Energy compensation system for liquid hydrogen gasification station and working method thereof

Abstract

The present application relates to the technical field of energy storage, and discloses a liquid hydrogen hydrogen gasification station energy compensation system and a working method thereof, the liquid hydrogen hydrogen gasification station energy compensation system comprising: a low-pressure liquid hydrogen storage tank and a high-pressure gaseous hydrogen storage tank; a first energy recovery device comprising a low-pressure hydrogen gas chamber, a high-pressure liquid hydrogen chamber and a magnetic refrigeration refrigerator; the low-pressure hydrogen gas chamber is adapted to be connected with the low-pressure liquid hydrogen storage tank to form a liquid hydrogen evaporation gas recovery cycle; a second energy recovery device comprising a high-pressure hydrogen gas chamber, a liquid carbon dioxide chamber and a Stirling machine; the high-pressure liquid hydrogen chamber and the high-pressure hydrogen gas chamber are connected between the low-pressure liquid hydrogen storage tank and the high-pressure gaseous hydrogen storage tank to form a liquid hydrogen vaporization cycle; and a low-temperature heat exchanger adapted to form a liquid carbon dioxide cycle with the liquid carbon dioxide chamber and an external cold load. The present application can not only fully utilize a large amount of low-temperature cold energy, but also reduce the liquid hydrogen loss rate in a long-period storage process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to an energy compensation system of a liquid hydrogen hydrogenation station and a working method thereof. BACKGROUND

[0002] With the gradual increase of new energy installed capacity, the impact of new energy on the power system is becoming increasingly serious. Hydrogen, as a clean secondary energy that can be stored for a long time, plays an increasingly important role in accommodating new energy. However, there is a large spatial and temporal difference between new energy-rich areas and load consumption centers. The mode of sending out new energy through the power system and then producing hydrogen at the load side has great implementation difficulties, and there is a capacity limit in the existing channel. Considering the economy of hydrogen production, there may be a problem of competing for power resources with traditional loads. At the present stage, new energy side hydrogen production is a relatively feasible implementation scheme, and the large-scale sending out of hydrogen energy has become a new constraint factor. Large-scale liquefaction and sending out of hydrogen gas is one of the sending out schemes that have economic and feasibility.

[0003] However, there is an evaporation loss in the storage and transportation of liquid hydrogen, especially in the long-term storage of the user end. At the present stage, the hydrogenation station at the user end is a relatively important application scenario, and the long-term low-temperature preservation of liquid hydrogen and the evaporation and gasification of liquid hydrogen are problems that must be faced and solved. However, there is no comprehensive and targeted technology at the present stage that can comprehensively solve the above problems. The storage temperature of liquid hydrogen needs to be lower than -253℃, and due to the development speed of vehicle hydrogen power system, high-pressure gas hydrogen refueling will have a fixed survival space in the future for a long period of time. The high-pressure gas hydrogen is not lower than -50℃ during the refueling process. In this process, how to fully utilize the cold energy, realize the guarantee of liquid hydrogen low-temperature supply and self-sustaining of station power, is the key point that needs to be researched at the present stage.

[0004] In the prior art, for example, patent literature with publication number CN108386716A discloses that low-temperature gaseous hydrogen generated due to evaporation and gasification (loss of liquid hydrogen) during long-term storage is extracted, heated, and then used for power generation by a fuel cell in the station, but liquid hydrogen is still lost at a rate of 5% per day. Patent literature with publication number CN214119667U discloses that low-temperature gaseous hydrogen generated due to evaporation and gasification (loss of liquid hydrogen) during long-term storage is extracted, then used as a pre-cooling medium for the hydrogenation process to offset the reverse Joule-Thomson effect generated during the hydrogen filling process, and after being pressurized, it is combined with high-pressure hydrogen for filling. This scheme uses cryogenic-level cold energy to pre-cool the target low-temperature filling temperature, and the temperature difference is too large, resulting in excessive energy grade loss, and the safety of the heat exchanger operation is not high. Patent literature with publication number CN113375045A discloses that by setting an intermediate pressure filling process in the system, low-temperature gaseous hydrogen generated due to evaporation and gasification (loss of liquid hydrogen) during long-term storage is extracted, heated, and pressurized to 20 MPa for storage. During the filling process, 20 MPa hydrogen is filled first, and then 45 MPa hydrogen is filled. This scheme has certain improvements compared to the previous scheme, but overall it still cannot effectively control the loss rate of liquid hydrogen.

[0005] Therefore, in the prior art, the existing liquid hydrogen gasification and hydrogen filling station cannot fully utilize a large amount of low-temperature cold energy, and it is difficult to reduce the loss rate of liquid hydrogen during long-term storage. SUMMARY

[0006] In view of this, the present application provides a liquid hydrogen hydrogen gasification station energy compensation system and its working method to solve the problem that the existing liquid hydrogen gasification hydrogen station in the prior art is difficult to fully utilize a large amount of low-temperature cold energy, and is difficult to reduce the liquid hydrogen loss rate in the long-period storage process. The liquid hydrogen hydrogen gasification station energy compensation system mainly comprises a low-pressure liquid hydrogen storage tank, a high-pressure gaseous hydrogen storage tank, a first-stage energy recovery device, a second-stage energy recovery device, a liquid hydrogen collection tank and a low-temperature heat exchanger; wherein the hydrogen gas in the low-pressure liquid hydrogen storage tank is sent into the low-pressure hydrogen gas chamber of the first-stage energy recovery device, is stored in the liquid hydrogen collection tank after being liquefied by magnetic refrigeration, and is then sent back to the low-pressure liquid hydrogen storage tank to complete the liquid hydrogen evaporation gas recovery cycle; the liquid hydrogen in the low-pressure liquid hydrogen storage tank is added to the high-pressure liquid hydrogen chamber of the first-stage energy recovery device, enters the high-pressure hydrogen gas chamber in the second-stage energy recovery device after being heated by excitation therein, is vaporized after passing through the cold end cabin of the Stirling machine and is stored in the high-pressure gaseous hydrogen storage tank to complete the liquid hydrogen vaporization cycle; the liquid carbon dioxide in the liquid carbon dioxide chamber in the second-stage energy recovery device provides cold energy for the cold load, and the excess cold energy is discharged into the atmosphere through the low-temperature heat exchanger to complete the liquid carbon dioxide cycle; the present application increases the first-stage energy recovery device and the second-stage energy recovery device between the low-pressure liquid hydrogen storage tank and the high-pressure hydrogen gas storage tank, thereby realizing deep recovery and utilization of the cold energy in the liquid hydrogen vaporization process, and recovering the hydrogen evaporation gas of the liquid hydrogen hydrogen station. The most easily wasted and most difficult to recover energy in the liquid hydrogen vaporization process is the cold energy recovery in the deep cooling part. The present application recovers the deep cooling energy in the liquid hydrogen vaporization process by two-stage energy recovery of magnetic refrigeration and Stirling, wherein the first-stage energy recovery places the magnetic refrigeration process between the low-pressure liquid hydrogen process and the high-pressure liquid hydrogen process, preheats the high-pressure liquid hydrogen while storing and upgrading the cold energy by using the characteristics of solid refrigeration, and this part of the cold energy can be used for the re-liquefaction of the low-temperature hydrogen gas generated by the evaporation heat absorption in the low-pressure liquid hydrogen to reduce the liquid hydrogen loss rate and the storage time; the second-stage energy recovery places the Stirling power generation cycle between the preheated deep cooling high-pressure liquid hydrogen process and the vaporized low-temperature high-pressure gaseous hydrogen process, utilizes the characteristics of Stirling temperature difference power generation to vaporize the liquid hydrogen and generate electricity at the same time, and the generated electricity is used to drive the required power inside the liquid hydrogen gasification station; after the two-stage energy recovery, the remaining cold energy is stored by using the pressurized carbon dioxide as an energy storage medium, which can be used as a pre-cooling cold source during the conventional high-pressure gaseous hydrogen filling, and can be used as a room temperature section low-temperature cold source supply, and the excess part is discharged.

[0007] In a first aspect, the present application provides a liquid hydrogen hydrogen gasification station energy compensation system, comprising:

[0008] a low-pressure liquid hydrogen storage tank and a high-pressure gaseous hydrogen storage tank;

[0009] a first-stage energy recovery device comprising a low-pressure hydrogen gas chamber, a high-pressure liquid hydrogen chamber and a magnetic refrigeration refrigerator;

[0010] The low-pressure hydrogen chamber is adapted to be connected with the low-pressure liquid hydrogen storage tank to form a liquid hydrogen evaporation gas recycling cycle, and the magnetic refrigeration refrigerator is adapted to release cold energy into the low-pressure hydrogen chamber to liquefy hydrogen gas entering the low-pressure hydrogen chamber from the low-pressure liquid hydrogen storage tank and recycle the hydrogen gas into the low-pressure liquid hydrogen storage tank.

[0011] The secondary energy recycling device comprises a high-pressure hydrogen chamber, a liquid carbon dioxide chamber and a Stirling machine.

[0012] The high-pressure liquid hydrogen chamber and the high-pressure hydrogen chamber are connected between the low-pressure liquid hydrogen storage tank and the high-pressure gaseous hydrogen storage tank to form a liquid hydrogen evaporation cycle, and the magnetic refrigeration refrigerator is adapted to release heat into the high-pressure liquid hydrogen chamber to preheat liquid hydrogen entering the high-pressure liquid hydrogen chamber from the low-pressure liquid hydrogen storage tank; the Stirling machine is adapted to cause the liquid hydrogen in the high-pressure hydrogen chamber to be endothermically vaporized and stored in the high-pressure gaseous hydrogen storage tank.

[0013] The low-temperature heat exchanger is adapted to form a liquid carbon dioxide cycle with the liquid carbon dioxide chamber and an external cold load.

[0014] By arranging the primary energy recycling device between the low-pressure liquid hydrogen storage tank and the high-pressure gaseous hydrogen storage tank, the magnetic refrigeration process is placed between the low-pressure liquid hydrogen process and the high-pressure liquid hydrogen process, the characteristics of solid refrigeration are used to preheat the high-pressure liquid hydrogen, the storage of cold energy is realized at the same time, and the grade is improved, the part of the cold energy can be used for the re-liquefaction of low-temperature hydrogen gas generated by evaporation endotherm in the low-pressure liquid hydrogen, so as to reduce the liquid hydrogen loss rate and the storage time, at the same time, by increasing the primary energy recycling device as the first cold energy recycling during the liquid hydrogen pressurization process, the preheating of the high-pressure low-temperature liquid hydrogen is realized, and the recycled cold energy is used for the liquefaction of hydrogen gas evaporated and endotherm in the low-pressure liquid hydrogen storage tank 1 by the magnetic refrigeration process; by arranging the secondary energy recycling device between the low-pressure liquid hydrogen storage tank and the high-pressure gaseous hydrogen storage tank, the Stirling machine is arranged as the second cold energy recycling during the liquid hydrogen vaporization process, the vaporization of the preheated high-pressure low-temperature liquid hydrogen is realized, and the cold energy is recycled and used for thermoelectric power generation by the Stirling machine, the generated power is used to drive the required power inside the liquid hydrogen gasification station; by the step-by-step use of cold energy during the liquid hydrogen vaporization process, the recycled cold energy at the end can be used for room temperature section refrigeration needs or as a conventional high-pressure gaseous hydrogen pre-cooling cold source, and the excess part is discharged through the air cooling device; in this way, not only a large amount of low-temperature cold energy can be fully utilized, but also the liquid hydrogen loss rate can be reduced during the long-period storage process.

[0015] In an alternative embodiment, the magnetic refrigeration refrigerator comprises a plurality of magnetic rods, the magnetic rods are adapted to reciprocate between the low-pressure hydrogen chamber and the high-pressure liquid hydrogen chamber.

[0016] When the magnetic rod is located in the low-pressure hydrogen chamber, the magnetic rod is adapted to release cold energy into the low-pressure hydrogen chamber to liquefy hydrogen gas stored in the low-pressure hydrogen chamber.

[0017] The magnetic refrigeration refrigerator further comprises a magnetic field area, which is arranged in the high-pressure liquid hydrogen chamber; when the magnetic rod is located in the high-pressure liquid hydrogen chamber, the magnetic rod releases heat to the high-pressure liquid hydrogen chamber under the excitation of the magnetic field area, so as to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber.

[0018] In an alternative embodiment, the magnetic refrigeration refrigerator further comprises:

[0019] The stroke cylinder rod is arranged in the high-pressure liquid hydrogen chamber;

[0020] The threaded rod is connected to the stroke cylinder rod in a screw transmission mode at one end and connected to the magnetic rod at the other end, and is adapted to rotate and move axially relative to the stroke cylinder rod under the drive of the motor, so as to drive the magnetic rod to reciprocate between the low-pressure hydrogen chamber and the high-pressure liquid hydrogen chamber.

[0021] In an alternative embodiment, the magnetic refrigeration refrigerator further comprises a heat exchange sleeve, which is connected to an axial end of the stroke cylinder rod through a head, and is adapted to cover the threaded rod and the magnetic rod to isolate the internal and external of the magnetic refrigeration refrigerator.

[0022] In an alternative embodiment, the Stirling machine comprises:

[0023] The cylinder body is provided with a piston inside;

[0024] The cylinder body is divided into a cold end chamber and a hot end chamber by the piston, the cold end chamber is arranged in the high-pressure hydrogen chamber, the hot end chamber is arranged in the liquid carbon dioxide chamber, and a temperature difference is formed between the cold end chamber and the hot end chamber to drive the piston to move and work and generate electricity.

[0025] In an alternative embodiment, the Stirling machine further comprises:

[0026] The cold end reinforcing fin is arranged on one side of the cylinder body close to the cold end chamber;

[0027] The hot end reinforcing fin is arranged on one side of the cylinder body close to the hot end chamber;

[0028] The cold end reinforcing fin and the hot end reinforcing fin are adapted to respectively reinforce heat transfer in the high-pressure hydrogen chamber and the liquid carbon dioxide chamber to form a temperature difference in the cylinder body to drive the piston to reciprocate, so as to drive the subsequent actuator to work and generate electricity through the piston.

[0029] In an alternative embodiment, the Stirling machine further comprises:

[0030] The fixed shaft;

[0031] The flywheel is coaxially arranged with the fixed shaft;

[0032] The connecting rod is rotatably connected to the piston at one end and rotatably connected to the flywheel at the other end, and is adapted to drive the flywheel to rotate under the drive of the piston.

[0033] In an alternative embodiment, the low-pressure liquid hydrogen storage tank is provided with a liquid hydrogen boil-off gas outlet and a regenerated liquid hydrogen return port; and the low-pressure hydrogen gas chamber is provided with a liquid hydrogen boil-off gas inlet and a regenerated liquid hydrogen outlet;

[0034] The liquid hydrogen boil-off gas inlet is adapted to communicate with the liquid hydrogen boil-off gas outlet, and the regenerated liquid hydrogen outlet is adapted to communicate with the regenerated liquid hydrogen return port, thereby forming a liquid hydrogen boil-off gas recycling cycle.

[0035] In an alternative embodiment, a hydrogen circulation compressor is provided between the liquid hydrogen boil-off gas inlet and the liquid hydrogen boil-off gas outlet, and the hydrogen circulation compressor is adapted to pump the hydrogen gas that has been vaporized and accumulated in the upper portion of the low-pressure liquid hydrogen storage tank into the low-pressure hydrogen gas chamber to overcome the pipeline resistance.

[0036] In an alternative embodiment, a liquid hydrogen collection tank and a liquid hydrogen circulation pump are provided between the regenerated liquid hydrogen outlet and the regenerated liquid hydrogen return port, the liquid hydrogen collection tank is adapted to store the liquefied liquid hydrogen in the low-pressure hydrogen gas chamber, and the liquid hydrogen circulation pump is adapted to pump the liquid hydrogen in the liquid hydrogen collection tank into the low-pressure liquid hydrogen storage tank.

[0037] In an alternative embodiment, the low-pressure liquid hydrogen storage tank comprises a first thermal insulation layer adapted to enclose an inner cavity of the low-pressure liquid hydrogen storage tank;

[0038] The low-pressure hydrogen gas chamber comprises a second thermal insulation layer adapted to enclose an inner cavity of the low-pressure hydrogen gas chamber;

[0039] The high-pressure liquid hydrogen chamber comprises a third thermal insulation layer adapted to enclose an inner cavity of the high-pressure liquid hydrogen chamber;

[0040] The liquid hydrogen collection tank comprises a fourth thermal insulation layer adapted to enclose an inner cavity of the liquid hydrogen collection tank;

[0041] The high-pressure hydrogen gas chamber comprises a fifth thermal insulation layer adapted to enclose an inner cavity of the high-pressure hydrogen gas chamber;

[0042] The liquid carbon dioxide chamber comprises a sixth thermal insulation layer adapted to enclose an inner cavity of the liquid carbon dioxide chamber;

[0043] The high-pressure gaseous hydrogen storage tank comprises a seventh thermal insulation layer adapted to enclose an inner cavity of the high-pressure gaseous hydrogen storage tank.

[0044] By such arrangement, heat exchange between the inside and outside of the low-pressure liquid hydrogen storage tank, the low-pressure hydrogen gas chamber, the high-pressure liquid hydrogen chamber, the liquid hydrogen collection tank, the high-pressure hydrogen gas chamber, the liquid carbon dioxide chamber, and the high-pressure gaseous hydrogen storage tank can be avoided.

[0045] In an alternative embodiment, the low-pressure liquid hydrogen tank is further provided with a liquid hydrogen pressurization outlet; the high-pressure liquid hydrogen chamber is provided with a high-pressure liquid hydrogen preheating inlet and a high-pressure liquid hydrogen preheating outlet; the high-pressure hydrogen gas chamber is provided with a high-pressure hydrogen gasification inlet and a high-pressure hydrogen gasification outlet; and the high-pressure gaseous hydrogen tank is provided with a high-pressure gaseous hydrogen inlet and a high-pressure gaseous hydrogen outlet.

[0046] The high-pressure liquid hydrogen preheating inlet is adapted to communicate with the liquid hydrogen pressurization outlet, the high-pressure liquid hydrogen preheating outlet is adapted to communicate with the high-pressure hydrogen gasification inlet, and the high-pressure hydrogen gasification outlet is adapted to communicate with the high-pressure gaseous hydrogen inlet, thereby forming a liquid hydrogen gasification cycle.

[0047] In an alternative embodiment, a first-stage liquid hydrogen pressurization pump is arranged between the high-pressure liquid hydrogen preheating inlet and the liquid hydrogen pressurization outlet, and is adapted to pressurize the liquid hydrogen from the liquid hydrogen pressurization outlet by one stage and pump it into the high-pressure liquid hydrogen chamber through the high-pressure liquid hydrogen preheating inlet.

[0048] A second-stage liquid hydrogen pressurization pump is arranged between the high-pressure liquid hydrogen preheating outlet and the high-pressure hydrogen gasification inlet, and is adapted to pressurize the liquid hydrogen from the high-pressure liquid hydrogen preheating outlet by two stages and pump it into the high-pressure hydrogen gas chamber through the high-pressure hydrogen gasification inlet.

[0049] In an alternative embodiment, the liquid carbon dioxide chamber is provided with a first liquid carbon dioxide inlet and a first liquid carbon dioxide outlet.

[0050] The low-temperature heat exchanger is provided with a second liquid carbon dioxide inlet and a second liquid carbon dioxide outlet.

[0051] The first liquid carbon dioxide inlet is adapted to communicate with the second liquid carbon dioxide outlet, and the first liquid carbon dioxide outlet is adapted to communicate with the second liquid carbon dioxide inlet, thereby forming a liquid carbon dioxide cycle.

[0052] In an alternative embodiment, a three-way valve is arranged between the first liquid carbon dioxide outlet and the second liquid carbon dioxide inlet, two ports of the three-way valve are respectively connected to the first liquid carbon dioxide outlet and the second liquid carbon dioxide inlet, and the other port is connected to the cold supply port.

[0053] In a second aspect, the present application further provides a working method of the liquid hydrogen hydrogen gasification station energy compensation system as described above, comprising:

[0054] The hydrogen gas vaporized in the low-pressure liquid hydrogen tank is pumped into the low-pressure hydrogen chamber by the hydrogen circulation compressor, the magnetic rod enters the low-pressure hydrogen chamber and releases cold energy, so that the hydrogen stored in the low-pressure hydrogen chamber is liquefied, the pressure in the low-pressure hydrogen chamber is reduced or even negative pressure is generated, and hydrogen is continuously sucked from the low-pressure liquid hydrogen tank, the liquefied liquid hydrogen is discharged into the liquid hydrogen collection tank for storage, and when a sufficient amount is reached, the liquid hydrogen circulation pump is started to pump the liquid hydrogen back to the low-pressure liquid hydrogen tank, completing the liquid hydrogen storage evaporation gas recovery cycle.

[0055] The liquid hydrogen in the low-pressure liquid hydrogen tank is stored in the high-pressure liquid hydrogen chamber after being pressurized by the first-stage liquid hydrogen booster pump, the magnetic rod enters the high-pressure liquid hydrogen chamber and is excited by the magnetic field and releases heat to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber, and the preheated liquid hydrogen is stored in the high-pressure hydrogen chamber after being pressurized by the second-stage liquid hydrogen booster pump, is vaporized by the cold end chamber of the Stirling machine, and is stored in the high-pressure hydrogen tank, completing the liquid hydrogen vaporization cycle.

[0056] The liquid carbon dioxide is stored in the liquid carbon dioxide chamber, and when there is a cold load, the liquid carbon dioxide delivers cold energy to the cold load demand point through the cold supply port, and when the cold load is insufficient to accommodate the cold energy, the low-temperature heat exchanger is started to discharge the cold energy to the atmosphere.

[0057] The method of the application recovers the cryogenic energy of liquid hydrogen vaporization through the two-stage energy recovery of magnetic refrigeration and Stirling, wherein the first-stage energy recovery places the magnetic refrigeration process between the low-pressure liquid hydrogen and high-pressure liquid hydrogen processes, preheats the high-pressure liquid hydrogen using the characteristics of solid refrigeration, stores and upgrades the cold energy, and reduces the liquid hydrogen loss rate and storage time by using the cold energy to re-liquefy the low-temperature hydrogen gas generated by evaporation heat in the low-pressure liquid hydrogen; the second-stage energy recovery places the Stirling power generation cycle between the preheated cryogenic high-pressure liquid hydrogen and the vaporized low-temperature high-pressure hydrogen process, uses the characteristics of Stirling thermoelectric power generation to vaporize liquid hydrogen and generate electricity, and uses the generated electricity to drive the required power inside the liquid hydrogen gasification station; after the two-stage energy recovery, the remaining cold energy is stored as an energy storage medium by using pressurized carbon dioxide, which can be used as a pre-cooling source for regular high-pressure hydrogen filling and as a room temperature low-temperature cold source supply, and the excess part is discharged, which not only fully utilizes a large amount of low-temperature cold energy, but also reduces the liquid hydrogen loss rate during long-term storage.

[0058] In an alternative embodiment, when the pressure in the low-pressure liquid hydrogen tank pipe returns to the normal operating level or slightly lower than the normal pressure, the passage between the low-pressure liquid hydrogen tank and the low-pressure hydrogen chamber is closed.

[0059] In one optional implementation, the operating pressure of the liquid carbon dioxide in the liquid carbon dioxide chamber is P, where P satisfies 7MPa≤P≤10MPa, and the operating temperature is T, where T satisfies -50℃≤T≤-30℃, thereby ensuring that the carbon dioxide will not vaporize. Attached Figure Description

[0060] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0061] Figure 1 This is a schematic diagram illustrating the working principle of an energy compensation system for a liquid hydrogen vaporization station according to an embodiment of the present invention.

[0062] Figure 2 for Figure 1 A schematic diagram illustrating the working principle of a first-stage energy recovery device;

[0063] Figure 3 for Figure 2 A schematic diagram illustrating the working principle of the Zhongci Refrigeration Unit when the magnetic rod is located in the low-pressure hydrogen chamber;

[0064] Figure 4 for Figure 2 A schematic diagram illustrating the working principle of the Zhongci Refrigeration Unit when the magnetic rod is located in the high-pressure liquid hydrogen chamber;

[0065] Figure 5 for Figure 1 Schematic diagram of the working principle of the intermediate-stage energy recovery device;

[0066] Figure 6 for Figure 5 A schematic diagram illustrating the working principle of a Stirling engine.

[0067] Explanation of reference numerals in the attached figures:

[0068] 1. Low-pressure liquid hydrogen storage tank; 10. First insulation layer; 11. Liquid hydrogen evaporation gas outlet; 12. Regenerated liquid hydrogen return port; 13. Liquid hydrogen pressurization outlet; 14. Hydrogen circulation compressor; 15. Liquid hydrogen circulation pump; 16. Liquid hydrogen filling port;

[0069] 2, first energy recovery device; 21, low pressure hydrogen chamber; 210, second adiabatic layer; 211, liquid hydrogen boil-off gas inlet; 212, regenerated liquid hydrogen outlet; 22, high pressure liquid hydrogen chamber; 220, third adiabatic layer; 221, high pressure liquid hydrogen preheat inlet; 222, high pressure liquid hydrogen preheat outlet; 23, magnetic refrigeration refrigerator; 231, magnetic bar; 232, magnetic field region; 233, stroke cylinder rod; 234, threaded rod; 235, heat exchange sleeve; 236, head; 24, first liquid hydrogen booster pump; 25, second liquid hydrogen booster pump;

[0070] 3, liquid hydrogen collection tank; 30, fourth adiabatic layer; 31, collection tank inlet; 32, collection tank outlet;

[0071] 4, second energy recovery device; 41, high pressure hydrogen chamber; 410, fifth adiabatic layer; 411, high pressure hydrogen vaporization inlet; 412, high pressure hydrogen vaporization outlet; 42, liquid carbon dioxide chamber; 420, sixth adiabatic layer; 421, first liquid carbon dioxide inlet; 422, first liquid carbon dioxide outlet; 43, Stirling machine; 431, cylinder; 432, piston; 433, cold end cabin; 434, hot end cabin; 435, cold end reinforcing fin; 436, hot end reinforcing fin; 437, fixed shaft; 438, flywheel; 439, connecting rod;

[0072] 5, high pressure gaseous hydrogen storage tank; 50, seventh adiabatic layer; 51, high pressure gaseous hydrogen inlet; 52, high pressure gaseous hydrogen outlet;

[0073] 6, cryogenic heat exchanger; 61, second liquid carbon dioxide inlet; 62, second liquid carbon dioxide outlet; 63, three-way valve; 64, cold supply port. DETAILED DESCRIPTION

[0074] To solve the problem that the existing liquid hydrogen gasification hydrogen station is difficult to fully utilize a large amount of low-temperature cold energy and difficult to reduce the liquid hydrogen loss rate in the long-period storage process in the prior art, the application provides a liquid hydrogen hydrogen gasification station energy compensation system and a working method thereof, and the liquid hydrogen hydrogen gasification station energy compensation system mainly comprises a low-pressure liquid hydrogen storage tank, a high-pressure gaseous hydrogen storage tank, a first-stage energy recovery device, a second-stage energy recovery device, a liquid hydrogen collecting tank and a low-temperature heat exchanger; wherein the hydrogen in the low-pressure liquid hydrogen storage tank is sent into a low-pressure hydrogen chamber of the first-stage energy recovery device, is stored in the liquid hydrogen collecting tank after being liquefied by magnetic refrigeration, and is then sent back to the low-pressure liquid hydrogen storage tank to complete the liquid hydrogen storage vaporization gas recovery cycle; the liquid hydrogen in the low-pressure liquid hydrogen storage tank is added into a high-pressure liquid hydrogen chamber of the first-stage energy recovery device, enters a high-pressure hydrogen chamber in the second-stage energy recovery device after being heated by excitation, is vaporized after passing through a cold end cabin of a Stirling machine and is stored in the high-pressure gaseous hydrogen storage tank to complete the liquid hydrogen vaporization cycle; the liquid carbon dioxide in the liquid carbon dioxide chamber in the second-stage energy recovery device provides cold energy for the cold load, and the surplus cold energy is discharged into the atmosphere through the low-temperature heat exchanger to complete the liquid carbon dioxide cycle; the application increases the first-stage energy recovery device and the second-stage energy recovery device between the low-pressure liquid hydrogen storage tank and the high-pressure hydrogen storage tank, thereby realizing the deep recovery and utilization of the cold energy in the liquid hydrogen vaporization process and recycling the hydrogen evaporation gas of the liquid hydrogen hydrogen station. The most easily wasted and most difficult to recover energy in the liquid hydrogen vaporization process is the deep cold energy recovery, and the application recovers the deep cold energy in the liquid hydrogen vaporization through the two-stage energy recovery of magnetic refrigeration and Stirling, wherein the first-stage energy recovery places the magnetic refrigeration process between the low-pressure liquid hydrogen process and the high-pressure liquid hydrogen process, preheats the high-pressure liquid hydrogen by using the characteristics of solid refrigeration, stores the cold energy and improves the grade, the cold energy can be used for the re-liquefaction of the low-temperature hydrogen generated by the evaporation heat absorption in the low-pressure liquid hydrogen to reduce the liquid hydrogen loss rate and the storage time, the second-stage energy recovery places the Stirling power generation cycle between the preheated deep cold high-pressure liquid hydrogen process and the vaporized low-temperature high-pressure gaseous hydrogen process, utilizes the characteristics of the Stirling temperature difference power generation to vaporize the liquid hydrogen and generate power at the same time, the generated power is used to drive the required power in the liquid hydrogen gasification station, and the surplus cold energy is stored by using the pressurized carbon dioxide as an energy storage medium, the part of the cold energy can be used as a pre-cooling cold source during the conventional high-pressure gaseous hydrogen filling, and the part of the cold energy can be used as a room temperature section low-temperature cold source supply, and the excess part is discharged.

[0075] To make the purpose, technical scheme and advantages of the embodiments of the application clearer, the technical scheme in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the application.

[0076] Embodiments of the present application will be described below in conjunction with Figures 1 to 6

[0077] According to an embodiment of the present application, in one aspect, there is provided a liquid hydrogen hydrogen gasification station energy compensation system, in particular a liquid hydrogen hydrogen gasification station energy compensation system based on magnetic refrigeration and Stirling power generation, comprising:

[0078] a low-pressure liquid hydrogen storage tank 1 and a high-pressure gaseous hydrogen storage tank 5;

[0079] a primary energy recovery device 2, comprising a low-pressure hydrogen gas chamber 21, a high-pressure liquid hydrogen chamber 22, and a magnetic refrigeration refrigerator 23;

[0080] The low-pressure hydrogen gas chamber 21 is adapted to be connected to the low-pressure liquid hydrogen storage tank 1 to form a liquid hydrogen vaporization gas recovery cycle, and the magnetic refrigeration refrigerator 23 is adapted to release cold energy into the low-pressure hydrogen gas chamber 21, so that the hydrogen gas entering the low-pressure hydrogen gas chamber 21 from the low-pressure liquid hydrogen storage tank 1 is liquefied and recycled back to the low-pressure liquid hydrogen storage tank 1;

[0081] a secondary energy recovery device 4, comprising a high-pressure hydrogen gas chamber 41, a liquid carbon dioxide chamber 42, and a Stirling machine 43;

[0082] The high-pressure liquid hydrogen chamber 22 and the high-pressure hydrogen gas chamber 41 are connected between the low-pressure liquid hydrogen storage tank 1 and the high-pressure gaseous hydrogen storage tank 5 to form a liquid hydrogen vaporization cycle, the magnetic refrigeration refrigerator 23 is adapted to release heat into the high-pressure liquid hydrogen chamber 22, so as to preheat the liquid hydrogen entering the high-pressure liquid hydrogen chamber 22 from the low-pressure liquid hydrogen storage tank 1; the Stirling machine 43 is adapted to cause the liquid hydrogen in the high-pressure hydrogen gas chamber 41 to be endothermically vaporized and stored in the high-pressure gaseous hydrogen storage tank 5;

[0083] a low-temperature heat exchanger 6, the low-temperature heat exchanger 6 is adapted to form a liquid carbon dioxide cycle with the liquid carbon dioxide chamber 42 and an external cold load.

[0084] It should be noted that please refer to Figure 1 and Figure 2 ​As shown, the primary energy recovery device 2 can be composed of one or more same magnetic refrigeration cold box units in parallel, each of which mainly consists of a low-pressure hydrogen chamber 21, a high-pressure liquid hydrogen chamber 22, a magnetic refrigeration refrigerator 23 and a liquid hydrogen collection tank 3, wherein the magnetic refrigeration refrigerator 23 can be a reciprocating magnetic refrigeration refrigerator. In this embodiment, a single magnetic refrigeration cold box unit is taken as an example for illustration. When the whole energy recovery device is started, the hydrogen in the low-pressure hydrogen chamber 21 is extracted by the hydrogen compressor and sent into the low-pressure hydrogen chamber 21 of each magnetic refrigeration cold box unit, at this time the demagnetized magnetic rod 231 is sent into the low-pressure hydrogen chamber 21 through the heat exchange sleeve 235, and the hydrogen is liquefied in the low-pressure hydrogen chamber 21; the liquefied and supercooled liquid hydrogen is collected through the liquid hydrogen collection tank 3 to a certain amount and sent back to the low-pressure liquid hydrogen storage tank 1 through the liquid hydrogen delivery pump; at the same time, the liquid hydrogen in the low-pressure liquid hydrogen storage tank 1 is sent into the high-pressure liquid hydrogen chamber 22 through the liquid hydrogen booster pump for temporary storage, and a strong magnetic field is applied inside the high-pressure liquid hydrogen chamber 22, the magnetic rod 231 is excited when it enters the high-pressure liquid hydrogen chamber 22 through the heat exchange sleeve 235, the temperature of the magnetic rod 231 rises and heats the liquid hydrogen in the high-pressure liquid hydrogen chamber 22, so as to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber 22.

[0085] It should be noted that, please see Figure 1 and Figure 4 As shown, the secondary energy recovery device 4 mainly includes a high-pressure hydrogen chamber 41, a liquid carbon dioxide chamber 42 and a Stirling machine 43, wherein the Stirling machine 43 can be a closed Stirling machine for deep cooling, the liquid carbon dioxide chamber 42 is a low-temperature medium-pressure liquid carbon dioxide chamber, and the cylinder body of the Stirling machine 43 is respectively arranged in the high-pressure hydrogen chamber 41 and the liquid carbon dioxide chamber 42. When the whole energy recovery device is started, due to the temperature difference between the two ends of the cylinder body of the Stirling machine 43, the piston in the cylinder body moves to do work and generate electricity, and the part of the electricity can be used to drive the power equipment in the device and the power consumption in the station, and the heat in the liquid carbon dioxide chamber 42 is pumped into the high-pressure hydrogen chamber 41, so that the deep cooling high-pressure liquid hydrogen injected into the high-pressure hydrogen chamber 41 is vaporized and input into the high-pressure hydrogen storage tank 5 for storage.

[0086] It should be noted that, please see Figure 1 As shown, the liquid hydrogen hydrogenation station energy compensation system of the application is also provided with a low-temperature heat exchanger 6 for removing excess cold or for precooling the cold source before conventional high-pressure hydrogen filling or for supplying the room temperature section low-temperature cold source.

[0087] The energy compensation system of the liquid hydrogen gasification station provided by the embodiment can realize the preheating of high-pressure liquid hydrogen, the storage of cold energy and the upgrading of the grade by setting a first energy recovery device 2 between the low-pressure liquid hydrogen storage tank 1 and the high-pressure hydrogen storage tank 5, placing the magnetic refrigeration process between the low-pressure liquid hydrogen process and the high-pressure liquid hydrogen process, and using the characteristics of solid refrigeration. The cold energy can be used for the re-liquefaction of low-temperature hydrogen gas generated by the evaporation heat absorption in the low-pressure liquid hydrogen, so as to reduce the liquid hydrogen loss rate and the storage time. At the same time, the first energy recovery device 2 is added as the first cold energy recovery during the liquid hydrogen pressurization process, so as to realize the preheating of the high-pressure low-temperature liquid hydrogen, and the recovered cold energy is used for the liquefaction of the hydrogen gas evaporated by heat absorption in the low-pressure liquid hydrogen storage tank 1 through the magnetic refrigeration process. The second energy recovery device 4 is set between the low-pressure liquid hydrogen storage tank 1 and the high-pressure hydrogen storage tank 5, the Stirling machine 43 is added as the second cold energy recovery during the liquid hydrogen gasification process, so as to realize the vaporization of the preheated high-pressure low-temperature liquid hydrogen, and the cold energy is recovered and used for thermoelectric power generation through the Stirling machine. The generated power is used to drive the required power inside the liquid hydrogen gasification station. The cold energy is used in stages during the liquid hydrogen gasification process, the cold energy at the end can be recovered, and if there is a cold load, it can be used for room temperature section refrigeration or as a pre-cooling source before the conventional high-pressure hydrogen filling. The excess part is discharged through the air cooling device. In this way, the low-temperature cold energy can be fully utilized, and the liquid hydrogen loss rate can be reduced during the long-period storage.

[0088] In one embodiment, as shown in Figure 1 and Figure 2 The magnetic refrigeration refrigerator 23 includes a plurality of magnetic rods 231, and the magnetic rods 231 are adapted to reciprocate between the low-pressure hydrogen chamber 21 and the high-pressure liquid hydrogen chamber 22. The magnetic refrigeration refrigerator 23 further includes a magnetic field area 232, and the magnetic field area 232 is arranged in the high-pressure liquid hydrogen chamber 22.

[0089] When the magnetic rod 231 is switched from the high-pressure liquid hydrogen chamber 22 to the low-pressure hydrogen chamber 21, the magnetic rod 231 is demagnetized and cooled, and the magnetic rod 231 releases cold energy into the low-pressure hydrogen chamber 21 to liquefy the hydrogen stored in the low-pressure hydrogen chamber 21.

[0090] When the magnetic rod 231 is located in the high-pressure liquid hydrogen chamber 22, the magnetic rod 231 releases heat into the high-pressure liquid hydrogen chamber 22 under the excitation of the magnetic field area 232, so as to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber 22.

[0091] In one embodiment, as shown in Figure 2 The magnetic refrigeration refrigerator 23 further includes:

[0092] The stroke cylinder rod 233 is arranged in the high-pressure liquid hydrogen chamber 22.

[0093] A threaded rod 234 is connected with the stroke cylinder rod 233 at one end and connected with the magnetic rod 231 at the other end. The threaded rod 234 is adapted to rotate and axially move relative to the stroke cylinder rod 233 under the drive of the motor, so as to drive the magnetic rod 231 to reciprocate between the low-pressure hydrogen chamber 21 and the high-pressure liquid hydrogen chamber 22.

[0094] In one embodiment, referring to Figure 2 The magnetic refrigeration refrigerator 23 further comprises a heat exchange sleeve 235 connected with the axial end of the stroke cylinder rod 233 through a head 236. The heat exchange sleeve 235 is adapted to cover the threaded rod 234 and the magnetic rod 231, so as to isolate the inside of the magnetic refrigeration refrigerator 23 from the outside.

[0095] It should be noted that, referring to Figure 2 The magnetic rod 231 can be directly hot processed into a rod shape from the magnetocaloric material, or the powder is filled into the inner hollow cylinder to form the magnetic rod 231. The magnetic rod 231 can be fixedly integrated at the end of the threaded rod 234. The threaded rod 234 rotates under the drive of the motor and drives the magnetic rod 231 to axially move relative to the stroke cylinder rod 233. Referring to Figure 3 and Figure 4 The stroke range of the threaded rod 234 can be that the threaded rod 234 is just entirely received in the stroke cylinder rod 233 or the threaded rod 234 is just entirely extended out of the stroke cylinder rod 233. The side outer wall of the low-pressure hydrogen chamber 21 abuts against the side outer wall of the high-pressure liquid hydrogen chamber 22, and the magnetic refrigeration refrigerator 23 is simultaneously integrated in the low-pressure hydrogen chamber 21 and the high-pressure liquid hydrogen chamber 22. When the threaded rod 234 reaches the maximum stroke, the magnetic rod 231 can be entirely inserted into the low-pressure hydrogen chamber 21. When the threaded rod 234 is retracted into the stroke cylinder rod 233, the magnetic rod 231 and the stroke cylinder rod 233 are both in the high-pressure liquid hydrogen chamber 22. The magnetic refrigeration refrigerator 23 is cylindrically unitized. A series of cylindrical units can be connected in parallel and integrated in the primary energy recovery device 2 according to the needs. The primary energy recovery device 2 can apply a strong magnetic field to the high-pressure liquid hydrogen chamber 22, and the direction of the magnetic field is perpendicular to all the magnetic rods 231.

[0096] In one embodiment, referring to Figure 5 and Figure 6 The Stirling machine 43 comprises:

[0097] A cylinder body 431, in which a piston 432 is arranged;

[0098] The cylinder body 431 is spaced by the piston 432 to form a cold end cabin 433 and a hot end cabin 434. The cold end cabin 433 is arranged in the high-pressure hydrogen chamber 41, and the hot end cabin 434 is arranged in the liquid carbon dioxide chamber 42. A temperature difference is formed between the cold end cabin 433 and the hot end cabin 434 to drive the piston 432 to move and work and generate electricity.

[0099] In one embodiment, referring to Figure 5 and Figure 6 Stirling machine 43 further comprises:

[0100] Cold end reinforcing fin 435 is arranged on one side of cylinder body 431 close to cold end chamber 433.

[0101] Hot end reinforcing fin 436 is arranged on one side of cylinder body 431 close to hot end chamber 434.

[0102] Cold end reinforcing fin 435 and hot end reinforcing fin 436 are adapted to reinforce heat transfer in high-pressure hydrogen chamber 41 and liquid carbon dioxide chamber 42 respectively to form temperature difference inside cylinder body 431 to drive piston 432 to reciprocate, to drive subsequent actuators to do work and generate electricity.

[0103] It is to be noted that one side outer wall of high-pressure hydrogen chamber 41 abuts against one side outer wall of liquid carbon dioxide chamber 42, and Stirling machine 43 is integrated in high-pressure hydrogen chamber 41 and liquid carbon dioxide chamber 42; wherein cold end chamber 433 is built in high-pressure hydrogen chamber 41, and hot end chamber 434 is built in liquid carbon dioxide chamber 42, cold end chamber 433 and hot end chamber 434 combine to form cylinder body 431 of Stirling machine 43, and cold end reinforcing fin 435 and hot end reinforcing fin 436 reinforce heat transfer in high-pressure hydrogen chamber 41 and liquid carbon dioxide chamber 42 respectively, so as to form temperature difference inside cylinder body 431 to drive piston 432 to reciprocate, to drive subsequent actuators to do work and generate electricity.

[0104] In one embodiment, referring to Figure 5 and Figure 6 Stirling machine 43 further comprises:

[0105] Fixed shaft 437;

[0106] Flywheel 438 is coaxially arranged with fixed shaft 437;

[0107] Connecting rod 439 has one end rotatably connected with piston 432 and the other end rotatably connected with flywheel 438, and connecting rod 439 is adapted to drive flywheel 438 to rotate under the drive of piston 432.

[0108] It is to be noted that in this embodiment, fixed shaft 437, flywheel 438 and connecting rod 439 can form an actuator to do work, and the specific actuator can also be connecting rod cam mechanism or connecting rod mechanism, which can be adjusted according to actual use, and is not limited to the case in this embodiment.

[0109] In one embodiment, referring to Figure 1As shown, the low-pressure liquid hydrogen storage tank 1 is provided with a liquid hydrogen evaporation gas outlet 11 and a regenerated liquid hydrogen return port 12; the low-pressure hydrogen chamber 21 is provided with a liquid hydrogen evaporation gas inlet 211 and a regenerated liquid hydrogen outlet 212.

[0110] The liquid hydrogen evaporation gas inlet 211 is adapted to communicate with the liquid hydrogen evaporation gas outlet 11, and the regenerated liquid hydrogen outlet 212 is adapted to communicate with the regenerated liquid hydrogen return port 12, thereby forming a liquid hydrogen evaporation gas recovery cycle.

[0111] In one embodiment, please refer to Figure 1 As shown, the liquid hydrogen evaporation gas inlet 211 and the liquid hydrogen evaporation gas outlet 11 are provided with a hydrogen circulation compressor 14, which is adapted to overcome the pipeline resistance and pump the hydrogen gas accumulated in the upper part of the low-pressure liquid hydrogen storage tank 1 into the low-pressure hydrogen chamber 21.

[0112] In one embodiment, please refer to Figure 1 As shown, the regenerated liquid hydrogen outlet 212 and the regenerated liquid hydrogen return port 12 are provided with a liquid hydrogen collection tank 3 and a liquid hydrogen circulation pump 15, the liquid hydrogen collection tank 3 is adapted to store the liquefied liquid hydrogen in the low-pressure hydrogen chamber 21, and the liquid hydrogen circulation pump 15 is adapted to pump the liquid hydrogen in the liquid hydrogen collection tank 3 into the low-pressure liquid hydrogen storage tank 1; wherein the liquid hydrogen collection tank 3 is provided with a collection tank inlet 31 and a collection tank outlet 32, the collection tank inlet 31 is adapted to communicate with the regenerated liquid hydrogen outlet 212, and the collection tank outlet 32 is adapted to communicate with the regenerated liquid hydrogen return port 12, and the liquid hydrogen circulation pump 15 is arranged between the collection tank outlet 32 and the regenerated liquid hydrogen return port 12.

[0113] In one embodiment, the low-pressure liquid hydrogen storage tank 1 comprises a first heat insulation layer 10 adapted to form an inner cavity of the low-pressure liquid hydrogen storage tank 1; the low-pressure hydrogen chamber 21 comprises a second heat insulation layer 210 adapted to form an inner cavity of the low-pressure hydrogen chamber 21; the high-pressure liquid hydrogen chamber 22 comprises a third heat insulation layer 220 adapted to form an inner cavity of the high-pressure liquid hydrogen chamber 22; the liquid hydrogen collection tank 3 comprises a fourth heat insulation layer 30 adapted to form an inner cavity of the liquid hydrogen collection tank 3; the high-pressure hydrogen chamber 41 comprises a fifth heat insulation layer 410 adapted to form an inner cavity of the high-pressure hydrogen chamber 41; the liquid carbon dioxide chamber 42 comprises a sixth heat insulation layer 420 adapted to form an inner cavity of the liquid carbon dioxide chamber 42; and the high-pressure gaseous hydrogen storage tank 5 comprises a seventh heat insulation layer 50 adapted to form an inner cavity of the high-pressure gaseous hydrogen storage tank 5, thereby avoiding heat exchange between the inside and outside of the low-pressure liquid hydrogen storage tank 1, the low-pressure hydrogen chamber 21, the high-pressure liquid hydrogen chamber 22, the liquid hydrogen collection tank 3, the high-pressure hydrogen chamber 41, the liquid carbon dioxide chamber 42, and the high-pressure gaseous hydrogen storage tank 5.

[0114] In one embodiment, please refer to Figure 1 As shown in the figure, the low-pressure liquid hydrogen storage tank 1 is also provided with a liquid hydrogen pressurization outlet 13; the high-pressure liquid hydrogen chamber 22 is provided with a high-pressure liquid hydrogen preheating inlet 221 and a high-pressure liquid hydrogen preheating outlet 222; the high-pressure hydrogen gas chamber 41 is provided with a high-pressure hydrogen gasification inlet 411 and a high-pressure hydrogen gasification outlet 412; the high-pressure gaseous hydrogen storage tank 5 is provided with a high-pressure gaseous hydrogen inlet 51 and a high-pressure gaseous hydrogen outlet 52.

[0115] The high-pressure liquid hydrogen preheating inlet 221 is adapted to communicate with the liquid hydrogen pressurization outlet 13, the high-pressure liquid hydrogen preheating outlet 222 is adapted to communicate with the high-pressure hydrogen gasification inlet 411, and the high-pressure hydrogen gasification outlet 412 is adapted to communicate with the high-pressure gaseous hydrogen inlet 51, thereby forming a liquid hydrogen gasification cycle.

[0116] Optionally, the low-pressure liquid hydrogen storage tank 1 is also provided with a liquid hydrogen filling inlet 16.

[0117] In one embodiment, please refer to Figure 1 As shown in the figure, a first-stage liquid hydrogen pressurization pump 24 is arranged between the high-pressure liquid hydrogen preheating inlet 221 and the liquid hydrogen pressurization outlet 13, and the first-stage liquid hydrogen pressurization pump 24 is adapted to perform first-stage pressurization on the liquid hydrogen from the liquid hydrogen pressurization outlet 13 and pump it into the high-pressure liquid hydrogen chamber 22 through the high-pressure liquid hydrogen preheating inlet 221.

[0118] A second-stage liquid hydrogen pressurization pump 25 is arranged between the high-pressure liquid hydrogen preheating outlet 222 and the high-pressure hydrogen gasification inlet 411, and the second-stage liquid hydrogen pressurization pump 25 is adapted to perform second-stage pressurization on the liquid hydrogen from the high-pressure liquid hydrogen preheating outlet 222 and pump it into the high-pressure hydrogen gas chamber 41 through the high-pressure hydrogen gasification inlet 411.

[0119] In one embodiment, please refer to Figure 1 As shown in the figure, the liquid carbon dioxide chamber 42 is provided with a first liquid carbon dioxide inlet 421 and a first liquid carbon dioxide outlet 422;

[0120] The low-temperature heat exchanger 6 is provided with a second liquid carbon dioxide inlet 61 and a second liquid carbon dioxide outlet 62;

[0121] The first liquid carbon dioxide inlet 421 is adapted to communicate with the second liquid carbon dioxide outlet 62, and the first liquid carbon dioxide outlet 422 is adapted to communicate with the second liquid carbon dioxide inlet 61, thereby forming a liquid carbon dioxide cycle.

[0122] In one embodiment, please refer to Figure 1 Figure 1 As shown in the figure, a three-way valve 63 is arranged between the first liquid carbon dioxide outlet 422 and the second liquid carbon dioxide inlet 61, two ports of the three-way valve 63 are connected with the first liquid carbon dioxide outlet 422 and the second liquid carbon dioxide inlet 61 respectively, and the other port is connected with a cold supply port 64.

[0123] According to an embodiment of the present application, in another aspect, there is also provided a method for operating a liquid hydrogen gasification station energy compensation system as described above, comprising:

[0124] The hydrogen gas accumulated on the upper part of the low-pressure liquid hydrogen storage tank 1 is discharged through the liquid hydrogen evaporation gas outlet 11 and pumped into the low-pressure hydrogen chamber 21 by overcoming the pipeline resistance through the hydrogen circulation compressor 14; when the device needs to be started, the control magnet bar 231 enters the low-pressure hydrogen chamber 21, and since there is no magnetic field in the low-pressure hydrogen chamber 21, the demagnetized magnet bar 231 starts to release cold energy into the low-pressure hydrogen chamber 21, so that the hydrogen stored in the low-pressure hydrogen chamber 21 is liquefied, the pressure in the low-pressure hydrogen chamber 21 is reduced or even negative pressure is generated, and hydrogen is continuously sucked from the low-pressure liquid hydrogen storage tank 1, and the liquefied liquid hydrogen is discharged into the liquid hydrogen collection tank 3 for storage; when a sufficient amount is reached, the liquid hydrogen circulation pump 15 is started to pump the liquid hydrogen back to the low-pressure liquid hydrogen storage tank 1, completing the liquid hydrogen evaporation gas recovery cycle; wherein the pressures in the low-pressure liquid hydrogen storage tank 1, the low-pressure hydrogen chamber 21 and the liquid hydrogen collection tank 3 can be operated within the temperature range of 20K and the pressure range of normal pressure, and the system does not appear negative pressure state continuously for a long period during operation.

[0125] The liquid hydrogen in the low-pressure liquid hydrogen storage tank 1 is lifted to 10MPa after being pressurized by the first-stage liquid hydrogen booster pump 24, and the temperature is raised to about 40K and stored in the high-pressure liquid hydrogen chamber 22; the magnet bar 231 enters the magnetic field area of the high-pressure liquid hydrogen chamber 22 and is excited by the magnetic field and releases heat to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber 22; the temperature of the liquid hydrogen after being pressurized by the first-stage booster pump can be raised to 40K-50K after preheating in the high-pressure liquid hydrogen chamber 22; the preheated liquid hydrogen is pressurized by the second-stage liquid hydrogen booster pump 25 to 80MPa, the temperature is raised to about 70K, and is stored in the high-pressure hydrogen chamber 41; the hydrogen gas is vaporized by absorbing heat in the cold end cabin 433 of the Stirling machine 43 in the high-pressure hydrogen chamber 41, at this time the hydrogen gas is raised to 90MPa and the temperature is raised to 200K and stored in the high-pressure hydrogen storage tank 5, thereby providing a pre-cooled hydrogen source for the hydrogen filling machine, and thus completing the liquid hydrogen vaporization cycle.

[0126] The liquid carbon dioxide is mainly stored in the liquid carbon dioxide chamber 42, and the liquid carbon dioxide is mainly used as a cooling medium; when there is a cold load, the liquid carbon dioxide delivers cold energy to the cold load demand point through the cold supply port 64; when the cold load is insufficient to absorb the cold energy, the low-temperature heat exchanger 6 is started to discharge the cold energy to the atmosphere.

[0127] It should be noted that according to statistics, since the deep cryogenic low-pressure liquid hydrogen storage tank is basically a constant-pressure container, the daily liquid hydrogen loss of the deep cryogenic low-pressure liquid hydrogen storage tank is more than 5%, and the vaporization process makes the pressure in the deep cryogenic low-pressure liquid hydrogen storage tank increase, which increases the storage safety hazard, so regenerating the part of the vaporized liquid hydrogen is the need of the economy of long-period storage of liquid hydrogen and the need of safe storage. The energy that is most easily wasted and most difficult to recover in the liquid hydrogen vaporization process is mainly the recovery of the cold energy of the deep cryogenic part. The method of the present application recovers the deep cryogenic energy of the liquid hydrogen vaporization through the dual-stage energy recovery of magnetic refrigeration and Stirling; wherein the first-stage energy recovery places the magnetic refrigeration process between the low-pressure liquid hydrogen process and the high-pressure liquid hydrogen process, preheats the high-pressure liquid hydrogen while realizing the storage and upgrading of the cold energy by using the characteristics of solid refrigeration, and this part of the cold energy can be used for the re-liquefaction of the low-temperature hydrogen gas generated by the evaporation heat in the low-pressure liquid hydrogen, so as to reduce the liquid hydrogen loss rate and the storage time; the second-stage energy recovery places the Stirling power generation cycle between the preheated deep cryogenic high-pressure liquid hydrogen process and the vaporized low-temperature high-pressure hydrogen process, utilizes the characteristics of Stirling temperature difference power generation, on the one hand vaporizes the liquid hydrogen, and on the other hand generates power, and the generated power is used to drive the required power inside the liquid hydrogen gasification station; after the two-stage energy recovery, the remaining cold energy is stored by using the pressurized carbon dioxide as an energy storage medium, on the one hand, this part of the cold energy can be used as a pre-cooling cold source during the filling of conventional high-pressure hydrogen, and on the other hand, this part of the cold energy can be used as a room-temperature low-temperature cold source supply, and the excess part is discharged, which not only can fully utilize a large amount of low-temperature cold energy, but also can reduce the liquid hydrogen loss rate during long-period storage.

[0128] In one embodiment, the passage between the low-pressure liquid hydrogen storage tank 1 and the low-pressure hydrogen chamber 21 is closed when the in-tube pressure of the low-pressure liquid hydrogen storage tank 1 recovers to the normal operating level or slightly lower than the normal pressure.

[0129] In one embodiment, the operating pressure of the liquid carbon dioxide in the liquid carbon dioxide chamber 42 is P, P satisfies 7MPa≤P≤10MPa, and the operating temperature is T, T satisfies -50℃≤T≤-30℃, so as to ensure that the carbon dioxide does not vaporize.

[0130] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A liquid hydrogen gasification station energy compensation system, characterized by, The application relates to a hydrogen energy storage system, which comprises: a low-pressure liquid hydrogen storage tank (1) and a high-pressure gaseous hydrogen storage tank (5); a primary energy recovery device (2) comprising a low-pressure hydrogen chamber (21), a high-pressure liquid hydrogen chamber (22) and a magnetic refrigeration refrigerator (23); the low-pressure hydrogen chamber (21) is adapted to be connected with the low-pressure liquid hydrogen storage tank (1) to form a liquid hydrogen evaporation gas recovery cycle, and the magnetic refrigeration refrigerator (23) is adapted to release cold energy into the low-pressure hydrogen chamber (21) to liquefy hydrogen gas entering the low-pressure hydrogen chamber (21) from the low-pressure liquid hydrogen storage tank (1) and recycle the hydrogen gas into the low-pressure liquid hydrogen storage tank (1); a secondary energy recovery device (4) comprising a high-pressure hydrogen chamber (41), a liquid carbon dioxide chamber (42) and a Stirling machine (43); the high-pressure liquid hydrogen chamber (22) and the high-pressure hydrogen chamber (41) are connected between the low-pressure liquid hydrogen storage tank (1) and the high-pressure gaseous hydrogen storage tank (5) to form a liquid hydrogen vaporization cycle, the magnetic refrigeration refrigerator (23) is adapted to release heat into the high-pressure liquid hydrogen chamber (22) to preheat liquid hydrogen entering the high-pressure liquid hydrogen chamber (22) from the low-pressure liquid hydrogen storage tank (1), and the Stirling machine (43) is adapted to make liquid hydrogen in the high-pressure hydrogen chamber (41) absorb heat to vaporize and be stored in the high-pressure gaseous hydrogen storage tank (5); a low-temperature heat exchanger (6) adapted to form a liquid carbon dioxide cycle with the liquid carbon dioxide chamber (42) and external cold load; the magnetic refrigeration refrigerator (23) comprises a plurality of magnetic rods (231) adapted to reciprocate between the low-pressure hydrogen chamber (21) and the high-pressure liquid hydrogen chamber (22); when the magnetic rod (231) is located in the low-pressure hydrogen chamber (21), the magnetic rod (231) is adapted to release cold energy into the low-pressure hydrogen chamber (21) to liquefy hydrogen stored in the low-pressure hydrogen chamber (21); the magnetic refrigeration refrigerator (23) further comprises a magnetic field area (232) arranged in the high-pressure liquid hydrogen chamber (22), and when the magnetic rod (231) is located in the high-pressure liquid hydrogen chamber (22), the magnetic rod (231) releases heat into the high-pressure liquid hydrogen chamber (22) under the excitation of the magnetic field area (232) to preheat liquid hydrogen in the high-pressure liquid hydrogen chamber (22).

2. The liquid hydrogen gasification station energy compensation system of claim 1, wherein, the magnetic refrigeration refrigerator (23) further comprises: a stroke cylinder rod (233) arranged in the high-pressure liquid hydrogen chamber (22); a threaded rod (234) having one end in screw transmission connection with the stroke cylinder rod (233) and the other end connected with the magnetic rod (231), the threaded rod (234) is adapted to rotate under the drive of a motor and axially move relative to the stroke cylinder rod (233) to drive the magnetic rod (231) to reciprocate between the low-pressure hydrogen chamber (21) and the high-pressure liquid hydrogen chamber (22).

3. The liquid hydrogen gasification station energy compensation system of claim 2, wherein, The magnetic refrigeration refrigerator (23) further comprises a heat exchange sleeve (235) connected to an axial end of the stroke cylinder rod (233) through a head (236), and the heat exchange sleeve (235) is suitable for covering the threaded rod (234) and the magnetic bar (231) to isolate the exchange of matter between the inside and outside of the magnetic refrigeration refrigerator (23).

4. The liquid hydrogen gasification station energy compensation system of claim 1, wherein, The Stirling machine (43) comprises: a cylinder (431) in which a piston (432) is arranged; the cylinder (431) is spaced by the piston (432) to form a cold end chamber (433) and a hot end chamber (434), the cold end chamber (433) is arranged in the high-pressure hydrogen chamber (41), the hot end chamber (434) is arranged in the liquid carbon dioxide chamber (42), and a temperature difference is formed between the cold end chamber (433) and the hot end chamber (434) to drive the piston (432) to move and work to generate electricity.

5. The liquid hydrogen gasification station energy compensation system of claim 4, wherein, The Stirling machine (43) further comprises: a cold end reinforcing fin (435) arranged on one side of the cylinder (431) close to the cold end chamber (433); a hot end reinforcing fin (436) arranged on one side of the cylinder (431) close to the hot end chamber (434); the cold end reinforcing fin (435) and the hot end reinforcing fin (436) are suitable for reinforcing heat transfer in the high-pressure hydrogen chamber (41) and the liquid carbon dioxide chamber (42) respectively to form a temperature difference in the cylinder (431) to drive the piston (432) to reciprocate, so that the subsequent actuator is driven by the piston (432) to work and generate electricity.

6. The liquid hydrogen gasification station energy compensation system of claim 4, wherein, The Stirling machine (43) further comprises: a fixed shaft (437); a flywheel (438) coaxially arranged with the fixed shaft (437); a connecting rod (439) having one end rotatably connected with the piston (432) and the other end rotatably connected with the flywheel (438), and the connecting rod (439) is suitable for driving the flywheel (438) to rotate under the drive of the piston (432).

7. The liquid hydrogen gasification plant energy compensation system of any of claims 1-6, wherein, The low-pressure hydrogen chamber (21) is provided with a liquid hydrogen evaporation gas inlet (211) and a regenerated liquid hydrogen outlet (212), and the low-pressure liquid hydrogen storage tank (1) is provided with a liquid hydrogen evaporation gas outlet (11) and a regenerated liquid hydrogen return port (12); the liquid hydrogen evaporation gas inlet (211) is suitable for being in communication with the liquid hydrogen evaporation gas outlet (11), and the regenerated liquid hydrogen outlet (212) is suitable for being in communication with the regenerated liquid hydrogen return port (12).

8. The liquid hydrogen gasification station energy compensation system of claim 7, wherein, A hydrogen circulation compressor (14) is arranged between the liquid hydrogen evaporation gas inlet (211) and the liquid hydrogen evaporation gas outlet (11), and the hydrogen circulation compressor (14) is suitable for overcoming the pipeline resistance to pump the hydrogen gas accumulated in the upper part of the low-pressure liquid hydrogen storage tank (1) into the low-pressure hydrogen chamber (21) through the liquid hydrogen evaporation gas inlet (211).

9. The liquid hydrogen gasification station energy compensation system of claim 8, wherein, A liquid hydrogen collecting tank (3) is arranged between the regenerative liquid hydrogen outlet (212) and the regenerative liquid hydrogen return port (12), and is adapted to store the liquefied liquid hydrogen in the low-pressure hydrogen chamber (21); and a liquid hydrogen circulating pump (15) is arranged between the liquid hydrogen collecting tank (3) and the low-pressure liquid hydrogen storage tank (1), and is adapted to pump the liquid hydrogen in the liquid hydrogen collecting tank (3) into the low-pressure liquid hydrogen storage tank (1).

10. The liquid hydrogen gasification station energy compensation system of claim 9, wherein, The low-pressure liquid hydrogen storage tank (1) comprises a first heat insulation layer (10) adapted to enclose an inner cavity of the low-pressure liquid hydrogen storage tank (1); The low-pressure hydrogen chamber (21) comprises a second heat insulation layer (210) adapted to enclose an inner cavity of the low-pressure hydrogen chamber (21); The high-pressure liquid hydrogen chamber (22) comprises a third heat insulation layer (220) adapted to enclose an inner cavity of the high-pressure liquid hydrogen chamber (22); The liquid hydrogen collecting tank (3) comprises a fourth heat insulation layer (30) adapted to enclose an inner cavity of the liquid hydrogen collecting tank (3); The high-pressure hydrogen chamber (41) comprises a fifth heat insulation layer (410) adapted to enclose an inner cavity of the high-pressure hydrogen chamber (41); The liquid carbon dioxide chamber (42) comprises a sixth heat insulation layer (420) adapted to enclose an inner cavity of the liquid carbon dioxide chamber (42); The high-pressure gaseous hydrogen storage tank (5) comprises a seventh heat insulation layer (50) adapted to enclose an inner cavity of the high-pressure gaseous hydrogen storage tank (5).

11. The liquid hydrogen gasification plant energy compensation system of any of claims 1-6, wherein, The low-pressure liquid hydrogen storage tank (1) is further provided with a liquid hydrogen pressurizing outlet (13); the high-pressure liquid hydrogen chamber (22) is provided with a high-pressure liquid hydrogen preheating inlet (221) and a high-pressure liquid hydrogen preheating outlet (222); the high-pressure hydrogen chamber (41) is provided with a high-pressure hydrogen vaporizing inlet (411) and a high-pressure hydrogen vaporizing outlet (412); and the high-pressure gaseous hydrogen storage tank (5) is provided with a high-pressure gaseous hydrogen inlet (51) and a high-pressure gaseous hydrogen outlet (52). The high-pressure liquid hydrogen preheating inlet (221) is adapted to be in communication with the liquid hydrogen pressurizing outlet (13), the high-pressure liquid hydrogen preheating outlet (222) is adapted to be in communication with the high-pressure hydrogen vaporizing inlet (411), and the high-pressure hydrogen vaporizing outlet (412) is adapted to be in communication with the high-pressure gaseous hydrogen inlet (51).

12. The liquid hydrogen gasification station energy compensation system of claim 11, wherein, A first-stage liquid hydrogen pressurizing pump (24) is arranged between the high-pressure liquid hydrogen preheating inlet (221) and the liquid hydrogen pressurizing outlet (13), and is adapted to pressurize the liquid hydrogen from the liquid hydrogen pressurizing outlet (13) by one stage and pump the liquid hydrogen into the high-pressure liquid hydrogen chamber (22) through the high-pressure liquid hydrogen preheating inlet (221); A two-stage liquid hydrogen booster pump (25) is arranged between the high-pressure liquid hydrogen preheating outlet (222) and the high-pressure hydrogen vaporization inlet (411), and is adapted to perform two-stage boosting on the liquid hydrogen from the high-pressure liquid hydrogen preheating outlet (222) and pump the liquid hydrogen into the high-pressure hydrogen gas chamber (41) through the high-pressure hydrogen vaporization inlet (411).

13. The liquid hydrogen gasification plant energy compensation system of any of claims 1-6, wherein, The liquid carbon dioxide chamber (42) is provided with a first liquid carbon dioxide inlet (421) and a first liquid carbon dioxide outlet (422); The low-temperature heat exchanger (6) is provided with a second liquid carbon dioxide inlet (61) and a second liquid carbon dioxide outlet (62); The first liquid carbon dioxide inlet (421) is adapted to communicate with the second liquid carbon dioxide outlet (62), and the first liquid carbon dioxide outlet (422) is adapted to communicate with the second liquid carbon dioxide inlet (61).

14. The liquid hydrogen gasification station energy compensation system of claim 13, wherein, A three-way valve (63) is arranged between the first liquid carbon dioxide outlet (422) and the second liquid carbon dioxide inlet (61), two ports of the three-way valve (63) are connected with the first liquid carbon dioxide outlet (422) and the second liquid carbon dioxide inlet (61) respectively, and the other port is connected with a cold supply port (64).

15. A method of operating an energy compensation system of a liquid hydrogen hydrogenation station according to any one of the preceding claims 1-14, characterized in that, Comprise: The hydrogen gas vaporized in the low-pressure liquid hydrogen storage tank (1) is pumped into the low-pressure hydrogen gas chamber (21) through the hydrogen circulation compressor (14), the magnetic bar (231) enters the low-pressure hydrogen gas chamber (21) and releases cold energy, so that the hydrogen gas stored in the low-pressure hydrogen gas chamber (21) is liquefied, the pressure in the low-pressure hydrogen gas chamber (21) is reduced or even negative pressure is generated, and hydrogen gas is continuously sucked from the low-pressure liquid hydrogen storage tank (1), the liquefied liquid hydrogen is discharged into the liquid hydrogen collection tank (3) for storage, and when a sufficient amount is reached, the liquid hydrogen circulation pump (15) is started to pump the liquid hydrogen back to the low-pressure liquid hydrogen storage tank (1), completing the liquid hydrogen storage gas evaporation recovery cycle; The liquid hydrogen in the low-pressure liquid hydrogen storage tank (1) is stored in the high-pressure liquid hydrogen chamber (22) after being one-stage boosted by the first-stage liquid hydrogen booster pump (24), the magnetic bar (231) enters the high-pressure liquid hydrogen chamber (22) and is excited by the magnetic field and releases heat to preheat the liquid hydrogen in the high-pressure liquid hydrogen chamber (22), the preheated liquid hydrogen is stored in the high-pressure hydrogen gas chamber (41) after being two-stage boosted by the second-stage liquid hydrogen booster pump (25), is vaporized by absorbing heat through the cold end cabin (433) of the Stirling machine (43), and is stored in the high-pressure hydrogen gas storage tank (5), completing the liquid hydrogen vaporization cycle; The liquid carbon dioxide is stored in the liquid carbon dioxide chamber (42), and when there is a cold load, the liquid carbon dioxide delivers cold energy to the cold load demand point through the cold supply port (64), and when the cold load is insufficient to accommodate the cold energy, the low-temperature heat exchanger (6) is started to discharge the cold energy to the atmosphere.

16. The method of claim 15, wherein, When the pressure in the low-pressure liquid hydrogen storage tank (1) returns to the normal operating level or is slightly lower than the normal pressure, the passage between the low-pressure liquid hydrogen storage tank (1) and the low-pressure hydrogen gas chamber (21) is closed.

17. The method of claim 16, wherein the liquid hydrogen gasification station energy compensation system is further characterized by, The liquid carbon dioxide operates in the liquid carbon dioxide chamber (42) at a pressure P, which satisfies 7 MPa≤P≤10 MPa, and at a temperature T, which satisfies -50℃≤T≤-30℃.

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