Liquid hydrogen pressurization device

Abstract

The application relates to a liquid hydrogen pressurizing device, which comprises a liquid hydrogen pressurizing pump and a refrigerator for cooling the liquid hydrogen pressurizing pump. The precooling of the liquid hydrogen pressurizing pump by the refrigerator can achieve the purpose of low heat leakage or zero evaporation of the liquid hydrogen pressurizing pump. Compared with the prior art, the liquid hydrogen pressurizing device effectively reduces or eliminates the evaporation amount of liquid hydrogen in the liquid pool of the liquid hydrogen pressurizing pump when the liquid hydrogen pressurizing pump stops, and is an important guarantee for realizing zero evaporation of a liquid hydrogen hydrogenation station system.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of liquid hydrogen pressurization and relates to a liquid hydrogen pressurization device. BACKGROUND

[0002] Hydrogen energy, as a green energy, has the characteristics of clean and environmental protection, renewable, high energy density and wide application. Hydrogen energy has a wide application prospect in the fields of transportation, power and industry, can significantly reduce carbon emissions, reduce the proportion of fossil energy use, thereby reduce the emission of carbon dioxide, and has important significance for China to achieve carbon peak and carbon neutral. Promoting energy-saving and low-carbon transportation tools is an important part of accelerating the construction of a low-carbon transportation system, and promoting the construction of hydrogen refueling stations is an important measure to achieve this goal.

[0003] Although China has the largest number of hydrogen refueling stations in the world, most of the hydrogen refueling stations in China are gas hydrogen refueling stations. Compared with gas hydrogen refueling stations, liquid hydrogen refueling stations have many advantages: high storage and transportation efficiency; low storage pressure, reducing the safety risk of equipment and pipelines; avoiding the risk of high-pressure gas hydrogen leakage, improving the safety of hydrogen refueling stations; using liquid hydrogen pumps for pressurization, which has lower energy consumption than compressors in gas hydrogen refueling stations; using the low-temperature cold energy of liquid hydrogen for hydrogen precooling to improve the refueling efficiency; and small land occupation. The liquid hydrogen pump is a key equipment in the liquid hydrogen refueling station, and its performance and quality have a direct impact on the operating efficiency and safety of the hydrogen refueling station.

[0004] Static heat leakage of the liquid hydrogen pressurization pump is the main reason for the evaporation of liquid hydrogen, which not only affects the system efficiency and leads to reduced economic efficiency, but also poses a safety hazard. Reducing the static heat leakage of the liquid hydrogen pressurization pump is also an important guarantee for achieving zero evaporation technology for hydrogen refueling systems in liquid hydrogen refueling stations. Optimizing the structure of the liquid hydrogen pressurization pump to reduce the static heat leakage is a traditional method. However, the structure of the liquid hydrogen pressurization pump needs to meet the operating requirements and structural safety strength requirements, and there is little room for further reducing the static heat leakage.

[0005] Therefore, how to reduce the static heat leakage of the liquid hydrogen pressurization pump has become a problem to be solved, and the present application is proposed based on this. SUMMARY

[0006] The purpose of the present application is to provide a liquid hydrogen pressurization device that uses a refrigerator to precool the liquid hydrogen pressurization pump, which can significantly reduce the static heat leakage of the liquid hydrogen pressurization pump, does not require modification of the liquid hydrogen pressurization pump, and ensures the safety of the system.

[0007] The purpose of the present application can be achieved by the following technical solutions:

[0008] A liquid hydrogen pressurization device, comprising:

[0009] a liquid hydrogen pressurization pump;

[0010] and a refrigerator cooling the liquid hydrogen pressurization pump.

[0011] Further, the liquid hydrogen pressurization pump comprises a cylinder, a piston, a pump pool and a housing, the pump pool is arranged around the cylinder and forms a liquid pool space. In operation, low pressure liquid hydrogen enters the pump pool from a low pressure liquid hydrogen inlet, is compressed by the piston in the cylinder to high pressure, and is discharged from a high pressure liquid hydrogen outlet as high pressure liquid hydrogen; static heat leakage of the liquid hydrogen pressurization pump causes the low pressure liquid hydrogen in the pump pool to evaporate into hydrogen gas, which is discharged from a low pressure hydrogen gas outlet to maintain the pressure in the pump pool. Here, the space between the pump pool and the housing is vacuum, and the static heat leakage of the liquid hydrogen pressurization pump mainly comes from the solid thermal conduction of the components such as the piston and the cylinder which contact liquid hydrogen and the environment at the same time, and the radiation heat leakage between the pump pool and the housing.

[0012] Further, the refrigerator is a single-stage refrigeration structure, a two-stage refrigeration structure or more.

[0013] Further, the refrigerator is a single-stage refrigerator, and the refrigeration temperature of the refrigerator is higher than the saturation temperature of liquid hydrogen, and the cylinder and the piston are pre-cooled by the refrigerator to reduce the heat leakage of the liquid hydrogen pressurization pump. The refrigerator in this temperature range is relatively low in price and economical. The refrigerator pre-cools the cylinder, which reduces the temperature difference of the heat conduction leakage caused by the cylinder and the piston from the liquid hydrogen temperature range to the ambient temperature range to the temperature range of the refrigeration temperature of the refrigerator, thereby significantly reducing the static heat leakage of the liquid hydrogen pressurization pump.

[0014] Further, the refrigerator is a single-stage refrigerator, and the refrigeration temperature of the refrigerator is lower than the saturation temperature of liquid hydrogen, and the cylinder and the piston are pre-cooled by the refrigerator, so that the hydrogen gas evaporated in the pump pool is liquefied by the refrigerator.

[0015] Further, the refrigerator is a two-stage refrigerator, comprising a first-stage refrigerator and a second-stage refrigerator, and the refrigeration temperature of the first-stage refrigerator is higher than the refrigeration temperature of the second-stage refrigerator, and the first-stage refrigerator and the second-stage refrigerator are configured to cool the regions of the cylinder and the piston close to room temperature and close to low temperature, respectively.

[0016] More preferably, the refrigeration temperature of the first-stage refrigerator and the second-stage refrigerator is higher than the saturation temperature of liquid hydrogen to reduce the heat leakage of the liquid hydrogen pressurization pump.

[0017] More preferably, the refrigeration temperature of the second-stage refrigerator is lower than the saturation temperature of liquid hydrogen, so that the hydrogen gas is condensed into liquid hydrogen to reduce the evaporation of liquid hydrogen. The first-stage refrigerator pre-cools the cylinder, which reduces the temperature difference of the heat conduction leakage caused by the cylinder and the piston from the liquid hydrogen temperature range to the ambient temperature range to the temperature range of the refrigeration temperature of the refrigerator, and the second-stage refrigerator cools the evaporated hydrogen gas, which liquefies the hydrogen gas into liquid hydrogen, thereby realizing zero evaporation of the liquid hydrogen pressurization pump. Due to the addition of the first-stage pre-cooling, the required refrigeration capacity of the second-stage is reduced.

[0018] Further, a radiation screen is additionally arranged between the pump pool and the shell, and the radiation screen is cooled by the refrigerator. The radiation screen is cooled by the refrigerator, so that the radiation heat transfer temperature difference of the liquid hydrogen pressurizing pump is reduced from the liquid hydrogen temperature zone to the ambient temperature to the liquid hydrogen temperature zone to the refrigeration temperature, effectively reducing the radiation heat leakage and further reducing the static heat leakage of the liquid hydrogen pressurizing pump.

[0019] Further, the refrigerator is a pulse tube refrigerator, a Stirling refrigerator or a GM refrigerator.

[0020] Compared with the prior art, the present application has the following advantages:

[0021] (1) The liquid hydrogen pressurizing pump is cooled by the refrigerator, so that the evaporation amount of the liquid hydrogen in the pump pool of the liquid hydrogen pressurizing pump during shutdown is reduced. Low evaporation or no evaporation of the liquid hydrogen pressurizing pump is an important guarantee for zero evaporation of the liquid hydrogen filling station system.

[0022] (2) The present application can pursue economy, and a low-temperature zone refrigerator with low price is used to precool the liquid hydrogen pump, so that the static heat leakage of the liquid hydrogen pump from the liquid hydrogen temperature zone to the ambient temperature is changed to the static heat leakage from the liquid hydrogen temperature zone to the refrigeration temperature of the refrigerator, and the static heat leakage of the liquid hydrogen pressurizing pump is greatly reduced; and the system performance can be pursued, and a liquid hydrogen temperature zone refrigerator is used to liquefy the evaporated liquid hydrogen, so that zero evaporation of the liquid hydrogen pressurizing pump is realized. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 FIG. 1 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0024] Figure 2 FIG. 2 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0025] Figure 3 FIG. 3 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0026] Figure 4 FIG. 4 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0027] Figure 5 FIG. 5 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0028] Figure 6 FIG. 6 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0029] Figure 7 FIG. 7 is a structural schematic view of a liquid hydrogen pressurizing device according to an embodiment of the present application;

[0030] Marked in the figure:

[0031] 1 - Liquid hydrogen pressurization pump; 11 - Piston; 12 - Cylinder; 13 - Pump bowl; 14 - Housing; 15 - Low pressure liquid hydrogen inlet; 16 - Low pressure gaseous hydrogen outlet; 17 - High pressure liquid hydrogen outlet; 2 - Refrigerator; 21 - Refrigerator first stage; 22 - Refrigerator second stage; 3 - Radiant screen. DETAILED DESCRIPTION

[0032] The application will be described in greater detail with reference to the accompanying drawings and specific embodiments. The embodiments are implemented on the premise of the technical solutions of the application, and detailed implementation and specific operation processes are given, but the protection scope of the application is not limited to the following embodiments.

[0033] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0035] In the following embodiments, if there is no special description of the function parts or structures, it means that they are all conventional parts or conventional structures adopted in the art to realize the corresponding functions.

[0036] Embodiment 1

[0037] A liquid hydrogen pressurization device, as shown in Figure 1 includes a liquid hydrogen pressurization pump 1 and a refrigerator 2, and the refrigerator 2 cools the liquid hydrogen pressurization pump 1.

[0038] The liquid hydrogen pressurizing pump 1 is a reciprocating piston pressurizing pump, usually with a two-stage structure, including a piston 11, a cylinder 12, a pump pool 13, an outer shell 14, a low-pressure liquid hydrogen inlet 15, a low-pressure gaseous hydrogen outlet 16, and a high-pressure liquid hydrogen outlet 17. The low-pressure liquid hydrogen enters the pump pool 13 from the low-pressure liquid hydrogen inlet 15, is compressed by the piston 11 in the cylinder 12 to high pressure, and the compressed high-pressure liquid hydrogen is discharged from the high-pressure liquid hydrogen outlet 17. Part of the liquid hydrogen in the pump pool 13 evaporates into gaseous hydrogen due to the static heat leakage of the liquid hydrogen pressurizing pump 1, and the gaseous hydrogen is discharged from the low-pressure gaseous hydrogen outlet 16.

[0039] The liquid hydrogen pressurizing pump 1 is an important component of the hydrogenation system of the liquid hydrogen hydrogenation station, and the heat load caused by the liquid hydrogen pressurizing pump 1 is an important obstacle to realizing zero evaporation of the hydrogenation system. The static heat leakage of the liquid hydrogen pressurizing pump 1 mainly comes from the solid heat conduction of the piston 11, the cylinder 12 and other components that simultaneously contact liquid hydrogen and the environment, and the radiation heat leakage between the pump pool 13 and the outer shell 14. The pump pool 13 and the outer shell 14 are in vacuum.

[0040] The refrigerator 2 is a single-stage refrigerator, and the refrigeration temperature of the refrigerator 2 is higher than the liquid hydrogen temperature zone. The single-stage refrigerator with a refrigeration temperature higher than the liquid hydrogen temperature zone has a lower price and a high cost performance. The refrigerator 2 pre-cools the cylinder 12, so that the heat conduction temperature difference between the cylinder 12 and the piston 11 is reduced to the liquid hydrogen temperature zone to the refrigerator refrigeration temperature, and the heat conduction from room temperature to the refrigerator refrigeration temperature is cooled by the refrigerator 2.

[0041] The pre-cooling position of the refrigerator 2 is determined by the refrigeration temperature and the refrigeration capacity of the refrigerator 2. If the refrigeration temperature of the refrigerator 2 is high and the refrigeration capacity is small, the pre-cooling position is close to the room temperature end of the cylinder 12. If the refrigeration temperature of the refrigerator 2 is low and the refrigeration capacity is large, the pre-cooling position is closer to the low temperature end of the cylinder 12. The lower the refrigeration temperature and the larger the refrigeration capacity of the refrigerator 2, the smaller the heat leakage of the cylinder 12 and the piston 11.

[0042] The refrigerator can be a pulse tube refrigerator, a Stirling refrigerator, or a GM refrigerator

[0043] Example 2

[0044] A liquid hydrogen pressurizing device, as shown in Figure 2 The difference between the example 1 and the example 2 is that the refrigerator 2 is a single-stage refrigerator with a refrigeration temperature lower than the liquid hydrogen temperature zone. The refrigerator 2 needs to have a large refrigeration capacity and a low refrigeration temperature, and the refrigerator 2 directly condenses the evaporated gaseous hydrogen into liquid hydrogen to realize zero evaporation of the liquid hydrogen pressurizing pump 1. At this time, the refrigeration capacity of the refrigerator 2 needs to be greater than the static heat leakage of the liquid hydrogen pressurizing pump 1.

[0045] Example 3

[0046] A liquid hydrogen pressurizing device, as shown in Figure 3As shown, the difference from example 1 is that a radiation shield 3 is installed between the pump pool 13 and the outer shell 14, and the radiation shield 3 is cooled by the refrigerator 2 at the temperature of the refrigeration temperature of the refrigerator. Since the radiation heat transfer is the difference of the temperature to the fourth power, after the radiation shield 3 is installed, the radiation heat transfer leakage heat of the liquid hydrogen pressurizing pump 1 is significantly reduced, the static leakage heat of the liquid hydrogen pressurizing pump 1 is further reduced, and the required cooling capacity of the radiation shield 3 is provided by the refrigerator 2.

[0047] Example 4

[0048] A liquid hydrogen pressurizing device, as shown in Figure 4 As shown, the difference from example 1 is that the refrigerator 2 is a two-stage refrigerator, the first stage refrigeration temperature is higher than the second stage refrigeration temperature, and the second stage refrigeration temperature is higher than the liquid hydrogen temperature. The first stage and the second stage of the two-stage refrigerator 2 are used for staged pre-cooling of the cylinder 12. The temperature difference of the heat conduction of the cylinder 12 and the piston 11 of the liquid hydrogen pressurizing pump 1 is reduced to the difference between the second stage refrigeration temperature and the liquid hydrogen temperature, effectively reducing the static leakage heat of the liquid hydrogen pressurizing pump 1. The heat conduction leakage heat from the room temperature end of the cylinder 12 and the piston 11 to the pre-cooling place of the first stage of the refrigerator 21 is cooled by the refrigeration capacity of the first stage of the refrigerator 21, and the heat conduction leakage heat from the pre-cooling place of the first stage to the pre-cooling place of the second stage is cooled by the refrigeration capacity of the second stage of the refrigerator 22.

[0049] The use of the two-stage refrigerator 2 can obtain a lower refrigeration temperature, and the staged pre-cooling can reduce the required refrigeration capacity of the low temperature stage, greatly reducing the required cost of the refrigerator 2.

[0050] Example 5

[0051] A liquid hydrogen pressurizing device, as shown in Figure 5 As shown, the difference from example 4 is that a radiation shield 3 is installed between the pump pool 13 and the outer shell 14, and the radiation shield 3 is cooled by the first stage of the refrigerator 21 at the temperature of the refrigeration temperature of the first stage of the refrigerator. After the radiation shield 3 is installed, the radiation heat transfer leakage heat of the liquid hydrogen pressurizing pump 1 is significantly reduced, the required refrigeration capacity of the second stage of the refrigerator 22 is further reduced, and the required cooling capacity of the radiation shield 3 is provided by the first stage of the refrigerator 21. The required refrigeration capacity of the low temperature stage is transferred to the high temperature stage, which can improve the efficiency of the refrigerator 2 and reduce the required cost of the refrigerator 2.

[0052] Example 6

[0053] A liquid hydrogen pressurizing device, as shown in Figure 6As shown, different from example 2 is that the refrigerator 2 adopts a two-stage refrigerator, the first stage refrigeration temperature of the refrigerator is higher than the second stage refrigeration temperature, and the second stage refrigeration temperature is lower than the liquid hydrogen temperature. The cylinder 12 is pre-cooled by the first stage 21 of the refrigerator, and the second stage 22 of the refrigerator directly condenses the evaporated gaseous hydrogen into liquid hydrogen, realizing zero evaporation of the liquid hydrogen pressurizing pump 1. The two-stage liquid hydrogen temperature zone refrigerator is cheaper than the single-stage liquid hydrogen temperature zone refrigerator, and has low technical requirements. Since the cylinder 12 is pre-cooled by the first stage 21 of the refrigerator, the required refrigeration capacity of the second stage 22 of the refrigerator is greatly reduced, further reducing the cost of the refrigerator.

[0054] Example 7

[0055] A liquid hydrogen pressurizing device, as shown in Figure 7 As shown, different from example 6 is that a radiation shield 3 is additionally arranged between the pump pool 13 and the shell 14, the radiation shield 3 is cooled by the first stage 21 of the refrigerator, and the temperature is the first stage refrigeration temperature of the refrigerator. After the radiation shield 3 is additionally arranged, the radiation heat transfer leakage heat of the liquid hydrogen pressurizing pump 1 is significantly reduced, further reducing the required refrigeration capacity of the second stage 22 of the refrigerator, and the required cooling capacity of the radiation shield 3 is provided by the first stage 21 of the refrigerator. The required refrigeration capacity of the second stage 22 of the refrigerator is further reduced, further reducing the cost of the refrigerator.

[0056] The above description of the examples is for the purpose of enabling and using the invention for those of ordinary skill in the art. Those skilled in the art can easily make various modifications to these examples, and apply the general principles described herein to other examples without creative labor. Therefore, the present application is not limited to the above examples, and improvements and modifications made by those skilled in the art based on the disclosure of the present application without departing from the scope of the present application should be within the scope of protection of the present application.

Claims

1. A liquid hydrogen pressurizing device characterized by comprising: The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump.

2. The liquid hydrogen pressurizing apparatus according to claim 1, wherein The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump.

3. The liquid hydrogen pressurizing apparatus according to claim 1, wherein The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump.

4. The liquid hydrogen pressurizing apparatus according to claim 1, wherein The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump.

5. The liquid hydrogen pressurizing apparatus according to claim 1, wherein The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates to a liquid hydrogen pressurization pump and a cryocooler for cooling the liquid hydrogen pressurization pump. The application relates

Images