < U1.

[0056] In this way, the operating voltage of each hydrogen pump unit 14 is kept below the theoretical decomposition voltage of water at the current temperature, thereby avoiding the electrolysis reaction and only realizing the migration and pressurization of hydrogen.

[0057] Under pressurized conditions, the mixed gas is introduced into the anode side of the hydrogen pump unit 14. At this time, each hydrogen pump unit 14 is supplied with an external current, and the operating voltage of the hydrogen pump unit 14 is kept below the theoretical decomposition voltage of water at the current temperature.

[0058] On the anode side, hydrogen gas reacts, with each hydrogen molecule losing 2 electrons and producing 2 protons. The half-reaction is as follows:

[0059]

[0060] On the cathode side, a reaction occurs where every two protons combine with two electrons to produce one hydrogen molecule. The half-reaction is as follows:

[0061]

[0062] The voltage during the pressurization process is determined by the Nernst equation, and the voltage is as follows:

[0063] in:

[0064] R—ideal gas constant (8.314 J / mol / K);

[0065] T – Temperature (K);

[0066] F — Faraday constant (96485 C / mol);

[0067] I——current (A);

[0068] R—Diaphragm internal resistance (Ω);

[0069] P1—Anode-side pressure;

[0070] P2—Cathode-side pressure.

[0071] Please continue to refer to this. Figure 4In this embodiment of the application, the electrochemical hydrogen pump 1 further includes an anode end plate 16 and a cathode end plate 17 disposed opposite to each other, and an insulating screw 18. The insulating screw 18 is fixedly connected to the anode end plate 16 and the cathode end plate 17. The hydrogen pump unit 14 is clamped between the anode end plate 16 and the cathode end plate 17. The anode end plate 16 is close to the anode side of the first hydrogen pump unit 14 in the direction of hydrogen flow, and the cathode end plate 17 is close to the cathode side of the last hydrogen pump unit 14 in the direction of hydrogen flow.

[0072] The end wall of the anode plate 16 facing the hydrogen pump unit 14 is provided with a first flow channel. One end of the first flow channel forms a mixed gas outlet 12, and the other end of the first flow channel forms a mixed gas inlet 11.

[0073] The end wall of the cathode plate 17 facing the hydrogen pump unit 14 is provided with a second flow channel 171, and one end of the second flow channel 171 forms a hydrogen outlet 13.

[0074] As configured above, the anode end plate 16 and the cathode end plate 17 are fixedly connected by an insulating screw 18, making the electrochemical hydrogen pump 1 a whole. The anode end plate 16 and the cathode end plate 17 can provide a constraint force in the stacking direction for the hydrogen pump unit 14, so that the hydrogen pump unit 14 maintains the stacked state under the action of the constraint force, improving the sealing reliability. The end wall of the anode end plate 16 facing the hydrogen pump unit 14 is provided with a first flow channel. One end of the first flow channel forms a mixed gas outlet 12, and the other end of the first flow channel forms a mixed gas inlet 11. The mixed gas enters the hydrogen pump unit 14 through the mixed gas inlet 11. After the first flow channel, the mixed gas can be evenly distributed to the anode side reaction area of ​​the first hydrogen pump unit 14, improving the uniformity of the mixed gas distribution and the efficiency of the electrochemical reaction. The remaining mixed gas that does not participate in the reaction can be directly and quickly discharged through the mixed gas outlet 12. The cathode end plate 17 is provided with a second flow channel 171 facing the end wall of the hydrogen pump unit 14. One end of the second flow channel 171 forms a hydrogen outlet 13. The high-pressure and high-purity hydrogen gas on the cathode side of the last hydrogen pump unit 14 can flow through the second flow channel 171 and be discharged from the hydrogen outlet 13, realizing the collection and stable output of high-pressure and high-purity hydrogen gas.

[0075] The first flow channel and the second flow channel 171 can be serpentine or bifurcated.

[0076] The edges of the anode plate 16 and the cathode plate 17 are provided with corresponding connection holes for the insulating screw 18 to pass through.

[0077] Please continue to refer to this. Figure 4In this embodiment, the hydrogen pump unit 14 includes a stacked anode sealing gasket 141, an anode support 142, a membrane electrode assembly 143, a cathode support 144, and a cathode sealing gasket 145. The anode support 142 and cathode support 144 reduce severe deformation and strain rupture of the membrane electrode assembly 143 under the influence of the bilateral hydrogen pressure difference, and also provide electrical conductivity. The structure of the anode support 142 and cathode support 144 can be one or more of the following porous metal structures: metal mesh, metal felt, porous metal sheet, or foam metal.

[0078] The materials of the anode plate 16, anode support 142, cathode support 144, bipolar plate 152, and cathode plate 17 can be one or more of the following: titanium, nickel, iron, molybdenum, chromium, gold, silver, graphite, etc.

[0079] The membrane electrode assembly 143 is a proton exchange membrane coated with catalyst slurry on both sides. The proton exchange membrane material can be one of the proton ion conductors such as perfluorosulfonic acid and its derivatives, polybenzimidazole and its derivatives, polyether ether ketone and its derivatives, proton conductor ceramics and their derivatives, etc. The cathode catalyst can be one or two of the catalysts such as platinum on carbon, palladium on carbon, and platinum, etc., and the anode catalyst can be one or more of the catalysts such as iridium oxide and platinum.

[0080] One embodiment of the gas-liquid separation and heat recovery device of this application includes the following steps:

[0081] S1. Device Assembly: Assemble the anode end plate 16 (made of titanium, with a serpentine first flow channel), anode sealing gasket 141, anode support 142 (made of nickel metal felt), and membrane electrode assembly 143 (using an m / p-PBI copolymer proton exchange membrane, doped with phosphoric acid (PA), with a polymer content of 16.8%). The following components are stacked in sequence: wt%, PA / PBI molar ratio of 10.8), cathode support 144 (made of nickel metal felt), cathode sealing gasket 145, and isolation assembly 15 (including bipolar plate 152 and bipolar plate insulating sheet 151, the bipolar plate 152 is made of titanium, and the bipolar plate insulating sheet 151 is made of polyetheretherketone). The structure of hydrogen pump unit 14 is repeated five times to form a five-stage electrochemical hydrogen pump 1. Two adjacent hydrogen pump units 14 are separated by isolation assembly 15. Finally, the cathode end plate 17 (made of titanium, with a serpentine second flow channel 171) is used to seal the top and is fastened with insulating screw 18 to form a complete electrochemical hydrogen pump 1. The mixed gas outlet 12 of the first electrochemical hydrogen pump 1 and the mixed gas inlet 11 of the second electrochemical hydrogen pump 1 are connected. The mixed gas outlet 12 of the last electrochemical hydrogen pump 1 is connected to the ejector fluid inlet 21 of the steam ejector 2.

[0082] S2. Inlet Pretreatment: The humid hydrogen gas from the outlet of the high-temperature electrolyzer is passed into the gas-liquid separation and heat recovery device, and the gas temperature is controlled at 180°C and the relative humidity is kept constant at 1.6%.

[0083] S3. Multi-stage electrochemical hydrogen pump treatment: The humid hydrogen gas from step S2 is introduced, and the electrochemical hydrogen pump 1 is started. Each stage of the hydrogen pump is controlled to operate at a current density of 0.2 A / cm². The hydrogen gas at the anode is oxidized into protons, which migrate through the membrane electrode assembly 143 to the cathode, where they combine with electrons to regenerate hydrogen gas. The unreacted mixed gas enters the subsequent hydrogen pump unit 14 step by step to continue the reaction and purification until the gas output from the mixed gas outlet 12 of the last electrochemical hydrogen pump 1 is mainly superheated steam, and the final output hydrogen gas pressure is 3 MPa.

[0084] S4. Heat recovery and steam pressurization: The Joule heat generated during the operation of the electrochemical hydrogen pump 1 is used to heat the residual water vapor to form superheated steam; this superheated steam is introduced into the steam ejector 2, mixed with the working steam and pressurized, and the output pressure is increased to 3 bar for steam preheating in the electrolytic hydrogen production system or external heat energy supply.

[0085] S5. Performance monitoring and control: By independently monitoring and adjusting the voltage of each hydrogen pump unit 14, the working voltage of each hydrogen pump unit 14 is kept below the theoretical decomposition voltage of water at the current temperature, thus avoiding water electrolysis; real-time monitoring of hydrogen purity, steam temperature and system pressure difference is used to achieve stable operation.

[0086] This application also includes an electrolytic hydrogen production system, comprising the aforementioned gas-liquid separation and heat recovery device.

[0087] The electrolytic hydrogen production system of this application includes the aforementioned gas-liquid separation and heat recovery device, and therefore has the same technical effects as the aforementioned gas-liquid separation and heat recovery device, which will not be repeated here.

[0088] In this embodiment, the steam ejector 2 has a fluid outlet 22, which is connected to the steam inlet of other devices in the electrolysis hydrogen production system.

[0089] As set up above, the steam output from steam ejector 2 can be used to preheat other devices in the electrolytic hydrogen production system, complete the recovery and utilization of heat energy and steam, improve energy utilization efficiency, reduce the demand for external steam, and reduce operating costs.

[0090] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A gas-liquid separation and heat recovery device for an electrolytic hydrogen production system, characterized in that, Includes at least one electrochemical hydrogen pump (1), the electrochemical hydrogen pump (1) having a mixed gas inlet (11), a mixed gas outlet (12) and a hydrogen outlet (13), the number of electrochemical hydrogen pumps (1) is multiple, and in two adjacent electrochemical hydrogen pumps (1), the mixed gas outlet (12) of the previous electrochemical hydrogen pump (1) and the mixed gas inlet (11) of the next electrochemical hydrogen pump (1) are connected; The gas-liquid separation and heat recovery device also includes a steam ejector (2), which has an ejector fluid inlet (21). In the direction of flow of the mixed gas, the mixed gas outlet (12) of the last electrochemical hydrogen pump (1) is connected to the ejector fluid inlet (21).

2. The gas-liquid separation and heat recovery device according to claim 1, characterized in that, The electrochemical hydrogen pump (1) includes at least one hydrogen pump unit (14), and there are multiple hydrogen pump units (14) stacked together. In the direction of hydrogen flow, the cathode side of the previous hydrogen pump unit (14) and the anode side of the next hydrogen pump unit (14) are interconnected. The hydrogen pump unit (14) is configured to move and pressurize the hydrogen in the mixed gas on the anode side to the cathode side. The mixed gas inlet (11), the mixed gas outlet (12), and the anode side of the first hydrogen pump unit (14) are connected, and the hydrogen outlet (13) and the cathode side of the last hydrogen pump unit (14) are connected.

3. The gas-liquid separation and heat recovery device according to claim 2, characterized in that, The electrochemical hydrogen pump (1) further includes an isolation component (15) disposed between two adjacent hydrogen pump units (14). The isolation component (15) includes a bipolar plate insulating sheet (151) and bipolar plates (152) disposed on both sides of the bipolar plate insulating sheet (151). The bipolar plate insulating sheet (151) and the bipolar plates (152) are respectively provided with through holes (153). The through holes (153) are configured to connect the cathode side of the previous hydrogen pump unit (14) and the anode side of the next hydrogen pump unit (14) in the direction of hydrogen flow.

4. The gas-liquid separation and heat recovery device according to claim 3, characterized in that, The bipolar plate (152) is provided with a pressure detection channel, which is connected to the through hole (153). The axis of the pressure detection channel and the axis of the through hole (153) have an angle.

5. The gas-liquid separation and heat recovery device according to claim 3, characterized in that, The material of the bipolar plate insulating sheet (151) is at least one of polytetrafluoroethylene, polyetheretherketone, polyethylene, and polypropylene.

6. The gas-liquid separation and heat recovery device according to any one of claims 2-5, characterized in that, The gas-liquid separation and heat recovery device also includes a control circuit (3), which is electrically connected to the hydrogen pump unit (14) in a one-to-one correspondence. The control circuit (3) is configured to adjust the working voltage of the corresponding hydrogen pump unit (14).

7. The gas-liquid separation and heat recovery device according to any one of claims 2-5, characterized in that, The theoretical decomposition voltage of water electrolysis in the hydrogen pump unit (14) at the current temperature is defined as U1, and the working voltage of the hydrogen pump unit (14) is U2, where U2 < U1.

8. The gas-liquid separation and heat recovery device according to any one of claims 2-5, characterized in that, The electrochemical hydrogen pump (1) further includes an anode plate (16) and a cathode plate (17) arranged opposite to each other, and an insulating screw (18). The insulating screw (18) is fixedly connected to the anode plate (16) and the cathode plate (17). The hydrogen pump unit (14) is sandwiched between the anode plate (16) and the cathode plate (17). The anode plate (16) is close to the anode side of the first hydrogen pump unit (14) in the direction of hydrogen flow, and the cathode plate (17) is close to the cathode side of the last hydrogen pump unit (14) in the direction of hydrogen flow. The anode plate (16) is provided with a first flow channel on the end wall facing the hydrogen pump unit (14). One end of the first flow channel forms the mixed gas outlet (12), and the other end of the first flow channel forms the mixed gas inlet (11). The cathode end plate (17) facing the end wall of the hydrogen pump unit (14) is provided with a second flow channel (171), and one end of the second flow channel (171) forms the hydrogen outlet (13).

9. An electrolytic hydrogen production system, characterized in that, Includes the gas-liquid separation and heat recovery device according to any one of claims 1-8.

10. The electrolytic hydrogen production system according to claim 9, characterized in that, The steam ejector (2) has a fluid outlet (22) which is connected to the steam inlet of other devices in the electrolysis hydrogen production system.

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