Medium-pressure cryogenic liquid storage tank
By designing structures such as pressure balancers and air flow channels in the medium-pressure cryogenic liquid storage tank, the problems of vacuum insulation board damage and excessive pressure caused by the deterioration of the tank shell are solved, and the effective regulation and safety of the internal pressure of the tank are achieved. of storage.
Patent Information
- Application Number
- CN202411713146.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-01-24
AI Technical Summary
When the shell of the existing medium-pressure deep-cooled liquid storage tank deteriorates and cracks occur, the vacuum degree of the vacuum insulation plate layer may be destroyed, resulting in a decrease in the insulation effect, evaporation of the deep-cooled liquid, increasing the pressure inside the storage tank, and may cause safety accidents.
A medium -voltage deep -cold liquid storage tank is designed, which contains the structure of pressure balancer, piston, elastic ring, wind wheel and air flow channel. When the pressure in the storage tank is too large, the liquefaction steam acts on the piston through the pores, promoting the piston squeeze the elastic ring, separates the fixing sheet from the piston, and the liquefaction steam blows the wind wheel through a cluster cover, and rotate the activity cover to compress the cover cover. Spring, ventilation air passage, liquefied steam enters the elastic bag layer, and regulates pressure through the elastic foam layer.
It realizes the internal pressure regulation of the storage tank, prevents the problem of excessive pressure caused by the evaporation of cryogenic liquid, and avoids safety accidents. At the same time, the storage tank has good thermal insulation characteristics.
Smart Images
Figure CN119353582A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of cryogenic liquid storage, and in particular relates to a medium-pressure cryogenic liquid storage tank. Background Art
[0002] Medium-pressure cryogenic liquid refers to liquid substances formed by cooling substances to extremely low temperatures through deep freezing technology under medium pressure conditions. The temperature of these liquids is usually much lower than room temperature and can even reach several hundred degrees below zero. Medium-pressure cryogenic liquid storage tanks are widely used in aerospace, nuclear industry, metallurgy, medical and other fields. In the aerospace field, storage tanks are mainly used to store aerospace fuels such as liquid oxygen and liquid hydrogen; in the nuclear industry, storage tanks are used to store cryogenic substances such as liquid hydrogen; in the metallurgical and medical fields, storage tanks also play an important role, such as storing liquid nitrogen for cooling and preserving samples.
[0003] At present, the insulation method of medium-pressure cryogenic liquid storage tanks with high thermal insulation effect generally adopts a vacuum insulation structure with high thermal insulation effect. However, when using a tank that relies on a vacuum insulation structure to store cryogenic liquid, when the outer shell deteriorates over time and cracks appear, the vacuum degree of the vacuum layer may be destroyed. At this time, the insulation effect decreases and the cryogenic liquid will evaporate, thereby increasing the pressure inside the tank. If the pressure continues to rise and exceeds the bearing limit of the tank, it may cause a safety accident. Summary of the invention
[0004] The purpose of the present invention is to provide a medium-pressure cryogenic liquid storage tank for existing devices to solve the problems raised in the above-mentioned background technology.
[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a medium-pressure cryogenic liquid storage tank, comprising a storage tank shell, a pressure balancer is fixedly arranged above the interior of the storage tank shell, the pressure balancer is a hollow barrel-shaped structure, a fixing plate is welded to the lower end of the interior of the pressure balancer, a piston plate is slidably arranged above the fixing plate inside the pressure balancer, an elastic ring is glued above the outer periphery of the piston plate, a flow collecting cover is glued to the upper end of the elastic ring, a fixed shaft is fixedly arranged above the flow collecting cover in the pressure balancer, a wind wheel is sleeved on the middle section of the fixed shaft, the wind wheel is located inside the pressure balancer, and the pressure balancer An upper cover is welded to the top of the cover, a through slot is provided in the center of the upper cover, a blind slot is provided on one side of the through slot, a movable cover is provided obliquely above the blind slot, the movable cover completely covers the through slot in the horizontal direction, a spring is fixedly connected between the two opposite sides of the movable cover and the blind slot, a convex structure is provided at the lower end of the movable cover to ensure that the wind wheel will hit the convex structure when it rotates, so that the movable cover is compressed to the left by the impact force and the spring is displaced, a section of the movable cover is moved away from the through slot for ventilation, and an air flow channel is also welded on the upper part of the upper cover, and the area of the opening at the lower end of the air flow channel completely covers the air flow channel; The outer wall of the storage tank shell is composed of an outer shell, an aerogel insulation layer, a vacuum insulation board layer, a glass fiber insulation layer, a diene elastic foam layer, an elastic bag layer, an LNG elastic felt layer, a polyurethane foam layer and an inner liner from the outside to the inside. A connecting pipe is also inserted above the air flow channel, and the connecting pipe passes through the inner liner, the polyurethane foam layer and the LNG elastic felt layer to be connected to the elastic bag layer.
[0006] The present invention further illustrates that a plurality of through holes are provided on the fixing plate, and a plurality of through holes are also provided on the piston plate, and the through holes on the fixing plate are staggered with the through holes on the piston plate, which is beneficial for effectively blocking the airflow when the fixing plate contacts the piston plate, and allowing the airflow to pass when the fixing plate is separated from the piston plate.
[0007] The present invention further describes that the lower end of the focusing cover is a circular plate with the same inner diameter as the pressure balancer, the outer side of the focusing cover is tightly fitted to the inner wall of the pressure balancer and glued to each other, and a funnel-shaped opening design with a small top and a large bottom is provided in the center of the circular plate.
[0008] The present invention further illustrates that the interior of the storage tank shell is used to store cryogenic liquid, the interior of the storage tank shell stores cryogenic liquid, and the cryogenic liquid does not completely fill the interior of the storage tank shell, the cryogenic liquid evaporates to form liquefied gas, and the liquefied gas is located above the interior of the storage tank shell.
[0009] The present invention further states that the elastic bag layer is made of fluorosilicone rubber LS-2370U with a brittle temperature as low as -89°C, and the diene elastic foaming layer and the LNG elastic felt layer located on both sides of the elastic bag layer are elastic.
[0010] The present invention further illustrates that the upper section of the storage tank shell is provided with a first gas passage, and the first gas passage is provided with a first gas valve. The first gas passage completely penetrates from the outer shell through all insulation layers to the interior of the liner, and the first gas passage and the first gas valve are conducive to the staff to adjust the first gas valve to release the liquefied gas to adjust the gas pressure in the tank. The middle section of the storage tank shell is provided with a second gas passage, and the second gas passage is provided with a second gas valve. The second gas passage passes through the outer shell, the aerogel insulation layer, the vacuum insulation board layer, the glass fiber insulation layer and the diene elastic foaming layer to enter the interior of the elastic bag layer. The second gas passage and the second gas valve are conducive to the staff to adjust the second gas valve to release the liquefied gas inside the elastic bag layer. The lower section of the storage tank shell is provided with a liquid passage, and the liquid passage is provided with a liquid valve. The liquid passage penetrates from the outer shell through all insulation layers to the interior of the liner, and the liquid passage and the liquid valve are conducive to the staff to inject or export the cryogenic liquid into the interior of the storage tank shell.
[0011] The present invention further describes that the aerogel thermal insulation layer is made of organic-inorganic hybrid aerogel with a porosity of more than 90%, and the aerogel thermal insulation layer is tightly attached to the outer side of the vacuum insulation panel layer.
[0012] The present invention further describes a method for using a medium-pressure cryogenic liquid storage tank, which is characterized by: When the shell deteriorates and cracks appear, the vacuum degree of the vacuum insulation board layer may be destroyed, the insulation effect decreases, the cryogenic liquid evaporates, the liquefied vapor increases, and the pressure inside the liner increases. At this time, due to the increase in the pressure of the liquefied vapor above the storage tank shell, a part of the liquefied vapor will act on the piston plate through the through holes on the fixed plate. Due to the increase in pressure, the liquefied vapor pushes the piston plate upward to squeeze the elastic ring, so that the fixed plate is separated from the piston plate, and the liquefied vapor flows upward through the through holes of the fixed plate and the piston plate in turn. The concentrated flow through the focusing cover blows the wind wheel to rotate around the fixed axis. When the wind wheel rotates, it hits the raised structure under the movable cover, so that the movable cover is compressed to the left by the impact force and the spring is displaced. A section of the movable cover is removed from the through groove, and the liquefied vapor enters the air flow channel therefrom, and then enters the elastic bag layer from the air flow channel through the connecting pipe. As the liquefied vapor continuously enters the elastic bag layer, the diene elastic foaming layer and the LNG elastic felt layer are squeezed and elastically deformed, so that more liquefied vapor can be accommodated in the elastic bag layer.
[0013] Compared with the prior art, the beneficial effects achieved by the present invention are: By providing the pressure balancer, when the pressure in the inner tank is too high, a part of the liquefied gas will act on the piston plate through the through hole on the fixed plate, and the liquefied gas will push the piston plate to squeeze the elastic ring upward, so that the fixed plate is separated from the piston plate, and the liquefied gas flows upward through the concentrated flow of the concentrated flow cover, blowing the wind wheel to rotate around the fixed axis. When the wind wheel rotates, it hits the convex structure under the movable cover, so that the movable cover is compressed to the left by the impact force, and the spring is displaced. A section of the movable cover is removed from the through groove, and the liquefied gas enters the air flow channel therefrom, and then enters the elastic bag layer through the connecting pipe, so as to realize the pressure regulation inside the storage tank and prevent safety accidents. By providing the outer shell, the aerogel insulation layer, the vacuum insulation board layer, the glass fiber insulation layer, the diene elastic foam layer, the elastic bag layer, the LNG elastic felt layer, the polyurethane foam layer and the liner, the storage tank has good thermal insulation properties. At the same time, the diene elastic foam layer and the LNG elastic felt layer are elastic, providing the liquefied gas accommodating space for pressure regulation work, which is conducive to better pressure regulation work. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 is a cross-sectional view of the overall structure of an embodiment of the present invention; Figure 2 is an enlarged view of region A of an embodiment of the present invention; Figure 3 is a schematic diagram of the overall structure of a pressure balancer according to an embodiment of the present invention; Figure 4 Schematic diagram of the overall internal structure of the pressure balancer of an embodiment of the present invention Figure 5 is a schematic diagram of the operation of a pressure balancer according to an embodiment of the present invention; Figure 6 is a schematic diagram of a fixing plate and a piston plate of an embodiment of the present invention; Figure 7 is an enlarged view of region B of an embodiment of the present invention; In the figure: 1, tank shell; 2, pressure balancer; 3, fixed plate; 4, piston plate; 5, elastic ring; 6, flow collecting cover; 7, fixed shaft; 8, wind wheel; 9, upper cover; 10, blind groove; 101, through groove; 11, spring; 12, movable cover; 13, air flow channel; 131, connecting pipe; 14, outer shell; 15, aerogel insulation layer; 16, vacuum insulation board layer; 17, glass fiber insulation layer; 18, diene elastic foam layer; 19, elastic bag layer; 20, LNG elastic felt layer; 21, polyurethane foam layer; 22, liner; 23, cryogenic liquid; 24, liquefied gas; 25, first gas valve; 26, second gas valve; 27, liquid valve; 28, first gas passage; 29, second gas passage; 30, liquid passage. DETAILED DESCRIPTION
[0015] The following is a further non-limiting detailed description of the technical solution of the present invention in conjunction with the preferred embodiments and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0016] refer to Figure 1-Figure 7 , an embodiment of the present invention provides a medium-pressure cryogenic liquid storage tank, Figure 1 FIG. 2 is a cross-sectional view of the overall structure of an embodiment of the present invention, as shown in FIG. Figure 1 As shown, the medium-pressure cryogenic liquid storage tank comprises a storage tank shell 1, and a pressure balancer 2 is fixedly arranged above the interior of the storage tank shell 1. The pressure balancer 2 is used to balance the internal pressure of the storage tank shell 1, and the pressure balancer 2 is a hollow barrel-shaped structure. Figure 2As shown, a fixing plate 3 is welded to the lower end of the pressure balancer 2, a piston plate 4 is slidably arranged above the fixing plate 3 inside the pressure balancer 2, an elastic ring 5 is glued above the outer periphery of the piston plate 4, a flow collecting cover 6 is glued to the upper end of the elastic ring 5, and the outer side of the flow collecting cover 6 is glued to the inner wall of the tank shell 1, a fixing shaft 7 is fixedly arranged above the flow collecting cover 6 in the pressure balancer 2, a wind wheel 8 is sleeved on the middle section of the fixing shaft 7, the wind wheel 8 is located inside the pressure balancer 2, and an upper cover 9 is welded to the top of the pressure balancer 2.
[0017] like Figures 3 to 5 As shown, a through slot 101 is provided in the center of the upper cover 9, a blind slot 10 is provided on one side of the through slot 101 on the upper cover 9, a movable cover 12 is provided obliquely above the blind slot 10, the movable cover 12 completely covers the through slot 101 in the horizontal direction, and the length of the movable cover 12 is greater than the length of the through slot 101, so a part of the movable cover 12 extends out of the through slot 101 and overlaps the blind slot 10, a spring 11 is fixedly connected between the two opposite sides of the movable cover 12 and the blind slot 10, and a convex structure is provided at the lower end of the movable cover 12 to ensure that the wind wheel 8 is in a Figure 2 When the counterclockwise rotation occurs in the direction shown, the raised structure will be hit, so that the movable cover 12 is subjected to the impact force to compress the spring 11 to the left and move. A section of the movable cover 12 is removed from the through slot 101 for ventilation. An air flow channel 13 is also welded on the top of the upper cover 9. The area of the opening at the lower end of the air flow channel 13 completely covers the air flow channel 13, which is conducive to all the gas discharged from the through slot 101 entering the air flow channel 13.
[0018] like Figure 7 As shown, the outer wall of the storage tank shell 1 is composed of an outer shell 14, an aerogel insulation layer 15, a vacuum insulation board layer 16, a glass fiber insulation layer 17, a diene elastic foam layer 18, an elastic bag layer 19, an LNG elastic felt layer 20, a polyurethane foam layer 21 and an inner liner 22 from the outside to the inside. A connecting pipe 131 is also inserted above the air flow channel 13, and the connecting pipe 131 passes through the inner liner 22, the polyurethane foam layer 21 and the LNG elastic felt layer 20 to be connected to the elastic bag layer 19.
[0019] In certain preferred embodiments, Figure 6 As shown, a plurality of through holes are provided on the fixing plate 3, and a plurality of through holes are also provided on the piston plate 4, and the through holes on the fixing plate 3 are staggered with the through holes on the piston plate 4, which is beneficial for effectively blocking the airflow when the fixing plate 3 is in contact with the piston plate 4, and allowing the airflow to pass when the fixing plate 3 is separated from the piston plate 4.
[0020] In certain preferred embodiments, Figure 5As shown, the lower end of the focusing cover 6 is a circular plate with the same inner diameter as the pressure balancer 2. The outer side of the focusing cover 6 is tightly fitted to the inner wall of the pressure balancer 2 and glued to each other. A funnel-shaped opening design with a small top and a large bottom is provided in the center of the circular plate. The larger lower opening of the central funnel-shaped design is conducive to fully collecting the gas, and the smaller upper opening is conducive to gathering the collected gas and allowing it to flow out from the upper end, thereby obtaining greater wind force.
[0021] In certain preferred embodiments, Figure 1 As shown, the interior of the storage tank shell 1 stores cryogenic liquid 23, and the cryogenic liquid 23 does not completely fill the interior of the storage tank shell 1, thereby providing evaporation space for the cryogenic liquid 23 to prevent the cryogenic liquid 23 from evaporating due to the temperature rise, causing the pressure in the tank to increase greatly and cause danger. The cryogenic liquid 23 evaporates to form liquefied gas 24, and the liquefied gas 24 is located above the interior of the storage tank shell 1.
[0022] In some preferred embodiments, the elastic bag layer 19 is made of fluorosilicone rubber LS-2370U with a brittle temperature as low as -89°C. The fluorosilicone rubber LS-2370U can retain elasticity and air tightness even in a low temperature environment. The diene elastic foam layer 18 and the LNG elastic felt layer 20 located on both sides of the elastic bag layer 19 are elastic.
[0023] In certain preferred embodiments, Figure 1 As shown, the upper section of the storage tank shell 1 is provided with a first gas passage 28, and the first gas passage 28 is provided with a first gas valve 25. The first gas passage 28 completely penetrates from the outer shell 14 through all the insulation layers to the inside of the liner 22. The first gas passage 28 and the first gas valve 25 are conducive to the staff to adjust the first gas valve 25 to release the liquefied gas 24 to adjust the gas pressure in the tank. The middle section of the storage tank shell 1 is provided with a second gas passage 29, and the second gas passage 29 is provided with a second gas valve 26. The second gas passage 29 passes through the outer shell 14, the aerogel insulation layer 15, and the vacuum The insulation board layer 16, the glass fiber insulation layer 17 and the diene elastic foam layer 18 enter the interior of the elastic bag layer 19. The second gas passage 29 and the second gas valve 26 are beneficial for the staff to adjust the second gas valve 26 to release the liquefied gas 24 inside the elastic bag layer 19. The lower section of the storage tank shell 1 is provided with a liquid passage 30, and a liquid valve 27 is arranged on the liquid passage 30. The liquid passage 30 passes through all the insulation layers from the outer shell 14 and is connected to the interior of the inner liner 22. The liquid passage 30 and the liquid valve 27 are beneficial for the staff to inject or export the cryogenic liquid 23 into the interior of the storage tank shell 1.
[0024] In certain preferred embodiments, the aerogel insulation layer 15 is made of an organic-inorganic hybrid aerogel with a porosity of more than 90%. The organic-inorganic hybrid aerogel has good air tightness and low thermal conductivity, and the aerogel insulation layer 15 is tightly attached to the outside of the vacuum insulation board layer 16, which is beneficial for sealing the vacuum insulation board layer 16 when cracks appear in the outer shell 14 due to deterioration over time. It is also beneficial for assisting the sealing of the vacuum insulation board layer 16 before the staff finds that the outer shell 14 is damaged, thereby preventing the temperature in the pipe from rising rapidly and causing the cryogenic liquid 23 to evaporate rapidly.
[0025] In certain preferred embodiments, a method for adjusting the use of a medium-pressure cryogenic liquid storage tank of the present invention is as follows: When the outer shell 14 deteriorates and cracks appear, the vacuum degree of the vacuum insulation board layer 16 may be destroyed. At this time, the aerogel insulation layer 15 plays an auxiliary sealing role for the vacuum insulation board layer 16, reducing the evaporation rate of the cryogenic liquid 23. As the cryogenic liquid 23 evaporates, the liquefied vapor 24 increases, thereby increasing the pressure inside the liner 22. At this time, due to the increase in the pressure of the liquefied vapor 24 above the storage tank shell 1, a part of the liquefied vapor 24 will act on the piston plate 4 through the through holes on the fixed plate 3. Due to the increase in pressure, the liquefied vapor 24 pushes the piston plate 4 upward to squeeze the elastic ring 5. It is worth noting that in the pressure regulation work, the material selection and manufacturing of the elastic ring 5 must meet the requirements that when the upper pressure in the storage tank shell 1 exceeds the safety range, there will be enough pressure to squeeze and shorten the elastic ring 5 through the piston plate 4. Otherwise, it will not reach a sufficient pressure to cause elastic deformation of the elastic ring 5. The shortening of the elastic ring 5 separates the fixed plate 3 from the piston plate 4. Figure 5 As shown, the liquefied gas 24 flows upward through the through holes of the fixed plate 3 and the piston plate 4 in sequence. Through the focusing effect of the focusing cover 6, the liquefied gas 24 flowing upward blows the wind wheel 8 to rotate around the fixed axis 7. When the wind wheel 8 rotates, it hits the raised structure under the movable cover 12, so that the movable cover 12 is compressed to the left by the impact force and the spring 11 is displaced. A section of the movable cover 12 is removed from the through groove 101, and the liquefied gas 24 passes through the airflow channel 13, and then passes from the airflow channel 13 through the connecting pipe 131 into the elastic bag layer 19.
[0026] As the liquefied gas 24 continuously flows into the elastic bag layer 19, the diene elastic foam layer 18 and the LNG elastic felt layer 20 are squeezed and elastically deformed, so that the pressure in the elastic bag layer 19 is much smaller than the pressure in the inner liner 22. At the same time, due to the elastic contraction of the diene elastic foam layer 18 and the LNG elastic felt layer 20, more liquefied gas 24 can be accommodated until the pressure of the liquefied gas 24 above the storage tank shell 1 drops to a safe range, the elastic ring 5 stretches to drive the piston plate 4 to descend and fit closely with the fixed plate 3, the liquefied gas 24 is no longer conducted upward, the wind wheel 8 stops rotating, and the compression spring 11 naturally stretches to drive the movable cover 12 to completely cover the through groove 101 again, so as to realize the pressure regulation work inside the storage tank shell 1.
[0027] In some optional embodiments, a pressure detector and an alarm may also be provided on the storage tank shell 1. When the pressure detector detects that the pressure in the tank is too high, the alarm is sounded through the signal receiving alarm, so as to remind the staff to promptly inspect the storage tank shell 1 for damage and cracks to prevent the thermal insulation performance from deteriorating, and to make timely treatment. The first gas passage 28 and the second gas passage 29 are connected to an environment suitable for discharge, and the first gas valve 25 and the second gas valve 26 are adjusted to release the gas, so as to reduce the gas pressure in the tank to a safe state.
[0028] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.
[0029] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents, and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A medium-pressure cryogenic liquid storage tank, comprising a storage tank shell (1), characterized in that: A pressure balancer (2) is fixedly arranged above the inside of the storage tank shell (1). The pressure balancer (2) is a hollow barrel-shaped structure. A fixing plate (3) is welded to the lower end of the inside of the pressure balancer (2). A piston plate (4) is slidably arranged above the fixing plate (3) inside the pressure balancer (2). An elastic ring (5) is glued above the outer periphery of the piston plate (4). A flow collecting cover (6) is glued to the upper end of the elastic ring (5). A fixing shaft (7) is fixedly arranged above the flow collecting cover (6) inside the pressure balancer (2). A wind wheel (8) is sleeved on the middle section of the fixing shaft (7). The wind wheel (8) is located inside the pressure balancer (2). An upper cover (9) is welded to the top end of the pressure balancer (2). A through groove (101) is opened in the center of the upper cover (9). A blind groove (10) is provided on the upper cover (9) at one side of the through groove (101); a movable cover (12) is provided obliquely above the blind groove (10); the movable cover (12) completely covers the through groove (101) in the horizontal direction; a spring (11) is fixedly connected between two surfaces of the movable cover (12) opposite to the blind groove (10); a protruding structure is provided at the lower end of the movable cover (12) to ensure that the wind wheel (8) hits the protruding structure when rotating, so that the movable cover (12) is compressed to the left by the impact force and the spring (11) is displaced; a section of the movable cover (12) is moved away from the through groove (101) for ventilation; an air flow channel (13) is also welded above the upper cover (9); the area of the lower end opening of the air flow channel (13) completely covers the air flow channel (13); The outer wall of the storage tank shell (1) is composed of, from the outside to the inside, an outer shell (14), an aerogel insulation layer (15), a vacuum insulation board layer (16), a glass fiber insulation layer (17), a diene elastic foam layer (18), an elastic bag layer (19), an LNG elastic felt layer (20), a polyurethane foam layer (21) and an inner liner (22). A connecting pipe (131) is also inserted above the airflow channel (13), and the connecting pipe (131) passes through the inner liner (22), the polyurethane foam layer (21) and the LNG elastic felt layer (20) to be connected to the elastic bag layer (19).
2. A medium-pressure cryogenic liquid storage tank according to claim 1, characterized in that: The fixing plate (3) is provided with a plurality of through holes, and the piston plate (4) is also provided with a plurality of through holes, and the through holes on the fixing plate (3) and the through holes on the piston plate (4) are staggered.
3. A medium-pressure cryogenic liquid storage tank according to claim 2, characterized in that: The lower end of the focusing cover (6) is a circular plate having an inner diameter equal to that of the pressure balancer (2); the outer side of the focusing cover (6) is tightly attached to the inner wall of the pressure balancer (2) and is glued to each other; and a funnel-shaped opening design with a small top and a large bottom is provided in the center of the circular plate.
4. A medium-pressure cryogenic liquid storage tank according to claim 3, characterized in that: The storage tank shell (1) stores cryogenic liquid (23) inside, and the cryogenic liquid (23) does not completely fill the inside of the storage tank shell (1). The cryogenic liquid (23) evaporates to form liquefied gas (24), and the liquefied gas (24) is located above the inside of the storage tank shell (1).
5. A medium-pressure cryogenic liquid storage tank according to claim 4, characterized in that: The elastic bag layer (19) is made of fluorosilicone rubber LS-2370U with a brittle temperature as low as -89°C. The diene elastic foam layer (18) and the LNG elastic felt layer (20) located on both sides of the elastic bag layer (19) are elastic.
6. A medium-pressure cryogenic liquid storage tank according to claim 5, characterized in that: The upper section of the storage tank shell (1) is provided with a first gas passage (28), and a first gas valve (25) is provided on the first gas passage (28). The first gas passage (28) completely penetrates from the outer shell (14), penetrates all thermal insulation layers, and is connected to the interior of the liner (22). The first gas passage (28) and the first gas valve (25) facilitate a worker to adjust the first gas valve (25) to release the liquefied gas (24) to adjust the gas pressure in the tank. The middle section of the storage tank shell (1) is provided with a second gas passage (29), and a second gas valve (26) is provided on the second gas passage (29). The second gas passage (29) passes through the outer shell (14), the aerogel thermal insulation layer (15), and the vacuum thermal insulation board layer ( 16), the glass fiber insulation layer (17) and the diene elastic foam layer (18) enter the interior of the elastic bag layer (19), the second gas passage (29) and the second gas valve (26) facilitate the staff to adjust the second gas valve (26) to release the liquefied gas (24) inside the elastic bag layer (19), the lower section of the storage tank shell (1) is provided with a liquid passage (30), and the liquid passage (30) is provided with a liquid valve (27), the liquid passage (30) passes through all the insulation layers from the outer shell (14) and is connected to the interior of the liner (22), and the liquid passage (30) and the liquid valve (27) facilitate the staff to inject or discharge the cryogenic liquid (23) into the interior of the storage tank shell (1).
7. A medium-pressure cryogenic liquid storage tank according to claim 6, characterized in that: The aerogel thermal insulation layer (15) is made of organic-inorganic hybrid aerogel with a porosity of more than 90%, and the aerogel thermal insulation layer (15) is tightly attached to the outer side of the vacuum thermal insulation panel layer (16).
8. A method for using a medium-pressure cryogenic liquid storage tank, characterized in that: When the shell (14) deteriorates and cracks appear, the vacuum degree of the vacuum insulation board layer (16) may be destroyed, the insulation effect decreases, the cryogenic liquid (23) evaporates, the liquefied gas (24) increases, and the pressure inside the liner (22) increases. At this time, due to the increase in pressure, the pressure of the liquefied gas (24) above the storage tank shell (1) increases. Due to the increase in pressure, a part of the liquefied gas (24) will act on the piston plate (4) through the through hole on the fixing plate (3). Due to the increase in pressure, the liquefied gas (24) pushes the piston plate (4) upward to squeeze the elastic ring (5), so that the fixing plate (3) is separated from the piston plate (4). The liquefied gas (24) flows upward through the through holes of the fixing plate (3) and the piston plate (4) in turn, and passes through the converging cover (6). ) to blow the wind wheel (8) to rotate around the fixed shaft (7). When the wind wheel (8) rotates, it hits the raised structure below the movable cover (12), so that the movable cover (12) is compressed to the left by the impact force, causing the spring (11) to shift. A section of the movable cover (12) is removed from the through groove (101), and the liquefied gas (24) passes through the airflow channel (13) and then passes from the airflow channel (13) through the connecting pipe (131) into the elastic bag layer (19). As the liquefied gas (24) continues to pass into the elastic bag layer (19), the diene elastic foam layer (18) and the LNG elastic felt layer (20) are squeezed and elastically deformed, so that more liquefied gas (24) can be contained in the elastic bag layer (19).