A liquid hydrogen container insulation system

Abstract

The application is suitable for the field of hydrogen energy efficient storage technology, and provides a liquid hydrogen container heat insulation system, which comprises a liquid hydrogen container containing an evaporated hydrogen gas cold energy utilization system, a self-pressurization system and the like. The exhaust valve at the top of the liquid hydrogen container is connected with the inlet of the first heat exchange pipe, the outlet of the first heat exchange pipe is connected with the inlet of the second heat exchange sleeve pipe, and the outlet of the second heat exchange sleeve pipe is connected with the inlet of the vaporizer. The inner and outer pipe interlayers of the second heat exchange sleeve pipe are filled with cold storage materials. The evaporated hydrogen gas cold energy is stored by using the cold storage materials, so that the temperature of the second cold screen can be maintained at a low temperature level for a long time, and the rewarming process of the first cold screen is greatly delayed, so that the effective time of the first cold screen and the second cold screen is effectively prolonged. The application overcomes the limitations of the discontinuity, large fluctuation and poor heat exchange performance of the BOG exhaust on the actual application of the gas cold screen, and effectively reduces the environmental heat leakage of the vehicle-mounted liquid hydrogen container.

Description

TECHNICAL FIELD

[0001] The application relates to a hydrogen energy efficient storage technology field, in particular to a liquid hydrogen container heat insulation system. BACKGROUND

[0002] With the increasing environmental protection awareness of people, it is an increasingly urgent task to find new renewable clean energy to replace the use of traditional fossil energy. Liquid hydrogen is a kind of renewable clean energy with high energy density. At present, major automobile manufacturers at home and abroad have carried out certain research and development and trial production on commercial vehicles using liquid hydrogen as energy, but the efficient heat insulation technology of liquid hydrogen is still one of the main reasons restricting its popularization.

[0003] Although the traditional high-vacuum multilayer insulation method can effectively reduce the heat leakage of the vehicle-mounted liquid hydrogen container, the heat leakage of the liquid hydrogen container still has an undeniable influence on the evaporation of the liquid hydrogen in the container. How to effectively reduce the external heat leakage of the container and prolong the lossless storage time of the liquid hydrogen in the vehicle-mounted liquid hydrogen container is of great significance to the large-scale application of the liquid hydrogen fuel cell vehicle. At present, the existing vehicle-mounted liquid hydrogen container usually has two processing methods for the self-evaporation hydrogen gas (BOG) exhaust: one is to directly exhaust the BOG gas in the tank outside the container after the container reaches the set pressure, and then the gas is heated by a vaporizer and stored in a buffer tank; the other is to use a cold screen structure to utilize the cold energy of the BOG exhaust, and then heat it by a vaporizer and enter the buffer tank. The cold screen structure is usually located inside the high-vacuum multilayer insulation layer, and the cold energy of the BOG exhaust is used to reduce the temperature of the cold screen, so as to reduce the temperature difference between the cold screen and the inner container and achieve the purpose of reducing the heat leakage of the liquid hydrogen container. However, the cold screen structure has the following disadvantages in actual application: ① discontinuity: the BOG exhaust is not a continuous process during the operation of the vehicle-mounted liquid hydrogen container, and the BOG gas is only exhausted after the pressure in the container reaches the set pressure. The time interval between adjacent two BOG exhausts is relatively long, and although the cold screen structure can utilize the cold energy of the BOG exhaust, it cannot store the cold energy. The cold screen will soon be rewarmed after being effective in a short time, thereby losing the effect of reducing the heat leakage of the container; ② large fluctuation: after the 20K hydrogen gas is exhausted from the top and passes through the cold screen structure, the temperature gradually rises, and it is difficult to determine the optimal cold screen position in the vacuum interlayer; ③ poor heat exchange performance: the cold screen is arranged in the vacuum interlayer, and the vacuum degree is usually 10 -2 Pa, and the cold energy of the cold screen light pipe can only be transmitted by radiation heat conduction, and the cold energy utilization rate is low. SUMMARY

[0004] The present application aims to provide a liquid hydrogen container heat insulation system, which stores the cold energy of self-evaporation gas (BOG) through the phase change of the cold storage material, enables the cold screen in contact with the heat exchange pipe coated with the cold storage material to be maintained at the phase change point temperature of the cold storage material, and classifies the use of the cold energy of the evaporated hydrogen, thereby prolonging the effective time of the cold screen, improving the utilization rate of the cold energy of the evaporated hydrogen, and achieving the purpose of effectively reducing the heat leakage of the liquid hydrogen container, so as to solve the problems in the above background art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions.

[0006] A liquid hydrogen container heat insulation system, comprising: an inner container, which internally contains liquid hydrogen;

[0007] An outer container, which is sleeved outside the inner container;

[0008] A high-vacuum multilayer insulation layer, which is arranged between the inner container and the outer container; wherein the high-vacuum multilayer insulation layer comprises a vacuum layer, multilayer reflective screens and spacers, and the multilayer reflective screens are arranged in the vacuum layer; the spacers are filled between adjacent reflective screens;

[0009] A primary heat exchange pipe, which is arranged in the spacers between the two layers of reflective screens close to the inner container and is spirally wound along the circumferential direction of the inner container, and the input end of the primary heat exchange pipe is in communication with the top exhaust port of the inner container;

[0010] A secondary heat exchange sleeve pipe, which is arranged in the spacers between the two layers of reflective screens close to the outer container and is wound along the circumferential direction of the inner container, and the input end of the secondary heat exchange sleeve pipe is in communication with the output end of the primary heat exchange pipe; the secondary heat exchange sleeve pipe is composed of an inner pipe and an outer pipe, and the cold storage material is filled between the inner pipe and the outer pipe; the secondary heat exchange sleeve pipe is used for outputting the evaporated hydrogen.

[0011] As a further scheme of the present application, the outer pipe of the secondary heat exchange sleeve pipe is provided with a cold storage material filling port and a cold storage material outlet port, which are used for supplementing or taking out the cold storage material in the inner pipe and the outer pipe.

[0012] As a further scheme of the present application, the winding direction of the secondary heat exchange sleeve pipe is opposite to the winding direction of the primary heat exchange pipe.

[0013] As a further scheme of the present application, one end of the inner container is connected with the outer container through a first support, and the other end of the inner container is connected with the outer container through a second support.

[0014] As a further scheme of the present application: the cold storage material is a phase change material with phase transition characteristics or a single-phase material with large specific heat capacity and fluidity, and the cold storage material filled in the secondary heat exchange sleeve is filled in a segmented manner. The phase change material can be an organic phase change material, an inorganic phase change material, a composite phase change material, and nitrogen working medium, etc. The organic phase change material includes paraffin, ester acid, and high molecular compound, etc. The inorganic phase change material can include sodium sulfate decahydrate (Na2SO4-10H2O) added with other salt to control the melting point. The composite phase change material can include a ternary organic composite phase change cold storage material prepared from n-decanoic acid, dodecanol, and tetradecane; a capric alcohol-lauric acid composite phase change material; a tetradecane-dodecanol composite phase change material; an octanoic acid-dodecanol composite phase change material, etc. The single-phase material with large specific heat capacity and fluidity can be helium working medium, argon working medium, etc.

[0015] As a further scheme of the present application: the cold energy utilization temperature zone of the primary heat exchange pipe is 20-70K, and the cold energy utilization temperature zone of the secondary heat exchange sleeve is 70-270K.

[0016] As a further scheme of the present application: the secondary heat exchange sleeve is made of stainless steel material.

[0017] As a further scheme of the present application: further comprising a self-pressurization circulation system arranged on the inner container and used for pressurizing the inside of the inner container.

[0018] As a further scheme of the present application: the self-pressurization circulation system comprises a fourth switch valve, a self-pressurization vaporizer, and a second electromagnetic valve; the fourth switch valve is arranged outside the outer container and communicates with the bottom of the inner container; the output end of the fourth switch valve is connected to the input end of the self-pressurization vaporizer; the output end of the self-pressurization vaporizer is connected to the input end of the second electromagnetic valve, and the output end of the second electromagnetic valve communicates with the input end of the first vent valve and the upper gas phase region of the inner container through a three-way joint.

[0019] As a further scheme of the present application: further comprising a liquid hydrogen supply system, which further comprises a third switch valve, the input end of the third switch valve communicates with the bottom of the inner container, and the third switch valve is arranged outside the outer container, the output end of the third switch valve is connected to the input end of the vaporizer; the output end of the vaporizer communicates with the input end of the compressor and the input end of the buffer tank in sequence; the output end of the buffer tank has two paths, one of which is connected to the input end of the second vent valve, and the other is connected to the fuel cell system.

[0020] As a further scheme of the present application: the output end of the compressor further communicates with the input end of the first vent valve, and the first vent valve and the second vent valve both communicate with a hydrogen discharge treatment system.

[0021] Compared with the prior art, the present application has the beneficial effects that: the cold energy of the evaporated hydrogen is utilized in multiple stages, the BOG exhaust cold energy and the phase change cold storage characteristics of the cold storage material are utilized to the maximum extent, the BOG cold energy is stored by utilizing the latent heat of phase change of the cold storage material in the phase state transition process, the temperature of the secondary cold screen can be maintained at a lower temperature level (the phase change point temperature of the cold storage material) for a long time, and the rewarming process of the primary cold screen is greatly delayed, so that the effective time of the primary cold screen and the secondary cold screen is effectively prolonged, and the purpose of effectively reducing the heat leakage of the vehicle-mounted liquid hydrogen container is achieved. The present application has the advantages of simple structure, easy realization in technology, low cost, practical application value, greatly prolonged effective time of the cold screen, overcoming of the limitation of the discontinuity, large fluctuation and poor heat exchange performance of the BOG exhaust on the actual application of the gas cold screen, and effective reduction of the heat load into the container during the long-term storage of the vehicle-mounted liquid hydrogen container, which provides a new idea for the high-efficiency thermal insulation technology of the vehicle-mounted liquid hydrogen container. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a structural schematic diagram of a liquid hydrogen container thermal insulation system according to an embodiment of the present application.

[0023] In the figure: 1 - inner container, 2 - outer container, 3 - vacuum layer, 4 - reflective screen, 5 - spacer, 6 - first support, 7 - second support, 8 - primary heat exchange pipe, 9 - secondary heat exchange sleeve, 10 - liquid level meter, 11 - first on-off valve, 12 - second on-off valve, 13 - vaporizer, 14 - buffer tank, 15 - first electromagnetic valve, 16 - third on-off valve, 17 - fourth on-off valve, 18 - self-pressurizing vaporizer, 19 - control system, 20 - second electromagnetic valve, 21 - first vent valve, 22 - flow meter, 23 - first check valve, 24 - compressor, 25 - second vent valve, 26 - fifth on-off valve, 27 - third electromagnetic valve, 28 - second check valve, 29 - vacuumizing port, 30 - sixth on-off valve, 91 - cold storage material filling port, 92 - cold storage material outlet port. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0025] Embodiment 1

[0026] Please refer to Figure 1 , in the embodiment 1 of the present application, a structural diagram of a liquid hydrogen container thermal insulation system provided by the embodiment of the present application is provided, which comprises: an inner container 1 containing liquid hydrogen.

[0027] The outer container 2 is sleeved outside the inner container 1; one end of the inner container 1 is connected with the outer container 2 through the first support 6, and the other end of the inner container 1 is connected with the outer container 2 through the second support 7; the inner container connected with the outer container through the first support 6 is fixed relative to the outer container, and the inner container connected with the outer container through the second support 7 can move relative to the outer container, so that a certain moving space is reserved for thermal expansion and contraction of the inner container when affected by temperature difference stress.

[0028] The high-vacuum multilayer insulation layer is arranged between the inner container 1 and the outer container 2; wherein the high-vacuum multilayer insulation layer comprises a vacuum layer 3, multilayer reflective screens 4 and spacers 5, and the multilayer reflective screens 4 are arranged in the vacuum layer 3; the spacers 5 are filled between adjacent reflective screens 4;

[0029] The primary heat exchange pipe 8 is arranged in the spacer 5 between the two reflective screens 4 close to the inner container 1 and is arranged in a spiral along the circumferential direction of the inner container 1; the input end of the primary heat exchange pipe 8 is communicated with the exhaust port at the top of the inner container 1;

[0030] The secondary heat exchange jacket pipe 9 is arranged in the spacer 5 between the two reflective screens 4 close to the outer container 2 and is arranged in a spiral along the circumferential direction of the inner container 1; the input end of the secondary heat exchange jacket pipe 9 is communicated with the output end of the primary heat exchange pipe 8; the secondary heat exchange jacket pipe 9 is composed of an inner pipe and an outer pipe, and the inner pipe and the outer pipe are filled with cold storage materials between the layers to store the cold energy of the BOG exhaust; the secondary heat exchange jacket pipe 9 is used for outputting the evaporated hydrogen (BOG).

[0031] The cold energy of the BOG exhaust is recycled by arranging the heat exchange pipes in different layers of the multilayer insulation layer; the low-temperature hydrogen exchanges heat with the reflective screens in the primary heat exchange pipe 8, so that the temperature of the reflective screens is reduced to 20-70K, and the reflective screens act as a primary cold screen; then the low-temperature hydrogen enters the inner pipe of the secondary heat exchange jacket pipe 9 close to the outer container, exchanges heat with the cold storage materials in the inner pipe, and continuously reduces the temperature of the cold storage materials to below the phase transition point temperature; at the same time, the secondary heat exchange jacket pipe 9 exchanges heat with the reflective screens in contact, so that the temperature of the reflective screens is reduced to 70-270K, and the reflective screens act as a secondary cold screen; when the first switch valve 11 is closed, the temperature of the cold storage materials will be maintained at the phase transition point temperature when the secondary heat exchange jacket pipe 9 is warmed up to the phase transition point temperature of the cold storage materials; the secondary cold screen in contact with the outer pipe of the secondary heat exchange jacket pipe 9 can be maintained at the phase transition point temperature of the cold storage materials for a long time through the latent heat absorption in the phase transition process, so as to prolong the effective time of the secondary cold screen; in addition, due to the prolongation of the effective time of the secondary cold screen, the heat leakage into the primary cold screen is also reduced, so that the warming-up process of the primary cold screen is also greatly slowed down, thereby prolonging the effective time of the primary cold screen at the same time.

[0032] The application makes full use of the BOG exhaust cold energy and the phase change cold storage characteristics of the cold storage material, stores the BOG cold energy by using the latent heat of phase change of the cold storage material in the phase state transition process, so that the temperature of the secondary cold screen can be maintained at a lower temperature level (the phase change point temperature of the cold storage material) for a long time, and the rewarming process of the primary cold screen is greatly delayed, so that the effective time of the primary cold screen and the secondary cold screen is effectively prolonged, and the purpose of effectively reducing the long-term storage heat leakage of the vehicle-mounted liquid hydrogen container is achieved. The application has a simple structure, is easy to implement in technology, has a low cost, has a practical application value, can greatly prolong the effective time of the cold screen, overcomes the limitation of the discontinuity, large fluctuation and poor heat exchange performance of the BOG exhaust on the actual application of the cold screen, and effectively reduces the heat load into the container in the long-term storage process of the vehicle-mounted liquid hydrogen container.

[0033] In the embodiment of the application, the outer pipe of the secondary heat exchange sleeve pipe 9 is provided with a cold storage material filling port 91 and a cold storage material outlet port 92 for supplementing or taking out the cold storage material in the inner-outer pipe interlayer.

[0034] In the embodiment of the application, the cold storage material is a phase change material with phase state transition characteristics or a single-phase material with large specific heat capacity and fluidity, and the cold storage material of the secondary heat exchange sleeve pipe 9 can be different cold storage materials filled in a segmented manner. The phase change material can be an organic phase change material, an inorganic phase change material, a composite phase change material, nitrogen working medium, etc. The organic phase change material includes paraffin, ester acid, high molecular compound, etc. The inorganic phase change material can include sodium sulfate decahydrate (Na2SO4-10H2O) added with other salt type control melting point. The composite phase change material can include a ternary organic composite phase change cold storage material prepared from n-decanoic acid, dodecanol and tetradecane, a capric alcohol-lauric acid composite phase change material, a tetradecane-dodecanol composite phase change material, an octanoic acid-dodecanol composite phase change material, etc. The single-phase material with large specific heat capacity and fluidity can be helium working medium, argon working medium, etc. In the embodiment of the application, the secondary heat exchange sleeve pipe 9 is a low-temperature sleeve pipe filled with replaceable cold storage material in the inner-outer pipe interlayer.

[0035] In the embodiment of the application, the primary heat exchange pipe 8 and the secondary heat exchange sleeve pipe 9 are arranged between different reflective screens 4 interlayers of the high-vacuum multi-layer insulation layer, respectively.

[0036] In the embodiment of the application, the winding direction of the secondary heat exchange sleeve pipe 9 is arranged in the opposite direction of the winding direction of the primary heat exchange pipe 8, so as to improve the heat exchange efficiency.

[0037] In the embodiment of the application, the inner container 1 is further provided with a liquid level meter 10, and the liquid level meter 10 penetrates through the whole inner container 1. The liquid level meter 10 is a column type liquid level meter.

[0038] In the embodiment of the present application, the present application further comprises a self-pressurization circulation system arranged on the inner container 1 for pressurizing the inside of the inner container 1.

[0039] The self-pressurization circulation system comprises a fourth switch valve 17, a self-pressurization vaporizer 18 and a second electromagnetic valve 20; the fourth switch valve 17 is arranged outside the outer container 2 and communicates with the bottom of the inner container 1; the output end of the fourth switch valve 17 is connected to the input end of the self-pressurization vaporizer 18; the output end of the self-pressurization vaporizer 18 is connected to the input end of the second electromagnetic valve 20, and the output end of the second electromagnetic valve 20 communicates with the input end of a first vent valve 21 and the upper gas phase region of the inner container 1 through a tee joint. Specifically, a flow meter 22 is further arranged between the input end of the first vent valve 21 and the tee joint. A first pressure gauge is arranged on the communication pipeline between the tee joint and the inner container 1. The communication pipeline between the tee joint and the inner container 1 further communicates with the input end of a sixth switch valve 30. The output end of the sixth switch valve 30 can communicate with a hydrogen discharge treatment system.

[0040] Specifically, when the fourth switch valve 17 and the second electromagnetic valve 20 are opened, liquid hydrogen flows out of the container from the pipeline and enters the input end of the self-pressurization vaporizer 18, and the liquid hydrogen evaporates into gas in the self-pressurization vaporizer 18 and then flows out of the output end, and the vaporized hydrogen reenters the air cushion region of the inner container 1 after passing through the second electromagnetic valve 20 and the first pressure gauge, so as to pressurize the inner container 1 and make the inside of the container reach a set pressure value. The self-pressurization circulation system is provided with a branch before the first pressure gauge, which is connected to the first vent valve 21 after passing through the flow meter, and is connected to the hydrogen discharge treatment part through the sixth switch valve 30 before entering the air cushion region of the container, so as to prevent the pipeline or the inner container 1 from overpressure.

[0041] The present application further comprises a liquid hydrogen supply system. The liquid hydrogen supply system comprises a vaporizer 13, which communicates with the output end of the secondary heat exchange sleeve 9 through a second switch valve 12. The vaporizer 13 supplies gas for the fuel cell system.

[0042] The vaporizer 13 can be an air temperature type vaporizer or a water bath type vaporizer.

[0043] In the embodiment of the present application, the liquid hydrogen supply system further comprises a third switch valve 16, the input end of which communicates with the bottom of the inner container 1, and the third switch valve 16 is arranged outside the outer container 2, and the output end of the third switch valve 16 is connected to the input end of the vaporizer 13.

[0044] Specifically, the output end of the vaporizer 13 is communicated with the input end of the first check valve 23, the compressor 24 and the input end of the buffer tank 14 in sequence; the output end of the buffer tank 14 is communicated with the input end of the second vent valve 25 in one branch and with the fuel cell system in another branch. The buffer tank 14 is further provided with a second pressure gauge. The one branch of the buffer tank 14 is connected to the input end of the second vent valve 25, for preventing overpressure of the pipeline and the buffer tank 14.

[0045] In the embodiment of the present application, the output end of the compressor 24 is further communicated with the input end of the first vent valve 21. The output end of the compressor 24 is communicated with the input end of the first vent valve 21 through the fifth switch valve 26, the third electromagnetic valve 27 and the second check valve 28.

[0046] Specifically, the output end of the buffer tank 14 is connected to the input end of the first electromagnetic valve 15, and the output end of the first electromagnetic valve 15 is connected to the input end of the pressure reducing valve; the output end of the pressure reducing valve is connected to the input end of the second vent valve 25, and the output end of the pressure reducing valve is also connected to the input end of the fuel cell system. The pipeline communicated with the output end of the pressure reducing valve and the fuel cell system is further provided with a third pressure gauge and a first thermometer. The first vent valve and the second vent valve are both communicated with the hydrogen discharge treatment system.

[0047] Specifically, when the third switch valve 16 is opened, liquid hydrogen flows out of the container and enters the vaporizer inlet, and the liquid hydrogen is evaporated into hydrogen gas in the vaporizer and then flows out of the outlet, and then is divided into two branches after passing through the first check valve 23 and the compressor 24. When the fifth switch valve 26 and the third electromagnetic valve 27 are opened, the hydrogen gas reaches the first vent valve 21 through the second check valve 28 and the flowmeter 22, and the first vent valve 21 prevents overpressure of the pipeline; in the other branch, the hydrogen gas enters the buffer tank 14. When the first electromagnetic valve 15 is opened, the hydrogen gas in the buffer tank 14 enters the fuel cell system for combustion after passing through the first electromagnetic valve 15, the third pressure gauge and the first thermometer. A branch connected to the second vent valve 25 is arranged after the first electromagnetic valve 15, for preventing overpressure of the pipeline and the buffer tank.

[0048] In the embodiment of the present application, the outer container 2 is further provided with a vacuumizing port 29.

[0049] In the embodiment of the present application, the present application further comprises a control system, and the liquid level meter 10, the first electromagnetic valve 15, the second electromagnetic valve 20 and the third electromagnetic valve 27 are all in communication connection with the control system.

[0050] The valves in the present application are all anti-explosion low-temperature valves. The anti-explosion low-temperature valves include low-temperature stop valves, low-temperature electromagnetic valves, low-temperature safety valves, low-temperature check valves and low-temperature pressure reducing valves.

[0051] In the embodiment of the present application, the first switch valve 11, the third switch valve 16, the fourth switch valve 17, the sixth switch valve 30, the fifth switch valve 26 and the second switch valve 12 can all be low-temperature stop valves. The first vent valve 21 and the second vent valve 25 can both be low-temperature safety valves. The pipeline material in the present application is stainless steel. The first vent valve 21 and the second vent valve 25 are both connected to a hydrogen discharge treatment system.

[0052] The working principle of the present application is as follows:

[0053] The inner container 1 is filled with a certain amount of liquid hydrogen. The upper part of the inner container 1 is a gas pillow area, and the lower part is a liquid hydrogen area. The inner container 1 has a BOG exhaust port at the top, which is connected to the first switch valve 11 outside the container. When the pressure in the container reaches the set upper limit value, the first switch valve 11 is opened, and the BOG gas is discharged from the exhaust port. The pressure in the inner container 1 gradually decreases. After the gas flows out of the exhaust port, it enters the primary heat exchange pipe 8. The low-temperature hydrogen gas exchanges heat with the reflector 4 in the primary heat exchange pipe 8, causing the temperature of the reflector 4 to decrease to 20-70K, which acts as a primary cold screen. After the low-temperature hydrogen gas completes heat exchange along the spiral primary heat exchange pipe 8, it enters another layer of secondary heat exchange sleeve 9 closer to the outer container side. The low-temperature hydrogen gas exchanges heat with the cold storage material in the inner tube, causing the temperature of the cold storage material to continuously decrease to below its phase transition point temperature. At the same time, the secondary heat exchange sleeve 9 exchanges heat with the reflector in contact, causing the temperature of the reflector to decrease to 70-270K, which acts as a secondary cold screen. After the low-temperature hydrogen gas completes heat exchange in the spiral secondary heat exchange sleeve 9 in the opposite direction of the primary heat exchange pipe 8, it flows out of the vehicle-mounted liquid hydrogen container outside, enters the vaporizer 13 inlet of the fuel supply pipeline through the second switch valve 12, and is heated and warmed up by the vaporizer 13 before entering the buffer tank 14 for storage.

[0054] When the pressure in the container decreases to the set standard value, the first switch valve 11 is closed. Subsequently, due to the heat leakage of the container, the primary cold screen and the secondary cold screen will gradually begin to warm up. When the temperature of the secondary heat exchange sleeve 9 increases to the phase transition point temperature of the cold storage material, the temperature of the cold storage material will be maintained at its phase transition point temperature. Through the absorption of heat during the phase transition process, the secondary cold screen in contact with the outer tube of the heat exchange sleeve can maintain the phase transition point temperature of the cold storage material for a long time, thereby prolonging the effective time of the secondary cold screen. In addition, due to the extension of the effective time of the secondary cold screen, the radiation heat leakage into the primary cold screen is reduced, greatly slowing down the warming-up process of the primary cold screen, thereby simultaneously prolonging the effective time of the primary cold screen.

[0055] In the description of the application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0056] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.

[0057] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0058] Although the embodiments of the present application have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and cannot be understood as a limitation on the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments within the scope of the present application.

Claims

1. A liquid hydrogen container insulation system, characterized in that, include: The inner container contains liquid hydrogen. The outer container is fitted over the outer part of the inner container; A high-vacuum multilayer insulation layer is disposed between the inner container and the outer container; wherein, the high-vacuum multilayer insulation layer includes a vacuum layer, multiple reflective screens and spacers, the multiple reflective screens are arranged in the vacuum layer; spacers are filled between adjacent reflective screens; A primary heat exchange tube is disposed in the spacer between the two layers of the reflective screen near the inner container and is spirally wound along the circumference of the inner container. The input end of the primary heat exchange tube is connected to the exhaust port at the top of the inner container. Furthermore, a secondary heat exchange sleeve is disposed in the spacer between the two layers of the reflective screen near the outer container, and is wound around the circumference of the inner container. The input end of the secondary heat exchange sleeve is connected to the output end of the primary heat exchange tube. The secondary heat exchange sleeve consists of an inner tube and an outer tube, and the interlayer between the inner tube and the outer tube is filled with a cold storage material. The cold storage material is a phase change material with phase transition characteristics. The secondary heat exchange sleeve is used to output evaporated hydrogen.

2. The liquid hydrogen container insulation system according to claim 1, characterized in that, The outer tube of the secondary heat exchanger is provided with a cold storage material filling port and a cold storage material outlet for replenishing or removing the cold storage material in the interlayer between the inner tube and the outer tube.

3. The liquid hydrogen container insulation system according to claim 2, characterized in that, The cold storage material filled inside the secondary heat exchanger tube is segmented.

4. The liquid hydrogen container insulation system according to claim 1, characterized in that, One end of the inner container is connected to the outer container via a first support, and the other end of the inner container is connected to the outer container via a second support.

5. The liquid hydrogen container insulation system according to claim 1, characterized in that, The winding direction of the secondary heat exchange sleeve is opposite to that of the primary heat exchange tube.

6. The liquid hydrogen container insulation system according to claim 5, characterized in that, It also includes a liquid hydrogen supply system, which includes a vaporizer connected to the output end of the secondary heat exchange bushing via a second switching valve.

7. The liquid hydrogen container insulation system according to claim 1, characterized in that, It also includes a self-pressurizing circulation system installed on the inner container for pressurizing the interior of the inner container.

8. The liquid hydrogen container insulation system according to claim 7, characterized in that, The self-pressurizing circulation system includes a fourth switching valve, a self-pressurizing vaporizer, and a second solenoid valve. The fourth switching valve is located outside the outer container and is connected to the bottom of the inner container. The output of the fourth switching valve is connected to the input of the self-pressurizing vaporizer. The output of the self-pressurizing vaporizer is connected to the input of the second solenoid valve. The output of the second solenoid valve is connected to the input of the first vent valve and the upper gas phase region of the inner container via a three-way valve.

9. The liquid hydrogen container insulation system according to claim 6, characterized in that, The liquid hydrogen supply system also includes a third switching valve. The input end of the third switching valve is connected to the bottom of the inner container, and the third switching valve is located outside the outer container. The output end of the third switching valve is connected to the input end of the vaporizer. The output end of the vaporizer is connected to the input end of the first check valve, the compressor, and the buffer tank in sequence. The output end of the buffer tank has two paths, one of which is connected to the input end of the second vent valve, and the other is connected to the fuel cell system.

10. A liquid hydrogen container insulation system according to claim 9, characterized in that, The output end of the compressor is also connected to the input end of the first vent valve, and both the first vent valve and the second vent valve are connected to the hydrogen emission treatment system.

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