A storage tank cold box system for liquid hydrogen pump feed

Abstract

The application provides a liquid hydrogen pump liquid supply storage tank cold box system, and particularly relates to the low-temperature test technical field.The liquid hydrogen pump liquid supply storage tank cold box system integrates a liquid hydrogen storage tank, a pipeline, and valves, sensors and other devices in an internal test unit in a cold box, can solve the problem that heat leakage of multiple device nodes may cause liquid hydrogen vaporization, maximally reduces liquid hydrogen evaporation, saves liquid hydrogen consumption, and has high safety.

Description

Technical Field

[0001] This invention relates to the field of cryogenic testing technology, and in particular to a storage tank cold box system for liquid hydrogen pump supply. Background Technology

[0002] In the hydrogen energy industry chain, liquid hydrogen can be used as a fuel energy source in the automotive industry. Its energy can provide power for automobiles. As a form of hydrogen, liquid hydrogen has a larger storage capacity than gaseous hydrogen, which is beneficial to increasing the driving range of automobiles. At the same time, liquid hydrogen refueling stations have the advantages of smaller footprint and larger capacity compared to high-pressure hydrogen refueling stations.

[0003] Liquid hydrogen pumps and liquid hydrogen containers are the core equipment of liquid hydrogen refueling stations. As an important component for liquid hydrogen transportation applications, liquid hydrogen pumps are mainly divided into high-pressure liquid hydrogen pumps and liquid hydrogen pools, and high-flow-rate liquid hydrogen centrifugal pumps. The pressure of the liquid hydrogen high-pressure pump liquid hydrogen pool can reach up to 100MPa, which can be used to fill high-pressure hydrogen. The liquid hydrogen centrifugal pump is used to fill liquid hydrogen, with a maximum flow rate of up to 12L / s. Existing liquid hydrogen pumps are mainly non-submersible. With the development of technology, submersible liquid hydrogen pumps have the characteristics of low static evaporation rate, which has obvious advantages over non-submersible pumps in terms of vaporization suppression and rapid start-up. The submersible structure can provide better inlet subcooling for liquid hydrogen pumps, and after long-term static storage, there is no need to re-precool the liquid hydrogen pump system.

[0004] In the existing technology, most liquid hydrogen pump performance testing platforms are open systems, which makes it difficult to eliminate the impact of tank heat leakage on pump characteristics, leading to problems such as heat leakage and liquid hydrogen vaporization.

[0005] In view of this, the present invention provides a storage tank cold box system that can reduce heat leakage. Summary of the Invention

[0006] To address the issues of heat leakage and liquid hydrogen vaporization in existing testing platforms, this invention proposes a storage tank cold box system for liquid hydrogen pump supply.

[0007] This invention is achieved through the following technical solution:

[0008] This invention proposes a cold box system for a liquid hydrogen pump supply tank, comprising a cold box unit, an internal testing unit, and an external testing unit, wherein:

[0009] The cold box unit includes a cold box, and a liquid hydrogen storage tank is installed inside the cold box;

[0010] The external testing unit includes a submersible pump liquid hydrogen tank, a flow meter, a high-pressure pump liquid hydrogen tank, and a second vaporizer. The submersible pump liquid hydrogen tank and the high-pressure pump liquid hydrogen tank are respectively equipped with a submersible pump and a high-pressure pump.

[0011] The liquid hydrogen inlet is connected to the bottom first inlet end and the top first inlet end of the liquid hydrogen storage tank. The bottom third outlet end of the liquid hydrogen storage tank is connected to the liquid hydrogen pool inlet end of the submersible pump, the inlet end of the second vaporizer, and the inlet end of the liquid hydrogen pool of the high-pressure pump, respectively. The outlet end of the liquid hydrogen pool of the high-pressure pump is connected to the high-pressure vaporizer.

[0012] The second inlet end of the top of the liquid hydrogen storage tank is connected to the return gas port of the high-pressure pump liquid hydrogen pool and the return gas port of the submersible pump liquid hydrogen pool, respectively.

[0013] The internal testing unit includes a high-pressure pump testing section and a submersible pump testing section. The submersible pump testing section includes: a third regulating valve and a second temperature and pressure sensor sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the submersible pump; and a flow meter, a first temperature and pressure sensor, a second regulating valve, and a second check valve sequentially arranged from the liquid hydrogen pool outlet end of the submersible pump to the bottom second inlet end of the liquid hydrogen storage tank. The high-pressure pump testing section includes: a fourth regulating valve, a third temperature and pressure sensor, and a liquid hydrogen filter sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the high-pressure pump; and a high-pressure vaporizer connected from the liquid hydrogen pool outlet end of the high-pressure pump. Both the high-pressure pump testing section and the submersible pump testing section are located inside the cold box.

[0014] Furthermore, it also includes a pressurization unit, which includes a first vaporizer and a first regulating valve. The bottom second outlet of the liquid hydrogen storage tank is sequentially connected to the first regulating valve, the first vaporizer, and the top third inlet of the liquid hydrogen storage tank.

[0015] Furthermore, it also includes a venting unit, which includes a flame arrester, a third check valve, a venting tower, and a drain valve. The outlet end of the second vaporizer is connected to the flame arrester and the third check valve in sequence, and the outlet end of the third check valve is connected to the venting tower and the drain valve respectively.

[0016] Furthermore, it also includes a monitoring unit, which includes a first pressure gauge, a gas phase hand valve, a balance valve, a level gauge, and a liquid phase hand valve. The bottom first outlet end of the liquid hydrogen storage tank is connected to the liquid phase hand valve, and the outlet end of the liquid phase hand valve is connected to one end of the level gauge and one end of the balance valve, respectively. The top first outlet end of the liquid hydrogen storage tank is connected to the gas phase hand valve, and the outlet end of the gas phase hand valve is connected to the other end of the level gauge and the other end of the balance valve, respectively.

[0017] Furthermore, the liquid hydrogen inlet is sequentially connected to the first check valve and the cryogenic filter inside the cold box, and from the outlet end of the cryogenic filter, it is connected to the bottom first inlet end of the liquid hydrogen storage tank via the second shut-off valve and the top first inlet end of the liquid hydrogen storage tank via the first shut-off valve. A branch of the outlet end of the cryogenic filter is connected to the first manual vent valve and the first safety valve outside the cold box.

[0018] Furthermore, it also includes a safety venting unit, which includes a backup hand valve, a first pneumatic venting valve, and a second pneumatic venting valve. The first branch of the second outlet end at the top of the liquid hydrogen storage tank is connected to the backup hand valve, the first pneumatic venting valve, and the inlet of the second vaporizer, respectively. The second branch of the second outlet end at the top of the liquid hydrogen storage tank is connected to the second pneumatic venting valve and the inlet of the second vaporizer, respectively.

[0019] Furthermore, the safety venting unit also includes a first rupture disc, a first safety valve, a three-way valve, a second rupture disc, and a second safety valve. The third branch of the second outlet at the top of the liquid hydrogen storage tank is connected to the three-way valve. One end of the three-way valve is connected in series with the first safety valve and the first rupture disc, and the other end is connected in series with the second safety valve and the second rupture disc. Both the first safety valve and the second safety valve are connected to the second vaporizer and then reheated before entering the venting tower for discharge.

[0020] Furthermore, the return gas port of the high-pressure pump liquid hydrogen pool and the return gas port of the submersible pump liquid hydrogen pool are connected to the inlet end of the second vaporizer. An exhaust valve, a fourth safety valve, and a fifth safety valve are respectively provided between the return gas port of the submersible pump liquid hydrogen pool, the return gas port of the high-pressure pump liquid hydrogen pool, the liquid outlet of the submersible pump liquid hydrogen pool, and the inlet end of the second vaporizer.

[0021] Furthermore, a first return gas shut-off valve and a second return gas shut-off valve are respectively installed between the return gas port of the submersible pump liquid hydrogen pool and the return gas port of the high-pressure pump liquid hydrogen pool and the second inlet end of the top of the liquid hydrogen storage tank. A fourth regulating valve is also installed between the inlet end of the second vaporizer and the third outlet end of the bottom of the liquid hydrogen storage tank. The first return gas shut-off valve, the second return gas shut-off valve and the fourth regulating valve are located inside the cold box.

[0022] Furthermore, it also includes a purging unit, which includes a purging regulating valve. The purging regulating valve is connected to the bottom first inlet end and the bottom third outlet end of the liquid hydrogen storage tank, respectively. An explosion-proof safety device is connected to the outer shell of the cold box. A vacuum valve and a vacuum measuring valve are connected to the cold box, and the vacuum measuring valve is connected to the vacuum gauge tube.

[0023] The beneficial effects of this invention are:

[0024] (1) The cold box system for liquid hydrogen pump supply proposed in this invention integrates liquid hydrogen storage tank, pipeline, and valves, sensors and other devices in the internal test unit into the cold box. It can solve the problem of liquid hydrogen vaporization caused by heat leakage in multiple device nodes, minimize liquid hydrogen evaporation, save liquid hydrogen consumption and have high safety.

[0025] (2) The storage tank cold box system for liquid hydrogen pump supply proposed in this invention has a pressurization unit and a venting unit to regulate the pressure inside the liquid hydrogen storage tank, which can accurately control the filling flow rate and pressure, so as to facilitate the testing of high pressure pumps and submersible pumps.

[0026] (3) The storage tank cold box system for liquid hydrogen pump supply proposed in this invention can provide a stable source of liquid hydrogen for submersible pump and high pressure pump testing, and can also recycle liquid hydrogen and recover cold energy, making operation more convenient. Attached Figure Description

[0027] Figure 1 This is an overall structural diagram of the storage tank cold box system for liquid hydrogen pump supply according to the present invention;

[0028] In the diagram: Cold box 1, Liquid hydrogen storage tank 2, First pressure gauge 3, Gas phase manual valve 4, Balancing valve 5, Level gauge 6, Liquid phase manual valve 7, First safety valve 8, First manual vent valve 9, First check valve 10, Cryogenic filter 11, First shut-off valve 12, Second shut-off valve 13, First regulating valve 14, First vaporizer 15, First pneumatic vent valve 16, Standby manual valve 17, Second pneumatic vent valve 18, First rupture disc 19, Second safety valve 20, Three-way valve 21, Third safety valve 22, Second rupture disc 23, Fourth safety valve 24, Second check valve 25, Second regulating valve 26, ... Temperature and pressure sensor 27, flow meter 28, exhaust valve 29, first return gas shut-off valve 30, second temperature and pressure sensor 31, third regulating valve 32, second return gas shut-off valve 33, fourth regulating valve 34, fourth regulating valve 35, third temperature and pressure sensor 36, liquid hydrogen filter 37, fifth safety valve 38, submersible pump liquid hydrogen tank 39, high-pressure pump liquid hydrogen tank 40, second vaporizer 41, flame arrester 42, third check valve 43, venting tower 44, drain valve 45, purging regulating valve 46, explosion-proof safety device 47, vacuum gauge 48, vacuum measuring valve 49, vacuum extraction valve 50.

[0029] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0030] To more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0031] Please refer to Figure 1This invention proposes a storage tank cold box 1 system for liquid hydrogen pump supply, comprising a cold box 1 unit, an internal testing unit, and an external testing unit, wherein:

[0032] The cold box unit includes a cold box 1, and a liquid hydrogen storage tank 2 is installed inside the cold box 1;

[0033] The external testing unit includes a submersible pump liquid hydrogen tank 39, a flow meter 28, a high-pressure pump liquid hydrogen tank 40, and a second vaporizer 41. Submersible pumps and high-pressure pumps are respectively installed in the submersible pump liquid hydrogen tank 39 and the high-pressure pump liquid hydrogen tank 40.

[0034] The liquid hydrogen inlet is connected to the bottom first inlet end and the top first inlet end of the liquid hydrogen storage tank 2. The bottom third outlet end of the liquid hydrogen storage tank 2 is connected to the inlet end of the submersible pump liquid hydrogen pool 39, the inlet end of the second vaporizer 41 and the inlet end of the high pressure pump liquid hydrogen pool 40 respectively. The outlet end of the high pressure pump liquid hydrogen pool 40 is connected to the high pressure vaporizer.

[0035] The top second inlet of the liquid hydrogen storage tank 2 is connected to the return gas port of the high-pressure pump liquid hydrogen pool 40 and the return gas port of the submersible pump liquid hydrogen pool 39. A first return gas shut-off valve 30 and a second return gas shut-off valve 33 are respectively installed between the return gas port of the submersible pump liquid hydrogen pool 39 and the return gas port of the high-pressure pump liquid hydrogen pool 40 and the top second inlet of the liquid hydrogen storage tank 2. A fourth regulating valve 34 is also installed between the inlet of the second vaporizer 41 and the bottom third outlet of the liquid hydrogen storage tank 2. The first return gas shut-off valve 30, the second return gas shut-off valve 33 and the fourth regulating valve 34 are located inside the cold box 1.

[0036] The internal testing unit includes a high-pressure pump testing section and a submersible pump testing section. The submersible pump testing section includes: a third regulating valve 32 and a second temperature and pressure sensor 31 sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the submersible pump; and a flow meter 28, a first temperature and pressure sensor 27, a second regulating valve 26, and a second check valve 25 sequentially arranged from the liquid hydrogen pool outlet end of the submersible pump to the bottom second inlet end of the liquid hydrogen storage tank. The high-pressure pump testing section includes: a fourth regulating valve 35, a third temperature and pressure sensor 36, and a liquid hydrogen filter 37 sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the high-pressure pump; and a high-pressure vaporizer located from the liquid hydrogen pool outlet end of the high-pressure pump. Both the high-pressure pump testing section and the submersible pump testing section are located inside the cold box 1.

[0037] In this embodiment:

[0038] Liquid hydrogen storage tank 2 is used to store liquid hydrogen;

[0039] The high-pressure pump liquid hydrogen tank 40 and the submersible pump liquid hydrogen tank 39 are used to test the high-pressure pump and the submersible pump.

[0040] The second vaporizer 41 and the high-pressure vaporizer are used to recover the cold energy of liquid hydrogen and cryogenic hydrogen.

[0041] The second check valve 25 is used to prevent liquid hydrogen from flowing back;

[0042] The third regulating valve 32 is used to control the flow rate of liquid hydrogen entering the submersible pump circulation;

[0043] The first temperature and pressure sensor 27, the second temperature and pressure sensor 31, and the third temperature and pressure sensor 36 are used to detect the real-time temperature and pressure magnitude.

[0044] Flow meter 28 is used to detect the flow rate of the submersible pump. In a specific embodiment, a high-pressure pump and a submersible pump are installed in the high-pressure pump liquid hydrogen pool 40 and the submersible pump liquid hydrogen pool 39. During testing, liquid hydrogen from the liquid hydrogen inlet is added to the liquid hydrogen storage tank 2 through the bottom first inlet and the top first inlet. The liquid hydrogen in the liquid hydrogen storage tank 2 is supplied to the submersible pump and the high-pressure pump through the bottom third outlet. For the submersible pump test, the liquid hydrogen flows out through the bottom third outlet of the liquid hydrogen storage tank, passes through the third regulating valve 32 and the second temperature and pressure sensor 31 in sequence, and enters the submersible pump liquid hydrogen pool 39. When the liquid level in the submersible pump pool reaches about 90%, the third regulating valve 32 is closed. For the high-pressure pump test, the liquid hydrogen flows out through the bottom third outlet of the liquid hydrogen storage tank, passes through the fourth regulating valve 35 and the third temperature and pressure sensor 36 in sequence, and enters the high-pressure pump liquid hydrogen pool 40. When the liquid level in the high-pressure pump pool reaches about 90%, the fourth regulating valve 35 is closed. After filling the two pump tanks, the submersible pump and the high-pressure pump are turned on. The pump speed is changed, and the data of the submersible pump and the high-pressure pump are recorded by the first temperature and pressure sensor 27, the second temperature and pressure sensor 31, the flow meter 28, and the third temperature and pressure sensor 36, etc., to complete the test of the submersible pump and the high-pressure pump. In this application, the liquid hydrogen storage tank 2, pipelines, and valves, sensors and other devices in the internal test unit are integrated into the cold box 1, which can solve the problem of liquid hydrogen vaporization caused by heat leakage in multiple device nodes, minimize liquid hydrogen evaporation, save liquid hydrogen consumption and have high safety.

[0045] In one embodiment, the outlet pipe of the submersible pump can be connected back to the liquid phase space of the liquid hydrogen storage tank 2 via a Bayonet cryogenic connector to form a circulation, thereby reducing the consumption of liquid hydrogen. Furthermore, a pressurization unit is also included, comprising a first vaporizer 15 and a first regulating valve 14. The bottom second outlet of the liquid hydrogen storage tank 2 is sequentially connected to the first regulating valve 14, the first vaporizer 15, and the top third inlet of the liquid hydrogen storage tank 2.

[0046] In this embodiment:

[0047] The first vaporizer 15 is used to convert liquid hydrogen into gaseous hydrogen;

[0048] In a specific embodiment, the first vaporizer 15 and the first regulating valve 14 are located outside the cold box 1. The first vaporizer 15 can exchange heat with air via convection or with other gases or liquids. Liquid hydrogen enters the second vaporizer 15 through the first regulating valve 14, and is then converted into hydrogen gas in the second vaporizer 15 and enters the top of the liquid hydrogen storage tank 2 to self-pressurize the liquid hydrogen storage tank 2.

[0049] Furthermore, it also includes a venting unit, which includes a flame arrester 42, a third check valve 43, a venting tower 44, and a drain valve 45. The outlet end of the second vaporizer 41 is connected to the flame arrester 42 and the third check valve 43 in sequence, and the outlet end of the third check valve 43 is connected to the venting tower 44 and the drain valve 45 respectively.

[0050] In this embodiment:

[0051] Venting tower 44 is used to vent hydrogen gas after testing;

[0052] In a specific embodiment, liquid hydrogen or cryogenic hydrogen is converted into near-room temperature gaseous hydrogen after passing through the second vaporizer 41, and finally passes through the flame arrester 42 and the check valve in sequence before entering the venting tower 44 for venting.

[0053] Furthermore, it also includes a monitoring unit, which includes a first pressure gauge 3, a weather valve 4, a balancing valve 5, a level gauge 6, and a liquid phase valve 7. The bottom first outlet end of the liquid hydrogen storage tank 2 is connected to the liquid phase valve 7, and one end of the level gauge 6 and one end of the balancing valve 5 are respectively connected from the outlet end of the liquid phase valve 7. The top first outlet end of the liquid hydrogen storage tank 2 is connected to the weather valve 4, and the other end of the level gauge 6 and the other end of the balancing valve 5 are respectively connected from the outlet end of the weather valve 4.

[0054] In this embodiment:

[0055] The level gauge 6 is used to detect the liquid hydrogen level in the liquid hydrogen storage tank 2;

[0056] The pressure gauge is used to detect the pressure inside liquid hydrogen storage tank 2;

[0057] In a specific implementation, when the pressure and liquid level in the liquid hydrogen storage tank 2 are detected, the weather hand valve 4 and the liquid phase hand valve 7 are opened, and then the pressure gauge 3 and the liquid level gauge 6 will display the pressure of liquid hydrogen and the liquid level of liquid hydrogen in the liquid hydrogen storage tank 2 respectively.

[0058] Furthermore, the liquid hydrogen inlet is sequentially connected to the first check valve 10 and the cryogenic filter 11 inside the cold box 1, and from the outlet end of the cryogenic filter 11, it is connected to the bottom first inlet end of the liquid hydrogen storage tank 2 via the second shut-off valve 13 and the top first inlet end of the liquid hydrogen storage tank 2 via the first shut-off valve 12. A branch of the outlet end of the cryogenic filter 11 is connected to the first manual vent valve 9 and the first safety valve 8 outside the cold box 1.

[0059] In this embodiment:

[0060] The first vent valve 9 is used to manually release a portion of the liquid hydrogen in case of overpressure.

[0061] The first safety valve 8 is used to actively discharge liquid hydrogen in case of overpressure.

[0062] Cryogenic filter 11 is used to filter impurities in liquid hydrogen;

[0063] The first shut-off valve 13 and the second shut-off valve 12 are used to control the addition of liquid hydrogen;

[0064] The second check valve 10 is used to prevent liquid hydrogen from flowing back;

[0065] In a specific implementation, if the liquid hydrogen storage tank 2 is being filled for the first time, the first shut-off valve 12 is closed and the second shut-off valve 13 is opened. Liquid hydrogen is slowly added to the liquid hydrogen storage tank 2 and pre-cooled. Then, the second shut-off valve 13 is closed and the first shut-off valve 12 is opened for top filling until the filling is complete. If it is not the first filling and some liquid hydrogen remains in the liquid hydrogen storage tank, the first shut-off valve 12 and the second shut-off valve 13 can be opened simultaneously according to the liquid level in the liquid hydrogen storage tank, allowing liquid to enter from the top and bottom at the same time, thus accelerating the liquid hydrogen filling speed. At this time, since the temperature of the liquid hydrogen entering from the top is lower than the temperature of the gas phase space inside the storage tank, the gas in the gas phase space is liquefied, the pressure in the storage tank drops, and the liquid hydrogen delivery speed is maintained. After the liquid hydrogen storage tank 2 is filled, the first shut-off valve 12 and the second shut-off valve 13 are closed. The remaining liquid hydrogen in the pipeline between the first check valve 10 and the first shut-off valve 12 and the second shut-off valve 13 can be discharged through the first manual vent valve 9 and the first safety valve 8.

[0066] Furthermore, it also includes a safety venting unit, which includes a backup hand valve 17, a first pneumatic venting valve 16, and a second pneumatic venting valve 18. The first branch of the second outlet end at the top of the liquid hydrogen storage tank is connected to the backup hand valve 17, the first pneumatic venting valve 16, and the inlet of the second vaporizer 41, respectively. The second branch of the second outlet end at the top of the liquid hydrogen storage tank is connected to the second pneumatic venting valve 18 and the inlet of the second vaporizer 41, respectively.

[0067] In this embodiment:

[0068] The first pneumatic vent valve 16 is a pneumatic control valve used to precisely control exhaust pressure and flow.

[0069] The spare hand valve 17 is a manually operated switch valve, used in case of emergency when the first pneumatic vent valve fails.

[0070] The second pneumatic vent valve is a pneumatic on / off valve used to automatically release pressure when there is overpressure.

[0071] In a specific implementation, when the pressure is too high, the first pneumatic vent valve 16 or the second pneumatic vent valve 18 will automatically open. When the pressure in the liquid hydrogen storage tank 2 is too high, the standby hand valve 17 and the first pneumatic switch valve 16 can be opened to release hydrogen. Alternatively, the pneumatic vent valve 18 can be opened further to perform emergency pressure relief and stabilize the pressure in the liquid hydrogen storage tank 2.

[0072] Furthermore, the safety venting unit also includes a first rupture disc 19, a first safety valve 20, a three-way valve 21, a second rupture disc 22, and a second safety valve 23. The third branch of the second outlet at the top of the liquid hydrogen storage tank is connected to the three-way valve 21. One end of the three-way valve 21 is connected in series with the first safety valve 20 and the first rupture disc 19, and the other end is connected in series with the second safety valve 23 and the second rupture disc 22. Both the first safety valve 20 and the second safety valve 23 are connected to the second vaporizer and then reheated before entering the venting tower 44 for discharge.

[0073] In this embodiment:

[0074] Three-way valve 21 is used to connect multiple safety valve branches;

[0075] The first safety valve 20 and the first rupture disc 19, the second safety valve 23 and the second rupture disc 22 are all connected in series for automatic pressure relief; in actual operation, one is in use and one is on standby to prevent safety valve failure.

[0076] In a specific implementation, both the safety valve and the rupture disc are pre-set with pressure values. When the pressure inside the liquid hydrogen storage tank 2 exceeds the set value, they automatically open. One end of the three-way valve 21 is connected to the second outlet end at the top of the liquid hydrogen storage tank 2, and the other two ends are connected to two branches respectively. Safety valves and rupture discs are installed on both branches. When the pressure inside the liquid hydrogen storage tank 2 is too high, the first pneumatic vent valve 16 or the second pneumatic vent valve 18 can be opened to release the pressure, or the first safety valve 20 or the second safety valve 22 can be automatically opened to complete the pressure release.

[0077] Furthermore, the return gas port of the high-pressure pump liquid hydrogen pool 40 and the return gas port of the submersible pump liquid hydrogen pool 39 are connected to the inlet end of the second vaporizer 41. An exhaust valve 29, a fourth safety valve 24 and a fifth safety valve 38 are respectively provided between the return gas port of the submersible pump liquid hydrogen pool 39, the liquid outlet end of the submersible pump liquid hydrogen pool 39, the return gas port of the high-pressure pump liquid hydrogen pool 40 and the inlet end of the second vaporizer 41.

[0078] In this embodiment:

[0079] The third safety valve 38 and the fourth safety valve 24 are used for automatic pressure relief;

[0080] The exhaust valve 29 is used to regulate the overpressure discharge of hydrogen in the return gas pipeline of the submersible pump;

[0081] In a specific implementation, the exhaust valve 29 of the submersible pump return gas pipeline, the safety valve 24 of the submersible pump outlet pipeline, and the safety valve 38 of the high-pressure pump pipeline are all pre-set with pipeline pressure values. When the pressure in the pipeline exceeds the set value, they will automatically open to discharge liquid hydrogen or cryogenic hydrogen to the second vaporizer 41 for recovery of cold energy.

[0082] In one embodiment, when the pressure inside the liquid hydrogen storage tank 2 is too high or when it is necessary to release liquid hydrogen urgently, the fourth regulating valve 34 automatically opens, and the liquid hydrogen in the liquid hydrogen storage tank 2 is converted into hydrogen gas through the second vaporizer 41, and the cold energy is recovered and discharged into the venting tower 44.

[0083] Furthermore, a first return gas shut-off valve 30 and a second return gas shut-off valve 33 are respectively installed between the return gas port of the liquid hydrogen pool 39 of the submersible pump and the return gas port of the liquid hydrogen pool 40 of the high-pressure pump and the second inlet end of the top of the liquid hydrogen storage tank 2. A fourth regulating valve 34 is also installed between the inlet end of the second vaporizer 41 and the third outlet end of the bottom of the liquid hydrogen storage tank 2. The first return gas shut-off valve 30, the second return gas shut-off valve 33 and the fourth regulating valve 34 are located inside the cold box 1.

[0084] In this embodiment:

[0085] The first return gas shut-off valve 30 and the second return gas shut-off valve 33 are used to regulate the pressure in the liquid hydrogen pool 39 of the submersible pump and the liquid hydrogen pool 40 of the high-pressure pump.

[0086] In one specific embodiment, during the transportation of liquid hydrogen, heat leakage may occur, and some liquid hydrogen will be converted into hydrogen gas. At this time, opening the first return gas shut-off valve 30 and the second return gas shut-off valve 33 will allow hydrogen gas to enter the liquid hydrogen storage tank 2. When the pressure in the liquid hydrogen storage tank 2 is too high, the fourth regulating valve 34 can be opened directly to discharge hydrogen gas into the second vaporizer 41.

[0087] Furthermore, it also includes a purging unit, which includes a purging regulating valve 46. The purging regulating valve 46 is connected to the bottom first inlet end and the bottom third outlet end of the liquid hydrogen storage tank 2, respectively. An explosion-proof safety device 47 is connected to the outer shell of the cold box 1. A vacuum valve 50 and a vacuum measuring valve 49 are respectively connected to the cold box 1. The vacuum measuring valve 49 is connected to a vacuum gauge tube 48.

[0088] In this embodiment:

[0089] Vacuum valve 50 is used for vacuuming cold box 1;

[0090] The purging regulating valve 46 is used to adjust the flow rate of purging nitrogen.

[0091] Vacuum gauge tube 48 and vacuum valve 49 are used to detect the vacuum level of cold box 1;

[0092] In a specific implementation, to ensure the purity of the gas in the pipeline, a purging unit is installed on the cold box 1, and high-purity dry nitrogen is used to purge the pipeline, ensuring that oxygen, water, and other impurities are completely removed and the pipeline is clean. Vacuum gauge 48 and vacuum valve 49 monitor the vacuum level of the cold box 1 to prevent vacuum deterioration. Mechanical pumps and molecular pumps evacuate the cold box 1 through vacuum valve 50, ensuring that the vacuum level of the cold box 1 is better than 1×10⁻⁶ at room temperature. -2 Pa, better than 1×10 at low temperatures -5 Pa.

[0093] Of course, the present invention may have many other embodiments. Based on this embodiment, other embodiments obtained by those skilled in the art without any creative effort are all within the scope of protection of the present invention.

Claims

1. A storage tank cold box system for liquid hydrogen pump supply, characterized in that, It includes a cold box unit, an internal testing unit, a pressurization unit, and an external testing unit, among which: The cold box unit includes a cold box, and a liquid hydrogen storage tank is installed inside the cold box; The external testing unit includes a submersible pump liquid hydrogen tank, a flow meter, a high-pressure pump liquid hydrogen tank, and a second vaporizer. The submersible pump liquid hydrogen tank and the high-pressure pump liquid hydrogen tank are respectively equipped with a submersible pump and a high-pressure pump. The liquid hydrogen inlet is connected to the bottom first inlet end and the top first inlet end of the liquid hydrogen storage tank. The bottom third outlet end of the liquid hydrogen storage tank is connected to the liquid hydrogen pool inlet end of the submersible pump, the liquid hydrogen pool inlet end of the high-pressure pump, and the inlet end of the second vaporizer, respectively. The liquid hydrogen pool outlet end of the high-pressure pump is connected to the high-pressure vaporizer. The second inlet end of the top of the liquid hydrogen storage tank is connected to the return gas port of the high-pressure pump liquid hydrogen pool and the return gas port of the submersible pump liquid hydrogen pool, respectively. The internal testing unit includes a high-pressure pump testing section and a submersible pump testing section. The submersible pump testing section includes: a third regulating valve and a second temperature and pressure sensor sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the submersible pump; and a flow meter, a first temperature and pressure sensor, a second regulating valve, and a second check valve sequentially arranged from the liquid hydrogen pool outlet end of the submersible pump to the bottom second inlet end of the liquid hydrogen storage tank. The high-pressure pump testing section includes a fourth regulating valve, a third temperature and pressure sensor, and a liquid hydrogen filter sequentially arranged from the bottom third outlet end of the liquid hydrogen storage tank to the liquid hydrogen pool inlet end of the high-pressure pump; and a high-pressure vaporizer connected from the liquid hydrogen pool outlet end of the high-pressure pump. Both the high-pressure pump testing section and the submersible pump testing section are located inside the cold box. The pressurization unit includes a first vaporizer and a first regulating valve. The bottom second outlet of the liquid hydrogen storage tank is sequentially connected to the first regulating valve, the first vaporizer, and the top third inlet of the liquid hydrogen storage tank. It also includes a monitoring unit, which includes a first pressure gauge, a gas phase hand valve, a balance valve, a level gauge, and a liquid phase hand valve. The bottom first outlet end of the liquid hydrogen storage tank is connected to the liquid phase hand valve, and the outlet end of the liquid phase hand valve is connected to one end of the level gauge and one end of the balance valve, respectively. The top first outlet end of the liquid hydrogen storage tank is connected to the gas phase hand valve, and the outlet end of the gas phase hand valve is connected to the other end of the level gauge and the other end of the balance valve, respectively. The return gas port of the high-pressure pump liquid hydrogen pool and the return gas port of the submersible pump liquid hydrogen pool are connected to the inlet end of the second vaporizer. An exhaust valve, a fourth safety valve and a fifth safety valve are respectively provided between the return gas port of the submersible pump liquid hydrogen pool, the return gas port of the high-pressure pump liquid hydrogen pool, the liquid outlet of the submersible pump liquid hydrogen pool and the inlet end of the second vaporizer. A first return gas shut-off valve and a second return gas shut-off valve are respectively installed between the return gas port of the liquid hydrogen pool of the submersible pump and the return gas port of the liquid hydrogen pool of the high-pressure pump and the second inlet end of the top of the liquid hydrogen storage tank. A fifth regulating valve is also installed between the inlet end of the second vaporizer and the third outlet end of the bottom of the liquid hydrogen storage tank. The first return gas shut-off valve, the second return gas shut-off valve and the fifth regulating valve are located inside the cold box.

2. The storage tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that, It also includes a venting unit, which includes a flame arrester, a third check valve, a venting tower, and a drain valve. The outlet end of the second vaporizer is connected to the flame arrester and the third check valve in sequence, and the outlet end of the third check valve is connected to the venting tower and the drain valve respectively.

3. The storage tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that, The liquid hydrogen inlet is sequentially connected to the first check valve and the cryogenic filter inside the cold box. From the outlet of the cryogenic filter, it is connected to the bottom first inlet of the liquid hydrogen storage tank via a second shut-off valve and to the top first inlet of the liquid hydrogen storage tank via a first shut-off valve. A branch of the outlet of the cryogenic filter is connected to the first manual vent valve and the first safety valve outside the cold box.

4. The storage tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that, It also includes a safety venting unit, which includes a backup hand valve, a first pneumatic venting valve, and a second pneumatic venting valve. The first branch of the second outlet at the top of the liquid hydrogen storage tank is connected to the backup hand valve, the first pneumatic venting valve, and the inlet of the second vaporizer, respectively. The second branch of the second outlet at the top of the liquid hydrogen storage tank is connected to the second pneumatic venting valve and the inlet of the second vaporizer, respectively.

5. The storage tank cold box system for liquid hydrogen pump supply according to claim 4, characterized in that, The safety venting unit also includes a first rupture disc, a first safety valve, a three-way valve, a second rupture disc, and a second safety valve. The third branch of the second outlet at the top of the liquid hydrogen storage tank is connected to the three-way valve. One end of the three-way valve is connected in series with the first safety valve and the first rupture disc, and the other end is connected in series with the second safety valve and the second rupture disc. Both the first safety valve and the second safety valve are connected to the second vaporizer and then reheated before entering the venting tower for discharge.

6. The storage tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that, It also includes a purging unit, which includes a purging regulating valve. The purging regulating valve is connected to the bottom first inlet end and the bottom third outlet end of the liquid hydrogen storage tank, respectively. An explosion-proof safety device is connected to the outer shell of the cold box. A vacuum valve and a vacuum measuring valve are connected to the cold box, and the vacuum measuring valve is connected to a vacuum gauge tube.

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