CN116697268A

CN116697268A - Hydrogen pressure release system and liquid hydrogen transport tank car

Info

Publication number: CN116697268A
Application number: CN202310545384.4A
Authority: CN
Inventors: 邱小林; 雷刚; 王天祥; 邱一男; 吕云; 徐元元; 王义伟; 田歌
Original assignee: 63921 Troops of PLA
Current assignee: 63921 Troops of PLA
Priority date: 2023-05-15
Filing date: 2023-05-15
Publication date: 2023-09-05

Abstract

The invention relates to the technical field of liquid hydrogen storage and transportation, in particular to a hydrogen pressure relief system and a liquid hydrogen transportation tank car. The hydrogen pressure relief system includes: a storage tank, on which a first hydrogen pipe is connected; the first pressure relief unit is connected with the first hydrogen pipeline through a first pressure relief main path; the first pressure relief unit comprises a first low-pressure relief branch and a second low-pressure relief branch which are arranged in parallel; the first pressure regulating valve is arranged on the first low-pressure relief branch; the second pressure regulating valve is arranged on the second low-pressure relief branch; the release pressure of the first pressure regulating valve and/or the second pressure regulating valve is P1, the real-time pressure in the storage tank is Pt, and when Pt is more than or equal to P1, the first pressure regulating valve and/or the second pressure regulating valve is opened to release pressure in the storage tank. The hydrogen pressure relief system provided by the invention can adapt to different transportation working conditions, and meanwhile, the problem that the safety valve must be checked again after one trip is avoided.

Description

Hydrogen pressure release system and liquid hydrogen transport tank car

Technical Field

The invention relates to the technical field of liquid hydrogen storage and transportation, in particular to a hydrogen pressure relief system and a liquid hydrogen transportation tank car.

Background

The liquid hydrogen is a dangerous article which is deep low-temperature, inflammable and explosive, and the liquid hydrogen is vaporized and expanded along with the heat absorption from the outside in the transportation process, the volume is gradually increased, the pressure in the vehicle-mounted storage tank is gradually increased, the speed is higher and higher along with the time, if the pressure is not released in time, the liquid in the tank is easily caused to rapidly expand, the gas phase space is rapidly reduced, the pressure in the tank is rapidly increased, and the whole tank body is filled with the liquid, so that the potential safety hazard is greatly brought.

The existing hydrogen pressure relief system is applied to road transportation working conditions by arranging a first safety valve and a second safety valve and connecting the first safety valve and the second safety valve in parallel as shown in the publication No. CN 102954346B. However, for road transportation working conditions, on one hand, the set pressure of the safety valve needs to be matched with the working pressure, and the adapted transportation working conditions are single, so that the safety valve cannot meet various working conditions caused by different working pressures and loading amounts in the actual transportation process; on the other hand, the safety valve is not only meant to be in a safety accident after taking off, but also needs to be checked again after taking off once, and the safety valve needs to be disassembled and sent to a professional institution for rechecking when being checked.

Therefore, the existing hydrogen pressure relief system is single in transportation working condition due to the fact that the safety valve is arranged to relieve pressure, and the safety valve needs to be checked again after one trip, so that the hydrogen pressure relief system which can adapt to different transportation working conditions and meanwhile avoids the fact that the safety valve needs to be checked again after one trip is needed.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defects that the existing hydrogen pressure relief system is single in transportation working condition adapted to pressure relief by arranging the safety valve and the safety valve must be checked again after one time of taking off, so as to provide the hydrogen pressure relief system which can adapt to different transportation working conditions and simultaneously avoid the situation that the safety valve must be checked again after one time of taking off and the liquid hydrogen transportation tank car with the same.

In order to solve the above technical problems, the hydrogen pressure relief system provided by the present invention includes:

a storage tank, on which a first hydrogen pipe is connected;

the first pressure relief unit is connected with the first hydrogen pipeline through a first pressure relief main path; the first pressure relief unit comprises a first low-pressure relief branch and a second low-pressure relief branch which are arranged in parallel; the air inlet end of the first low-pressure relief branch and the air inlet end of the second low-pressure relief branch are connected with the first pressure relief main path, and the air outlet end of the first low-pressure relief branch and the air outlet end of the second low-pressure relief branch are connected with a first flame arrester;

the first pressure regulating valve is arranged on the first low-pressure relief branch;

the second pressure regulating valve is arranged on the second low-pressure relief branch;

the release pressure of the first pressure regulating valve and/or the second pressure regulating valve is P1, the real-time pressure in the storage tank is Pt, and when Pt is more than or equal to P1, the first pressure regulating valve and/or the second pressure regulating valve is opened to release pressure in the storage tank.

Optionally, a first stop valve is further arranged on the first low-pressure relief branch, one end of the first stop valve is connected with the first pressure regulating valve, and the other end of the first stop valve is suitable for being connected with the first pressure relief main path;

and a second stop valve is further arranged on the second low-pressure relief branch, one end of the second stop valve is connected with the second pressure regulating valve, and the other end of the second stop valve is suitable for being connected with the first pressure relief main path.

Optionally, a third stop valve is disposed on the first pressure relief main path, an inlet of the third stop valve is connected with the first pressure relief main path, and an outlet of the third stop valve connects the first low pressure relief branch and the second low pressure relief branch in parallel.

Optionally, the hydrogen pressure relief system further comprises a second pressure relief unit, and the second pressure relief unit is connected with the first hydrogen pipeline through a second pressure relief main path;

the second pressure relief unit comprises a first high-pressure relief branch and a second high-pressure relief branch which are arranged in parallel, the air inlet end of the first high-pressure relief branch and the air inlet end of the second high-pressure relief branch are connected with the second pressure relief main path, and the air outlet end of the first high-pressure relief branch and the air outlet end of the second high-pressure relief branch are connected with a second flame arrester;

the first high-pressure relief branch is provided with a first safety valve, the second high-pressure relief branch is provided with a second safety valve, and the tripping pressure of the first safety valve and/or the second safety valve is P2, wherein P2 is more than P1; when Pt is more than or equal to P2, the first safety valve and/or the second safety valve are/is opened to release pressure in the storage tank.

Optionally, the second pressure relief unit further includes a third high-pressure relief branch and a fourth high-pressure relief branch which are arranged in parallel, an air inlet end of the third high-pressure relief branch and an air inlet end of the fourth high-pressure relief branch are connected with the second pressure relief main path, and an air outlet end of the third high-pressure relief branch and an air outlet end of the fourth high-pressure relief branch are connected with a third flame arrester;

the third high-pressure relief branch is provided with a first rupture disk, the fourth high-pressure relief branch is provided with a second rupture disk, and the explosion critical pressure of the first rupture disk and/or the second rupture disk is P3, wherein P3 is more than P2; and when Pt is more than or equal to P3, the first rupture disk and/or the second rupture disk are blasted to release pressure in the storage tank.

Optionally, a first three-way valve is arranged on the second pressure relief main path, an inlet of the first three-way valve is connected with the second pressure relief main path, a first outlet of the first three-way valve is simultaneously connected with the first high-pressure relief branch and the third high-pressure relief branch in parallel, and a second outlet of the first three-way valve is simultaneously connected with the second high-pressure relief branch and the fourth high-pressure relief branch in parallel.

Optionally, a second hydrogen pipeline is also connected to the storage tank; the hydrogen pressure relief system further includes a third pressure relief unit, the third pressure relief unit including:

a safety hydrogen discharger;

the first port of the temperature return device is connected with the first hydrogen pipeline through a third pressure relief main path, and the second port of the temperature return device is simultaneously connected with the safe hydrogen discharger and the second hydrogen pipeline;

and the fourth stop valve is arranged on the third pressure relief main circuit and is suitable for selectively communicating the first hydrogen pipeline with the temperature return device.

Optionally, the third pressure relief unit further includes:

the inlet of the second three-way valve is connected with the second port of the thermostat, the first outlet of the second three-way valve is connected with the safety hydrogen discharger, and the second outlet of the second three-way valve, the exhaust end of the first low-pressure relief branch and the exhaust end of the second low-pressure relief branch are simultaneously connected with the first flame arrester;

the one-way valve is arranged between the second three-way valve and the temperature return device;

and the fifth stop valve is arranged between the temperature return device and the one-way valve and is suitable for selectively communicating the temperature return device with the safety hydrogen discharger.

Optionally, a sixth stop valve is further arranged on the first low-pressure relief branch and/or the second low-pressure relief branch, and the sixth stop valve is in a normally closed state;

the first high-pressure relief branch, the second high-pressure relief branch, the third high-pressure relief branch and/or the fourth high-pressure relief branch are/is further provided with a seventh stop valve, and the seventh stop valve is in a normally closed state.

The invention also provides a liquid hydrogen transport tank car, comprising: tank car body, and hydrogen pressure release system as described above.

The technical scheme of the invention has the following advantages:

1. according to the hydrogen pressure relief system provided by the invention, the first pressure relief unit comprises a first low-pressure relief branch and a second low-pressure relief branch which are arranged in parallel, a first pressure regulating valve is arranged on the first low-pressure relief branch, a second pressure regulating valve is arranged on the second low-pressure relief branch, the release pressure value of the first pressure regulating valve and/or the second pressure regulating valve is set to be P1, when the real-time pressure Pt in the storage tank is more than or equal to P1, the first pressure regulating valve and/or the second pressure regulating valve is automatically opened, so that the interior of the storage tank is relieved, and when Pt is less than P1, the first pressure regulating valve and the second pressure regulating valve are automatically closed, so that the exhaust is stopped; by setting the release pressure of the first pressure regulating valve and/or the second pressure regulating valve according to different transportation working conditions, the situation that the safety valve must be checked again after one trip is avoided, and therefore the actual safety transportation requirements under different transportation working conditions are met.

2. In the hydrogen pressure relief system provided by the invention, in the process of exhausting the first pressure regulating valve and the second pressure regulating valve, if the pressure and the liquid level in the storage tank continuously rise abnormally, when the liquid level is close to completely filling the gas space in the storage tank, the pressure in the storage tank rises rapidly, when Pt is more than or equal to P2, the tripping pressures of the first safety valve and the second safety valve are triggered, the first safety valve and the second safety valve are opened, and the hydrogen in the storage tank is subjected to air exhaust and pressure relief through the first pressure relief unit and the second pressure relief unit at the same time, so that the hydrogen pressure relief system is suitable for more complicated transportation working conditions and meets the actual safety transportation requirements under different transportation working conditions.

3. According to the hydrogen pressure relief system provided by the invention, after the first safety valve and the second safety valve are opened, if the pressure in the storage tank continuously and abnormally rises, when Pt is more than or equal to P3, the explosion critical pressure values of the first rupture disk and the second rupture disk are triggered, the first rupture disk and the second rupture disk are exploded, and the first rupture disk, the second safety valve, the first pressure regulating valve and the second pressure regulating valve are simultaneously opened for exhausting and relieving pressure, so that the safety of the storage tank is ensured under more complicated and severe transportation conditions, and the actual safety transportation requirements under different transportation conditions are further met.

4. According to the hydrogen pressure relief system provided by the invention, the temperature return device is arranged, so that the first port of the temperature return device is connected with the first hydrogen pipeline through the third pressure relief main circuit, and the second port of the temperature return device is connected with the safety hydrogen discharge device and the second hydrogen pipeline at the same time, so that low-temperature hydrogen in the storage tank can be subjected to heat exchange with the atmosphere to be heated to normal-temperature hydrogen after passing through the temperature return device, the low-temperature hydrogen is not only prevented from being condensed into ice when discharged, the discharge port is prevented from being blocked, but also the hydrogen concentration is reduced by heating, and the potential safety hazard caused by overhigh short-time hydrogen concentration is avoided.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the operation of the hydrogen pressure relief system of the present invention;

fig. 2 is a schematic diagram illustrating the working principle of a first pressure relief unit of the hydrogen pressure relief system in fig. 1;

fig. 3 is a schematic diagram illustrating the working principle of a second pressure relief unit of the hydrogen pressure relief system in fig. 1;

fig. 4 is a schematic diagram illustrating the operation of a third pressure relief unit of the hydrogen pressure relief system in fig. 1;

FIG. 5 is a schematic diagram of the purge replacement principle of the first pressure relief unit of the hydrogen pressure relief system of FIG. 1;

fig. 6 is a schematic diagram of the purge replacement principle of the second pressure relief unit of the hydrogen pressure relief system in fig. 1.

Reference numerals illustrate:

1. a storage tank; 11. a first hydrogen conduit; 12. a second hydrogen conduit;

2. a first pressure relief unit; 20. a first pressure relief main path; 201. a third stop valve; 202. a first flame arrestor; 21. a first low pressure relief branch; 211. a first pressure regulating valve; 212. a first stop valve; 22. the second low-pressure relief branch circuit; 221. a second pressure regulating valve; 222. a second shut-off valve;

3. a second pressure relief unit; 30. a second pressure relief main path; 301. a first three-way valve; 302. a second flame arrestor; 303. a third flame arrestor; 31. a first high pressure relief branch; 311. a first safety valve; 32. the second high-pressure relief branch circuit; 321. a second safety valve; 33. a third high pressure relief branch; 331. a first rupture disk; 34. a fourth high pressure relief branch; 341. a second rupture disk;

4. a third pressure relief unit; 40. a third pressure relief main path; 401. a fourth shut-off valve; 41. a safety hydrogen discharger; 42. a temperature returning device; 43. a second three-way valve; 44. a one-way valve; 45. a fifth shut-off valve;

51. a sixth shut-off valve; 52. and a seventh stop valve.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

Example 1

Referring to fig. 1 to fig. 4, the hydrogen pressure relief system provided in this embodiment includes:

a storage tank 1 to which a first hydrogen pipe 11 is connected;

the first pressure relief unit 2 is connected with the first hydrogen pipeline 11 through a first pressure relief main path 20; the first pressure relief unit 2 comprises a first low pressure relief branch 21 and a second low pressure relief branch 22 which are arranged in parallel; the air inlet end of the first low pressure relief branch 21 and the air inlet end of the second low pressure relief branch 22 are connected with the first pressure relief main path 20, and the air outlet end of the first low pressure relief branch 21 and the air outlet end of the second low pressure relief branch 22 are connected with the first flame arrestor 202;

a first pressure regulating valve 211 disposed on the first low pressure relief branch 21;

a second pressure regulating valve 221 disposed on the second low pressure relief branch 22;

the release pressure of the first pressure regulating valve 211 and/or the second pressure regulating valve 221 is P1, the real-time pressure in the storage tank 1 is Pt, and when Pt is greater than or equal to P1, the first pressure regulating valve 211 and/or the second pressure regulating valve 221 is opened to release the pressure in the storage tank 1.

It should be noted that, after the first pressure regulating valve 211 and/or the second pressure regulating valve 221 are installed, the release pressure value is set, and then the automatic operation can be put into operation, the release pressure of the first pressure regulating valve 211 and/or the second pressure regulating valve 221 can be set for different transportation working conditions, and the release pressure of the first pressure regulating valve 211 and/or the second pressure regulating valve 221 can be regulated according to the working pressure Pt of different storage tanks, so as to adapt to various working conditions caused by different working pressures and loading amounts in the actual transportation process, and the automatic operation can be realized without re-checking when resetting, so that different transportation working conditions are adapted, and the need of re-checking after the safety valve is tripped once is avoided.

Optionally, the first pressure regulating valve 211 and/or the second pressure regulating valve 221 are self-operated pressure regulating valves.

It should be noted that, the first pressure relief unit 2 is a low pressure relief unit, and the first pressure relief unit 2 is adapted to relieve pressure under a normal transportation condition; when the pressure in the storage tank 1 is in a micro-pressure state during the full-load liquid hydrogen transportation of the liquid hydrogen transportation vehicle, as shown in fig. 1 and 2, during the process, the third stop valve 201 is in an open state, the first pressure regulating valve 211 and the second pressure regulating valve 221 are both in an operating state, during the long-distance normal transportation, when the pressure in the storage tank 1 rises to 95% of the liquid level due to heat absorption from the outside, the real-time pressure Pt in the storage tank 1 is more than or equal to P1, at the moment, the first pressure regulating valve 211 and the second pressure regulating valve 221 are opened, so that the hydrogen is discharged to the outside through the first flame arrestor 202 to decompress the inside of the storage tank 1, and after decompression, the pressure in the storage tank 1 is reduced until Pt < P1, at the moment, the first pressure regulating valve 211 and the second pressure regulating valve 221 are closed, and the exhaust is stopped, thereby ensuring that the liquid level in the storage tank 1 is at most not more than 98%.

In this embodiment, the first pressure relief unit 2 includes a first low pressure relief branch 21 and a second low pressure relief branch 22 that are disposed in parallel, and by disposing a first pressure regulating valve 211 on the first low pressure relief branch 21 and disposing a second pressure regulating valve 221 on the second low pressure relief branch 22, and setting a relief pressure value of the first pressure regulating valve 211 and/or the second pressure regulating valve 221 to be P1, when a real-time pressure Pt in the storage tank 1 is greater than or equal to P1, the first pressure regulating valve 211 and/or the second pressure regulating valve 221 is automatically opened, so as to relieve pressure in the storage tank 1, and when Pt is less than P1, the first pressure regulating valve 211 and the second pressure regulating valve 221 are automatically closed, so as to stop exhausting; by setting the release pressure of the first pressure regulating valve 211 and/or the second pressure regulating valve 221 for different transportation conditions, the need for rechecking after one trip of the safety valve is avoided, thereby adapting to the actual safety transportation requirements under different transportation conditions.

Specifically, the first low pressure relief branch 21 is further provided with a first stop valve 212, one end of the first stop valve 212 is connected with the first pressure regulating valve 211, and the other end is adapted to be connected with the first pressure relief main path 20;

the second low pressure relief branch 22 is further provided with a second stop valve 222, one end of the second stop valve 222 is connected with the second pressure regulating valve 221, and the other end is adapted to be connected with the first pressure relief main circuit 20.

It should be noted that, referring to fig. 1 and 2, one end of the first stop valve 212 is connected to the first pressure regulating valve 211, the other end is adapted to be connected to the first pressure relief main path 20, one end of the second stop valve 222 is connected to the second pressure regulating valve 221, and the other end is adapted to be connected to the first pressure relief main path 20, by providing the first stop valve 212 and the second stop valve 222, when the first pressure regulating valve 211 is maintained and/or replaced, the first stop valve 212 may be closed, and when the second pressure regulating valve 221 is maintained and/or replaced, the second stop valve 222 may be closed, thereby avoiding hydrogen leakage during maintenance and/or replacement, and ensuring safety of maintenance and/or replacement operations.

Specifically, a third stop valve 201 is disposed on the first pressure relief main path 20, an inlet of the third stop valve 201 is connected with the first pressure relief main path 20, and an outlet of the third stop valve 201 connects the first low pressure relief branch 21 and the second low pressure relief branch 22 in parallel.

During the full-load liquid hydrogen transportation of the liquid hydrogen transportation vehicle, the third stop valve 201 is in an open state, and the first stop valve 212 and the second stop valve 222 are both in an open state.

Specifically, the hydrogen pressure relief system further includes a second pressure relief unit 3, and the second pressure relief unit 3 is connected to the first hydrogen pipeline 11 through a second pressure relief main path 30;

the second pressure relief unit 3 includes a first high-pressure relief branch 31 and a second high-pressure relief branch 32 which are arranged in parallel, an air inlet end of the first high-pressure relief branch 31 and an air inlet end of the second high-pressure relief branch 32 are both connected with the second pressure relief main path 30, and an air outlet end of the first high-pressure relief branch 31 and an air outlet end of the second high-pressure relief branch 32 are both connected with the second flame arrester 302;

the first high-pressure relief branch 31 is provided with a first safety valve 311, the second high-pressure relief branch 32 is provided with a second safety valve 321, and the tripping pressure of the first safety valve 311 and/or the second safety valve 321 is P2, wherein P2 is more than P1; when Pt is more than or equal to P2, the first safety valve 311 and/or the second safety valve 321 are/is opened to release the pressure inside the storage tank 1.

It should be noted that the second pressure relief unit 3 is a high-pressure relief unit, and the second pressure relief unit 3 is adapted to perform pressure relief under an accident condition; referring to fig. 1-3, in the process of fully transporting liquid hydrogen in the liquid hydrogen transporting vehicle, during the process of exhausting the first pressure regulating valve 211 and the second pressure regulating valve 221, if the pressure and the liquid level in the storage tank 1 continue to rise abnormally, when the liquid level is nearly completely full of the gas space in the storage tank 1, the pressure in the storage tank 1 rises rapidly, and when Pt is greater than or equal to P2, the take-off pressures of the first safety valve 311 and the second safety valve 321 are triggered, the first safety valve 311 and the second safety valve 321 are opened, and the hydrogen in the storage tank 1 is exhausted and decompressed simultaneously via the first decompression unit 2 and the second decompression unit 3, so that more complex transportation conditions are adapted, and the actual safe transportation requirements under different transportation conditions are satisfied.

Specifically, the second pressure relief unit 3 further includes a third high-pressure relief branch 33 and a fourth high-pressure relief branch 34 that are disposed in parallel, an air inlet end of the third high-pressure relief branch 33 and an air inlet end of the fourth high-pressure relief branch 34 are both connected with the second pressure relief main path 30, and an air outlet end of the third high-pressure relief branch 33 and an air outlet end of the fourth high-pressure relief branch 34 are both connected with the third flame arrestor 303;

the third high-pressure relief branch 33 is provided with a first rupture disk 331, the fourth high-pressure relief branch 34 is provided with a second rupture disk 341, and the explosion critical pressure of the first rupture disk 331 and/or the second rupture disk 341 is P3, wherein P3 is greater than P2; when Pt is more than or equal to P3, the first rupture disk 331 and/or the second rupture disk 341 are ruptured to release the pressure inside the storage tank 1.

It should be noted that, referring to fig. 1-3, in the process of fully transporting liquid hydrogen in the liquid hydrogen transporting vehicle, if the pressure in the storage tank 1 continues to rise abnormally after the first safety valve 311 and the second safety valve 321 are opened, when Pt is greater than or equal to P3, the explosion critical pressure values of the first rupture disk 331 and the second rupture disk 341 are triggered, the first rupture disk 331 and the second rupture disk 341, the first safety valve 311 and the second safety valve 321, and the first pressure regulating valve 211 and the second pressure regulating valve 221 are opened simultaneously to perform air discharge and pressure relief, so as to adapt to more complicated and severe transportation conditions, ensure the safety of the storage tank 1, and further meet the actual safe transportation requirements under different transportation conditions.

After the tank wagon reaches the hydrogenation station, the third stop valve 201 is closed, and at this time, the first pressure regulating valve 211 and the second pressure regulating valve 221 of the first pressure relief unit 2 are closed, the first pressure relief unit 2 stops working, and the second pressure relief unit 3 is in a normal working state; the pressure in the storage tank 1 begins to be increased to the transfer pressure, and after partial liquid hydrogen transfer is completed, the storage tank 1 keeps the working pressure unchanged during transfer, and transportation is started without reducing the pressure; if the pressure in the storage tank 1 is abnormally increased during transportation to trigger the take-off pressure of the first safety valve 311 and the second safety valve 321, the first safety valve 311 and the second safety valve 321 are opened, and the hydrogen in the storage tank 1 is subjected to pressure relief through the first safety valve 311, the second safety valve 321 and the second flame arrester 302; if the pressure continues to rise abnormally, the explosion critical pressure values of the first rupture disk 331 and the second rupture disk 341 are triggered, the first rupture disk 331 and the second rupture disk 341 are exploded, and the hydrogen in the storage tank 1 is simultaneously decompressed through the first safety valve 311, the second safety valve 321 and the first rupture disk 331 and the second rupture disk 341, so that the safety of the storage tank 1 is ensured, and the actual safe transportation requirements under different transportation working conditions are further met.

Specifically, a first three-way valve 301 is disposed on the second pressure relief main path 30, an inlet of the first three-way valve 301 is connected with the second pressure relief main path 30, a first outlet of the first three-way valve 301 connects the first high-pressure relief branch 31 and the third high-pressure relief branch 33 in parallel, and a second outlet of the first three-way valve 301 connects the second high-pressure relief branch 32 and the fourth high-pressure relief branch 34 in parallel.

It should be noted that, referring to fig. 1-3, the first outlet of the first three-way valve 301 connects the first high-pressure relief branch 31 and the third high-pressure relief branch 33 in parallel at the same time, so that the first safety valve 311 and the first rupture disk 331 form a first high-pressure relief branch unit; the second outlet of the first three-way valve 301 connects the second high-pressure relief branch 32 and the fourth high-pressure relief branch 34 in parallel, so that the second safety valve 321 and the second rupture disk 341 form a second high-pressure relief branch unit, the first three-way valve 301 is in a middle position state in the normal working process, so that the first safety valve 311 and the second safety valve 321 can both be communicated with the second relief main path 30, and the first rupture disk 331 and the second rupture disk 341 can both be communicated with the second relief main path 30, thereby enhancing the reliability of the system; during maintenance and replacement, one of the safety valves is ensured to be in a normal working state during maintenance and replacement by switching the first three-way valve 301. In summary, by switching the first three-way valve 301, at least one of the first high-pressure relief branch unit and the second high-pressure relief branch unit is in a working state, which not only improves the reliability of the system, but also facilitates maintenance and replacement.

Specifically, the storage tank 1 is also connected with a second hydrogen pipeline 12; the hydrogen pressure relief system further comprises a third pressure relief unit 4, and the third pressure relief unit 4 comprises:

a safety hydrogen discharger 41;

a temperature return device 42, wherein a first port of the temperature return device 42 is connected with the first hydrogen pipeline 11 through a third pressure relief main path 40, and a second port of the temperature return device 42 is simultaneously connected with the safety hydrogen discharger 41 and the second hydrogen pipeline 12;

a fourth stop valve 401, disposed on the third pressure relief main path 40, is adapted to selectively communicate the first hydrogen pipeline 11 with the thermostat 42.

It should be noted that, the third pressure relief unit 4 is a manual pressure relief unit; the liquid hydrogen is a dangerous article which is deep low-temperature, inflammable and explosive, the manual discharge system before improvement adopts a direct empty discharge mode, on one hand, the temperature of the hydrogen in the storage tank 1 is low, the low-temperature hydrogen is easy to contact with moisture in the air to be condensed into ice during discharge, so that a discharge port is blocked, on the other hand, the hydrogen is intensively discharged, the hydrogen concentration is easy to be overhigh in a short time, and potential safety hazards are brought; according to the invention, the temperature recoverer 42 is arranged, so that the first port of the temperature recoverer 42 is connected with the first hydrogen pipeline 11 through the third pressure relief main path 40, and the second port of the temperature recoverer 42 is simultaneously connected with the safety hydrogen discharger 41 and the second hydrogen pipeline 12, so that low-temperature hydrogen in the storage tank 1 can be subjected to heat exchange with the atmosphere to be heated to normal-temperature hydrogen after passing through the temperature recoverer 42, thereby not only avoiding the condensation into ice when low-temperature hydrogen is discharged, preventing the discharge port from being blocked, but also reducing the hydrogen concentration by heating and avoiding potential safety hazards caused by overhigh hydrogen concentration.

Specifically, the third pressure relief unit 4 further includes:

a second three-way valve 43, wherein an inlet of the second three-way valve 43 is connected with a second port of the thermostat 42, a first outlet of the second three-way valve 43 is connected with the safety hydrogen discharger 41, and a second outlet of the second three-way valve 43, an exhaust end of the first low-pressure relief branch 21 and an exhaust end of the second low-pressure relief branch 22 are simultaneously connected with the first flame arrester 202;

a check valve 44 disposed between the second three-way valve 43 and the thermostat 42;

a fifth shut-off valve 45, disposed between the thermostat 42 and the check valve 44, is adapted to selectively communicate the thermostat 42 with the safety hydrogen discharger 41.

It should be noted that, referring to fig. 1 and fig. 4, if the liquid hydrogen tank truck is required to manually discharge hydrogen during transportation, the fourth stop valve 401 may be opened, after the low-temperature hydrogen in the storage tank 1 passes through the temperature recoverer 42, the low-temperature hydrogen exchanges heat with the atmosphere, absorbs the heat of the atmosphere and heats up to normal-temperature hydrogen, and then passes through the fifth stop valve 45, the one-way valve 44 and the second three-way valve 43 in sequence to enter the safety hydrogen discharger 41; the low-temperature hydrogen is returned to normal-temperature hydrogen and then discharged through the temperature return device 42, so that potential safety hazards caused by direct discharge of the low-temperature hydrogen are avoided.

Referring to fig. 1 and 4, in this embodiment, the safety hydrogen discharger 41 includes two sets of branch discharge pipes (not shown in the drawings), each branch discharge pipe is uniformly provided with a plurality of discharge end branches (not shown in the drawings), the discharge ports of the discharge end branches are downward, and hydrogen is discharged into the air from a plurality of discharge end branches arranged on the two sets of branch discharge pipes, so that the short-time concentration of hydrogen in the air during hydrogen discharge is reduced, the temperature rise through the temperature return device 42 and the multi-point discharge of a plurality of discharge end branches are performed, the potential safety hazard of condensation into ice and short-time concentration excessively caused during direct hydrogen discharge is avoided, and the hydrogen discharge safety is ensured.

Example two

Referring to fig. 1, fig. 5 and fig. 6, the present embodiment provides a nitrogen purge replacement system of the hydrogen pressure relief system.

Specifically, a sixth stop valve 51 is further disposed on the first low pressure relief branch 21 and/or the second low pressure relief branch 22, and the sixth stop valve 51 is in a normally closed state;

the first high-pressure relief branch 31, the second high-pressure relief branch 32, the third high-pressure relief branch 33 and/or the fourth high-pressure relief branch 34 are further provided with a seventh stop valve 52, and the seventh stop valve 52 is in a normally closed state.

It should be noted that, referring to fig. 1 and fig. 5, a sixth stop valve 51 is further disposed on the first low pressure relief branch 21 and the second low pressure relief branch 22, and the sixth stop valve 51 is in a normally closed state under the transportation condition; referring to fig. 1 and 6, a seventh stop valve 52 is further disposed on the first high-pressure relief branch 31, the second high-pressure relief branch 32, the third high-pressure relief branch 33 and/or the fourth high-pressure relief branch 34, and the seventh stop valve 52 is in a normally closed state. When the hydrogen is injected for the first time, nitrogen purging is carried out in the pipeline through the sixth stop valve 51 and/or the seventh stop valve 52, so that the safety of hydrogen injection is ensured; before the valve is replaced, nitrogen purging is performed into the pipeline through the sixth stop valve 51 and/or the seventh stop valve 52, so that hydrogen in the pipeline is blown out, and operation safety is ensured.

Example III

This embodiment provides a liquid hydrogen transportation tank car, includes: tank car body, and hydrogen pressure release system as described above.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A hydrogen pressure relief system, comprising:

a storage tank (1) on which a first hydrogen pipe (11) is connected;

the first pressure relief unit (2), the first pressure relief unit (2) is connected with the first hydrogen pipeline (11) through a first pressure relief main path (20); the first pressure relief unit (2) comprises a first low-pressure relief branch (21) and a second low-pressure relief branch (22) which are arranged in parallel; the air inlet end of the first low-pressure relief branch (21) and the air inlet end of the second low-pressure relief branch (22) are connected with the first pressure relief main path (20), and the air outlet end of the first low-pressure relief branch (21) and the air outlet end of the second low-pressure relief branch (22) are connected with a first flame arrester (202);

a first pressure regulating valve (211) arranged on the first low pressure relief branch (21);

a second pressure regulating valve (221) arranged on the second low-pressure relief branch (22);

the release pressure of the first pressure regulating valve (211) and/or the second pressure regulating valve (221) is P1, the real-time pressure in the storage tank (1) is Pt, and when Pt is more than or equal to P1, the first pressure regulating valve (211) and/or the second pressure regulating valve (221) is/are opened to release pressure in the storage tank (1).

2. The hydrogen pressure relief system according to claim 1, characterized in that a first shut-off valve (212) is further arranged on the first low pressure relief branch (21), one end of the first shut-off valve (212) is connected with the first pressure regulating valve (211), and the other end is adapted to be connected with the first pressure relief main circuit (20);

the second low-pressure relief branch (22) is further provided with a second stop valve (222), one end of the second stop valve (222) is connected with the second pressure regulating valve (221), and the other end of the second stop valve is suitable for being connected with the first pressure relief main path (20).

3. The hydrogen pressure relief system according to claim 2, characterized in that a third shut-off valve (201) is arranged on the first pressure relief main circuit (20), an inlet of the third shut-off valve (201) is connected with the first pressure relief main circuit (20), and an outlet of the third shut-off valve (201) connects the first low pressure relief branch circuit (21) and the second low pressure relief branch circuit (22) in parallel at the same time.

4. The hydrogen pressure relief system according to claim 1, further comprising a second pressure relief unit (3), wherein the second pressure relief unit (3) is connected to the first hydrogen pipe (11) by a second pressure relief main (30);

the second pressure relief unit (3) comprises a first high-pressure relief branch (31) and a second high-pressure relief branch (32) which are arranged in parallel, the air inlet end of the first high-pressure relief branch (31) and the air inlet end of the second high-pressure relief branch (32) are connected with the second pressure relief main path (30), and the air outlet end of the first high-pressure relief branch (31) and the air outlet end of the second high-pressure relief branch (32) are connected with the second flame arrester (302);

a first safety valve (311) is arranged on the first high-pressure relief branch (31), a second safety valve (321) is arranged on the second high-pressure relief branch (32), and the tripping pressure of the first safety valve (311) and/or the second safety valve (321) is P2, wherein P2 is more than P1; when Pt is more than or equal to P2, the first safety valve (311) and/or the second safety valve (321) are/is opened to release pressure in the storage tank (1).

5. The hydrogen pressure relief system according to claim 4, characterized in that the second pressure relief unit (3) further comprises a third high pressure relief branch (33) and a fourth high pressure relief branch (34) arranged in parallel, the air inlet end of the third high pressure relief branch (33) and the air inlet end of the fourth high pressure relief branch (34) are both connected with the second pressure relief main circuit (30), and the air outlet end of the third high pressure relief branch (33) and the air outlet end of the fourth high pressure relief branch (34) are both connected with a third flame arrester (303);

the third high-pressure relief branch (33) is provided with a first rupture disk (331), the fourth high-pressure relief branch (34) is provided with a second rupture disk (341), and the explosion critical pressure of the first rupture disk (331) and/or the second rupture disk (341) is P3, wherein P3 is more than P2; when Pt is more than or equal to P3, the first rupture disk (331) and/or the second rupture disk (341) are/is blasted to release pressure inside the storage tank (1).

6. The hydrogen pressure relief system according to claim 5, characterized in that a first three-way valve (301) is arranged on the second pressure relief main path (30), an inlet of the first three-way valve (301) is connected with the second pressure relief main path (30), a first outlet of the first three-way valve (301) connects the first high pressure relief branch path (31) and the third high pressure relief branch path (33) in parallel at the same time, and a second outlet of the first three-way valve (301) connects the second high pressure relief branch path (32) and the fourth high pressure relief branch path (34) in parallel at the same time.

7. The hydrogen pressure relief system according to any of claims 1-6, characterized in that a second hydrogen pipe (12) is also connected to the tank (1); the hydrogen pressure relief system further comprises a third pressure relief unit (4), and the third pressure relief unit (4) comprises:

a safety hydrogen discharger (41);

the first port of the temperature return device (42) is connected with the first hydrogen pipeline (11) through a third pressure relief main circuit (40), and the second port of the temperature return device (42) is simultaneously connected with the safety hydrogen discharger (41) and the second hydrogen pipeline (12);

and a fourth stop valve (401) is arranged on the third pressure relief main path (40) and is suitable for selectively communicating the first hydrogen pipeline (11) with the temperature return device (42).

8. The hydrogen pressure relief system according to claim 7, wherein the third pressure relief unit (4) further comprises:

the inlet of the second three-way valve (43) is connected with the second port of the temperature return device (42), the first outlet of the second three-way valve (43) is connected with the safety hydrogen discharge device (41), and the second outlet of the second three-way valve (43), the exhaust end of the first low-pressure release branch (21) and the exhaust end of the second low-pressure release branch (22) are simultaneously connected with the first flame arrester (202);

a check valve (44) provided between the second three-way valve (43) and the thermostat (42);

and a fifth stop valve (45) provided between the thermostat (42) and the check valve (44) and adapted to selectively communicate the thermostat (42) with the safety hydrogen discharger (41).

9. The hydrogen pressure relief system according to claim 5, characterized in that a sixth shut-off valve (51) is further arranged on the first low pressure relief branch (21) and/or the second low pressure relief branch (22), the sixth shut-off valve (51) being in a normally closed state;

the first high-pressure relief branch circuit (31), the second high-pressure relief branch circuit (32), the third high-pressure relief branch circuit (33) and/or the fourth high-pressure relief branch circuit (34) are/is further provided with a seventh stop valve (52), and the seventh stop valve (52) is in a normally closed state.

10. A liquid hydrogen transportation tank car, comprising:

tank truck body, and hydrogen pressure relief system according to any of the preceding claims 1-9.