Liquid hydrogen refueling station system and method of operation

Abstract

The present application relates to a kind of liquid hydrogen hydrogenation station systems and operating method, system includes the liquid hydrogen source, second liquid hydrogen booster pump, second liquid hydrogen booster pump outlet control valve, temperature tank, hydrogen dispenser, one end is connected between liquid hydrogen source and second liquid hydrogen booster pump, the other end is connected to temperature tank, liquid hydrogen gasification pipeline, first liquid hydrogen booster pump, first liquid hydrogen booster pump outlet control valve, gasifier, hydrogen storage bottle group are sequentially arranged in liquid hydrogen gasification pipeline, and two ends are respectively connected with the outlet pipeline of second liquid hydrogen booster pump, the outlet pipeline of first liquid hydrogen booster pump Parallel pipeline of double pump, parallel pipeline is equipped with parallel pipeline low-temperature liquid hydrogen control valve on it.Compared with prior art, two parallel liquid hydrogen booster pumps are used to access system in the present application, according to the hydrogenation scene and demand of liquid hydrogen hydrogenation station, the requirements of different use scenarios and hydrogenation flow are met by controlling low-temperature liquid hydrogen valve and the inlet and outlet flow of liquid hydrogen booster pump and the way of pipeline connection.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen energy and fuel cell vehicle technology, and relates to a liquid hydrogen refueling station system and its operation method. Background Technology

[0002] Vigorously developing hydrogen energy is one of the important measures to achieve energy structure transformation and sustainable development. Hydrogen refueling stations are the infrastructure for replenishing energy for hydrogen energy utilization equipment such as hydrogen fuel cells, and an important prerequisite for the promotion and application of fuel cell vehicles and the accelerated development of the hydrogen energy industry. According to the relevant plan of the "Energy Saving and New Energy Vehicle Technology Roadmap 2.0" revised and compiled by the China Society of Automotive Engineers under the guidance of the Ministry of Industry and Information Technology on October 27, 2020, my country aims to build at least 1,000 hydrogen refueling stations by 2025 and at least 5,000 by 2035.

[0003] Depending on the hydrogen storage state within the station, hydrogen refueling stations are divided into gaseous hydrogen refueling stations and liquid hydrogen refueling stations. Liquid hydrogen refueling stations have the advantage of high storage and transportation efficiency. Utilizing a direct pressurization and vaporization technology, they can significantly reduce the operating energy consumption of hydrogen refueling stations, representing the future development trend of low-energy, large-scale hydrogen refueling stations. According to H2Stations' global hydrogen refueling station statistics report, as of 2021, more than 800 hydrogen refueling stations had been built worldwide, 30% of which were liquid hydrogen refueling stations, mainly distributed in the United States, Europe, and Japan. LINDE, a German company, is a pioneer in the research, application, and promotion of liquid hydrogen refueling stations. Their liquid hydrogen pressurization and vaporization refueling station built in Oakland (CA), USA, has an on-site hydrogen storage capacity of 800 kg and a refueling capacity exceeding 40 kg / h (~0.67 kg / min), capable of simultaneously meeting hydrogen refueling requirements at 35 MPa and 70 MPa. However, due to a series of issues such as liquid hydrogen production, storage, transportation, and safety, my country's research on liquid hydrogen refueling stations is still in its early stages, with immature key equipment technologies and insufficient safety performance assessments.

[0004] Liquid hydrogen refueling stations need to vaporize liquid hydrogen before adding hydrogen gas, releasing a significant amount of usable cold energy. However, existing liquid hydrogen refueling stations abroad, such as the Ariake refueling station in Tokyo, Japan, and the numerous liquid hydrogen refueling stations built by Plug Power for Walmart and Amazon in the United States, all use ambient air vaporizers. In these vaporizers, liquid hydrogen exchanges heat with air and vaporizes, gaining heat, while the air gains cold energy which is then released into the atmosphere, resulting in a waste of cold energy. Authorization numbers CN113531388 B and CN112682691 B take into account the significant amount of cold energy wasted during liquid hydrogen vaporization and design cold energy recovery systems to recover this energy. However, this method of cold energy recovery is inefficient; with high-flow refueling and limited maximum cold storage capacity in the cold tank, the recovered cold energy is insufficient to pre-cool large flows of high-pressure, ambient-temperature gaseous hydrogen. Linde, a German company, also uses a method of blending gaseous and liquid hydrogen to utilize the cold energy of liquid hydrogen. However, it is difficult to precisely control the temperature to the -40°C pre-cooling refueling temperature specified in the SAE-J2601 refueling protocol. Therefore, designing a thermal management system that can effectively utilize the cold energy of liquid hydrogen to pre-cool the input hydrogen to the hydrogen dispenser has high practical application value.

[0005] Limited by the development level of key equipment, the output flow rate of liquid hydrogen booster pumps used in current liquid hydrogen refueling stations is not high. For example, the output flow rate of liquid hydrogen booster pumps from Linde AG in Germany is 50-70 kg / h, or ~1 kg / min. The performance indicator for liquid hydrogen booster pumps set in the 2022 National Key Project Guidelines for Hydrogen Energy Technology (2.1) of the Ministry of Science and Technology of my country, "Research and Development of Key Equipment for Liquid Hydrogen Refueling Stations," is also 60 kg / h (1 kg / min). However, with the large-scale operation of heavy-duty trucks and other large-capacity fuel cell commercial vehicles (hydrogen storage ≥40 kg), higher requirements are being placed on the rapid refueling of hydrogen refueling stations. The 2022 National Key Project Guidelines for Hydrogen Energy Technology (2.1) of the Ministry of Science and Technology sets a maximum refueling rate of ≥7.2 kg / min, but existing liquid hydrogen refueling station systems cannot meet the demand for rapid refueling. Summary of the Invention

[0006] The purpose of this invention is to provide a liquid hydrogen refueling station system and operation method, which includes a liquid hydrogen storage, pressurization and vaporization system equipped with dual liquid hydrogen booster pumps and a thermal management system. This allows the liquid hydrogen refueling station to meet the demand for rapid hydrogen refueling even when using existing liquid hydrogen booster pumps, by using the system structure designed in this invention, and can effectively utilize the cold energy of liquid hydrogen, thereby achieving energy conservation and emission reduction.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] A liquid hydrogen refueling station system, including

[0009] The liquid hydrogen source, the second liquid hydrogen booster pump, the outlet control valve of the second liquid hydrogen booster pump, the temperature mixing tank, the heat exchanger, and the hydrogen dispenser are connected in series.

[0010] The liquid hydrogen vaporization pipeline is connected at one end between the liquid hydrogen source and the second liquid hydrogen booster pump, and at the other end to the temperature mixing tank.

[0011] The first liquid hydrogen booster pump, the first liquid hydrogen booster pump outlet control valve, the vaporizer, and the hydrogen storage mechanism are connected in series on the liquid hydrogen vaporization pipeline.

[0012] A dual-pump parallel pipeline, with its two ends connected to the outlet pipelines of the second liquid hydrogen booster pump and the first liquid hydrogen booster pump respectively, is provided with a parallel pipeline cryogenic liquid hydrogen control valve; and,

[0013] The cold source is connected to the heat exchanger for heat exchange.

[0014] Furthermore, the liquid hydrogen source includes liquid hydrogen tank trucks and / or liquid hydrogen storage tanks.

[0015] Furthermore, the vaporizer includes a bare tube vaporizer and a finned tube vaporizer arranged in series.

[0016] Furthermore, safety relief valves are also provided at the outlets of the first liquid hydrogen booster pump and the second liquid hydrogen booster pump.

[0017] Furthermore, hydrogen pressure sensors and / or hydrogen temperature sensors are also provided at the outlets of the first liquid hydrogen booster pump and the second liquid hydrogen booster pump.

[0018] Furthermore, the hydrogen storage mechanism includes multiple hydrogen storage cylinders or groups of hydrogen storage cylinders arranged in parallel and having different pressure levels, which can be referred to as hydrogen storage cylinders (groups).

[0019] An operation method for a liquid hydrogen refueling station system based on the above includes:

[0020] Hydrogen replenishment mode: Open the outlet control valve of the first liquid hydrogen booster pump and the parallel pipeline cryogenic liquid hydrogen control valve, close the outlet control valve of the second liquid hydrogen booster pump. The second liquid hydrogen booster pump is set in parallel with the first liquid hydrogen booster pump, and the liquid hydrogen in the liquid hydrogen source is boosted and then fed into the vaporizer for heating and vaporization, and then fed into the hydrogen storage mechanism for storage.

[0021] An operation method for a liquid hydrogen refueling station system based on the above includes:

[0022] First hydrogen refueling mode: Open the outlet control valves of the first liquid hydrogen booster pump and the second liquid hydrogen booster pump, and close the parallel pipeline cryogenic liquid hydrogen control valve. The first liquid hydrogen booster pump pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the vaporizer for heating and vaporization. The second liquid hydrogen booster pump pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the temperature mixing tank, where it mixes with the vaporized hydrogen released by the hydrogen storage mechanism to obtain hydrogen within the set temperature range. Then, hydrogen is added to the outside through the hydrogen dispenser.

[0023] An operation method for a liquid hydrogen refueling station system based on the above includes:

[0024] Second hydrogen refueling mode: Open the parallel pipeline cryogenic liquid hydrogen control valve and the outlet control valve of the second liquid hydrogen booster pump, close the outlet control valve of the first liquid hydrogen booster pump, the second liquid hydrogen booster pump and the first liquid hydrogen booster pump are set in parallel, and the liquid hydrogen in the liquid hydrogen source is pressurized and input into the temperature mixing tank, and mixed with the vaporized hydrogen released by the hydrogen storage mechanism to obtain hydrogen within the set temperature range, and then hydrogen is added to the outside through the hydrogen dispenser.

[0025] An operation method for a liquid hydrogen refueling station system based on the above includes:

[0026] The third hydrogen refueling mode: The parallel pipeline cryogenic liquid hydrogen control valve and the second liquid hydrogen booster pump outlet control valve are opened, while the first liquid hydrogen booster pump outlet control valve is closed. The second liquid hydrogen booster pump is connected in parallel with the first liquid hydrogen booster pump, pressurizing the liquid hydrogen from the liquid hydrogen source and inputting it into the temperature mixing tank. There, it mixes with the vaporized hydrogen released from the hydrogen storage mechanism, and then passes through a heat exchanger for temperature adjustment to obtain hydrogen within a set temperature range. Finally, hydrogen is added externally via a hydrogen dispenser. The cold source can be a cold box or a refrigeration unit.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1) This invention addresses the issue that the highest flow rate achievable by current domestic liquid hydrogen booster pumps cannot meet the rapid hydrogen refueling needs of liquid hydrogen refueling stations. It innovatively proposes a dual-pump parallel hydrogen supply strategy, using two parallel liquid hydrogen booster pumps connected to the system. Depending on the different refueling scenarios and requirements of liquid hydrogen refueling stations, the inlet and outlet flow rates of the cryogenic liquid hydrogen valve and the liquid hydrogen booster pumps, as well as the pipeline connections, are controlled to meet the requirements of different usage scenarios and hydrogen refueling flow rates. This allows existing low-output flow rate (~1 kg / min) liquid hydrogen booster pumps to meet the rapid hydrogen refueling needs (≥7.2 kg / min) of liquid hydrogen refueling stations, contributing to the widespread application of liquid hydrogen refueling stations.

[0029] 2) This invention further optimizes the control strategy for blending temperature. By providing cold energy through a cold source, the temperature of the gas after blending temperature can be finely adjusted, thereby better controlling the pre-cooling temperature before hydrogen refueling. At the same time, for the application scenario of peak hydrogen flow rate, the cold energy of liquid hydrogen provided by two liquid hydrogen booster pumps alone cannot meet the requirement that the temperature of the hydrogen after blending reaches -40℃. Therefore, the refrigerant in the cold source needs to provide the cold energy required for further cooling.

[0030] 3) Different control strategies for liquid hydrogen booster pumps and cryogenic liquid hydrogen valves are set according to different application scenarios and requirements, which further improves the utilization efficiency of liquid hydrogen booster pumps and liquid hydrogen storage pressurization and vaporization systems, reduces the frequent start-up and shutdown of liquid hydrogen booster pumps, and helps to extend the service life of liquid hydrogen booster pumps. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a liquid hydrogen refueling station system with dual liquid hydrogen booster pumps and a thermal management system in Example 1;

[0032] Explanation of markings in the diagram:

[0033] 1. Liquid hydrogen tanker truck; 2. Liquid hydrogen storage tank; 3. First liquid hydrogen booster pump; 4. Second liquid hydrogen booster pump; 5. First liquid hydrogen booster pump outlet control valve; 6. Parallel pipeline cryogenic liquid hydrogen control valve; 7. Second liquid hydrogen booster pump outlet control valve; 8. Vaporizer; 81. Plain tube vaporizer; 82. Finned tube vaporizer; 9. Hydrogen storage mechanism; 10. Cold source output channel; 11. Cold source; 12. Heat exchanger; 13. Temperature mixing tank; 14. Hydrogen dispenser; 15. First liquid hydrogen booster pump input pipeline; 16. Second liquid hydrogen booster pump input pipeline; 17. First liquid hydrogen booster pump output pipeline; 18. Second liquid hydrogen booster pump output pipeline; 19. Dual pump parallel pipeline. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 The liquid hydrogen refueling station system shown includes a liquid hydrogen source, a second liquid hydrogen booster pump 4, a second liquid hydrogen booster pump outlet control valve 7, a temperature mixing tank 13, and a hydrogen dispenser 14, which are connected in series on the main pipeline; a liquid hydrogen vaporization pipeline with one end connected between the liquid hydrogen source and the second liquid hydrogen booster pump 4 and the other end connected to the temperature mixing tank 13; a first liquid hydrogen booster pump 3, a first liquid hydrogen booster pump outlet control valve 5, a vaporizer 8, a hydrogen storage mechanism 9, and a dual-pump parallel pipeline 19, which are connected in series on the liquid hydrogen vaporization pipeline.

[0036] In some specific embodiments, the main pipeline includes a second liquid hydrogen booster pump input pipeline 16, a second liquid hydrogen booster pump output pipeline 18, and a cold source output channel 10 connected in sequence.

[0037] In some specific embodiments, the two ends of the dual-pump parallel pipeline 19 are respectively connected to the output pipeline 18 of the second liquid hydrogen booster pump and the output pipeline 17 of the first liquid hydrogen booster pump, and the dual-pump parallel pipeline 19 is provided with a parallel pipeline cryogenic liquid hydrogen control valve 6.

[0038] In some specific embodiments, the liquid hydrogen source includes a liquid hydrogen tanker truck 1 and / or a liquid hydrogen storage tank 2. The liquid hydrogen tanker truck 1 can be used as a liquid hydrogen source alone, or to replenish the liquid hydrogen storage tank 2, or together with the liquid hydrogen storage tank 2 as a liquid hydrogen source.

[0039] In some specific embodiments, the vaporizer 8 includes a bare tube vaporizer 8 and a finned tube vaporizer 8 arranged in series to heat and vaporize liquid hydrogen in stages.

[0040] In some specific embodiments, safety relief valves are also provided at the outlet of the first liquid hydrogen booster pump 3 and the outlet of the second liquid hydrogen booster pump 4.

[0041] In some specific embodiments, hydrogen pressure sensors and / or hydrogen temperature sensors are also provided at the outlet of the first liquid hydrogen booster pump 3 and the outlet of the second liquid hydrogen booster pump 4.

[0042] In some specific embodiments, the hydrogen storage mechanism 9 includes multiple hydrogen storage cylinders or groups of hydrogen storage cylinders arranged in parallel and having different pressure levels.

[0043] In some specific embodiments, the second liquid hydrogen booster pump 4, the outlet control valve 7 of the second liquid hydrogen booster pump, the temperature sensor in the mixing tank 13, the first liquid hydrogen booster pump 3, the outlet control valve 5 of the first liquid hydrogen booster pump, and the parallel pipeline cryogenic liquid hydrogen control valve 6 are all electrically connected to the central processing unit to coordinate and control the mixing ratio of gaseous hydrogen and liquid hydrogen, achieving precise and efficient regulation of the dosing rate and temperature.

[0044] The system's central processing unit can adjust the state of the cryogenic liquid hydrogen valves in the outlet pipelines of the two liquid hydrogen pumps according to different application scenarios, hydrogen refueling requirements, and the current operating status of the station, thereby achieving different control strategies to meet the needs of different application scenarios.

[0045] An operation method for a liquid hydrogen refueling station system includes at least one of the following modes:

[0046] Hydrogen replenishment mode: Open the outlet control valve 5 of the first liquid hydrogen booster pump and the parallel pipeline cryogenic liquid hydrogen control valve 6, close the outlet control valve 7 of the second liquid hydrogen booster pump, set the second liquid hydrogen booster pump 4 and the first liquid hydrogen booster pump 3 in parallel, and input the liquid hydrogen in the liquid hydrogen source into the vaporizer 8 for heating and vaporization, and then input it into the hydrogen storage cylinder group 9 for storage.

[0047] In some specific embodiments, the hydrogen replenishment mode can be activated when there is no hydrogen refueling demand for hydrogen fuel cell vehicles at the liquid hydrogen refueling station, and when it is necessary to replenish the hydrogen storage cylinders in the high-pressure hydrogen storage cylinder group that have not reached the rated pressure.

[0048] In some specific embodiments, the hydrogen replenishment mode can replenish the hydrogen storage cylinders (groups) of different pressure levels of the hydrogen storage mechanism 9 one by one: after the pressure in the current high-pressure hydrogen storage cylinder (group) reaches the rated pressure, switch to the next high-pressure hydrogen storage cylinder (group) for replenishment, or stop.

[0049] First hydrogenation mode: Open the outlet control valve 5 of the first liquid hydrogen booster pump and the outlet control valve 7 of the second liquid hydrogen booster pump, close the parallel pipeline cryogenic liquid hydrogen control valve 6, the first liquid hydrogen booster pump 3 pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the vaporizer 8 for heating and vaporization, the second liquid hydrogen booster pump 4 pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the temperature mixing tank 13, and mixes it with the vaporized hydrogen to obtain hydrogen within the set temperature range, and then adds hydrogen to the outside through the hydrogen dispenser 14;

[0050] In some specific embodiments, the first hydrogen refueling mode can be activated when a liquid hydrogen refueling station needs to refuel a hydrogen fuel cell vehicle, but the hydrogen refueling flow rate is not high, for example, when the hydrogen refueling flow rate is less than or equal to 3.36 kg / min.

[0051] In some specific embodiments, after passing through the vaporizer 8, the liquid hydrogen is vaporized into gaseous hydrogen and stored in the high-pressure hydrogen storage cylinder group 9. The second liquid hydrogen booster pump 4 compresses the liquid hydrogen to a high pressure, and the high-pressure hydrogen storage cylinder group outputs gaseous hydrogen at room temperature and pressure. Based on the temperature sensor, the temperature of the hydrogen at the two locations is detected and uploaded to the system's central processing unit. The flow rates of the cryogenic liquid hydrogen and the room-temperature gaseous hydrogen are adjusted through the system's control strategy. They are mixed and heated in the temperature mixing tank 13 to maintain their temperature within a suitable range before entering the hydrogen dispenser for hydrogen addition, thus completing the entire hydrogen addition process.

[0052] Second hydrogen refueling mode: Open the parallel pipeline cryogenic liquid hydrogen control valve 6 and the second liquid hydrogen booster pump outlet control valve 7, close the first liquid hydrogen booster pump outlet control valve 5, the second liquid hydrogen booster pump 4 and the first liquid hydrogen booster pump 3 are connected in parallel, and the liquid hydrogen in the liquid hydrogen source is boosted and input into the temperature mixing tank 13, and mixed with the vaporized hydrogen released from the hydrogen storage cylinder group 9 to obtain hydrogen within the set temperature range, and then hydrogen is added to the outside through the hydrogen refueling machine 14;

[0053] In some specific embodiments, the second hydrogen refueling mode can be activated when the liquid hydrogen refueling station needs to refuel the hydrogen fuel cell vehicle and the hydrogen refueling flow rate is relatively large, for example: when the hydrogen refueling flow rate is greater than 3.5 kg / min and less than or equal to 7.0 kg / min.

[0054] In some specific embodiments, after passing through the vaporizer 8, the liquid hydrogen is vaporized into gaseous hydrogen and stored in the high-pressure hydrogen storage cylinder group 9; two liquid hydrogen booster pumps output high-pressure cryogenic liquid hydrogen. Based on the temperature sensors detecting the temperature of the hydrogen at two locations, the data is uploaded to the system's central processing unit. The system's control strategy adjusts the flow rates of cryogenic hydrogen and room-temperature hydrogen, and they are mixed and heated inside the temperature mixing tank 13 to maintain their temperature within a suitable range before entering the hydrogen dispenser for hydrogenation, completing the entire hydrogenation process.

[0055] The third hydrogen refueling mode: A heat exchanger 12 is also provided between the temperature exchange tank 13 and the hydrogen refueling machine 14. The heat exchanger 12 is connected to the cold source 11 through the parallel cold source output channel 10. The third hydrogen refueling mode includes: opening the parallel pipeline cryogenic liquid hydrogen control valve 6 and the second liquid hydrogen booster pump outlet control valve 7, closing the first liquid hydrogen booster pump outlet control valve 5, the second liquid hydrogen booster pump 4 and the first liquid hydrogen booster pump 3 are connected in parallel, and the liquid hydrogen in the liquid hydrogen source is boosted and input into the temperature exchange tank 13, and mixed with the vaporized hydrogen released by the hydrogen storage mechanism 9. Then, the temperature is adjusted by the heat exchanger 12 to obtain hydrogen within the set temperature range, and then hydrogen is added to the outside through the hydrogen refueling machine 14.

[0056] In some specific embodiments, the third hydrogen refueling mode can be activated when the liquid hydrogen refueling station needs to refuel the hydrogen fuel cell vehicle and the hydrogen refueling flow rate is large, for example, when the hydrogen refueling flow rate is greater than 6.72 kg / min.

[0057] In some specific embodiments, the high-pressure cryogenic liquid hydrogen output from the two liquid hydrogen booster pumps flows to the temperature mixing tank 13, while the high-pressure hydrogen storage mechanism outputs room-temperature and same-pressure gaseous hydrogen. The temperature of the hydrogen at the two locations is detected by temperature sensors and uploaded to the central processing unit of the system. The flow rates of cryogenic hydrogen and room-temperature hydrogen are adjusted through the system's control strategy, and they are mixed and temperature-matched inside the temperature mixing tank 13. The temperature of the mixed gaseous hydrogen is then further adjusted by the heat exchanger 12 to keep it within a suitable range before entering the hydrogen dispenser for hydrogen addition, thus completing the entire hydrogen addition process.

[0058] The following embodiments are implemented based on the above-described technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments.

[0059] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0060] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0061] Example 1:

[0062] like Figure 1 The system shown is a liquid hydrogen refueling station system with dual liquid hydrogen booster pumps and a thermal management system. It includes a liquid hydrogen tanker truck 1, which connects to a liquid hydrogen storage tank 2 within the station. Liquid hydrogen is supplied to the liquid hydrogen storage tank 2 via a pipeline from the tanker truck. The liquid hydrogen storage tank 2 is connected to a first liquid hydrogen booster pump 3 and a second liquid hydrogen booster pump 4. Each booster pump draws liquid hydrogen from the storage tank and compresses it. The two booster pumps are connected in parallel, each performing its own function without interfering with the other. Simultaneously, the outlet of the first booster pump 3 is connected to a vaporizer 8, which consists of a bare tube vaporizer 81 and a finned tube vaporizer 82. The pressurized, high-pressure, low-temperature liquid hydrogen absorbs heat from the air in the vaporizer 8 to complete the vaporization process. The outlet of the finned tube vaporizer 82 is connected to the high-pressure hydrogen storage mechanism 9 of the liquid hydrogen refueling station, specifically a high-pressure hydrogen storage cylinder group. The outlet of the second booster pump 4 is connected to a temperature equalization tank 13. A parallel pipeline 19 for two liquid hydrogen booster pumps is installed between their output pipelines. A parallel pipeline cryogenic liquid hydrogen control valve 6 on the parallel pipeline 19 controls the flow direction and flow rate of the liquid hydrogen. The heat exchanger 12 fine-tunes the temperature of the hydrogen from the temperature-refilling tank 13 before connecting it to the hydrogen refueling machine 14 to refuel the fuel cell vehicle. The outlet control valve 5 of the first liquid hydrogen booster pump, the parallel pipeline cryogenic liquid hydrogen control valve 6, the outlet control valve 7 of the second liquid hydrogen booster pump, the first liquid hydrogen booster pump 3, the second liquid hydrogen booster pump 4, the vaporizer 8, the heat exchanger 12, and the temperature-refilling tank 13 are all connected to the control system of the entire liquid hydrogen refueling station and are monitored and controlled by the CPU.

[0063] Example 2:

[0064] A hydrogen replenishment method based on the liquid hydrogen refueling station system in Example 1 includes:

[0065] When no vehicles are refueling, the hydrogen refueling machine 14 does not need to operate, meaning the entire liquid hydrogen refueling station has no demand for hydrogen. If the pressure of the hydrogen storage cylinder group in the station has not reached the rated pressure, the entire liquid hydrogen refueling station switches to a gas replenishment strategy. The outlet control valve 7 of the second liquid hydrogen booster pump is closed, while the outlet control valve 5 of the first liquid hydrogen booster pump and the parallel pipeline cryogenic liquid hydrogen control valve 6 are opened. The first liquid hydrogen booster pump 3 and the second liquid hydrogen booster pump 4 simultaneously draw liquid hydrogen from the liquid hydrogen storage tank 2 at a rate of 1 kg / min for pressurization. The pressurized high-pressure liquid hydrogen is input into the vaporizer 8, which consists of a bare tube vaporizer 81 and a finned tube vaporizer 82, for vaporization. The vaporized hydrogen is then introduced into the hydrogen storage cylinder group, where the pressure has not reached the rated pressure. Assuming the volume of a single hydrogen storage cylinder in the hydrogen storage cylinder group is 1 m³, 3 The pressure after hydrogen refueling is 15 MPa. If the liquid hydrogen booster pump needs to supply hydrogen to replenish the pressure of a single hydrogen storage cylinder from 15 MPa to 45 MPa (corresponding to the standard hydrogen storage pressure of a 35 MPa hydrogen refueling station), the density of hydrogen at 298 K and 45 MPa is 28.4524 kg / m³. 3Then the mass of hydrogen in the storage tank at this time is

[0066] m1=ρ*V=28.4524*1=28.4524kg

[0067] The density of hydrogen gas at 298K and 15MPa is 11.1827 kg / m³. 3 Then the mass of hydrogen in the storage tank at this time is

[0068] m2=ρ*V=11.1827*1=11.1827kg

[0069] The required amount of hydrogen is:

[0070] Δm=m1-m2=28.4524-11.1827=17.2697kg

[0071] If only a single liquid hydrogen booster pump is used for gas replenishment at a flow rate of v = 1 kg / min, the required time is

[0072]

[0073] If two liquid hydrogen booster pumps are used simultaneously to replenish the gas at a flow rate of v = 1 kg / min, the required time is...

[0074]

[0075] It can be seen that when two liquid hydrogen booster pumps work simultaneously to replenish the hydrogen storage cylinder group, the required time can be reduced by 50%. The more cylinders in the hydrogen storage cylinder group that have not reached the rated pressure and need to be replenished, the more time is saved by the parallel operation of the two pumps.

[0076] Example 3:

[0077] A hydrogen refueling method based on the liquid hydrogen refueling station system in Example 1 includes:

[0078] When the hydrogen refueling flow rate of the entire liquid hydrogen refueling station at the 70MPa refueling level is less than or equal to 3.36 kg / min, for example, when the hydrogen refueling flow rate is 3.36 kg / min, the parallel pipeline cryogenic liquid hydrogen control valve 6 is closed, and the outlet control valve 5 of the first liquid hydrogen booster pump and the outlet control valve 7 of the second liquid hydrogen booster pump are opened. The first liquid hydrogen booster pump 3 and the second liquid hydrogen booster pump 4 start working simultaneously. The first liquid hydrogen booster pump 3 draws liquid hydrogen from the liquid hydrogen storage tank 2 for pressurization. The pressurized high-pressure liquid hydrogen is input into the vaporizer 8, which is composed of a bare tube vaporizer 81 and a finned tube vaporizer 82, for vaporization. The vaporized gaseous hydrogen is then introduced into the hydrogen storage cylinder (group) whose pressure has not reached the rated pressure. Simultaneously, the second liquid hydrogen booster pump 4 also starts working, drawing liquid hydrogen from the liquid hydrogen storage tank 2 at a flow rate of 1 kg / min for pressurization. The pressurized high-pressure cryogenic liquid hydrogen is then introduced into the temperature equalization tank 13 through the outlet control valve 7 of the second liquid hydrogen booster pump. At the same time, room-temperature hydrogen gas at the same pressure in the high-pressure hydrogen storage cylinder group is introduced into the temperature equalization tank 13 at a flow rate of 2.36 kg / min. The enthalpy of liquid hydrogen at 33 K and 90 MPa is:

[0079] H1 = 970.99 kJ / kg

[0080] The enthalpy of hydrogen at 313.15 K and 45 MPa is:

[0081] H2 = 5260.6 kJ / kg

[0082] The enthalpy of hydrogen after mixing is:

[0083]

[0084] The corresponding hydrogen temperature is -40℃, which meets the pre-cooling temperature requirements for hydrogen refueling. The blended and heated hydrogen is then used to refuel 70MPa vehicles through the 70MPa hydrogen refueling gun of the hydrogen refueling machine 14.

[0085] Example 4:

[0086] A hydrogen refueling method based on the liquid hydrogen refueling station system in Example 1 includes:

[0087] When the hydrogen refueling flow rate of the entire liquid hydrogen refueling station at 35MPa is greater than 3.5kg / min and less than or equal to 7.0kg / min, for example, when the hydrogen refueling flow rate is 7.0kg / min, the outlet control valve 5 of the first liquid hydrogen booster pump is closed, while the parallel pipeline cryogenic liquid hydrogen control valve 6 and the outlet control valve 7 of the second liquid hydrogen booster pump are opened. The first liquid hydrogen booster pump 3 and the second liquid hydrogen booster pump 4 start working simultaneously, drawing liquid hydrogen from the liquid hydrogen storage tank 2 at a flow rate of 1kg / min for pressurization. The high-pressure cryogenic liquid hydrogen pressurized by the first liquid hydrogen booster pump 3 is no longer vaporized through the vaporizer 8 and then passed into the hydrogen storage cylinder group for storage. Instead, it is passed together with the high-pressure cryogenic liquid hydrogen pressurized by the second liquid hydrogen booster pump 4 and then passed into the temperature exchange tank 13 through the outlet control valve 7 of the second liquid hydrogen booster pump. The room-temperature hydrogen gas at the same pressure in the high-pressure hydrogen storage cylinder group is simultaneously passed into the temperature exchange tank 13 at a flow rate of 5kg / min. The enthalpy of liquid hydrogen at 25K and 45MPa is:

[0088] H1 = 490.30 kJ / kg

[0089] The enthalpy of hydrogen at 313.15 K and 45 MPa is:

[0090] H2 = 4923.9 kJ / kg

[0091] The enthalpy of hydrogen after mixing is:

[0092]

[0093] The corresponding hydrogen temperature is -40℃, which meets the pre-cooling temperature requirements for hydrogen refueling. The blended and heated hydrogen is then used to refuel 35MPa vehicles through the 35MPa hydrogen refueling gun of the hydrogen refueling machine 14.

[0094] Example 5:

[0095] A hydrogen refueling method based on the liquid hydrogen refueling station system in Example 1 includes:

[0096] When the hydrogen refueling flow rate at the 70MPa refueling level of the entire liquid hydrogen refueling station exceeds 6.72 kg / min, for example, at 7.2 kg / min, the outlet control valve 5 of the first liquid hydrogen booster pump is closed, while the parallel pipeline cryogenic liquid hydrogen control valve 6 and the outlet control valve 7 of the second liquid hydrogen booster pump are opened. The first liquid hydrogen booster pump 3 and the second liquid hydrogen booster pump 4 start operating simultaneously, drawing liquid hydrogen from the liquid hydrogen storage tank 2 at a flow rate of 1 kg / min for pressurization. The high-pressure cryogenic liquid hydrogen boosted by the first liquid hydrogen booster pump 3 is no longer vaporized by the vaporizer 8 and then passed into the hydrogen storage cylinder group for storage. Instead, it is combined with the high-pressure cryogenic liquid hydrogen boosted by the second liquid hydrogen booster pump 4 and passed through the outlet control valve 7 of the second liquid hydrogen booster pump into the temperature exchange tank 13. Simultaneously, room-temperature hydrogen at the same pressure in the high-pressure hydrogen storage cylinder group is fed into the temperature exchange tank 13 at a flow rate of 5.2 kg / min. The enthalpy of liquid hydrogen at 25K and 90MPa is:

[0097] H1 = 970.99 kJ / kg

[0098] The enthalpy of hydrogen at 313.15 K and 90 MPa is:

[0099] H2 = 5260.6 kJ / kg

[0100] The enthalpy of hydrogen after mixing is:

[0101]

[0102] The corresponding hydrogen temperature is -34.85℃, and the enthalpy value corresponding to -40℃ is 3983.9kJ / kg. The remaining 85.14kJ of cold energy after pre-cooling to -40℃ is provided by heat exchanger 12. After the mixed hydrogen passes through heat exchanger 12, the temperature reaches -40℃, which meets the pre-cooling temperature conditions for hydrogen refueling. The mixed hydrogen is then used to refuel 70MPa vehicles through the 70MPa hydrogen refueling gun of hydrogen refueling machine 14.

[0103] In summary, this invention enables two liquid hydrogen booster pumps to work in coordination, even when the output flow rate of the liquid hydrogen booster pump is currently limited. This allows for rapid refueling of liquid hydrogen at refueling stations. Furthermore, this invention utilizes a combination of high- and low-temperature gas / liquid hydrogen temperature exchange and heat exchanger temperature control to achieve rapid pre-cooling of ambient-temperature hydrogen from the high-pressure hydrogen storage tank. If the cold source is a cold box storing the cold energy released during liquid hydrogen vaporization, the cold energy of the liquid hydrogen can be effectively utilized, saving the significant energy required for additional refrigeration. This reduces the overall energy consumption of the refueling station while fulfilling its system functions, thus contributing to energy conservation and emission reduction.

[0104] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. An operation method based on a liquid hydrogen refueling station system, characterized in that, Liquid hydrogen refueling station system includes The liquid hydrogen source, the second liquid hydrogen booster pump (4), the outlet control valve of the second liquid hydrogen booster pump (7), the temperature mixing tank (13), the heat exchanger (12), and the hydrogen dispenser (14) are connected in series. The liquid hydrogen vaporization pipeline is connected at one end between the liquid hydrogen source and the second liquid hydrogen booster pump (4), and at the other end to the temperature exchange tank (13). A first liquid hydrogen booster pump (3), a first liquid hydrogen booster pump outlet control valve (5), a vaporizer (8), and a hydrogen storage mechanism (9) are connected in series on the liquid hydrogen vaporization pipeline. The vaporizer (8) includes a bare tube vaporizer (81) and a finned tube vaporizer (82) connected in series. A hydrogen pressure sensor and / or a hydrogen temperature sensor are also provided at the outlet of the first liquid hydrogen booster pump (3) and the outlet of the second liquid hydrogen booster pump (4). The hydrogen storage mechanism (9) includes multiple single hydrogen storage cylinders or groups of hydrogen storage cylinders connected in parallel and having different pressure levels. A dual-pump parallel pipeline (19) is connected at both ends to the outlet pipeline of the second liquid hydrogen booster pump (4) and the outlet pipeline of the first liquid hydrogen booster pump (3), respectively. A parallel pipeline cryogenic liquid hydrogen control valve (6) is provided on the dual-pump parallel pipeline (19); and The cold source (11) is connected to the heat exchanger (12) for heat exchange; The operation methods include: Hydrogen replenishment mode: Open the outlet control valve (5) of the first liquid hydrogen booster pump and the parallel pipeline cryogenic liquid hydrogen control valve (6), close the outlet control valve (7) of the second liquid hydrogen booster pump, the second liquid hydrogen booster pump (4) and the first liquid hydrogen booster pump (3) are connected in parallel, and the liquid hydrogen in the liquid hydrogen source is boosted and then fed into the vaporizer (8) for heating and vaporization, and then fed into the hydrogen storage mechanism (9) for storage; First hydrogen addition mode: Open the outlet control valve (5) of the first liquid hydrogen booster pump and the outlet control valve (7) of the second liquid hydrogen booster pump, close the parallel pipeline cryogenic liquid hydrogen control valve (6), the first liquid hydrogen booster pump (3) pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the vaporizer (8) for heating and vaporization, the second liquid hydrogen booster pump (4) pressurizes the liquid hydrogen in the liquid hydrogen source and inputs it into the temperature mixing tank (13), and mixes it with the vaporized hydrogen released by the hydrogen storage mechanism (9) to obtain hydrogen within the set temperature range, and then adds hydrogen to the outside through the hydrogen dispenser (14); Second hydrogen addition mode: Open the parallel pipeline cryogenic liquid hydrogen control valve (6) and the second liquid hydrogen booster pump outlet control valve (7), close the first liquid hydrogen booster pump outlet control valve (5), the second liquid hydrogen booster pump (4) and the first liquid hydrogen booster pump (3) are connected in parallel, and the liquid hydrogen in the liquid hydrogen source is boosted and input into the temperature tank (13), and mixed with the vaporized hydrogen released by the hydrogen storage mechanism (9) to obtain hydrogen within the set temperature range, and then hydrogen is added to the outside through the hydrogen adder (14); Third hydrogen addition mode: Open the parallel pipeline cryogenic liquid hydrogen control valve (6) and the second liquid hydrogen booster pump outlet control valve (7), close the first liquid hydrogen booster pump outlet control valve (5), the second liquid hydrogen booster pump (4) and the first liquid hydrogen booster pump (3) are set in parallel, and the liquid hydrogen in the liquid hydrogen source is boosted and input into the temperature tank (13), and mixed with the vaporized hydrogen released by the hydrogen storage mechanism (9), and then the temperature is adjusted by the heat exchanger (12) to obtain hydrogen within the set temperature range, and then hydrogen is added to the outside through the hydrogen dispenser (14).

2. The operating method according to claim 1, characterized in that, The liquid hydrogen source includes a liquid hydrogen tanker truck (1) and / or a liquid hydrogen storage tank (2).

3. The operating method according to claim 1, characterized in that, Safety relief valves are also provided at the outlet of the first liquid hydrogen booster pump (3) and the outlet of the second liquid hydrogen booster pump (4).

Images