Low-temperature high-pressure hydrogen storage system

Abstract

The application belongs to the technical field of low-temperature hydrogen storage, and discloses a low-temperature high-pressure hydrogen storage system, wherein a low-temperature circulation refrigerating machine comprises a refrigeration compressor, a refrigeration working medium after-cooler, a refrigeration working medium regenerator and a throttling element; an alternating regenerative refrigerating machine comprises a compressor set and a cold head; the compressor set is communicated with the cold head; a hydrogen storage assembly comprises a hydrogen compressor, a hydrogen after-cooler and a high-pressure hydrogen storage container; low-pressure raw hydrogen is pressurized by the hydrogen compressor and then enters the hydrogen after-cooler to be cooled to form high-pressure hydrogen; the high-pressure hydrogen is cooled by the refrigeration working medium regenerator to an optimized temperature in a temperature range of about 80-150K to form intermediate-temperature high-pressure hydrogen; the intermediate-temperature high-pressure hydrogen is cooled by the cold head to an optimized temperature in a temperature range of 34-120K to form low-temperature high-pressure hydrogen which is stored in the high-pressure hydrogen storage container. The low-temperature high-pressure hydrogen storage system disclosed by the application is cooperated by two refrigeration modes to realize good matching of multiple load forms, and to reduce hydrogen storage energy consumption while realizing lower hydrogen storage temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature hydrogen storage, and in particular to a low-temperature and high-pressure hydrogen storage system. Background Art

[0002] Hydrogen, with its high energy density, zero carbon emissions, and widespread availability, is a key secondary energy carrier of the future. However, its low-density gaseous state at room temperature and pressure results in high storage and transportation costs and low efficiency, hindering the large-scale development of the hydrogen energy industry.

[0003] The rise of low-temperature and high-pressure hydrogen storage technology has provided a new path to break through this dilemma. Low-temperature and high-pressure hydrogen storage technology combines the advantages of room-temperature and high-pressure hydrogen storage and low-temperature liquid hydrogen storage. It cools high-pressure hydrogen to a lower temperature through a refrigeration system. While ensuring a higher hydrogen storage density, it has both technical economy and practicality, and has great development potential.

[0004] However, since the physical properties of hydrogen will change significantly under low temperature and high pressure conditions, the mechanisms such as heat conduction and convection heat transfer become more complicated, resulting in complex and varied distribution of multi-form loads within the low-temperature and high-pressure hydrogen storage system, making it difficult for the refrigeration system to well match the multi-form load requirements. Summary of the Invention

[0005] The purpose of the present invention is to provide a low-temperature and high-pressure hydrogen storage system that coordinates two refrigeration methods, can well match multi-form loads, and reduce hydrogen storage energy consumption while achieving lower hydrogen storage temperature.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A low-temperature and high-pressure hydrogen storage system includes a low-temperature cycle refrigerator, an alternating heat recovery refrigerator, and a hydrogen storage component;

[0008] The low-temperature cycle refrigerator includes a refrigeration compressor, a refrigerant aftercooler, a refrigerant heat regenerator and a throttling element. The inlet of the refrigerant aftercooler is connected to the outlet of the refrigeration compressor, and the outlet of the refrigerant aftercooler is connected to the inlet of the refrigerant heat regenerator. The two ends of the throttling element are respectively connected to the outlet of the refrigerant heat regenerator and the inlet of the refrigeration compressor. The mixed working fluid is pressurized by the refrigeration compressor and cooled to room temperature in the refrigerant aftercooler to form a high-pressure mixed working fluid. The high-pressure mixed working fluid enters the refrigerant heat regenerator and is cooled by the low-pressure mixed working fluid. After entering the throttling element, it is throttled and depressurized to form a low-pressure mixed working fluid, and returns to the refrigerant heat regenerator to provide cooling capacity. After reheating, it returns to the refrigeration compressor to complete the cycle.

[0009] The regenerative refrigerator comprises a compressor unit and a cold head, wherein the compressor unit is connected to the cold head and is configured to provide cooling for the cold head;

[0010] The hydrogen storage assembly includes a hydrogen compressor, a hydrogen aftercooler and a high-pressure hydrogen storage container, wherein the hydrogen aftercooler is connected to the outlet of the hydrogen compressor, and the outlet of the hydrogen aftercooler is connected to the high-pressure hydrogen storage container;

[0011] The low-pressure raw hydrogen is pressurized by the hydrogen compressor and then enters the hydrogen aftercooler for cooling to form high-pressure hydrogen. The high-pressure hydrogen is cooled by the refrigerant regenerator to an optimized temperature in the temperature range of about 80 to 150 K to form intermediate-temperature high-pressure hydrogen. The intermediate-temperature high-pressure hydrogen is cooled by the cold head to an optimized temperature in the temperature range of 34 to 120 K to form low-temperature high-pressure hydrogen and stored in the high-pressure hydrogen storage container.

[0012] Preferably, the alternating regenerative refrigerator further includes an extended cold head, which is connected to the cold head and is disposed in the high-pressure hydrogen storage container and adheres to the outer wall of the high-pressure hydrogen storage container.

[0013] Preferably, the low-temperature and high-pressure hydrogen storage system includes multiple alternating regenerative refrigerators connected in series, the low-temperature cycle refrigerator is coupled with the multiple alternating regenerative refrigerators, and the alternating regenerative refrigerator is located between the refrigerant regenerator and the high-pressure hydrogen storage container.

[0014] Preferably, the low-temperature and high-pressure hydrogen storage system includes multiple alternating regenerative refrigerators connected in parallel, the low-temperature cycle refrigerator is coupled to the multiple alternating regenerative refrigerators, and the alternating regenerative refrigerator is located between the refrigerant regenerator and the high-pressure hydrogen storage container, and the cold heads of the multiple alternating regenerative refrigerators respectively cool different streams of intermediate-temperature high-pressure hydrogen.

[0015] Preferably, the low-temperature and high-pressure hydrogen storage system also includes a medium heat exchanger and a medium circuit, and the medium heat exchanger is located between the refrigerant regenerator and the high-pressure hydrogen storage container, the medium heat exchanger is connected to the medium circuit, and a cooling medium flows inside the medium circuit. The cold head is configured to cool the cooling medium in the medium circuit, and a regulating valve is installed in the medium circuit, and the regulating valve is configured to adjust the flow rate of the cooling medium. The cooling medium includes one or more of helium, hydrogen, neon, nitrogen, argon, methane, R14, and propane.

[0016] Preferably, the low-temperature and high-pressure hydrogen storage system also includes a precooling unit, which includes a precooling unit and a precooling heat exchanger. The precooling unit is configured to provide cooling, and the high-pressure mixed working fluid and the high-pressure hydrogen absorb the cooling capacity of the precooling unit in the precooling heat exchanger.

[0017] Preferably, the cold head is connected to the pre-cooling unit to form a loop, and the cold head absorbs the cooling capacity of the pre-cooling unit.

[0018] Preferably, the plurality of regenerative refrigerators are a combination of one or more of a Stirling refrigerator, a GM refrigerator or a pulse tube refrigerator.

[0019] Beneficial effects of the present invention:

[0020] The present invention provides a low-temperature and high-pressure hydrogen storage system, including a low-temperature cycle refrigerator, an alternating heat recovery refrigerator and a hydrogen storage component. The low-temperature cycle refrigerator includes a refrigeration compressor, a refrigerant aftercooler, a refrigerant heat regenerator and a throttling element. The inlet of the refrigerant aftercooler is connected to the outlet of the refrigeration compressor, and the outlet of the refrigerant aftercooler is connected to the inlet of the refrigerant heat regenerator. The two ends of the throttling element are respectively connected to the outlet of the refrigerant heat regenerator and the inlet of the refrigeration compressor. The mixed working fluid is pressurized by the refrigeration compressor and cooled to room temperature in the refrigerant aftercooler to form a high-pressure mixed working fluid. The high-pressure mixed working fluid enters the refrigerant heat regenerator and is cooled by the low-pressure mixed working fluid. After entering the throttling element, it is throttled and depressurized to form a low-pressure mixed working fluid, which returns to the refrigerant heat regenerator to provide cooling capacity. After reheating, it returns to the refrigeration compressor to complete the cycle. The regenerative refrigerator includes a compressor unit and a cold head. The compressor unit is connected to the cold head and is used to provide cooling for the cold head. The hydrogen storage component includes a hydrogen compressor, a hydrogen aftercooler and a high-pressure hydrogen storage container. The hydrogen aftercooler is connected to the outlet of the hydrogen compressor, and the outlet of the hydrogen aftercooler is connected to the high-pressure hydrogen storage container. The low-pressure raw hydrogen is pressurized by the hydrogen compressor and then enters the hydrogen aftercooler for cooling to form high-pressure hydrogen. The high-pressure hydrogen is cooled to an optimized temperature in the temperature range of about 80 to 150K by the refrigerant regenerator to form intermediate-temperature high-pressure hydrogen. The intermediate-temperature high-pressure hydrogen is cooled to an optimized temperature in the temperature range of 34 to 120K by the cold head to form low-temperature high-pressure hydrogen and stored in the high-pressure hydrogen storage container. The present invention coordinates the two refrigeration methods to well match multi-form load requirements and reduce hydrogen storage energy consumption while achieving a lower hydrogen storage temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided in Example 1 of the present invention;

[0022] Figure 2 This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided in Example 2 of the present invention;

[0023] Figure 3 This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided in Example 3 of the present invention;

[0024] Figure 4This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided by the fourth embodiment of the present invention;

[0025] Figure 5 This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided in Example 5 of the present invention;

[0026] Figure 6 This is a structural diagram of a low-temperature and high-pressure hydrogen storage system provided by Example 6 of the present invention;

[0027] Figure 7 This is a structural schematic diagram of a low-temperature and high-pressure hydrogen storage system provided in Example 7 of the present invention.

[0028] In the picture:

[0029] 11. Refrigeration compressor; 12. Refrigerant aftercooler; 13. Refrigerant reheater; 14. Throttling element; 21. Compressor unit; 22. Cold head; 31. Hydrogen compressor; 32. Hydrogen aftercooler; 33. High-pressure hydrogen storage container; 34. High-pressure hydrogen control valve group; 4. Expanded cold head; 51. Medium heat exchanger; 52. Medium circuit; 53. Control valve; 61. Precooling unit; 62. Precooling heat exchanger. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0031] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0032] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0034] Because the physical properties of hydrogen will change significantly under low temperature and high pressure conditions, the mechanisms of heat conduction and convection heat transfer become more complicated, resulting in complex and varied distribution of multi-form loads within the low-temperature and high-pressure hydrogen storage system, making it difficult for the refrigeration system to well match the multi-form load requirements.

[0035] Example 1

[0036] Therefore, this embodiment provides a low-temperature and high-pressure hydrogen storage system, which can well match the multi-form load requirements through the coordinated cooperation of two refrigeration methods, and reduce hydrogen storage energy consumption while achieving a lower hydrogen storage temperature.

[0037] See also Figure 1 A low-temperature and high-pressure hydrogen storage system provided in this embodiment includes a low-temperature refrigeration cycle machine and an alternating heat recovery refrigerator, wherein the low-temperature refrigeration cycle machine performs preliminary cooling treatment on the hydrogen, thereby reducing the hydrogen temperature to an intermediate point, and the alternating heat recovery refrigerator further cools the hydrogen to reduce the hydrogen temperature to a target value, which can well match the multi-form load requirements, and reduce hydrogen storage energy consumption while achieving a lower hydrogen storage temperature.

[0038] Please continue reading Figure 1 The low-temperature cycle refrigerator includes a refrigeration compressor 11, a refrigerant aftercooler 12, a refrigerant heat regenerator 13, and a throttling element 14. Specifically, the inlet of the refrigerant aftercooler 12 is connected to the outlet of the refrigeration compressor 11, and the outlet of the refrigerant aftercooler 12 is connected to the inlet of the refrigerant heat regenerator 13. The two ends of the throttling element 14 are respectively connected to the outlet of the refrigerant heat regenerator 13 and the inlet of the refrigeration compressor 11.

[0039] Through the above arrangement, the mixed working fluid is pressurized by the refrigeration compressor 11 and cooled to room temperature in the refrigerant aftercooler 12 to form a high-pressure mixed working fluid. The high-pressure mixed working fluid enters the refrigerant regenerator 13 and is cooled by the low-pressure mixed working fluid. After entering the throttling element 14, it is throttled and the pressure is reduced to form a low-pressure mixed working fluid. The low-pressure mixed working fluid returns to the refrigerant regenerator 13 to provide cooling capacity, and after being reheated, returns to the refrigeration compressor 11 to complete the cycle.

[0040] Preferably, the refrigerant aftercooler 12 is a condenser, and the condenser is an air-cooled condenser or a water-cooled condenser commonly used in the market.

[0041] Please continue reading Figure 1 The regenerative refrigerator includes a compressor unit 21 and a cold head 22, with the compressor unit 21 connected to the cold head 22. The compressor unit 21 compresses the working gas (usually helium), increasing its pressure. The high-pressure working gas then absorbs heat from the material cooled in the previous cycle, achieving a cooling effect. The high-pressure working gas rapidly expands at the low-temperature end, causing the temperature to drop sharply. The expanded low-temperature working gas absorbs heat from the object being cooled in the cold head 22. In this embodiment, the expanded low-temperature working gas absorbs heat from the hydrogen in the cold head 22.

[0042] Preferably, the regenerative refrigerator may be a Stirling refrigerator, a GM refrigerator, a pulse tube refrigerator or the like.

[0043] The low-temperature, high-pressure hydrogen storage system provided in this embodiment also includes a hydrogen storage component, which is used to provide high-pressure hydrogen to be cooled for the low-temperature cycle refrigerator and the alternating heat recovery refrigerator, and store the low-temperature, high-pressure hydrogen after cooling.

[0044] For details, please refer to Figure 1 The hydrogen storage assembly includes a hydrogen compressor 31, a hydrogen aftercooler 32 and a high-pressure hydrogen storage container 33. The hydrogen aftercooler 32 is connected to the outlet of the hydrogen compressor 31, and the outlet of the hydrogen aftercooler 32 is connected to the high-pressure hydrogen storage container 33.

[0045] Through the above arrangement, the raw hydrogen is pressurized by the hydrogen compressor 31 to obtain high-temperature and high-pressure hydrogen. The high-temperature and high-pressure hydrogen enters the hydrogen aftercooler 32 and is initially cooled to high-pressure hydrogen. When the high-pressure hydrogen passes through the refrigerant regenerator 13, it is further cooled by the low-pressure mixed working medium to an optimized temperature in the temperature range of about 80 to 150K to form intermediate-temperature high-pressure hydrogen. The intermediate-temperature high-pressure hydrogen is further cooled by the cold head 22 to an optimized temperature in the temperature range of 34 to 120K to form low-temperature and high-pressure hydrogen, which is finally stored in the high-pressure hydrogen storage container 33.

[0046] It should be noted that the heat capacity of the high-pressure hydrogen storage container 33 itself and the compression heat generated by the low-temperature high-pressure hydrogen gas being filled into the high-pressure hydrogen storage container 33 can be cooled by the cold head 22 to maintain the target hydrogen storage temperature.

[0047] Preferably, the hydrogen aftercooler 32 is a condenser, and the condenser is an air-cooled condenser or a water-cooled condenser commonly used in the market.

[0048] Furthermore, a high-pressure hydrogen control valve assembly 34 is installed at the opening of the high-pressure hydrogen storage container 33. By controlling the opening and closing of the high-pressure hydrogen control valve assembly 34, low-temperature, high-pressure hydrogen can be filled into the high-pressure hydrogen storage container 33 or discharged from the high-pressure hydrogen storage container 33, thereby improving safety and convenience. It should be noted that the high-pressure hydrogen control valve assembly 34 is a common device that includes multiple control valves, safety valves, and other components, and its structure will not be described in detail here.

[0049] The low-temperature, high-pressure hydrogen storage system provided in this embodiment coordinates two refrigeration methods. The low-temperature refrigeration cycle machine is used to perform preliminary cooling treatment on the hydrogen to reduce the hydrogen temperature to an intermediate point. The alternating heat recovery refrigerator is used to further cool the hydrogen to reduce the hydrogen temperature to a target value. This system can well match the requirements of multi-form loads. At the same time, since the low-temperature refrigeration cycle machine and the alternating heat recovery refrigerator both operate within their most effective temperature ranges, their energy efficiency ratio is improved, thereby achieving a lower hydrogen storage temperature while reducing hydrogen storage energy consumption.

[0050] Example 2

[0051] The low-temperature and high-pressure hydrogen storage system provided in this embodiment is different from that provided in the first embodiment in terms of structure. Figure 2 The alternating heat recovery refrigerator provided in this embodiment also includes an extended cold head 4. Low-temperature and high-pressure hydrogen is filled into the high-pressure hydrogen storage container 33 to generate compression heat. The extended cold head 4 absorbs the above compression heat to cool the high-pressure hydrogen storage container 33, thereby preventing the high-pressure hydrogen storage container 33 from increasing in temperature during the filling process and causing the hydrogen storage density to decrease.

[0052] For details, please refer to Figure 2 The expanded cold head 4 is connected to the cold head 22 through an extension pipe, and the expanded cold head 4 is installed on the outer wall of the high-pressure hydrogen storage container 33. At the same time, the expanded cold head 4 is arranged to fit the outer wall of the high-pressure hydrogen storage container 33 to expand the heat exchange area between the expanded cold head 4 and the high-pressure hydrogen storage container 33.

[0053] The low-temperature, high-pressure hydrogen storage system provided in this embodiment ensures that the temperature of the high-pressure hydrogen storage container 33 is stable during the filling process and reduces the dynamic changes of the multi-modal load by providing an extended cold head 4.

[0054] Example 3

[0055] The low-temperature and high-pressure hydrogen storage system provided in this embodiment is different from that provided in the first embodiment in terms of structure. Figure 3 The alternating regenerative refrigerator provided in this embodiment includes multiple alternating regenerative refrigerators connected in series. The low-temperature cycle refrigerator is coupled with the multiple alternating regenerative refrigerators. The multiple alternating regenerative refrigerators are all located between the refrigerant regenerator 13 and the high-pressure hydrogen storage container 33, and the cold heads 22 of the multiple alternating regenerative refrigerators cool the hydrogen in the cooling pipeline 34 in turn.

[0056] For example, the cold heads 22 of the multiple regenerative refrigerators are in direct contact with the hydrogen to improve heat exchange efficiency.

[0057] In this embodiment, the multiple regenerative refrigerators are a combination of one or more of a Stirling refrigerator, a GM refrigerator, or a pulse tube refrigerator.

[0058] This embodiment further reduces the hydrogen storage temperature by connecting multiple alternating heat recovery refrigerators in series.

[0059] Example 4

[0060] The low-temperature and high-pressure hydrogen storage system provided in this embodiment is different in structure from that provided in the first embodiment. The alternating regenerative refrigerator provided in this embodiment includes multiple alternating regenerative refrigerators connected in parallel. The low-temperature circulating refrigerator is coupled with the multiple alternating regenerative refrigerators. The alternating regenerative refrigerator is located between the refrigerant regenerator 13 and the high-pressure hydrogen storage container 33. For details, please refer to Figure 4 The cold heads 22 of the multiple alternating regenerative refrigerators cool down different streams of hydrogen respectively, and the cooled hydrogen is gathered again and stored in the high-pressure hydrogen storage container 33.

[0061] For example, the cold heads 22 of the multiple regenerative refrigerators are in direct contact with the hydrogen in the cooling pipe 34 to improve heat exchange efficiency.

[0062] In this embodiment, the multiple regenerative refrigerators are a combination of one or more of a Stirling refrigerator, a GM refrigerator, or a pulse tube refrigerator.

[0063] The low-temperature and high-pressure hydrogen storage system provided in this embodiment can, by connecting multiple alternating heat recovery refrigerators in parallel, on the one hand, well match the multi-form load requirements while improving the flexibility of operation, and on the other hand, can also increase the production of low-temperature and high-pressure hydrogen.

[0064] Example 5

[0065] The low-temperature and high-pressure hydrogen storage system provided in this embodiment is different from that provided in the first embodiment in terms of structure. Figure 5The hydrogen storage assembly provided in this embodiment further includes a medium heat exchanger 51 and a medium loop 52 , through which the cold head 22 cools the hydrogen.

[0066] For details, please refer to Figure 5 The medium heat exchanger 51 is located between the refrigerant regenerator 13 and the high-pressure hydrogen storage container 33. The medium heat exchanger 51 is connected to the medium circuit 52, and the cooling medium flows through the medium circuit 52. With this arrangement, the cooling medium in the medium circuit 52 is cooled by the cold head 22 and then enters the medium heat exchanger 51 to cool the hydrogen flowing through the medium heat exchanger 51.

[0067] In this embodiment, by providing the medium heat exchanger 51 and the medium circuit 52 , the cold head 22 will not directly contact the hydrogen, thereby improving the safety of operation.

[0068] Optionally, the cooling medium includes one or more of helium, hydrogen, neon, nitrogen, argon, methane, R14 and propane.

[0069] Preferably, in this embodiment, a regulating valve 53 is further installed in the medium circuit 52. The regulating valve 53 is used to adjust the flow rate of the cooling medium in the medium circuit 52. By adjusting the flow rate of the cooling medium, the cooling temperature of the hydrogen can be flexibly adjusted.

[0070] Example 6

[0071] The low-temperature and high-pressure hydrogen storage system provided in this embodiment is structurally different from that provided in the first embodiment. The hydrogen storage assembly provided in this embodiment also includes a pre-cooling unit, which pre-cools the high-pressure mixed working fluid after being cooled by the refrigerant aftercooler 12 and the high-pressure hydrogen after being cooled by the hydrogen aftercooler 32 to improve the cooling efficiency.

[0072] Specifically, see Figure 6 The precooling unit includes a precooling unit 61 and a precooling heat exchanger 62. The precooling heat exchanger 62 is located between the refrigerant aftercooler 12 and the refrigerant heat regenerator 13. At the same time, the precooling heat exchanger 62 is also located between the hydrogen aftercooler 32 and the refrigerant heat regenerator 13.

[0073] Through the above arrangement, the pre-cooling unit 61 provides cooling capacity, and the high-pressure mixed working fluid cooled by the refrigerant aftercooler 12 absorbs cooling capacity to achieve pre-cooling when passing through the pre-cooling heat exchanger 62. The high-pressure hydrogen gas cooled by the hydrogen aftercooler 32 also absorbs cooling capacity to achieve pre-cooling when passing through the pre-cooling heat exchanger 62, thereby improving the cooling efficiency.

[0074] Optionally, the pre-cooling unit 61 in this embodiment adopts a configuration such as an absorption cycle refrigerator, a vapor compression cycle refrigerator, or a commercial chiller commonly found on the market.

[0075] Example 7

[0076] See also Figure 7 The low-temperature and high-pressure hydrogen storage system provided in this embodiment is further used to pre-cool the cold head 22 in the alternating regenerative refrigerator on the basis of the sixth embodiment to improve the cooling efficiency.

[0077] For details, please refer to Figure 7 The cold head 22 is connected to the pre-cooling unit 61 and forms a loop, and the cold head 22 can absorb the cold energy provided by the pre-cooling unit 61.

[0078] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A low-temperature and high-pressure hydrogen storage system, characterized in that: Including low-temperature cycle refrigerator, alternating heat recovery refrigerator and hydrogen storage components; The low-temperature cycle refrigerator comprises a refrigeration compressor (11), a refrigeration medium aftercooler (12), a refrigeration medium heat exchanger (13) and a throttling element (14). The inlet of the refrigeration medium aftercooler (12) is connected to the outlet of the refrigeration compressor (11), and the outlet of the refrigeration medium aftercooler (12) is connected to the inlet of the refrigeration medium heat exchanger (13). The two ends of the throttling element (14) are respectively connected to the outlet of the refrigeration medium heat exchanger (13) and the inlet of the refrigeration compressor (11). The mixed working medium is pressurized by the refrigeration compressor (11) and cooled to room temperature in the refrigeration medium aftercooler (12) to form a high-pressure mixed working medium. The high-pressure mixed working medium enters the refrigeration medium heat exchanger (13) and is cooled by the low-pressure mixed working medium. After entering the throttling element (14), the pressure is throttled and reduced to form a low-pressure mixed working medium. The mixed working medium returns to the refrigeration medium heat exchanger (13) to provide cooling capacity, and returns to the refrigeration compressor (11) after reheating to complete the cycle. The alternating heat recovery refrigerator comprises a compressor unit (21) and a cold head (22), wherein the compressor unit (21) is connected to the cold head (22), and the compressor unit (21) is configured to provide cooling capacity for the cold head (22); The hydrogen storage assembly comprises a hydrogen compressor (31), a hydrogen aftercooler (32) and a high-pressure hydrogen storage container (33), wherein the hydrogen aftercooler (32) is connected to the outlet of the hydrogen compressor (31), and the outlet of the hydrogen aftercooler (32) is connected to the high-pressure hydrogen storage container (33); The low-temperature and high-pressure hydrogen storage system comprises a plurality of the alternating regenerative refrigerators, the low-temperature circulating refrigerator is coupled to the plurality of the alternating regenerative refrigerators, and the alternating regenerative refrigerators are located between the refrigerant regenerator (13) and the high-pressure hydrogen storage container (33); After being pressurized by the hydrogen compressor (31), the low-pressure raw hydrogen enters the hydrogen aftercooler (32) for cooling to form high-pressure hydrogen. The high-pressure hydrogen is cooled to a temperature within the temperature range of 80-150K by the refrigerant regenerator (13) to form intermediate-temperature high-pressure hydrogen. The intermediate-temperature high-pressure hydrogen is cooled to a temperature within the temperature range of 34-120K by the cold head (22) to form low-temperature high-pressure hydrogen and stored in the high-pressure hydrogen storage container (33). The alternating regenerative refrigerator further comprises an extended cold head (4), the extended cold head (4) being connected to the cold head (22), and the extended cold head (4) being arranged on the high-pressure hydrogen storage container (33) and being attached to the outer wall of the high-pressure hydrogen storage container (33).

2. The low-temperature and high-pressure hydrogen storage system according to claim 1, characterized in that: A plurality of the alternating heat recovery refrigerators are connected in series.

3. The low-temperature and high-pressure hydrogen storage system according to claim 1, characterized in that: A plurality of the alternating heat recovery refrigerators are connected in parallel, and the cold heads (22) of the plurality of the alternating heat recovery refrigerators cool different streams of high-pressure hydrogen at intermediate temperatures respectively.

4. The low-temperature and high-pressure hydrogen storage system according to claim 1, characterized in that: The low-temperature and high-pressure hydrogen storage system further includes a medium heat exchanger (51) and a medium circuit (52). The medium heat exchanger (51) is located between the refrigerant regenerator (13) and the high-pressure hydrogen storage container (33). The medium heat exchanger (51) is connected to the medium circuit (52). A cooling medium circulates inside the medium circuit (52). The cold head (22) is configured to cool the cooling medium in the medium circuit (52). A regulating valve (53) is installed in the medium circuit (52). The regulating valve (53) is configured to regulate the flow of the cooling medium. The cooling medium includes one or more of helium, hydrogen, neon, nitrogen, argon, methane, R14, and propane.

5. The low-temperature and high-pressure hydrogen storage system according to claim 1, characterized in that: The low-temperature and high-pressure hydrogen storage system further includes a precooling unit, which includes a precooling unit (61) and a precooling heat exchanger (62). The precooling unit (61) is configured to provide cooling capacity, and the high-pressure mixed working fluid and high-pressure hydrogen absorb the cooling capacity of the precooling unit in the precooling heat exchanger (62).

6. The low-temperature and high-pressure hydrogen storage system according to claim 5, characterized in that: The cold head (22) is connected to the pre-cooling unit (61) to form a loop, and the cold head (22) absorbs the cold energy of the pre-cooling unit.

7. The low-temperature and high-pressure hydrogen storage system according to claim 2 or 3, characterized in that: The plurality of regenerative refrigerators are a combination of one or more of a Stirling refrigerator, a GM refrigerator, or a pulse tube refrigerator.

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