CN110805827B

CN110805827B - Liquid gas storage tank with low-temperature coil protective layer and liquid storage method thereof

Info

Publication number: CN110805827B
Application number: CN201911183644.8A
Authority: CN
Inventors: 王栋
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-27
Filing date: 2019-11-27
Publication date: 2022-03-08
Anticipated expiration: 2039-11-27
Also published as: CN110805827A

Abstract

A liquid gas storage tank with a low-temperature coil protective layer relates to the technical field of gas storage tanks. It comprises a storage tank inner container; the outer wall of the storage tank; the low-temperature coil is assembled between the inner container of the storage tank and the outer wall of the storage tank and communicated with the top of the inner container of the storage tank; one end of the energy release device is communicated with the outlet of the low-temperature coil pipe, the other end of the energy release device is communicated with the bottom of the inner container of the storage tank, and the energy release device is used for reducing the heat of the gaseous gas; the pressure sensor and the valve are arranged on the low-temperature coil pipe; and a controller electrically connected to the pressure sensor and the valve, for controlling the valve to close when a detection value of the pressure sensor is higher than a set value and controlling the valve to open when the detection value of the pressure sensor is lower than the set value; and a vacuum layer is arranged between the inner container of the storage tank and the outer wall of the storage tank. Adopt above-mentioned technical scheme to have the advantage that reduces storage tank heat transfer efficiency and gas evaporation rate, ensure that the storage tank is stable, improved the save time of storage tank.

Description

Liquid gas storage tank with low-temperature coil protective layer and liquid storage method thereof

Technical Field

The invention relates to the technical field of gas storage tanks, in particular to a liquid gas storage tank with a low-temperature coil protective layer and a liquid storage method thereof.

Background

The stable energy supply is always an important support for the sustainable development of the modern society and is also a life pulse for the national development. Human beings have long used fossil fuels as the primary source of energy, but their inherent combustion products have posed catastrophic pollution problems. Today, where environmental hygiene is increasingly valued, it is a common general consensus among all people to control the emission of pollutants. Therefore, the application of green energy is put forward in a agenda, the hydrogen energy is considered as a real green energy because the hydrogen energy is discharged into water, and the storage and transportation of liquid hydrogen are important links for ensuring the utilization of the hydrogen energy.

However, the liquid hydrogen is evaporated and gasified due to the influence of the ambient temperature, and the heat is always transferred into the storage tank from the external environment because the ambient temperature is higher than the internal temperature of the storage tank, so that the liquid gas is gasified after being heated and expands, high pressure is formed in the storage tank, the safety of the storage tank is seriously threatened, the storage time and the transportation distance of the liquefied hydrogen are limited, and in order to avoid or reduce the gasification of the liquid hydrogen, the external heat is required to be reduced or delayed to enter the storage tank, and the heat transfer rate is required to be reduced. It is common practice to wrap the outer wall of the tank with insulation and maintain a vacuum layer. However, maintaining extremely low thermal conductivity may require very thick insulation layers, so that the tank becomes extremely bulky. It is not preferable in engineering and therefore improvements in liquefied gas storage tanks are needed.

Disclosure of Invention

The first objective of the present invention is to provide a liquid gas storage tank with a low-temperature coil protection layer, which has the advantages of reducing the heat transfer efficiency and the gas evaporation rate of the storage tank, ensuring the stability of the storage tank, and increasing the storage time of the storage tank, in view of the defects and disadvantages of the prior art.

In order to achieve the purpose, the invention adopts the technical scheme that: a liquid gas storage tank with a cryogenic coil protective layer, comprising: a storage tank inner container; the outer wall of the storage tank; the low-temperature coil is assembled between the inner container of the storage tank and the outer wall of the storage tank and communicated with the top of the inner container of the storage tank; one end of the energy release device is communicated with the outlet of the low-temperature coil pipe, the other end of the energy release device is communicated with the bottom of the inner container of the storage tank, and the energy release device is used for reducing the heat of the gaseous gas; the pressure sensor and the valve are arranged on the low-temperature coil pipe; and a controller electrically connected to the pressure sensor and the valve, for controlling the valve to close when a detection value of the pressure sensor is higher than a set value and controlling the valve to open when the detection value of the pressure sensor is lower than the set value; and a vacuum layer is arranged between the inner container of the storage tank and the outer wall of the storage tank.

The invention is further provided with a primary heat-insulating layer which is used for blocking heat transfer and keeping the inner container of the storage tank at a low temperature and is arranged outside the inner container of the storage tank; and the primary heat-insulating layer is filled with a heat-insulating material and is subjected to vacuum-pumping treatment.

According to the invention, a secondary insulating layer for blocking heat transfer and maintaining the temperature of the low-temperature coil pipe is arranged in the outer wall of the storage tank, and the secondary insulating layer is a vacuum cavity provided with an insulating material.

According to the invention, a gas collection chamber is arranged above the inner container of the storage tank.

According to the further arrangement of the invention, the low-temperature coil pipe is a thick-wall high-pressure low-temperature pipe.

In a further aspect of the invention, the energy release device comprises: the release valve body is communicated with the outlet of the low-temperature coil pipe and is used for allowing gaseous gas to enter the release device and primarily releasing energy of the gaseous gas; one end of the piston valve body is communicated with the release valve body and is used for secondarily releasing energy of the gaseous gas and realizing the static pressure balance of the gas in the release device; and the check valve body is communicated with the piston valve body at one end and the air inlet of the storage tank liner at the other end and is used for releasing the energy of the gaseous gas again and preventing the gaseous gas from flowing back.

The second purpose of the invention is to provide a liquid storage method for a liquid gas storage tank with a low-temperature coil protective layer, which is used for solving the problems that the liquid gas in the existing storage tank is easy to be gasified by heating and the storage and transportation time and distance are limited.

The above object of the present invention is achieved by the following technical solutions: a liquid storage method of a liquid gas storage tank with a low-temperature coil protection layer is based on the liquid gas storage tank with the low-temperature coil protection layer, and the method comprises the following steps:

s1, opening a valve at the upper part of the low-temperature coil pipe when canning, filling the low-temperature coil pipe with gas in the storage tank, and keeping the gaseous gas in the low-temperature coil pipe when canning is finished, wherein the temperature of the low-temperature coil pipe is the same as that in the storage tank;

s2, in the storage and transportation process, the temperature and the pressure of the gas in the low-temperature coil pipe gradually increase along with the heat transfer, when the temperature and the pressure are higher than the set value of the pressure sensor, the controller controls the valve on the upper part of the low-temperature coil pipe to be closed, the low-temperature coil pipe forms a closed space, the low-temperature coil pipe is composed of a thick-wall high-pressure pipe, so that the pressure of gasified gas can be borne, the low-temperature coil pipe forms an intermediate low-temperature layer, and the heat transfer into the inner container of the storage tank is blocked;

s3, transferring heat further, continuously increasing the temperature and pressure in the low-temperature coil, opening the energy release device at the bottom of the low-temperature coil when the pressure is higher than the set value of the energy release device, reducing the pressure and temperature when high-pressure gas passes through the device, and then introducing the high-pressure gas to the bottom of the inner container of the storage tank to be mixed with liquid gas in the tank, namely, the high-pressure gas is liquefied when encountering cold;

s4, because the gas in the low-temperature coil pipe is released and introduced into the storage tank, the pressure and the temperature in the low-temperature coil pipe are reduced, the low-temperature coil pipe can be further heated by external heat to wait for the next release;

s5, when the gas in the low-temperature coil is completely released, the controller controls the valve on the upper part of the low-temperature coil to be opened, and the gasified gas in the inner container of the storage tank is introduced to lower the temperature and the pressure of the low-temperature coil;

s6, repeating the process from S1 to S5, the heat is released properly, and the heat transferred into the inner container of the storage tank can be effectively reduced.

After the technical scheme is adopted, the invention has the beneficial effects that:

1. according to the liquid gas storage tank with the low-temperature coil protective layer, the low-temperature coil is arranged between the inner container of the storage tank and the outer wall of the storage tank, the single-layer heat transfer temperature difference between the external environment and the inner container of the storage tank is reduced by utilizing the low-temperature property of the gaseous gas, so that the heat transfer efficiency is reduced, partial heat energy is released through the energy release device, the pressure and the temperature of the gaseous gas are reduced, the heat transfer path is blocked, the heat transferred to the inner container of the storage tank is reduced, the gas evaporation rate is reduced, and the storage time of the storage tank is integrally prolonged.

2. According to the liquid storage method of the liquid gas storage tank with the low-temperature coil protective layer, the pressure sensor, the valve and the controller are used for controlling according to the dynamic air pressure in the low-temperature coil, when the air pressure in the low-temperature coil is higher than the set value of the pressure sensor, the controller controls the valve on the upper portion of the low-temperature coil to be closed, the low-temperature coil forms a closed space, the low-temperature coil forms a middle low-temperature layer, and heat is blocked from being transmitted into an inner container of the storage tank; when the gas quantity in the low-temperature coil is completely released, the controller controls the valve at the upper part of the low-temperature coil to be opened, and the gasified gas in the inner container of the storage tank is introduced again, so that the low-temperature coil is cooled and depressurized. The problem of liquid gas among the prior art be heated easily gasification, inflation, form high pressure in the storage tank, threat storage tank safety is effectively solved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the energy release apparatus of the present invention;

fig. 3 is another schematic view of the energy release device of the present invention.

Description of reference numerals: 1. a storage tank inner container; 2. the outer wall of the storage tank; 3. a low temperature coil; 4. an energy release device; 5. a pressure sensor; 6. a valve; 7. a vacuum layer; 11. a primary insulating layer; 21. a secondary insulating layer; 01. a gas collection chamber; 41. releasing the valve body; 42. a piston valve body; 43. a check valve body.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment as necessary without making a contribution thereto after reading the present specification, but all are protected by patent laws within the scope of the claims of the present invention.

The embodiment relates to a liquid gas storage tank with a low-temperature coil protective layer, as shown in fig. 1, comprising: a storage tank inner container 1; the outer wall 2 of the storage tank; the low-temperature coil pipe 3 is assembled between the inner container 1 of the storage tank and the outer wall 2 of the storage tank and communicated with the top of the inner container 1 of the storage tank; one end of the energy release device 4 is communicated with the outlet of the low-temperature coil 3, and the other end of the energy release device is communicated with the bottom of the inner container 1 of the storage tank and is used for reducing the heat of the gaseous gas; the pressure sensor 5 and the valve 6 are arranged on the low-temperature coil 3; and, the controller in connection with pressure sensor 5 and valve 6 electrically, when the detected value of pressure sensor 5 is lower than the set value, the controller control valve 6 opens, make gas full of in low temperature coil pipe 3, utilize the low temperature nature of gaseous gas itself, reduce the single-deck heat transfer temperature difference between external environment and storage tank inner bag 1, thereby reduce heat transfer efficiency, the heat that reaches storage tank inner bag 1 has been reduced, when the detected value of pressure sensor 5 is higher than the set value, controller control valve 6 closes, low temperature coil pipe 3 forms the middle low temperature layer of airtight space formation, thereby block thermal introduction storage tank inner bag 1, and then the storage time of storage tank has wholly been improved.

Wherein be vacuum layer 7 between storage tank inner bag 1 and the storage tank outer wall 2 for protect low temperature coil pipe 3, and reduce the heat transfer, 1 outside of storage tank inner bag is equipped with elementary heat preservation 11, and the intussuseption of elementary heat preservation 11 is filled with insulation material, and evacuation processing, be used for blocking heat transfer, keep 1 low temperature of storage tank inner bag. Inside second grade heat preservation 21 that is equipped with of storage tank outer wall 2, second grade heat preservation 21 is the vacuum cavity that is equipped with insulation material, be used for blocking heat transfer, keep low temperature coil pipe 3 temperature, vacuum layer 7 is located between primary heat preservation 11 and the second grade heat preservation 21, in this embodiment, low temperature coil pipe 3 is thick wall high pressure cryogenical tube, be used for providing low temperature environment for the storage tank, storage tank inner bag 1 comprises resistant cryogenic material, be used for storing liquid gas, storage tank outer wall 2 comprises insulation material and steel sheet, be used for supplying second grade heat preservation 21 to form, protection low temperature coil pipe 3.

As shown in fig. 1, the left side of fig. 1 is a sectional view of this embodiment, the right side is a schematic structural view, a low-temperature coil 3 is spirally wound between an inner tank 1 and an outer tank wall 2, an air collection chamber 01 is arranged at the top of the inner tank 1 for collecting gaseous gas in the inner tank 1, the low-temperature coil 3 is communicated with the air collection chamber 01, when the low-temperature coil 3 is filled with gaseous gas, the low-temperature property of the gaseous gas is utilized to reduce the single-layer heat transfer temperature difference between the external environment and the inner tank 1, thereby reducing the heat transfer efficiency and reducing the heat transferred to the inner tank 1, as the pressure and temperature in the low-temperature coil 3 rise, a controller controls a valve 6 to close to prevent the high-temperature gas in the low-temperature coil 3 from flowing to the inner tank 1, and the low-temperature coil 3 forms a closed space, the low-temperature coil 3 forms a middle low-temperature layer to block the heat transferred to the inner tank 1, and partial heat energy is released through the energy release device 4, so that the pressure of gaseous gas is reduced, the gas evaporation rate is reduced, a heat transfer path is blocked, and the heat transferred to the inner container 1 of the storage tank is reduced.

As shown in fig. 1 and 2, the energy release device 4 includes: the release valve body 41 is communicated with the outlet of the low-temperature coil 3 and is used for allowing gaseous gas to enter the release device and primarily releasing energy of the gaseous gas; a piston valve body 42, one end of which is communicated with the release valve body 41 and is used for secondarily releasing energy of the gaseous gas and realizing the static pressure balance of the gas in the release device; and a check valve body 43, one end of which is communicated with the piston valve body 42, the other end of which is communicated with the air inlet of the inner container 1 of the storage tank, and which is used for releasing the energy of the gaseous gas again and preventing the gaseous gas from flowing back. The gaseous gas is enabled to convert the energy (heat) of the gas into the potential energy of the spring in the process of overcoming the spring to do work, so that the pressure of the gaseous gas is reduced, the evaporation rate of the gas is reduced, and the storage time of the liquid gas is further prolonged.

As shown in fig. 2 and 3, the relief valve body 41 includes: releasing the valve body: the first release chamber is arranged in the release valve body, and one end of the first release chamber is provided with a gas inlet; a first compression chamber disposed within the relief valve body; a first valve shaft with one end slidably fitted in the first compression chamber and the other end inserted in the first release chamber; the first valve plate is arranged at one end of the first valve shaft and used for abutting against the gas inlet; and the first spring is arranged in the first compression chamber and abutted against the first valve shaft, when the pressure of the gas inlet is smaller than the set value of the first spring, the first spring drives the first valve plate to abut against the gas inlet, when the pressure of the gas inlet is larger than or equal to the set value of the first spring, the first valve plate is pushed by gaseous gas, and further the first spring is compressed to enable the first valve plate to be far away from the gas inlet, so that the gaseous gas is released in the first release chamber, meanwhile, in the process of pushing the first valve plate by the gaseous gas, the elastic force of the first spring needs to be overcome to do work, and further the potential energy of the gas is converted into the potential energy of the spring, so that the gaseous gas with the gas pressure of P0 is subjected to energy release to enable the pressure to be reduced to P1.

As shown in fig. 2 and 3, the piston valve body 42 includes: a piston valve body; a cylinder sleeve having one end connected to the first release chamber; a piston slidably mounted within the cylinder sleeve; and a second compression chamber provided in the piston valve body in a sliding direction of the piston; a plurality of vent holes communicated with the check valve body 43 are radially formed in the cylinder sleeve; the second compression chamber is internally provided with a second spring which is abutted against the piston, when the pressure in the first release chamber is smaller than the set value of the second spring, the second spring drives the piston to close the vent hole, when the pressure in the first release chamber is larger than or equal to the set value of the second spring, the piston is pushed by the gaseous gas in the first release chamber, so that the second spring is compressed, when the piston is continuously pushed and moves for a distance L, the vent hole is opened, at the moment, the second spring is compressed to the shortest distance, meanwhile, the gaseous gas needs to overcome the elastic force of the second spring to do work in the process of pushing the piston to move, so that the potential energy of the gas is further converted into the potential energy of the spring, and therefore, the gaseous gas with the gas pressure of P1 is subjected to energy release to reduce the pressure to P2, and then enters the check valve body 43 through the vent hole. It should be noted that, as shown in fig. 2, a gap is provided between the piston and the cylinder sleeve, and the gap is used for reducing the pressure of the gaseous gas in the first release chamber when the gas inlet is closed, the piston is reset under the action of the spring, and in the process, the gaseous gas in the first release chamber penetrates through the gap and enters the check valve body 43 through the vent hole to realize the static pressure balance of the gas in the release device.

As shown in fig. 2 and 3, the check valve body 43 includes: a check valve body; a third release chamber arranged in the check valve body, wherein one end of the third release chamber is connected with the vent hole, and the other end of the third release chamber is provided with a gas outlet; a third valve shaft with one end slidably fitted to the check valve body and the other end penetrating the third release chamber; the third valve plate is arranged at the end part of the third valve shaft and is abutted against one end, close to the vent hole, of the third release chamber; and the third spring is abutted between the side wall of the check valve body and the third valve plate, when the pressure at the vent hole is smaller than the set value of the third spring, the third spring drives the third valve plate to close the connecting channel between the third release chamber and the vent hole, when the pressure at the vent hole is larger than or equal to the set value of the third spring, the third valve plate is pushed by the gaseous gas at the vent hole, so that the third spring is compressed, the gaseous gas enters the third release chamber, meanwhile, the gaseous gas needs to overcome the elastic force of the third spring to do work in the process of pushing the third valve plate to move, and further the potential energy of the gas is converted into the potential energy of the spring, so that the gaseous gas with the gas pressure of P2 is subjected to energy release to reduce the pressure to P3, and then the gaseous gas is discharged into the storage tank inner container 1 from the gas outlet on the third release chamber.

Based on the above liquid gas storage tank with the low-temperature coil pipe 3 protection layer, the embodiment further relates to a liquid storage method of the liquid gas storage tank with the low-temperature coil pipe 3 protection layer, and the method includes:

s1, opening the valve 6 on the upper part of the low-temperature coil 3 when filling, filling the low-temperature coil 3 with gas in the storage tank, and keeping the gas in the low-temperature coil 3 when filling, wherein the temperature of the low-temperature coil 3 is the same as that in the storage tank;

s2, in the storage and transportation process, along with the heat transfer, the temperature and the pressure of the gas in the low-temperature coil 3 gradually increase, when the temperature and the pressure are higher than the set value of the pressure sensor 5, the controller controls the valve 6 at the upper part of the low-temperature coil 3 to be closed, the low-temperature coil 3 forms a closed space, as the low-temperature coil 3 consists of a thick-wall high-pressure pipe, the pressure of the gasified gas can be borne, the low-temperature coil 3 forms an intermediate low-temperature layer, and the heat transfer into the inner container 1 of the storage tank is blocked;

s3, transferring heat further, continuously increasing the temperature and pressure in the low-temperature coil 3, opening the energy release device at the bottom of the low-temperature coil 3 when the pressure is higher than the set value of the energy release device 4, reducing the pressure and temperature when high-pressure gas passes through the device, and then introducing the high-pressure gas into the bottom of the inner container 1 of the storage tank to be mixed with liquid gas in the tank, namely, the high-pressure gas is liquefied when meeting cold;

s4, because the gas in the low-temperature coil 3 is released and introduced into the storage tank, the pressure and the temperature in the low-temperature coil 3 are reduced, and the low-temperature coil can be further heated by external heat to wait for the next release;

s5, when the gas quantity in the low-temperature coil 3 is completely released, the controller controls the valve 6 on the upper part of the low-temperature coil 3 to be opened, and the gasified gas in the inner container 1 of the storage tank is introduced, so that the low-temperature coil 3 is cooled and depressurized;

s6, repeating the process from S1 to S5, the heat is released properly, and the heat transferred into the tank liner 1 can be effectively reduced.

The working principle of the invention is roughly as follows: through set up low temperature coil pipe 3 between storage tank inner bag 1 and storage tank outer wall 2, utilize the low temperature nature of gaseous state gas itself, reduce the individual layer heat transfer difference in temperature between external environment and the storage tank inner bag 1, thereby reduce heat transfer efficiency, rethread energy release 4 is to release partial heat energy, reduce gaseous state gas's pressure, with reduction gas evaporation rate, block the heat transfer way, reduced the heat that passes to storage tank inner bag 1, and then whole save time who has improved the storage tank. The pressure sensor 5, the valve 6 and the controller are used for controlling according to the dynamic air pressure in the low-temperature coil 3, when the air pressure in the low-temperature coil 3 is higher than the set value of the pressure sensor 5, the controller controls the valve 6 on the upper part of the low-temperature coil 3 to be closed, the low-temperature coil 3 forms a closed space, the low-temperature coil 3 forms a middle low-temperature layer, and heat is blocked from being transmitted into the inner container 1 of the storage tank; when the amount of gas in the low-temperature coil 3 is completely released, the controller controls the valve 6 on the upper part of the low-temperature coil 3 to be opened, and the gasified gas in the inner container 1 of the storage tank is introduced again, so that the low-temperature coil 3 is cooled and depressurized. The problem of liquid gas among the prior art be heated easily gasification, inflation, form high pressure in the storage tank, threat storage tank safety is effectively solved.

The above description is only for the purpose of illustrating the technical solutions of the present invention and not for the purpose of limiting the same, and other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention should be covered by the claims of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A liquid gas storage tank with a low-temperature coil protective layer is characterized by comprising: a tank inner container (1);

an outer tank wall (2);

the low-temperature coil (3) is assembled between the storage tank inner container (1) and the storage tank outer wall (2) and communicated with the top of the storage tank inner container (1); and the number of the first and second groups,

the energy release device (4) is communicated with the outlet of the low-temperature coil (3) at one end and the bottom of the storage tank liner (1) at the other end and is used for reducing the heat of the gaseous gas;

the pressure sensor (5) and the valve (6) are arranged on the low-temperature coil (3); and the number of the first and second groups,

a controller electrically connected to the pressure sensor (5) and the valve (6) and controlling the valve (6) to close when the detection value of the pressure sensor (5) is higher than a set value and controlling the valve (6) to open when the detection value of the pressure sensor (5) is lower than the set value;

a vacuum layer (7) is arranged between the inner container (1) of the storage tank and the outer wall (2) of the storage tank;

the energy release device (4) comprises: the release valve body (41) is communicated with the outlet of the low-temperature coil (3) and is used for allowing gaseous gas to enter the release device and primarily releasing energy of the gaseous gas;

one end of the piston valve body (42) is communicated with the release valve body (41) and is used for secondarily releasing energy of the gaseous gas and realizing the static pressure balance of the gas in the release device; and the number of the first and second groups,

the check valve body (43) is communicated with the piston valve body (42) at one end and is communicated with the air inlet of the storage tank liner (1) at the other end and is used for releasing the energy of the gaseous gas again and preventing the gaseous gas from flowing back;

the release valve body (41) includes: releasing the valve body: the first release chamber is arranged in the release valve body, and one end of the first release chamber is provided with a gas inlet; a first compression chamber disposed within the relief valve body; a first valve shaft with one end slidably fitted in the first compression chamber and the other end inserted in the first release chamber; the first valve plate is arranged at one end of the first valve shaft and used for abutting against the gas inlet; and a first spring disposed in the first compression chamber and abutting against the first valve shaft;

the piston valve body (42) includes: a piston valve body; a cylinder sleeve having one end connected to the first release chamber; a piston slidably mounted within the cylinder sleeve; and a second compression chamber provided in the piston valve body in a sliding direction of the piston; a plurality of vent holes communicated with the check valve body (43) are formed in the radial direction of the cylinder sleeve; a second spring abutting against the piston is arranged in the second compression chamber;

the check valve body (43) comprises: a check valve body; a third release chamber arranged in the check valve body, wherein one end of the third release chamber is connected with the vent hole, and the other end of the third release chamber is provided with a gas outlet; a third valve shaft with one end slidably fitted to the check valve body and the other end inserted into the third release chamber; the third valve plate is arranged at the end part of the third valve shaft and is abutted against one end, close to the vent hole, of the third release chamber; and a third spring abutting between the side wall of the check valve body and the third valve plate.

2. The liquid gas storage tank with the low-temperature coil protection layer as claimed in claim 1, wherein a primary insulating layer (11) for blocking heat transfer and maintaining low temperature of the storage tank liner (1) is arranged outside the storage tank liner (1);

and the primary heat-insulating layer (11) is filled with heat-insulating materials and is subjected to vacuum-pumping treatment.

3. The liquid gas storage tank with the low-temperature coil protection layer as claimed in claim 1, wherein a secondary insulation layer (21) for blocking heat transfer and maintaining the temperature of the low-temperature coil (3) is arranged inside the outer wall (2) of the storage tank, and the secondary insulation layer (21) is a vacuum cavity provided with insulation materials.

4. The liquid gas storage tank with the low-temperature coil protection layer as claimed in claim 1, wherein a gas collection chamber (01) is arranged above the storage tank liner (1).

5. Liquid gas storage tank with cryogenic coil protection according to claim 1, characterized in that the cryogenic coil (3) is a thick-walled high-pressure cryogenic pipe.

6. A method of storing liquid gas storage tank with cryogenic coil protection, the method being based on any one of claims 1-5, the method comprising:

s1, opening a valve (6) at the upper part of the low-temperature coil (3) during canning, filling the low-temperature coil (3) with gas in the storage tank, and keeping the gaseous gas in the low-temperature coil (3) when canning is finished, wherein the temperature of the low-temperature coil (3) is the same as that in the storage tank;

s2, in the storage and transportation process, along with the heat transfer, the temperature and the pressure of the gas in the low-temperature coil (3) are gradually increased, when the temperature and the pressure are higher than the set value of the pressure sensor (5), the controller controls the valve (6) at the upper part of the low-temperature coil (3) to be closed, the low-temperature coil (3) forms a closed space, the low-temperature coil (3) consists of a thick-wall high-pressure pipe, so that the pressure of gasified gas can be borne, the low-temperature coil (3) forms an intermediate low-temperature layer, and the heat transfer into the inner container (1) of the storage tank is blocked;

s3, transferring heat further, continuously increasing the temperature and pressure in the low-temperature coil (3), opening the energy release device at the bottom of the low-temperature coil (3) when the pressure is higher than the set value of the energy release device (4), reducing the pressure and temperature of high-pressure gas passing through the device, and then introducing the high-pressure gas into the bottom of the inner container (1) of the storage tank to mix with liquid gas in the tank, namely, the high-pressure gas is liquefied when meeting cold;

s4, because the gas in the low-temperature coil (3) is released and introduced into the storage tank, the pressure and the temperature in the low-temperature coil (3) are reduced, and the low-temperature coil can be further heated by external heat for waiting for the next release;

s5, when the gas in the low-temperature coil (3) is completely released, the controller controls the valve (6) at the upper part of the low-temperature coil (3) to be opened, and the gasified gas in the inner container (1) of the storage tank is introduced to lower the temperature and reduce the pressure of the low-temperature coil (3);

s6, repeating the process from S1 to S5, the heat is released properly, and the heat transferred into the inner container (1) of the storage tank can be effectively reduced.