Storage tank cold box system for liquid supply of liquid hydrogen pump

Abstract

The invention provides a storage tank cold box system for liquid supply of a liquid hydrogen pump, and particularly relates to the technical field of low-temperature tests.According to the storage tank cold box system for liquid supply of the liquid hydrogen pump, a liquid hydrogen storage tank, a pipeline, a valve, a sensor and other devices in an internal testing unit are integrated in a cold box; the problem of liquid hydrogen vaporization caused by heat leakage possibly existing in multiple device nodes can be solved, liquid hydrogen evaporation is reduced to the maximum extent, the liquid hydrogen consumption is reduced, and high safety is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of low temperature testing, and in particular to a tank cold box system for liquid hydrogen pump liquid supply. Background Art

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

[0003] Liquid hydrogen pumps and liquid hydrogen containers are the core equipment of liquid hydrogen refueling stations. Liquid hydrogen pumps, as important components for liquid hydrogen transportation applications, are mainly divided into liquid hydrogen high-pressure pumps, liquid hydrogen tanks and large-flow liquid hydrogen centrifugal pumps. The liquid hydrogen high-pressure pump liquid hydrogen tank has a maximum pressure of up to 100MPa and can be filled with high-pressure hydrogen; liquid hydrogen centrifugal pumps are used to fill liquid hydrogen with a maximum flow rate of up to 12L / s. Existing liquid hydrogen pumps are mainly non-immersed. With the development of technology, immersed liquid hydrogen pumps have the characteristics of low static evaporation rate, and have obvious advantages over non-immersed types in vaporization suppression and rapid startup. The immersed structure can provide better inlet supercooling for the liquid hydrogen pump, and after long-term static storage, there is no need to pre-cool the liquid hydrogen pump system.

[0004] In the prior art, most liquid hydrogen pump performance test platforms are open systems, which make it difficult to eliminate the impact of tank heat leakage on pump characteristics, which can lead to problems of heat leakage and liquid hydrogen vaporization.

[0005] In view of this, the present invention provides a storage tank cold box system capable of reducing heat leakage. Summary of the invention

[0006] In order to solve the problems of heat leakage and liquid hydrogen vaporization that are prone to occur in existing test platforms, the present invention proposes a tank cold box system for liquid supply by a liquid hydrogen pump.

[0007] The present invention is achieved through the following technical solutions:

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

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

[0010] The external test unit includes a submersible pump liquid hydrogen tank, a flow meter, a high-pressure pump liquid hydrogen tank and a second vaporizer, wherein the submersible pump liquid hydrogen tank and the high-pressure pump liquid hydrogen tank are respectively provided with a submersible pump and a high-pressure pump;

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

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

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

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

[0015] Furthermore, it also includes a release unit, which includes a flame arrester, a third check valve, a release tower and a steam trap. 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 release tower and the steam trap respectively.

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

[0017] Furthermore, the liquid hydrogen inlet is connected to the first check valve and the low-temperature filter inside the cold box in sequence, and the outlet end of the low-temperature filter is connected to the first inlet end at the bottom of the liquid hydrogen storage tank through the second stop valve and to the first inlet end at the top of the liquid hydrogen storage tank through the first stop valve, and a branch at the outlet end of the low-temperature 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 manual valve, a first pneumatic vent valve and a second pneumatic vent valve, and a first branch at the second outlet end of the top of the liquid hydrogen storage tank is respectively connected to the backup manual valve, the first pneumatic vent valve and the inlet of the second vaporizer, and a second branch at the second outlet end of the top of the liquid hydrogen storage tank is respectively connected to the second pneumatic vent valve and the inlet of the second vaporizer.

[0019] Furthermore, the safety venting unit also includes a first bursting disc, a first safety valve, a three-way valve, a second bursting disc, and a second safety valve. The third branch at the second outlet end 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 bursting disc, and the other end is connected in series with the second safety valve and the second bursting disc. The first safety valve and the second safety valve are both connected to the second vaporizer and then reheated to enter the venting tower for discharge.

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

[0021] Furthermore, a first return air stop valve and a second return air stop valve are respectively provided between the return air port of the submersible pump liquid hydrogen pool and the return air port of the high-pressure pump liquid hydrogen pool to the second inlet end at the top of the liquid hydrogen storage tank, and a fourth regulating valve is also provided between the inlet end of the second vaporizer and the third outlet end at the bottom of the liquid hydrogen storage tank. The first return air stop valve, the second return air stop valve and the fourth regulating valve are located in the cold box.

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

[0023] Beneficial effects of the present invention:

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

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

[0026] (3) The tank cold box system for liquid hydrogen pump supply proposed in the present 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The overall structural diagram of the tank cold box system for liquid hydrogen pump supply of the present invention;

[0028] In the figure: cold box 1, liquid hydrogen storage tank 2, first pressure gauge 3, gas phase hand valve 4, balancing valve 5, liquid level gauge 6, liquid phase hand valve 7, first safety valve 8, first manual vent valve 9, first check valve 10, low temperature filter 11, first stop valve 12, second stop valve 13, first regulating valve 14, first vaporizer 15, first pneumatic vent valve 16, spare hand valve 17, second pneumatic vent valve 18, first bursting disc 19, second safety valve 20, three-way valve 21, third safety valve 22, second bursting disc 23, fourth safety valve 24, second check valve 25, second regulating valve 26, first A temperature and pressure sensor 27, a flow meter 28, an exhaust valve 29, a first return air stop valve 30, a second temperature and pressure sensor 31, a third regulating valve 32, a second return air stop valve 33, a fourth regulating valve 34, a fourth regulating valve 35, a third temperature and pressure sensor 36, a liquid hydrogen filter 37, a fifth safety valve 38, a submersible pump liquid hydrogen tank 39, a high-pressure pump liquid hydrogen tank 40, a second vaporizer 41, a flame arrester 42, a third check valve 43, a venting tower 44, a steam trap 45, a purge regulating valve 46, an explosion-proof safety device 47, a vacuum gauge 48, a vacuum measuring valve 49, and a vacuum pump 50.

[0029] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0030] In order to more clearly and completely illustrate the technical solution of the present invention, the present invention is further described below in conjunction with the accompanying drawings.

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

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

[0033] The external test unit includes a submersible pump liquid hydrogen pool 39, a flow meter 28, a high-pressure pump liquid hydrogen pool 40 and a second vaporizer 41. The submersible pump liquid hydrogen pool 39 and the high-pressure pump liquid hydrogen pool 40 are respectively provided with a submersible pump and a high-pressure pump;

[0034] The liquid hydrogen inlet is connected to the first inlet end at the bottom and the first inlet end at the top of the liquid hydrogen storage tank 2, and the third outlet end at the bottom of the liquid hydrogen storage tank 2 is respectively 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, and the outlet end of the high-pressure pump liquid hydrogen pool 40 is connected to the high-pressure vaporizer;

[0035] The second inlet end at the top of the liquid hydrogen storage tank 2 is connected to the return port of the high-pressure pump liquid hydrogen pool 40 and the return port of the submersible pump liquid hydrogen pool 39 respectively. The first return air stop valve 30 and the second return air stop valve 33 are respectively arranged between the return port of the submersible pump liquid hydrogen pool 39 and the return port of the high-pressure pump liquid hydrogen pool 40 to the second inlet end at the top of the liquid hydrogen storage tank 2. A fourth regulating valve 34 is also arranged between the inlet end of the second vaporizer 41 and the third outlet end at the bottom of the liquid hydrogen storage tank 2. The first return air stop valve 30, the second return air stop valve 33 and the fourth regulating valve 34 are located in the cold box 1;

[0036] The internal test unit includes a high-pressure pump test section and a submersible pump test section. The submersible pump test section includes: a third regulating valve 32 and a second temperature and pressure sensor 31 are sequentially arranged from the third outlet end of the bottom of the liquid hydrogen storage tank to the inlet end of the liquid hydrogen pool 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 are sequentially arranged from the liquid outlet end of the liquid hydrogen pool of the submersible pump to the second inlet end of the bottom of the liquid hydrogen storage tank; the high-pressure pump test section includes: a fourth regulating valve 35, a third temperature and pressure sensor 36, and a liquid hydrogen filter 37 are sequentially arranged from the third outlet end of the bottom of the liquid hydrogen storage tank to the inlet end of the liquid hydrogen pool of the high-pressure pump, and the outlet end of the liquid hydrogen pool of the high-pressure pump to the high-pressure vaporizer. The high-pressure pump test section and the submersible pump test section are both placed inside the cold box 1.

[0037] In this embodiment:

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

[0039] The high-pressure pump liquid hydrogen pool 40 and the submersible pump liquid hydrogen pool 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 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;

[0044] The flowmeter 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 provided in the high-pressure pump liquid hydrogen pool 40 and the submersible pump liquid hydrogen pool 39. When testing, the liquid hydrogen at the liquid hydrogen inlet is filled into the liquid hydrogen storage tank 2 through the first inlet end at the bottom and the first inlet end at the top of the liquid hydrogen storage tank 2. The liquid hydrogen in the liquid hydrogen storage tank 2 provides liquid hydrogen to the submersible pump and the high-pressure pump through the third outlet end at the bottom. For the submersible pump test, the liquid hydrogen flows out through the third outlet end at the bottom of the liquid hydrogen storage tank, passes through the third regulating valve 32 and the second temperature and pressure sensor 31 in turn, enters the submersible pump liquid hydrogen pool 39, and the liquid level of the submersible pump pool reaches about 90%, and the third regulating valve 32 is closed; for the high-pressure pump test, the liquid hydrogen flows out through the third outlet end at the bottom of the liquid hydrogen storage tank, passes through the fourth regulating valve 35 and the third temperature and pressure sensor 36 in turn, enters the high-pressure pump liquid hydrogen pool 40, and the liquid level of the high-pressure pump pool reaches about 90%, and the fourth regulating valve 35 is closed. After completing the filling of the two pump pools, start the submersible pump and the high-pressure pump, and record the data of the submersible pump and the high-pressure pump by changing the pump speed, as well as the first temperature and pressure sensor 27, the second temperature and pressure sensor 31, the flow meter 28, 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 heat leakage at multiple device nodes that may cause liquid hydrogen vaporization, minimize liquid hydrogen evaporation, save liquid hydrogen usage and have high safety.

[0045] In one embodiment, the liquid outlet pipe of the submersible pump is connected to the cold box 1 through a Bayonet low-temperature joint and back to the liquid phase space of the liquid hydrogen storage tank 2 to form a cycle to reduce the consumption of liquid hydrogen. Furthermore, a booster unit is also included, and the booster unit includes a first vaporizer 15 and a first regulating valve 14. The second outlet end at the bottom of the liquid hydrogen storage tank 2 is connected to the first regulating valve 14, the first vaporizer 15 and the third inlet end at the top of the liquid hydrogen storage tank 2 in sequence.

[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 arranged outside the cold box 1. The first vaporizer 15 can perform convection heat exchange with the air, and can also perform heat exchange with other gases or liquids. The liquid hydrogen enters the second vaporizer 15 through the first regulating valve 14, and is then converted into hydrogen 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 release unit, which includes a flame arrester 42, a third check valve 43, a release tower 44 and a steam trap 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 release tower 44 and the steam trap 45 respectively.

[0050] In this embodiment:

[0051] The discharge tower 44 is used to discharge the hydrogen after the test;

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

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

[0054] In this embodiment:

[0055] The liquid level meter 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 in the 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 meteorological manual valve 4 and the liquid phase manual valve 7 are opened, and then the pressure gauge 3 and the liquid level gauge 6 will respectively display the pressure of liquid hydrogen and the liquid level of liquid hydrogen in the liquid hydrogen storage tank 2.

[0058] Furthermore, the liquid hydrogen inlet is connected to the first check valve 10 and the low-temperature filter 11 inside the cold box 1 in sequence, and the outlet end of the low-temperature filter 11 is connected to the first inlet end at the bottom of the liquid hydrogen storage tank 2 through the second stop valve 13 and the first inlet end at the top of the liquid hydrogen storage tank 2 through the first stop valve 12. A branch at the outlet end of the low-temperature 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 discharge part of the liquid hydrogen when overpressure occurs;

[0061] The first safety valve 8 is used to actively discharge liquid hydrogen when overpressure occurs;

[0062] The low temperature filter 11 is used to filter impurities in the liquid hydrogen;

[0063] The first stop valve 13 and the second stop valve 12 are used to control the filling of liquid hydrogen;

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

[0065] In a specific embodiment, if the liquid hydrogen storage tank 2 is filled with liquid for the first time, the first stop valve 12 is closed first, and the second stop valve 13 is opened. Liquid hydrogen is slowly filled into the liquid hydrogen storage tank 2 and precooling is completed. Then the second stop valve 13 is closed, and the first stop valve 12 is opened to fill the top until the filling is completed; if it is not the first filling, when there is still some liquid hydrogen remaining in the liquid hydrogen storage tank, the first stop valve 12 and the second stop valve 13 can be opened at the same time according to the liquid level of the liquid hydrogen storage tank, and the top and bottom are filled with liquid at the same time to speed up the filling speed of liquid hydrogen. At this time, since the temperature of the liquid hydrogen entering from the top is lower than the temperature of the gas phase space in the storage tank, the gas in the gas phase space is liquefied, the pressure of the storage tank drops, and the liquid delivery speed of the liquid hydrogen is guaranteed. After the filling of the liquid hydrogen storage tank 2 is completed, the first stop valve 12 and the second stop valve 13 are closed, and the residual part of the liquid hydrogen in the pipeline between the first check valve 10 and the first stop valve 12 and the second stop 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 manual valve 17, a first pneumatic vent valve 16 and a second pneumatic vent valve 18. The first branch at the second outlet end at the top of the liquid hydrogen storage tank is respectively connected to the backup manual valve 17, the first pneumatic vent valve 16 and the inlet of the second vaporizer 41, and the second branch at the second outlet end at the top of the liquid hydrogen storage tank is respectively connected to the second pneumatic vent valve 18 and the inlet of the second vaporizer 41.

[0067] In this embodiment:

[0068] The first pneumatic vent valve 16 is a pneumatic control valve used to accurately control the exhaust pressure and flow rate;

[0069] The spare manual valve 17 is a manual switch valve, which is used in an emergency when the first pneumatic vent valve fails;

[0070] The second pneumatic vent valve is a pneumatic switch valve, which is used for automatic pressure relief when the pressure 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 backup manual valve 17 and the first pneumatic switch valve 16 can be opened to discharge hydrogen, or the pneumatic vent valve 18 can be further opened for emergency pressure relief to stabilize the pressure in the liquid hydrogen storage tank 2.

[0072] Furthermore, the safety venting unit also includes a first bursting disc 19, a first safety valve 20, a three-way valve 21, a second bursting disc 22, and a second safety valve 23. The third branch at the second outlet end of 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 bursting disc 19, and the other end is connected in series with the second safety valve 23 and the second bursting disc 22. The first safety valve 20 and the second safety valve 23 are both connected to the second vaporizer and then reheated to enter the venting tower 44 for discharge.

[0073] In this embodiment:

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

[0075] The first safety valve 20 and the first bursting disc 19, the second safety valve 23 and the second bursting disc 22 are all connected in series for automatic pressure relief; in actual operation, one is used and the other is reserved to prevent the safety valve from failing.

[0076] In a specific embodiment, the safety valve and the bursting disc are both set with pressure values ​​in advance, and are automatically opened when the pressure in the liquid hydrogen storage tank 2 exceeds the set value. 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 respectively connected to two branches, both branches are provided with safety valves and bursting discs. When the pressure in 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 discharge the pressure, or the first safety valve 20 or the second safety valve 22 can be automatically opened to complete the pressure discharge.

[0077] Furthermore, the return air port of the high-pressure pump liquid hydrogen tank 40 and the return air port of the submersible pump liquid hydrogen tank 39 are connected to the inlet end of the second vaporizer 41, and an exhaust valve 29, a fourth safety valve 24 and a fifth safety valve 38 are respectively arranged between the return air port of the submersible pump liquid hydrogen tank 39, the liquid outlet end of the submersible pump liquid hydrogen tank 39, and the return air port of the high-pressure pump liquid hydrogen tank 40 to 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 adjust the hydrogen overpressure discharge in the return air pipeline of the submersible pump;

[0081] In a specific embodiment, the exhaust valve 29 of the submersible pump return air pipeline, the safety valve 24 of the submersible pump outlet liquid pipeline, and the safety valve 38 of the high-pressure pump pipeline are all set with pipeline pressure values ​​in advance. When the pressure in the pipeline exceeds the set value, it automatically opens to discharge liquid hydrogen or low-temperature hydrogen into the second vaporizer 41 to recover cold energy.

[0082] In one embodiment, when the pressure in the liquid hydrogen storage tank 2 is too high or liquid hydrogen needs to be discharged urgently, the fourth regulating valve 34 is automatically opened, and the liquid hydrogen in the liquid hydrogen storage tank 2 is converted into hydrogen through the second vaporizer 41, and the cold energy is recovered and discharged into the discharge tower 44.

[0083] Furthermore, a first return air stop valve 30 and a second return air stop valve 33 are respectively provided between the return air port of the submersible pump liquid hydrogen pool 39 and the return air port of the high-pressure pump liquid hydrogen pool 40 to the second inlet end of the top of the liquid hydrogen storage tank 2, and a fourth regulating valve 34 is also provided 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 air stop valve 30, the second return air stop valve 33 and the fourth regulating valve 34 are located in the cold box 1.

[0084] In this embodiment:

[0085] The first gas return stop valve 30 and the second gas return stop valve 33 are used to adjust the pressure in the submersible pump liquid hydrogen tank 39 and the high-pressure pump liquid hydrogen tank 40;

[0086] In a specific embodiment, in one embodiment, liquid hydrogen may leak heat during transportation, and part of the liquid hydrogen may be converted into hydrogen. At this time, opening the first return air stop valve 30 and the second return air stop valve 33 may allow hydrogen to enter the liquid hydrogen storage tank 2. When the pressure of the liquid hydrogen storage tank 2 is too high, the fourth regulating valve 34 may be directly opened to discharge the hydrogen directly into the second vaporizer 41.

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

[0088] In this embodiment:

[0089] The vacuum valve 50 is used to vacuum the cold box 1;

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

[0091] The vacuum gauge 48 and the vacuum measuring valve 49 are used to detect the vacuum degree of the cold box 1;

[0092] In a specific embodiment, in order to ensure the purity of the gas in the pipeline, a purge unit is provided on the cold box 1 and the pipeline is purged with high-purity dry nitrogen, so that oxygen, water and other impurities in the pipeline are completely removed to ensure the cleanliness of the pipeline. The vacuum gauge 48 and the vacuum measuring valve 49 detect the vacuum degree of the cold box 1 to prevent its vacuum from deteriorating. The mechanical pump and the molecular pump evacuate the cold box 1 through the vacuum valve 50, so that the vacuum degree of the cold box 1 is better than 1×10 -2 Pa, better than 1×10 at low temperature -5 Pa.

[0093] Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims

1. A tank cold box system for liquid hydrogen pump supply, characterized in that: It includes cold box unit, internal test unit and external test unit, among which: The cold box unit comprises a cold box, and a liquid hydrogen storage tank is arranged inside the cold box; The external test unit includes a submersible pump liquid hydrogen tank, a flow meter, a high-pressure pump liquid hydrogen tank and a second vaporizer, wherein the submersible pump liquid hydrogen tank and the high-pressure pump liquid hydrogen tank are respectively provided with a submersible pump and a high-pressure pump; The liquid hydrogen inlet is connected to the first inlet end at the bottom and the first inlet end at the top of the liquid hydrogen storage tank, the third outlet end at the bottom of the liquid hydrogen storage tank is respectively connected to the inlet end of the submersible pump liquid hydrogen pool, the inlet end of the high-pressure pump liquid hydrogen pool and the inlet end of the second vaporizer, and the outlet end of the high-pressure pump liquid hydrogen pool is connected to the high-pressure vaporizer; The second inlet end at the top of the liquid hydrogen storage tank is connected to the gas return port of the high-pressure pump liquid hydrogen tank and the gas return port of the submersible pump liquid hydrogen tank respectively; The internal test unit includes the high-pressure pump test section and the submersible pump test section. The submersible pump test section includes: a third regulating valve and a second temperature and pressure sensor are sequentially arranged from the third outlet end at the bottom of the liquid hydrogen storage tank to the inlet end of the liquid hydrogen pool of the submersible pump, and a flow meter, a first temperature and pressure sensor, a second regulating valve, and a second check valve are sequentially arranged from the liquid outlet end of the liquid hydrogen pool of the submersible pump to the second inlet end at the bottom of the liquid hydrogen storage tank; the high-pressure pump test section includes: a fourth regulating valve, a third temperature and pressure sensor, and a liquid hydrogen filter are sequentially arranged from the third outlet end at the bottom of the liquid hydrogen storage tank to the inlet end of the liquid hydrogen pool of the high-pressure pump, and the liquid outlet end of the liquid hydrogen pool of the high-pressure pump to the high-pressure vaporizer. The high-pressure pump test section and the submersible pump test section are both placed inside the cold box.

2. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: It also includes a boosting unit, which includes a first vaporizer and a first regulating valve. The second outlet end at the bottom of the liquid hydrogen storage tank is connected to the first regulating valve, the first vaporizer and the third inlet end at the top of the liquid hydrogen storage tank in sequence.

3. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: It also includes a release unit, which includes a flame arrester, a third check valve, a release tower and a steam trap. 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 release tower and the steam trap respectively.

4. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: It also includes a monitoring unit, which includes a first pressure gauge, a gas phase hand valve, a balancing valve, a liquid level meter and a liquid phase hand valve. The first outlet end at the bottom 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 respectively connected to one end of the liquid level meter and one end of the balancing valve. The first outlet end at the top 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 respectively connected to the other end of the liquid level meter and the other end of the balancing valve.

5. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: The liquid hydrogen inlet is connected to the first check valve and the low-temperature filter inside the cold box in sequence, and the outlet end of the low-temperature filter is connected to the first inlet end at the bottom of the liquid hydrogen storage tank through the second stop valve and the first inlet end at the top of the liquid hydrogen storage tank through the first stop valve. A branch at the outlet end of the low-temperature filter is connected to the first manual vent valve and the first safety valve outside the cold box.

6. The 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 manual valve, a first pneumatic venting valve and a second pneumatic venting valve. The first branch at the second outlet end at the top of the liquid hydrogen storage tank is respectively connected to the backup manual valve, the first pneumatic venting valve and the inlet of the second vaporizer, and the second branch at the second outlet end at the top of the liquid hydrogen storage tank is respectively connected to the second pneumatic venting valve and the inlet of the second vaporizer.

7. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: The safety venting unit also includes a first bursting disc, a first safety valve, a three-way valve, a second bursting disc, and a second safety valve. The third branch at the second outlet end of 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 bursting disc, and the other end is connected in series with the second safety valve and the second bursting disc. The first safety valve and the second safety valve are both connected to the second vaporizer and then reheated into the venting tower for discharge.

8. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: The return air port of the high-pressure pump liquid hydrogen pool and the return air port of the submersible pump liquid hydrogen pool are connected to the inlet end of the second vaporizer, and an exhaust valve, a fourth safety valve and a fifth safety valve are respectively arranged between the return air port of the submersible pump liquid hydrogen pool, the return air 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.

9. The tank cold box system for liquid hydrogen pump supply according to claim 1, characterized in that: A first air return stop valve and a second air return stop valve are respectively arranged between the air return port of the submersible pump liquid hydrogen tank and the air return port of the high-pressure pump liquid hydrogen tank to the second inlet end at the top of the liquid hydrogen storage tank. A fourth regulating valve is also arranged between the inlet end of the second vaporizer and the third outlet end at the bottom of the liquid hydrogen storage tank. The first air return stop valve, the second air return stop valve and the fourth regulating valve are located in the cold box.

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

Images