Liquid hydrogen pressurization unit and liquid hydrogen pressurization system

Abstract

This invention relates to a liquid hydrogen pressurization device and system, belonging to the field of liquid hydrogen technology. The liquid hydrogen pressurization device includes interconnected liquid-phase pressurization pipelines, a pressurization vaporizer, and a gas-phase reflux pipeline, as well as a pneumatic control unit for controlling the liquid-phase pressurization pipelines. The pneumatic control unit includes a pneumatic regulating valve, a gas source pipeline, a differential pressure valve, and a feedback pipeline. The pneumatic regulating valve is a pneumatic-opening valve installed on the liquid-phase pressurization pipeline. One end of the gas source pipeline is connected to the pneumatic regulating valve, and the other end is used to connect to an external gas source device. The differential pressure valve is installed on the gas source pipeline. One end of the feedback pipeline is connected to the differential pressure valve, and the other end is connected to the liquid hydrogen container. The differential pressure valve can obtain the pressure inside the liquid hydrogen container through the feedback pipeline. When the pressure inside the liquid hydrogen container exceeds a preset pressure value, it cuts off the gas source pipeline, causing the pneumatic regulating valve to close, thereby terminating the pressurization process. This solves the technical problem that existing liquid hydrogen storage tanks are prone to exceeding pressure limits during pressurization.

Description

Technical Field

[0001] This invention relates to the field of liquid hydrogen technology, and in particular to a liquid hydrogen pressurization device and a liquid hydrogen pressurization system. Background Technology

[0002] Liquid hydrogen is a cryogenic liquid with extremely low temperatures. It is characterized by easy vaporization, flammability, explosiveness, and sensitivity of saturated vapor pressure to temperature changes. Therefore, relevant safety regulations must be strictly followed during operation.

[0003] Currently, when unloading liquid hydrogen between containers, a portion of the liquid hydrogen is typically drawn out and vaporized using a booster vaporizer, then returned to the tank to increase the pressure inside. The pressure difference is then used to transfer the liquid. This method is relatively common, but it requires high stability and safety in pressure control.

[0004] However, due to the low latent heat of vaporization and rapid pressure rise of liquid hydrogen, if the pressurization process lacks an effective linkage control mechanism, the pressure inside the tank can easily exceed the limit, causing the safety valve to trip or the rupture disc to activate. Once this happens, not only will there be media loss, but maintenance operations such as disassembly, purging, replacement, and calibration will also be required, which will significantly increase the maintenance workload and affect the normal operation and efficiency of the equipment. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problem that existing liquid hydrogen storage tanks are prone to exceeding the pressure limit during pressurization, which affects the normal operation of the equipment.

[0006] To address the aforementioned technical problems, this application provides a liquid hydrogen pressurization device for installation on a liquid hydrogen container. The liquid hydrogen pressurization device includes: a liquid phase pressurization pipeline, one end of which is connected to the liquid phase outlet of the liquid hydrogen container; a pressurized vaporizer having a first port and a second port, the first port being connected to the liquid phase pressurization pipeline for heating and vaporizing the incoming liquid hydrogen; a gas phase reflux pipeline, one end of which is connected to the second port of the pressurized vaporizer, and the other end being connected to the gas phase space within the liquid hydrogen container for refluxing the vaporized hydrogen back into the liquid hydrogen container to increase the pressure within the container; and a pneumatic control unit, including a pneumatic regulating valve, a gas source pipeline, a differential pressure valve, and a feedback pipeline; the pneumatic regulating valve is an air-to-open valve. The gas supply line is installed on the liquid phase pressurization pipeline to open or close it. One end of the gas supply line is connected to the pneumatic regulating valve, and the other end is connected to an external gas source device. The differential pressure valve is installed on the gas supply line to open or close it. One end of the feedback line is connected to the differential pressure valve, and the other end is connected to the liquid hydrogen container. The differential pressure valve can obtain the pressure inside the liquid hydrogen container through the feedback line, and when the pressure inside the liquid hydrogen container is lower than its preset pressure value, it opens the gas supply line to open the pneumatic regulating valve to start the pressurization process. When the pressure inside the liquid hydrogen container is higher than the preset pressure value, it closes the gas supply line to close the pneumatic regulating valve to terminate the pressurization process.

[0007] In some embodiments of this application, the pneumatic control unit further includes a pressure control valve disposed on the feedback line for isolating and cutting off the feedback line.

[0008] In some embodiments of this application, the liquid hydrogen pressurization device includes a liquid phase pipeline shut-off valve, which is disposed on the liquid phase pressurization pipeline and located at one end near the liquid hydrogen container.

[0009] In some embodiments of this application, the liquid hydrogen pressurization device includes a liquid phase pipeline safety valve, which is disposed on the liquid phase pressurization pipeline and located between the liquid phase pipeline shut-off valve and the pneumatic regulating valve, for venting protection of the liquid phase pressurization pipeline.

[0010] In some embodiments of this application, the liquid hydrogen pressurization device includes a purge valve, which is disposed on the liquid phase pressurization pipeline and located between the liquid phase pipeline shut-off valve and the pneumatic regulating valve; the purge valve is used to connect to an external purge device to introduce replacement gas.

[0011] In some embodiments of this application, the liquid hydrogen pressurization device includes a pressurization return valve, which is disposed on the gas phase reflux pipeline and located at one end near the pressurization vaporizer.

[0012] In some embodiments of this application, the liquid hydrogen pressurization device further includes a gas phase pipeline safety valve, which is disposed on the gas phase return pipeline and located between the pressurization return valve and the pressurization vaporizer.

[0013] In some embodiments of this application, the liquid hydrogen pressurization device further includes an active overpressure discharge unit; the active overpressure discharge unit includes a main discharge pipe, a main discharge port, and a manual discharge valve; one end of the main discharge pipe is connected to the liquid phase pressurization pipeline between the pneumatic regulating valve and the pressurization vaporizer, and the other end of the main discharge pipe is provided with the main discharge port; the manual discharge valve is disposed on the main discharge pipe; when the manual discharge valve is opened, the low-temperature hydrogen gas in the liquid hydrogen container is heated by heat exchange in the pressurization vaporizer and then discharged from the main discharge port.

[0014] In some embodiments of this application, the active overpressure emission unit further includes an auxiliary emission pipe, an auxiliary emission port, and an emission rupture disc; one end of the auxiliary emission pipe is connected to the main emission pipe, and the other end is provided with the auxiliary emission port; the emission rupture disc is disposed on the auxiliary emission pipe; when the main emission port of the main emission pipe is blocked and the system pressure rises to the burst pressure of the emission rupture disc, the emission rupture disc ruptures, allowing gas to be discharged through the auxiliary emission port.

[0015] In some embodiments of this application, the liquid hydrogen pressurization device further includes a passive overpressure discharge unit; the passive overpressure discharge unit includes a three-way valve and two sets of discharge branches, the inlet end of the three-way valve is connected to the gas phase reflux pipeline; the two sets of discharge branches are arranged in parallel on both sides of the three-way valve; one end of each set of discharge branches is connected to the outlet end of the three-way valve, and the other end is connected to the main discharge pipe.

[0016] In some embodiments of this application, each group of relief branches includes a pressure relief safety valve and a pressure relief rupture disc; the pressure relief safety valve and the pressure relief rupture disc of each group of relief branches are connected in parallel to relieve pressure through the pressure relief safety valve or the pressure relief rupture disc when the system pressure reaches different set values.

[0017] This application also provides a liquid hydrogen pressurization system, comprising: a liquid hydrogen container; and a liquid hydrogen pressurization device as described above, wherein the liquid hydrogen pressurization device is disposed on the liquid hydrogen container and is connected to the liquid phase outlet and the gas phase space of the liquid hydrogen container respectively, so that the liquid hydrogen is vaporized by the pressurization vaporizer and flows back into the liquid hydrogen container, thereby forming a pressurization cycle.

[0018] As can be seen from the above technical solution, the beneficial effects of the present invention are as follows:

[0019] This application provides a liquid hydrogen pressurization device and system. The liquid hydrogen pressurization device uses a pneumatic regulating valve on the liquid phase pressurization pipeline and a differential pressure valve to obtain the pressure signal inside the liquid hydrogen container in real time through a feedback pipeline, thereby forming an automatic linkage control mechanism based on the pressure change of the liquid hydrogen container. When the pressure inside the liquid hydrogen container is lower than the preset pressure value, the differential pressure valve opens the gas source pipeline, causing the pneumatic regulating valve to open. The liquid hydrogen is vaporized by the pressurization vaporizer and flows back into the container to achieve pressurization. When the pressure inside the container rises to the preset pressure value, the differential pressure valve automatically cuts off the gas source pipeline, causing the pneumatic regulating valve to close, thereby terminating the pressurization process in a timely manner.

[0020] The liquid hydrogen pressurization process can automatically adjust according to the container pressure status, effectively avoiding the problem of safety valve activation due to continuous pressure rise. This reduces media loss and maintenance workload caused by overpressure protection device activation, improving the stability and safety of liquid hydrogen container operation. Simultaneously, the control unit uses pneumatic components to achieve pressure feedback and valve linkage control, eliminating the need for electrical equipment. This reduces the safety hazards associated with using electrical components in the flammable and explosive hydrogen environment, further enhancing the system's inherent safety and operational reliability. Furthermore, since the pneumatic regulating valve is controlled through a gas supply pipeline, in the event of a system leak or other abnormal conditions, the pneumatic regulating valve can be quickly closed remotely by cutting off the gas supply, thereby achieving emergency shutdown of the liquid phase pressurization pipeline. This remote and rapid shutdown makes the system operation more flexible, safe, and controllable. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a liquid hydrogen pressurization system in one embodiment.

[0022] The annotations in the attached figures are explained as follows: 100. Liquid hydrogen pressurization system; 10. Liquid hydrogen container; 20. Liquid hydrogen pressurization device; 21. Liquid phase pressurization pipeline; 211. Liquid phase pipeline shut-off valve; 212. Liquid phase pipeline safety valve; 213. Purge valve; 22. Pressurization vaporizer; 221. First port; 222. Second port; 23. Gas phase reflux pipeline; 231. Pressurization return valve; 232. Gas phase pipeline safety valve; 24. Pneumatic control unit; 241. Pneumatic regulator 242. Valve; 243. Gas source pipeline; 244. Differential pressure valve; 245. Feedback pipeline; 246. Pressure control valve; 25. Active overpressure discharge unit; 251. Main discharge pipe; 252. Manual discharge valve; 253. Main discharge port; 254. Auxiliary discharge pipe; 255. Auxiliary discharge port; 256. Discharge rupture disc; 26. Passive overpressure discharge unit; 261. Three-way valve; 262. Pressure relief safety valve; 263. Pressure relief rupture disc. Detailed Implementation

[0023] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0024] In the description of this application, it should be understood that, in the embodiments shown in the accompanying drawings, the indications of direction or positional relationships (such as up, down, left, right, front, and back, etc.) are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the mechanism or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. These descriptions are appropriate when these elements are in the positions shown in the accompanying drawings. If the description of the positions of these elements changes, these directional indications also change accordingly.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] Please see Figure 1 This embodiment provides a liquid hydrogen pressurization system 100, which includes a liquid hydrogen container 10 and a liquid hydrogen pressurization device 20.

[0027] The liquid hydrogen container 10 can be a cryogenic insulated storage tank, which stores liquid hydrogen. The liquid hydrogen container 10 can be divided into a bottom liquid phase space and an upper gas phase space. A liquid phase outlet is provided at the bottom of the liquid hydrogen container 10 to draw out the liquid hydrogen. The upper part of the liquid hydrogen container 10 forms a gas phase space to contain the vaporized hydrogen and maintain the pressure inside the tank. A liquid hydrogen pressurization device 20 is installed on the liquid hydrogen container 10 and is connected to both the liquid phase outlet and the gas phase space, so that the liquid hydrogen, after being vaporized by the pressurized vaporizer 22, flows back into the liquid hydrogen container 10, thus forming a pressurized cycle.

[0028] Please see Figure 1 The liquid hydrogen pressurization device 20 in this embodiment includes a liquid phase pressurization pipeline 21, a pressurization vaporizer 22, a gas phase reflux pipeline 23, and a pneumatic control unit 24.

[0029] One end of the liquid phase pressurization line 21 is connected to the liquid phase outlet of the liquid hydrogen container 10. The pressurized vaporizer 22 has a first port 221 and a second port 222. The first port 221 is connected to the liquid phase pressurization line 21 and is used to heat and vaporize the incoming liquid hydrogen. One end of the gas phase reflux line 23 is connected to the second port 222 of the pressurized vaporizer 22, and the other end is connected to the gas phase space inside the liquid hydrogen container 10, for returning the vaporized hydrogen to the liquid hydrogen container 10 to increase the pressure inside the liquid hydrogen container 10.

[0030] The pneumatic control unit 24 includes a pneumatic regulating valve 241, a gas source pipeline 242, a differential pressure valve 243, and a feedback pipeline 244. The pneumatic regulating valve 241 is an air-to-open valve, installed on the liquid phase pressurization pipeline 21, used to open or close the liquid phase pressurization pipeline 21. One end of the gas source pipeline 242 is connected to the pneumatic regulating valve 241, and the other end is used to connect to an external gas source device. The differential pressure valve 243 is installed on the gas source pipeline 242, used to open or close the gas source pipeline 242; one end of the feedback pipeline 244 is connected to the differential pressure valve 243, and the other end is connected to the liquid hydrogen container 10.

[0031] The differential pressure valve 243 can obtain the pressure inside the liquid hydrogen container 10 through the feedback pipeline 244, and when the pressure inside the liquid hydrogen container 10 is lower than its preset pressure value, it opens the gas source pipeline 242 to open the pneumatic regulating valve 241 to start the pressurization process; when the pressure inside the liquid hydrogen container 10 is higher than the preset pressure value, it cuts off the gas source pipeline 242 to close the pneumatic regulating valve 241 to terminate the pressurization process.

[0032] Specifically, one end of the liquid phase pressurization line 21 is connected to the liquid phase outlet of the liquid hydrogen container 10, used to draw out the liquid hydrogen from the bottom of the container and transport it to the pressurized vaporizer 22. The liquid phase pressurization line 21 can be made of cryogenic stainless steel to adapt to the low-temperature conditions of liquid hydrogen at approximately -250°C, and to ensure that the system has good sealing and pressure resistance. The pressurized vaporizer 22 has a first port 221 and a second port 222 arranged opposite to each other, wherein the first port 221 is connected to the liquid phase pressurization line 21. When liquid hydrogen enters the pressurized vaporizer 22 from the liquid phase pressurization line 21, it exchanges heat with the ambient air or other heat sources through the heat exchange structure of the pressurized vaporizer 22 (e.g., heat exchange tube bundle or finned heat exchange structure), causing the incoming liquid hydrogen to absorb heat and rapidly vaporize into gaseous hydrogen. The second port 222 is used to transport the vaporized hydrogen to the gas phase reflux line 23. One end of the gas phase reflux line 23 is connected to the second port 222 of the booster vaporizer 22, and the other end is used to connect to the gas phase space inside the liquid hydrogen container 10. Through the gas phase reflux line 23, the vaporized hydrogen can re-enter the gas phase space of the liquid hydrogen container 10, thereby increasing the gas pressure inside the container and pressurizing the liquid hydrogen container 10.

[0033] The pneumatic control unit 24 is used to control the on / off state of the liquid phase pressurization pipeline 21 to achieve automatic adjustment of the pressurization process. The pneumatic regulating valve 241 of the pneumatic control unit 24 is installed on the liquid phase pressurization pipeline 21. The pneumatic regulating valve 241 adopts a pneumatic-opening structure, that is, when its actuator receives an external gas source, the valve opens, allowing liquid hydrogen to enter the pressurized vaporizer 22; when the external gas source is cut off, the pneumatic regulating valve 241 automatically closes under the action of elastic restoring force, thereby cutting off the liquid phase pressurization pipeline 21.

[0034] One end of the gas supply line 242 is connected to the actuator of the pneumatic regulating valve 241, and the other end is connected to an external gas source device (such as a compressed air system or a nitrogen-driven system) to provide driving gas to the pneumatic regulating valve 241. A differential pressure valve 243 is installed on the gas supply line 242 to control the on / off state of the gas supply line 242. One end of the feedback line 244 is connected to the differential pressure valve 243, and the other end is connected to the interior of the liquid hydrogen container 10 to transmit the pressure signal from inside the liquid hydrogen container 10 to the differential pressure valve 243.

[0035] During system operation, the differential pressure valve 243 can obtain real-time pressure information inside the liquid hydrogen container 10 through the feedback pipeline 244. When the pressure inside the liquid hydrogen container 10 is lower than the preset pressure value of the differential pressure valve 243, the differential pressure valve 243 opens the gas source pipeline 242, allowing gas to enter the actuator of the pneumatic regulating valve 241, thereby opening the pneumatic regulating valve 241. At this time, liquid hydrogen enters the liquid phase booster pipeline 21 from the liquid phase outlet of the liquid hydrogen container 10 and flows into the booster vaporizer 22 for heating and vaporization. The vaporized hydrogen gas flows back to the gas phase space of the liquid hydrogen container 10 through the gas phase return pipeline 23, thereby gradually increasing the pressure inside the container.

[0036] When the pressure inside the container rises to the preset pressure value of the differential pressure valve 243, the differential pressure valve 243 automatically cuts off the gas supply line 242, causing the pneumatic regulating valve 241 to close, thereby stopping the liquid hydrogen from entering the booster vaporizer 22 and terminating the boosting process. This allows the liquid hydrogen boosting device 20 to automatically adjust the flow rate of liquid hydrogen entering the booster vaporizer 22 according to the internal pressure state of the liquid hydrogen container 10, achieving automatic control of the boosting process.

[0037] Compared to traditional spring-loaded pressure boosting valves that rely on a spring structure to directly open or close the valve based on pressure changes to control pressurization, the traditional method has a smaller adjustment range and a fixed valve opening pressure, making it difficult to achieve flexible control. When the system pressure fluctuates significantly, it is prone to problems such as adjustment lag or frequent operation, thus affecting the stability of pressurization.

[0038] This embodiment uses a differential pressure valve 243, a feedback pipeline 244, and a pneumatic regulating valve 241 to form a pressure feedback control structure. This allows the valve's opening and closing to be directly adjusted according to changes in the internal pressure of the container, improving the stability and controllability of the pressurization process. Furthermore, this embodiment uses only pneumatic and mechanical components to achieve pressure feedback and control, eliminating the need for electrical equipment in a hydrogen environment. This reduces the safety hazards associated with using electrical components in flammable and explosive environments, thereby improving the system's safety.

[0039] Furthermore, since the pneumatic regulating valve 241 is driven and controlled by an external gas source, in the event of liquid hydrogen leakage or other abnormal operating conditions, the gas source can be remotely cut off or the gas source system can be remotely controlled to cause the pneumatic regulating valve 241 to close rapidly, thereby immediately cutting off the liquid phase pressurization pipeline 21 and achieving an emergency shutdown of the liquid hydrogen system. Therefore, the pneumatic regulating valve 241 can not only automatically stop pressurization when the set pressure is reached, but also be used as an emergency shut-off valve in emergencies, giving the system excellent remote control and emergency response capabilities, further improving the safety and operational reliability of the liquid hydrogen storage and transportation system.

[0040] Please see Figure 1 In some embodiments, the pneumatic control unit 24 further includes a pressure control valve 245, which is disposed on the feedback line 244 for isolating and cutting off the feedback line 244.

[0041] Specifically, the pressure control valve 245 is installed on the feedback line 244, located between the liquid hydrogen container 10 and the differential pressure valve 243, so that the pressure signal from the liquid hydrogen container 10 must pass through the pressure control valve 245 before being transmitted to the differential pressure valve 243.

[0042] The pressure control valve 245 can be a manually operated shut-off valve. When the pressure control valve 245 is in the open state, the pressure signal inside the liquid hydrogen container 10 can be smoothly transmitted to the differential pressure valve 243 via the feedback line 244, enabling the differential pressure valve 243 to sense the internal pressure of the container in real time and control the opening or closing of the pneumatic regulating valve 241 according to the pressure change. When the pressure control valve 245 is in the closed state, the feedback line 244 is cut off, and the pressure signal transmission channel between the differential pressure valve 243 and the liquid hydrogen container 10 is isolated.

[0043] By installing the pressure control valve 245 on the feedback line 244, when the system needs to be inspected or maintained, the pressure control valve 245 can be closed first, thereby isolating the pressure connection between the differential pressure valve 243 and the liquid hydrogen container 10. This allows the pneumatic control unit 24 to be disassembled, adjusted, or replaced without affecting the internal pressure state of the liquid hydrogen container 10, avoiding the pressure inside the container from directly acting on the control element and improving the safety of maintenance operations.

[0044] Please see Figure 1 In some embodiments, the liquid hydrogen pressurization device 20 includes a liquid phase line shut-off valve 211. The liquid phase line shut-off valve 211 is disposed on the liquid phase pressurization line 21 and located near one end of the liquid hydrogen container 10. Further, the liquid hydrogen pressurization device 20 includes a pressurization return valve 231, which is disposed on the gas phase reflux line 23 and located near one end of the pressurization vaporizer 22.

[0045] Specifically, the liquid phase pipeline shut-off valve 211 is located at the end of the liquid phase booster pipeline 21 near the liquid hydrogen container 10, that is, at the liquid phase outlet immediately adjacent to the liquid hydrogen container 10. The liquid phase pipeline shut-off valve 211 can be a cryogenic medium shut-off valve, ball valve, or gate valve structure. When the liquid phase pipeline shut-off valve 211 is open, liquid hydrogen can flow smoothly from the liquid hydrogen container 10 into the liquid phase booster pipeline 21 and enter the subsequent booster vaporizer 22 for vaporization; when the liquid phase pipeline shut-off valve 211 is closed, it can completely cut off the fluid passage between the liquid hydrogen container 10 and the liquid phase booster pipeline 21.

[0046] By installing the liquid phase pipeline shut-off valve 211 near the liquid hydrogen container 10, the liquid hydrogen source can be quickly cut off during system maintenance, equipment upkeep, or emergencies, thereby preventing liquid hydrogen from continuing to enter the booster vaporizer 22 and improving the safety of system operation and maintenance.

[0047] Correspondingly, a booster return valve 231 is also provided on the gas phase reflux pipeline 23. The booster return valve 231 is located at the end of the gas phase reflux pipeline 23 near the booster vaporizer 22, so that the hydrogen gas vaporized by the booster vaporizer 22 must pass through the booster return valve 231 before entering the liquid hydrogen container 10.

[0048] The booster return valve 231 can be a cryogenic shut-off valve or a one-way valve, and its valve body is also made of cryogenic material. When the booster return valve 231 is open, the hydrogen generated in the booster vaporizer 22 can flow smoothly back to the gas phase space of the liquid hydrogen container 10 through the gas phase return pipeline 23, thereby increasing the pressure inside the container; when the booster return valve 231 is closed, it can block the gas phase return channel.

[0049] By setting up the liquid phase pipeline shut-off valve 211 and the booster return valve 231, a dual control structure can be formed on the two key pipelines of liquid phase and gas phase, so that the liquid hydrogen booster system 100 has better operational flexibility and safety assurance capabilities in operation, maintenance and emergency conditions.

[0050] Please see Figure 1In some embodiments, the liquid hydrogen pressurization device 20 includes a liquid phase pipeline safety valve 212, which is disposed on the liquid phase pressurization pipeline 21 and located between the liquid phase pipeline shut-off valve 211 and the pneumatic regulating valve 241, for venting protection of the liquid phase pressurization pipeline 21.

[0051] Correspondingly, the liquid hydrogen pressurization device 20 also includes a gas phase pipeline safety valve 232, which is installed on the gas phase return pipeline 23 and located between the pressurization return valve 231 and the pressurization vaporizer 22.

[0052] Specifically, after liquid hydrogen flows out of the liquid phase outlet of the liquid hydrogen container 10, it passes through the liquid phase pipeline shut-off valve 211 and then continues to flow along the liquid phase pressurization pipeline 21. Before entering the pneumatic regulating valve 241, a liquid phase pipeline safety valve 212 is set so that the liquid phase pipeline safety valve 212 can protect the pressure state of the middle section of the liquid phase pressurization pipeline 21.

[0053] When the pressure in the liquid phase pressurization line 21 exceeds the preset opening pressure, the liquid phase line safety valve 212 opens, thus forming a venting channel, allowing some liquid hydrogen or its evaporated gas to be discharged into the safety discharge line. When the line pressure returns to the set range, the liquid phase line safety valve 212 automatically closes.

[0054] By installing the liquid phase pipeline safety valve 212 between the liquid phase pipeline shut-off valve 211 and the pneumatic regulating valve 241, the local pressure of the liquid phase boosting pipeline 21 can be protected in real time. In case of abnormal closure of the pneumatic regulating valve 241, pipeline blockage, or thermal expansion of liquid hydrogen, the pressure can be released in time, thereby preventing the pipeline and related equipment from being subjected to excessive pressure and improving the safety and reliability of the entire liquid hydrogen boosting system 100.

[0055] Correspondingly, a gas phase pipeline safety valve 232 is installed on the pipeline section between the booster vaporizer 22 and the booster return gas valve 231. The gas phase pipeline safety valve 232 can directly protect the gas pressure at the outlet section of the booster vaporizer 22. When the hydrogen pressure at the outlet section of the booster vaporizer 22 rises abnormally, the gas phase pipeline safety valve 232 can open in time to release the pressure and prevent the equipment from being damaged by pressure.

[0056] In this embodiment, the liquid phase pipeline safety valve 212 and the gas phase pipeline safety valve 232 independently protect the liquid phase booster pipeline 21 and the gas phase return pipeline 23, respectively, thereby forming a dual safety protection mechanism on the two key flow paths of liquid phase and gas phase, further improving the safety and stability of the liquid hydrogen booster device 20 during overall operation.

[0057] Please see Figure 1In some embodiments, the liquid hydrogen pressurization device 20 includes a purge valve 213. The purge valve 213 is disposed on the liquid phase pressurization line 21 and located between the liquid phase line shut-off valve 211 and the pneumatic regulating valve 241; the purge valve 213 is used to connect to an external purge device to introduce replacement gas.

[0058] Specifically, the valve body of the purge valve 213 is installed on the side wall of the liquid phase pressurization pipeline 21 by welding or threaded connection, and its outlet end is provided with an interface for connecting to external purging equipment, such as a quick connector or a standard pipe connector, so as to connect to a nitrogen source or other inert gas purging equipment.

[0059] By installing purge valve 213, the pipeline can be purged before equipment startup, after shutdown, or during maintenance. For example, before the system is put into operation for the first time or restarted, inert gases such as nitrogen can be introduced into the pipeline through purge valve 213 to replace and expel air, moisture, or other impurities in the pipeline. This prevents air from freezing or forming a flammable mixture in the low-temperature environment after entering the liquid hydrogen system, thereby improving the safety of system operation.

[0060] When the equipment is shut down or requires disassembly and maintenance, replacement gas can be introduced into the pipeline through the purge valve 213 to discharge residual hydrogen or cryogenic media and inertify them, thereby reducing the concentration of flammable gases inside the pipeline and reducing the risk of combustion or explosion during maintenance. After reinstallation and before being put into use, a second replacement with hydrogen is required to ensure operational safety. This makes the overall operation of the liquid hydrogen pressurization unit 20 safer and more controllable.

[0061] Please see Figure 1 In some embodiments, the liquid hydrogen pressurization device 20 further includes an active overpressure discharge unit 25. The active overpressure discharge unit 25 includes a main discharge pipe 251, a main discharge port 253, and a manual discharge valve 252.

[0062] One end of the main discharge pipe 251 is connected to the liquid phase pressurization pipeline 21 between the pneumatic regulating valve 241 and the pressurized vaporizer 22; the other end of the main discharge pipe 251 is provided with a main discharge port 253. A manual discharge valve 252 is provided on the main discharge pipe 251. When the manual discharge valve 252 is opened, the low-temperature hydrogen gas in the liquid hydrogen container 10 is heated by heat exchange in the pressurized vaporizer 22 and then discharged from the main discharge port 253.

[0063] Specifically, one end of the main discharge pipe 251 is connected to the liquid phase booster line 21, specifically at the pipe section between the pneumatic regulating valve 241 and the booster vaporizer 22; the other end of the main discharge pipe 251 extends outward from the system and has a main discharge port 253 at its end, used to guide the discharged gas to a safe area or discharge manifold. A manual discharge valve 252 is installed on the main discharge pipe 251 and located on the side of the main discharge pipe 251 close to the liquid phase booster line 21, so that the on / off state of the main discharge pipe 251 can be controlled by opening or closing the valve.

[0064] When the system is in normal automatic pressurization state, the manual discharge valve 252 remains closed. Liquid hydrogen enters the pressurization vaporizer 22 along the liquid phase pressurization pipeline 21 for vaporization, and returns to the gas phase space of the liquid hydrogen container 10 through the gas phase return pipeline 23, thereby realizing the pressure increase of the container.

[0065] When the internal pressure of the liquid hydrogen container 10 is too high and a rapid pressure reduction is needed, or when manual intervention is required during system commissioning, maintenance, pre-start venting, or under abnormal operating conditions, the operator can open the manual discharge valve 252. At this time, the cryogenic hydrogen in the liquid hydrogen container 10 flows in the reverse direction along the gas phase reflux pipeline 23 under pressure and enters the booster vaporizer 22. Heat exchange occurs in the booster vaporizer 22, further warming the cryogenic hydrogen before it enters the main discharge pipe 251 and is finally discharged to the outside of the system through the main discharge port 253.

[0066] Because the main discharge pipe 251 is connected between the pneumatic regulating valve 241 and the booster vaporizer 22, the discharged hydrogen gas can be heated by heat exchange through the booster vaporizer 22 during active discharge, thus preventing the direct discharge of cryogenic liquid hydrogen into the external environment. This effectively reduces the safety risks of frosting and material embrittlement that may occur with cryogenic discharge, thereby improving the safety and stability of the discharge process.

[0067] By connecting the main discharge pipe 251 to the liquid phase pressurization pipe 21 upstream of the pressurized vaporizer 22, the pressurized vaporizer 22 can simultaneously perform the functions of pressurization and vaporization and exhaust gas heating without adding additional heat exchange equipment, thus achieving reuse of the pressurized vaporizer 22. This structure not only simplifies the system piping layout and reduces the number of devices, but also reduces the overall system weight and manufacturing cost, while improving the integration and space utilization efficiency of the device.

[0068] Please see Figure 1In some embodiments, the active overpressure discharge unit 25 further includes an auxiliary discharge pipe 254, an auxiliary discharge port 255, and a discharge rupture disc 256. The auxiliary discharge pipe 254 is connected in parallel with the main discharge pipe 251. One end of the auxiliary discharge pipe 254 is connected to the main discharge pipe 251, and the other end is provided with the auxiliary discharge port 255. The discharge rupture disc 256 is disposed on the auxiliary discharge pipe 254. When the main discharge port 253 of the main discharge pipe 251 is blocked, causing the system pressure to rise to the burst pressure of the discharge rupture disc 256, the discharge rupture disc 256 ruptures, allowing gas to be discharged through the auxiliary discharge port 255.

[0069] Specifically, the auxiliary discharge pipe 254 can be branched off on the section of the main discharge pipe 251 near the manual discharge valve 252 and the main discharge port 253, so that the gas in the main discharge pipe 251 can simultaneously act on the auxiliary discharge pipe 254 under pressure. The discharge rupture disc 256 is installed on the auxiliary discharge pipe 254 and located in the middle of the auxiliary discharge pipe 254, and is used to automatically open the auxiliary discharge pipe 254 when the pressure exceeds the set value.

[0070] During normal system operation, the active overpressure discharge unit 25 primarily discharges pressure manually via the main discharge pipe 251 and the manual discharge valve 252. The auxiliary discharge pipe 254 remains in standby mode, with the discharge rupture disc 256 maintaining a complete seal to keep the auxiliary discharge channel closed and not participating in normal system operation. When the system requires active depressurization, the operator can open the manual discharge valve 252, allowing the hydrogen gas in the liquid hydrogen container 10 to enter the pressurized vaporizer 22 via the liquid phase pressurization pipeline 21 for heat exchange and temperature increase. Subsequently, it is discharged from the system through the main discharge pipe 251 and the main discharge port 253, thereby achieving manual adjustment of the container pressure.

[0071] Under certain abnormal operating conditions, such as when the main vent 253 becomes icy, blocked by foreign objects, or when the venting pipeline is unable to vent normally due to external conditions, the system pressure may continue to rise even if the manual vent valve 252 is opened. When the internal system pressure rises further and reaches the set burst pressure of the vent rupture disc 256, the vent rupture disc 256 will rupture instantaneously under pressure, thereby opening the auxiliary venting pipe 254 to form an emergency venting channel. At this time, the hydrogen in the system can bypass the blocked main vent 253, be quickly discharged through the auxiliary venting pipe 254, and finally be discharged to a safe area through the auxiliary vent 255, thereby preventing the system pressure from continuing to rise.

[0072] By installing an auxiliary discharge pipe 254 in parallel outside the main discharge pipe 251, and installing a discharge rupture disc 256 on the auxiliary discharge pipe 254, an automatically opening emergency discharge path can be provided in the event of failure or blockage of the main discharge pipe 251, enabling the system to have passive overpressure protection capabilities. This forms a multi-stage pressure protection mechanism, further enhancing the safety assurance capabilities during the operation of the device.

[0073] Please see Figure 1 In some embodiments, the liquid hydrogen pressurization device 20 further includes a passive overpressure discharge unit 26. The passive overpressure discharge unit 26 includes a three-way valve 261 and two sets of discharge branches. The inlet end of the three-way valve 261 is connected to the gas phase reflux pipeline 23; the two sets of discharge branches are arranged in parallel on both sides of the three-way valve 261; one end of each set of discharge branches is connected to the outlet end of the three-way valve 261, and the other end is connected to the main discharge pipe 251.

[0074] Furthermore, each set of venting branches includes a pressure relief safety valve 262 and a pressure relief rupture disc 263. The pressure relief safety valve 262 and the pressure relief rupture disc 263 are arranged in parallel and are both connected between the three-way valve 261 and the main discharge pipe 251, so as to relieve pressure through the pressure relief safety valve 262 or the pressure relief rupture disc 263 when the system pressure reaches different set values.

[0075] Specifically, the passive overpressure discharge unit 26 is used to automatically release pressure when the system pressure rises abnormally and without human intervention, thereby providing passive safety protection for the liquid hydrogen pressurization system 100.

[0076] The passive overpressure discharge unit 26 includes a three-way valve 261 and two sets of venting branches. The inlet end of the three-way valve 261 is connected to the gas phase return pipeline 23. The two sets of venting branches are arranged in parallel on both sides of the three-way valve 261. One end of each venting branch is connected to the corresponding outlet end of the three-way valve 261, and the other end is connected to the main discharge pipe 251 in the active overpressure discharge unit 25. The three-way valve 261 can control the gas to be discharged from either of its left or right venting branches.

[0077] Each relief branch includes a pressure relief safety valve 262 and a pressure relief rupture disc 263. The pressure relief safety valve 262 and the pressure relief rupture disc 263 are also connected in parallel, so that they can function separately under different pressure conditions.

[0078] When the liquid hydrogen pressurization system 100 is in normal operation, the passive overpressure discharge unit 26 is in a closed standby state, and the hydrogen in the gas phase return pipeline 23 returns normally to the gas phase space of the liquid hydrogen container 10. When the system pressure gradually increases due to increased external heat input, obstruction of the return channel, failure of the control valve, or other abnormal conditions, when the pressure reaches the set opening pressure of the pressure relief safety valve 262, the pressure relief safety valve 262 automatically opens, and a portion of the hydrogen is introduced into the main discharge pipe 251 for discharge through any of the discharge branches, thereby automatically relieving pressure. If the pressure continues to rise due to extreme operating conditions and the burst pressure of the pressure relief rupture disc 263 is reached, the pressure relief rupture disc 263 ruptures to form a larger discharge channel, allowing a large amount of gas to be discharged rapidly, thereby achieving the second stage of emergency pressure relief protection.

[0079] Through the above structure, the passive overpressure relief unit 26 can achieve graded automatic pressure relief protection at different pressure levels, enabling the system to have multi-level safety protection capabilities as the pressure gradually increases. Among them, the pressure relief safety valve 262 is responsible for conventional overpressure protection that can be repeatedly opened and closed, while the pressure relief rupture disc 263 provides a one-time large-flow rapid pressure relief under extreme overpressure conditions, thereby effectively preventing the system pressure from continuously rising and causing damage to the equipment.

[0080] The specific working process of the liquid hydrogen pressurization system 100 in this embodiment is as follows: Under normal pressurization conditions, first open the liquid phase pipeline shut-off valve 211 and the pressurization return valve 231 to connect the liquid phase outlet of the liquid hydrogen container 10 with the liquid phase pressurization pipeline 21, while keeping the gas phase return pipeline 23 unobstructed.

[0081] At this time, the pneumatic regulating valve 241 is open. Liquid hydrogen in the liquid hydrogen container 10, under the pressure inside the container, enters the liquid phase pressurization pipeline 21 through the liquid phase outlet and then enters the pressurization vaporizer 22 through the pneumatic regulating valve 241. Inside the pressurization vaporizer 22, the cryogenic liquid hydrogen exchanges heat with the external environment or heat exchange medium, causing the liquid hydrogen to vaporize and heat up to form hydrogen gas. The generated hydrogen gas then returns to the gas phase space of the liquid hydrogen container 10 through the gas phase reflux pipeline 23, thereby increasing the amount of gas inside the container and increasing the internal pressure, thus achieving the pressurization process of the liquid hydrogen container 10.

[0082] Under steady-state pressure conditions, the internal pressure of the liquid hydrogen container 10 is transmitted to the differential pressure valve 243 via the feedback pipeline 244. When the internal pressure of the liquid hydrogen container 10 is lower than the set value, the differential pressure valve 243 controls the pneumatic regulating valve 241 to remain open, allowing liquid hydrogen to enter the booster vaporizer 22 for vaporization, thereby continuously replenishing hydrogen to the gas phase space of the container to increase the pressure. When the internal pressure of the liquid hydrogen container 10 reaches or exceeds the set range, the differential pressure valve 243 adjusts the pneumatic regulating valve 241 to gradually decrease until it closes, thereby stopping liquid hydrogen from entering the booster vaporizer 22, maintaining the system within a stable pressure range, and realizing the automatic pressure regulation function.

[0083] When the pneumatic regulating valve 241 is closed and the operator needs to reduce the pressure of the liquid hydrogen container 10, perform system debugging, or perform venting operations, the manual discharge valve 252 in the active overpressure discharge unit 25 can be opened. At this time, the hydrogen in the liquid hydrogen container 10 enters the booster vaporizer 22 under pressure through the gas phase return pipeline 23, and after heat exchange and temperature increase in the booster vaporizer 22, it enters the main discharge pipe 251 and is finally discharged to the outside of the system through the main discharge port 253.

[0084] When the system experiences an abnormal pressure increase without manual intervention, the system can enter a passive pressure relief protection mode.

[0085] At this point, the passive overpressure relief unit 26 begins to function. High-pressure hydrogen from the gas phase return line 23 enters the three-way valve 261 and is distributed to any of the parallel-connected relief branches. When the system pressure rises to the first set pressure, the pressure relief safety valve 262 in the relief branch automatically opens first, allowing some high-pressure hydrogen to enter the main discharge pipe 251 through the corresponding relief branch and be discharged outside the system through the main discharge port 253, thus achieving the first stage of automatic pressure relief protection. If, in extreme cases, the system pressure continues to rise and reaches a higher set value, the pressure relief rupture disc 263 in the relief branch ruptures, forming a larger diameter discharge channel, allowing a large amount of hydrogen to quickly enter the main discharge pipe 251 and be discharged outside the system, achieving the second stage of rapid emergency pressure relief protection.

[0086] Meanwhile, when blockages occur in the liquid phase pressurization pipeline 21 and the gas phase return pipeline 23, causing abnormal increases in pipeline pressure, the liquid phase pipeline safety valve 212 and the gas phase pipeline safety valve 232 will automatically open when the set opening pressure is reached, allowing liquid hydrogen or vaporized gas in the pipeline to be introduced into the main discharge pipe 251 and discharged from the system, thereby preventing the pipeline from being subjected to excessive pressure.

[0087] In summary, this embodiment provides a liquid hydrogen pressurization device 20 and a liquid hydrogen pressurization system 100. The liquid hydrogen pressurization device 20 uses a pneumatic regulating valve 241 installed on the liquid phase pressurization pipeline 21 and a differential pressure valve 243 to obtain the pressure signal inside the liquid hydrogen container 10 in real time through the feedback pipeline 244, thereby forming an automatic linkage control mechanism based on the pressure change of the liquid hydrogen container 10. When the pressure inside the container is lower than the preset pressure value, the differential pressure valve 243 opens the gas source pipeline 242, causing the pneumatic regulating valve 241 to open. The liquid hydrogen is vaporized by the pressurization vaporizer 22 and flows back into the container to achieve pressurization. When the pressure inside the container rises to the preset pressure value, the differential pressure valve 243 automatically cuts off the gas source pipeline 242, causing the pneumatic regulating valve 241 to close, thereby terminating the pressurization process in a timely manner.

[0088] The liquid hydrogen pressurization process can automatically adjust according to the container pressure status, effectively avoiding the problem of safety valve tripping due to continuous pressure increase. This reduces media loss and maintenance workload caused by overpressure protection device activation, improving the stability and safety of the liquid hydrogen container 10. Simultaneously, the control unit uses pneumatic components to achieve pressure feedback and valve linkage control, eliminating the need for electrical equipment. This reduces the safety hazards associated with using electrical components in the flammable and explosive hydrogen environment, further enhancing the system's inherent safety and operational reliability. Furthermore, since the pneumatic regulating valve 241 is controlled via the gas supply pipeline 242, in the event of a system leak or other abnormal conditions, the pneumatic regulating valve 241 can be quickly closed remotely by cutting off the gas supply, thereby achieving emergency shutdown of the liquid phase pressurization pipeline 21. This remote and rapid shutdown makes the system operation more flexible, safe, and controllable.

[0089] Although the invention has been described with reference to several typical embodiments, it should be understood that the terminology used is illustrative and exemplary, and not restrictive. Since the invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A liquid hydrogen pressurization device, for installation on a liquid hydrogen container, characterized in that, The liquid hydrogen pressurization device includes: A liquid phase pressurization pipeline, one end of which is connected to the liquid phase outlet of the liquid hydrogen container; A booster vaporizer has a first port and a second port, the first port being connected to the liquid phase booster pipeline for heating and vaporizing incoming liquid hydrogen. A gas phase reflux pipeline has one end connected to the second port of the booster vaporizer and the other end connected to the gas phase space inside the liquid hydrogen container, which is used to reflux the vaporized hydrogen back into the liquid hydrogen container to increase the pressure inside the liquid hydrogen container. A pneumatic control unit includes a pneumatic regulating valve, a gas source pipeline, a differential pressure valve, and a feedback pipeline. The pneumatic regulating valve is an air-to-open valve, installed on the liquid phase pressurization pipeline, used to open or close the liquid phase pressurization pipeline. One end of the gas source pipeline is connected to the pneumatic regulating valve, and the other end is connected to an external gas source device. The differential pressure valve is installed on the gas source pipeline, used to open or close the gas source pipeline. One end of the feedback pipeline is connected to the differential pressure valve, and the other end is connected to the liquid hydrogen container. The differential pressure valve can obtain the pressure inside the liquid hydrogen container through the feedback pipeline, and when the pressure inside the liquid hydrogen container is lower than its preset pressure value, it can open the gas source pipeline to open the pneumatic regulating valve to start the pressurization process; when the pressure inside the liquid hydrogen container is higher than the preset pressure value, it can cut off the gas source pipeline to close the pneumatic regulating valve to terminate the pressurization process.

2. The liquid hydrogen pressurization device according to claim 1, characterized in that, The pneumatic control unit also includes a pressure control valve, which is disposed on the feedback line and is used to isolate and cut off the feedback line.

3. The liquid hydrogen pressurization device according to claim 1, characterized in that, The liquid hydrogen pressurization device includes a liquid phase pipeline shut-off valve, which is installed on the liquid phase pressurization pipeline and located at one end near the liquid hydrogen container.

4. The liquid hydrogen pressurization device according to claim 3, characterized in that, The liquid hydrogen pressurization device includes a liquid phase pipeline safety valve, which is installed on the liquid phase pressurization pipeline and located between the liquid phase pipeline shut-off valve and the pneumatic regulating valve, for the purpose of venting and protecting the liquid phase pressurization pipeline.

5. The liquid hydrogen pressurization device according to claim 3, characterized in that, The liquid hydrogen pressurization device includes a purge valve, which is installed on the liquid phase pressurization pipeline and located between the liquid phase pipeline shut-off valve and the pneumatic regulating valve; the purge valve is used to connect to an external purge device to introduce replacement gas.

6. The liquid hydrogen pressurization device according to claim 1, characterized in that, The liquid hydrogen pressurization device includes a pressurization return valve, which is installed on the gas phase reflux pipeline and located at one end near the pressurization vaporizer.

7. The liquid hydrogen pressurization device according to claim 6, characterized in that, The liquid hydrogen pressurization device also includes a gas phase pipeline safety valve, which is installed on the gas phase return pipeline and located between the pressurization return valve and the pressurization vaporizer.

8. The liquid hydrogen pressurization device according to any one of claims 1-7, characterized in that, The liquid hydrogen pressurization device also includes an active overpressure discharge unit; the active overpressure discharge unit includes a main discharge pipe, a main discharge port, and a manual discharge valve; one end of the main discharge pipe is connected to the liquid phase pressurization pipeline between the pneumatic regulating valve and the pressurization vaporizer, and the other end of the main discharge pipe is provided with the main discharge port; the manual discharge valve is installed on the main discharge pipe; when the manual discharge valve is opened, the low-temperature hydrogen gas in the liquid hydrogen container is heated by heat exchange in the pressurization vaporizer and then discharged from the main discharge port.

9. The liquid hydrogen pressurization device according to claim 8, characterized in that, The active overpressure emission unit also includes an auxiliary emission pipe, an auxiliary emission port, and an emission rupture disc; one end of the auxiliary emission pipe is connected to the main emission pipe, and the other end is provided with the auxiliary emission port; the emission rupture disc is disposed on the auxiliary emission pipe. When the main discharge port of the main discharge pipe becomes blocked and the system pressure rises to the burst pressure of the discharge rupture disc, the discharge rupture disc ruptures, allowing the gas to be discharged through the auxiliary discharge port.

10. The liquid hydrogen pressurization device according to claim 8, characterized in that, The liquid hydrogen pressurization device also includes a passive overpressure discharge unit; the passive overpressure discharge unit includes a three-way valve and two sets of discharge branches, the inlet end of the three-way valve is connected to the gas phase reflux pipeline; the two sets of discharge branches are arranged in parallel on both sides of the three-way valve; one end of each set of discharge branches is connected to the outlet end of the three-way valve, and the other end is connected to the main discharge pipe.

11. The liquid hydrogen pressurization device according to claim 10, characterized in that, Each of the relief branches includes a pressure relief safety valve and a pressure relief rupture disc; the pressure relief safety valve and the pressure relief rupture disc of each relief branch are connected in parallel to relieve pressure through the pressure relief safety valve or the pressure relief rupture disc when the system pressure reaches different set values.

12. A liquid hydrogen pressurization system, characterized in that, include: liquid hydrogen container; The liquid hydrogen pressurization device according to any one of claims 1-11, wherein the liquid hydrogen pressurization device is disposed on the liquid hydrogen container and is respectively connected to the liquid phase outlet and the gas phase space of the liquid hydrogen container, so that the liquid hydrogen is vaporized by the pressurization vaporizer and flows back into the liquid hydrogen container, thereby forming a pressurization cycle.

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