A liquid hydrogen storage tank

Abstract

The application provides a liquid hydrogen storage tank, which comprises a storage tank body for storing liquid hydrogen raw materials and a flow guide device, wherein the flow guide device comprises a plurality of liquid conveying assemblies which are arranged at intervals in the circumferential direction of the storage tank body, the liquid inlet end of the liquid conveying assembly is communicated with the lower part of the storage tank body, and the liquid outlet end of the liquid conveying assembly is connected with the upper part of the storage tank body, so as to guide the liquid hydrogen raw materials in the lower part of the storage tank body to the upper part of the storage tank body, and a normal hydrogen to para hydrogen conversion catalyst is arranged in at least one liquid conveying assembly for converting normal hydrogen into para hydrogen. The application is advantageous in maintaining the balance of normal hydrogen and para hydrogen components in the inside of the storage tank body, guiding the heat released by the conversion to the outside of the storage tank body, reducing the heat leakage and improving the safety performance of the liquid hydrogen storage tank by arranging the liquid conveying assemblies capable of guiding the liquid hydrogen in the lower part of the storage tank body to the upper part of the storage tank body on the outer wall of the liquid hydrogen storage tank body and arranging the normal hydrogen to para hydrogen conversion catalyst in at least one liquid conveying assembly.

Description

Technical Field

[0001] This invention relates to the field of cryogenic liquid storage technology, and in particular to a liquid hydrogen storage tank. Background Technology

[0002] In the process of producing hydrogen through cryogenic liquefaction, liquid hydrogen exists in two molecular states: orthohydrogen and parahydrogen. If the insulation effect is not good, the composition of orthohydrogen and parahydrogen will change. Since the conversion process of orthohydrogen and parahydrogen involves heat of conversion and heat of vaporization, it is necessary to adopt reasonable technology to quickly remove the heat, thereby ensuring that the orthohydrogen and parahydrogen are in a stable state.

[0003] Specifically, when liquid hydrogen is stored in a tank, if the liquid hydrogen is stored in the tank for too long, some of the liquid hydrogen will be converted into gaseous hydrogen due to heat leakage, releasing heat and forming gaseous hydrogen on the upper part of the tank. This will cause the hydrogen to separate into liquid and gas phases, which will increase the pressure inside the tank and easily lead to an overpressure accident.

[0004] In addition, dead zones exist at the bottom of the tank during routine operations such as liquid hydrogen input and output, which can affect the effective storage volume of the tank.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome at least some of the shortcomings of the prior art and provide a liquid hydrogen storage tank. By setting a liquid delivery component on the outer wall of the liquid hydrogen storage tank body that can guide the liquid hydrogen in the lower part of the storage tank body to the upper part, and setting a positive and negative hydrogen conversion catalyst for converting positive hydrogen to negative hydrogen in at least one liquid delivery component, it is beneficial to maintain the balance of positive and negative hydrogen components inside the storage tank body, and guide the heat released by the conversion to the outside of the storage tank body, reduce heat leakage, and improve the safety performance of the liquid hydrogen storage tank.

[0007] To solve the above-mentioned technical problems, the present invention provides a liquid hydrogen storage tank, comprising:

[0008] The storage tank body is used to store liquid hydrogen feedstock;

[0009] The diversion device includes multiple liquid delivery components spaced apart circumferentially along the tank body. The inlet end of each liquid delivery component is connected to the lower part of the tank body, and the outlet end of each liquid delivery component is connected to the upper part of the tank body. It is used to divert liquid hydrogen feedstock from the lower part of the tank body to the upper part of the tank body. At least one liquid delivery component is provided with a positive and negative hydrogen conversion catalyst for converting positive hydrogen into negative hydrogen.

[0010] In some embodiments, each of the infusion components includes a first connecting tube, a second connecting tube, and a delivery tube;

[0011] Multiple first connecting pipes are installed at intervals along the circumference of the tank body on the lower side wall of the tank body and communicate with its interior;

[0012] Multiple second connecting pipes are installed at intervals along the circumference of the tank body on the upper side wall of the tank body and communicate with its interior;

[0013] Multiple delivery pipes are respectively connected to multiple first connecting pipes and multiple second connecting pipes in a one-to-one correspondence;

[0014] The positive and negative hydrogen conversion catalyst is filled in at least one of the first and / or second connecting pipes of the infusion assembly.

[0015] In some embodiments, each of the delivery tubes includes a suction tube, a delivery tube, and a power unit;

[0016] The suction tube is connected to the first connecting tube, and the infusion tube is connected to the second connecting tube;

[0017] The power unit is located between the suction pipe and the delivery pipe, and is fixedly connected to the side wall of the storage tank body.

[0018] In some embodiments, the second connecting pipe is a bent pipe structure, wherein one end of the second connecting pipe located inside the tank body faces the bottom of the tank body.

[0019] In some embodiments, the liquid hydrogen storage tank also includes a stirring device;

[0020] The stirring device includes a stirring assembly and a drive unit for driving the stirring assembly to rotate. The stirring assembly is located inside the storage tank body, and the drive unit is located outside the storage tank body.

[0021] In some embodiments, the stirring assembly includes a stirring shaft connected to the drive shaft of the drive unit and at least one impeller disposed on the stirring shaft.

[0022] In some embodiments, a double-layered cavity is provided at the bottom of the storage tank body, and a cryogenic heat exchange device is provided in the double-layered cavity for cryogenic heat exchange of the liquid hydrogen raw material stored inside the storage tank body.

[0023] In some embodiments, the cryogenic heat exchange device includes at least one set of cryogenic heat exchange coils, which are filled with one or more of cryogenic helium, cryogenic hydrogen, and cryogenic nitrogen.

[0024] In some embodiments, the liquid hydrogen storage tank also includes a liquid outlet structure;

[0025] The liquid outlet structure includes a liquid outlet pipe and a filter;

[0026] The outlet pipe is installed at the lower part of the storage tank body, and a control valve is provided on the outlet pipe;

[0027] The filter includes a filter tube and a filter screen disposed on the filter tube, and the filter tube is detachably connected to the liquid outlet tube.

[0028] In some embodiments, the liquid hydrogen storage tank also includes a liquid inlet structure;

[0029] The liquid inlet structure includes a liquid inlet pipe and a sealing cap;

[0030] The inlet pipe is installed on the top of the storage tank body, and the sealing cap is detachably and sealingly connected to the inlet pipe.

[0031] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art.

[0032] (1) The liquid hydrogen storage tank provided by the present invention provides a liquid delivery component on the outer wall of the liquid hydrogen storage tank body that can guide the liquid hydrogen in the lower part of the storage tank body to the upper part, and provides a positive and negative hydrogen conversion catalyst for converting positive hydrogen to negative hydrogen in at least one liquid delivery component, which is beneficial to maintaining the balance of positive and negative hydrogen components inside the storage tank body, and guiding the heat released by the conversion to the outside of the storage tank body, reducing heat leakage and improving the safety performance of the liquid hydrogen storage tank.

[0033] (2) The liquid hydrogen storage tank provided by the present invention facilitates the installation of the intermediate hydrogen conversion catalyst by filling the intermediate hydrogen conversion catalyst into the first connecting pipe and / or the second connecting pipe provided on the tank body.

[0034] (3) The liquid hydrogen storage tank provided by the present invention sets the end of the second connecting pipe inside the storage tank body to face the bottom of the storage tank body, so that the liquid hydrogen raw material entering the storage tank body through the second connecting pipe flows vertically downward, preventing the liquid hydrogen raw material from splashing.

[0035] (4) The liquid hydrogen storage tank provided by the present invention can stir the liquid hydrogen raw material stored inside the tank body by setting a stirring device, and at the same time, combined with the flow guiding device, the liquid hydrogen raw material at the bottom is transported to the upper end of the tank body to prevent excessive heat generation due to the conversion of positive and negative liquid hydrogen caused by long-term tank heat leakage, reduce the phenomenon of tank overpressure caused by excessive vapor hydrogen evaporation of liquid hydrogen, and also prevent the formation of dead zone deposition at the bottom of the tank due to excessive storage time of liquid hydrogen raw material.

[0036] (5) The liquid hydrogen storage tank provided by the present invention improves the heat exchange efficiency by setting a double-layer cavity at the bottom of the storage tank body and setting a low-temperature heat exchange device in the double-layer cavity for low-temperature heat exchange of the liquid hydrogen raw material stored inside the storage tank body, which is beneficial to maintaining the temperature of the liquid hydrogen raw material and increasing its fluidity, thereby increasing the effective flow volume of the storage tank body.

[0037] (6) The liquid hydrogen storage tank provided by the present invention has a filter that can be detachably connected to the liquid outlet pipe, making installation and disassembly simple and quick, and easy to clean and replace. Attached Figure Description

[0038] The accompanying drawings, as part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention, but do not constitute an undue limitation of the invention. Obviously, the drawings described below are merely some embodiments, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0039] Figure 1 This is a partial structural schematic diagram of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0040] Figure 2 This is another schematic diagram of a partial structure of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the structure of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0042] Figure 4 and Figure 5 This is a schematic diagram of the structure of a filter for a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0043] Figure 6 This is a schematic diagram of the delivery pipe of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0044] Figure 7 This is a schematic diagram of the structure of the second connecting pipe of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0045] Figure 8 This is a schematic diagram of the internal structure of a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0046] Figure 9 This is a schematic diagram of the structure of a stirring device for a liquid hydrogen storage tank according to an exemplary embodiment of the present invention;

[0047] Figure 10This is a schematic diagram of the structure of a cryogenic heat exchange device for a liquid hydrogen storage tank according to an exemplary embodiment of the present invention.

[0048] In the diagram: 100, liquid hydrogen storage tank;

[0049] 110. Tank body; 111. Tank body; 112. Tank cover; 113. Interlayer cavity;

[0050] 120. Liquid inlet structure; 121. Liquid inlet pipe; 122. Sealing cap; 123. Control handle;

[0051] 130. Liquid outlet structure; 131. Liquid outlet pipe; 132. Filter; 1321. Filter tube; 1322. Filter screen; 133. Control valve;

[0052] 140. Flow guiding device; 141. Infusion assembly; 142. First connecting pipe; 143. Second connecting pipe; 144. Delivery pipe; 1441. Suction pipe; 1442. Infusion pipe; 1443. Power unit; 1444. Mounting plate; 1445. Flange;

[0053] 150. Stirring device; 151. Stirring assembly; 1511. Stirring shaft; 1512. Impeller; 15121. Collar; 15122. Stirring blades; 152. Drive unit;

[0054] 160. Low-temperature heat exchange device; 161. Low-temperature heat exchange coil.

[0055] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0057] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0058] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0059] As described in the background art, in the liquid hydrogen storage tanks of the related art, liquid ortho- and para-hydrogen are stored in the tank. If the liquid hydrogen is stored in the tank for too long, heat leakage will cause some of the ortho- and para-hydrogen in the liquid hydrogen to be converted, releasing heat and forming gaseous hydrogen on the upper part of the tank, which will lead to the separation of hydrogen gas and liquid, and thus increase the pressure in the tank, which can easily lead to overpressure accidents.

[0060] To address the aforementioned problems, this invention provides a liquid hydrogen storage tank, comprising a tank body and a flow guiding device. The tank body stores liquid hydrogen feedstock. The flow guiding device includes multiple liquid delivery components spaced circumferentially along the tank body. The inlet end of each liquid delivery component is connected to the lower part of the tank body, and the outlet end is connected to the upper part of the tank body, for guiding the liquid hydrogen feedstock from the lower part of the tank body to the upper part. At least one liquid delivery component contains a positive and negative hydrogen conversion catalyst for converting positive hydrogen to negative hydrogen. This design helps maintain the balance of positive and negative hydrogen components inside the tank body and guides the heat released during conversion to the outside of the tank body, reducing heat leakage and improving the safety performance of the liquid hydrogen storage tank.

[0061] The preferred technical solution of the liquid hydrogen storage tank of the present invention is described below with reference to the accompanying drawings.

[0062] Figure 1 and Figure 2 A partial structure of a liquid hydrogen storage tank 100 provided according to an exemplary embodiment of the present invention is shown. Figure 3 The structure of the tank body 111 of a liquid hydrogen storage tank 100 according to an exemplary embodiment of the present invention is shown.

[0063] like Figures 1 to 3 As shown, the liquid hydrogen storage tank 100 includes a tank body 110 for storing liquid hydrogen feedstock and an outer container (not shown) disposed outside the tank body 110, with a vacuum insulation interlayer formed between the outer container and the tank body 110. Furthermore, multiple layers of insulation material can be provided on the outer wall of the tank body 110 to reduce heat leakage. It should be noted that the liquid hydrogen storage tank 100 provided by this invention is a large-scale underground storage tank specifically for liquid hydrogen.

[0064] In some embodiments, the storage tank body 110 includes a tank body 111 and a tank cover 112 installed on the top of the tank body 111. The tank cover 112 is provided with a liquid inlet structure 120 for injecting liquid hydrogen raw material into the storage tank body 110. The liquid inlet structure 120 includes a liquid inlet pipe 121, a sealing cover 122 and a control handle 123. The liquid inlet pipe 121 is vertically fixed on the tank cover 112 and communicates with the inside of the tank body 111. The sealing cover 122 is rotatably connected to the upper opening of the liquid inlet pipe 121. The control handle 123 is installed on the sealing cover 122.

[0065] It should be noted that when using the liquid inlet structure 120, the sealing cover 122 can be opened by controlling the handle 123 to inject liquid hydrogen raw material into the tank 111 from the liquid inlet pipe 121 for storage. After complete injection, the sealing cover 122 is closed to seal the liquid inlet pipe 121.

[0066] In some embodiments, the lower part of the tank body 111 is provided with a liquid outlet structure 130 for discharging the liquid hydrogen raw material stored inside the storage tank body 110. The liquid outlet structure 130 includes a liquid outlet pipe 131 and a filter 132. The liquid outlet pipe 131 is installed at the lower part of the storage tank body 110, and a control valve 133 is provided on the liquid outlet pipe 131. The filter 132 includes a filter pipe 1321 and a filter screen 1322 disposed on the filter pipe 1321. (Refer to...) Figure 4 and Figure 5 As shown, the filter tube 1321 is detachably connected to the liquid outlet tube 131, and the installation and disassembly are simple and quick, making it easy to clean and replace.

[0067] It should be noted that when the liquid hydrogen raw material stored inside the tank 111 needs to be used, the liquid outlet pipe 131 can be opened through the control valve 133, and the liquid hydrogen raw material stored inside the tank 111 can be discharged from the liquid outlet pipe 131 and collected.

[0068] like Figure 4 and Figure 5 As shown, when installing filter 132, filter screen 1322 is installed on the end of filter tube 1321 away from outlet tube 131, and filter tube 1321 is sleeved onto outlet tube 131 and threadedly connected thereto. It is understood that filter screen 1322 should be made of a material suitable for use in low-temperature environments.

[0069] Refer again Figure 1 and Figure 2The liquid hydrogen storage tank 100 also includes a flow guiding device 140 located in a vacuum insulation jacket. The flow guiding device 140 includes a plurality of liquid delivery assemblies 141 arranged circumferentially along the tank body 110. The inlet end of the liquid delivery assembly 141 is connected to the lower part of the tank body 110, and the outlet end of the liquid delivery assembly 141 is connected to the upper part of the tank body 110. It is used to guide the liquid hydrogen raw material in the lower part of the tank body 110 to the upper part of the tank body 110. At least one liquid delivery assembly 141 is provided with a positive and negative hydrogen conversion catalyst for converting positive hydrogen into negative hydrogen.

[0070] Specifically, after a certain period of time, some heat inevitably leaks into the liquid hydrogen feedstock in the storage tank 110. As a result, low-temperature hydrogen gas appears at the top of the tank. This low-temperature hydrogen gas, at around 20K, transforms into some liquid hydrogen and a small amount of gaseous hydrogen. With continued heat leakage, a small portion of secondary hydrogen slowly converts into orthohydrogen, causing an imbalance in the ratio of secondary to orthohydrogen in the liquid hydrogen feedstock within the tank 110. This prevents the orthohydrogen and secondary hydrogen from maintaining a stable state. If the orthohydrogen and secondary hydrogen cannot maintain a stable state—that is, when the secondary hydrogen content is less than the content of secondary hydrogen in the equilibrium hydrogen—orthohydrogen will spontaneously convert to secondary hydrogen. This conversion is an isomerization reaction between two quantum states and is exothermic. Although this process is slow, the heat of conversion is higher than the latent heat of vaporization of liquid hydrogen, leading to the evaporation of liquid hydrogen. This undoubtedly causes the liquid hydrogen feedstock to vaporize and increases the energy consumption for reliquefaction. In the above-described solution of the present invention, by providing a liquid delivery assembly 141 on the outer wall of the liquid hydrogen storage tank 100 body to guide the liquid hydrogen from the lower part of the storage tank body 110 to the upper part, and by providing a positive and negative hydrogen conversion catalyst for converting positive hydrogen to negative hydrogen in at least one liquid delivery assembly 141, the unstable positive hydrogen is converted into negative hydrogen during the process of guiding the liquid hydrogen from the lower part of the storage tank body 110 to the upper part. This helps maintain the balance of positive and negative hydrogen components inside the storage tank body 110 and prevents the spontaneous conversion of positive hydrogen to negative hydrogen inside the storage tank body 110. Moreover, by providing the positive and negative hydrogen conversion catalyst in the liquid delivery assembly 141, the heat released during the conversion can be guided to the outside of the storage tank body 110, reducing heat leakage and improving the safety performance of the liquid hydrogen storage tank 100.

[0071] In addition, placing the flow guiding device 140 in the vacuum insulation jacket is beneficial for absorbing the heat released during the conversion of orthohydrogen to parahydrogen and maintaining a stable low temperature for the catalytic conversion of orthohydrogen and parahydrogen.

[0072] As an example, the flow guiding device 140 includes four to six infusion assemblies 141 evenly spaced along the circumference of the tank body 110. Optionally, each infusion assembly 141 includes a first connecting pipe 142, a second connecting pipe 143, and a delivery pipe 144; a plurality of first connecting pipes 142 are installed at intervals along the circumference of the tank body 110 below the side wall of the tank body 110 and communicate with its interior; a plurality of second connecting pipes 143 are installed at intervals along the circumference of the tank body 110 above the side wall of the tank body 110 and communicate with its interior; a plurality of delivery pipes 144 are respectively connected to a plurality of first connecting pipes 142 and a plurality of second connecting pipes 143 in a one-to-one correspondence; the secondary hydrogen conversion catalyst is filled in at least one of the first connecting pipes 142 and / or second connecting pipes 143 of the infusion assembly 141.

[0073] Specifically, multiple first connecting pipes 142 are located on the side wall of the tank body 110 near the bottom; multiple second connecting pipes 143 are located on the side wall of the tank body 110 near the top wall, both communicating with the interior of the tank body 110. The n- and tert-hydrogen conversion catalyst can be filled into feasible first connecting pipes 142 and second connecting pipes 143 as needed. For example, the aforementioned n- and tert-hydrogen conversion catalyst can be filled into the first connecting pipes 142 and second connecting pipes 143 of each infusion assembly 141, or selectively into the first connecting pipes 142 and second connecting pipes 143 of several infusion assemblies 141. Alternatively, the aforementioned n- and tert-hydrogen conversion catalyst can be filled into each or any of the first connecting pipes 142 or second connecting pipes 143 of the infusion assembly 141.

[0074] In the above scheme, the secondary hydrogen conversion catalyst is filled into the first connecting pipe 142 and / or the second connecting pipe 143 provided on the storage tank body 110, which facilitates the installation and replacement of the secondary hydrogen conversion catalyst.

[0075] It should be noted that the catalyst used for the n-parahydroconversion can be any catalyst commonly used in the field, and this invention does not impose any limitations on it. As an example, the n-parahydroconversion catalyst is a substance formed by sintering at least one non-metallic compound selected from phosphoric acid, ammonium chloride, ammonium fluoride, and hydrofluoric acid, and metal oxides such as iron, chromium, copper, ruthenium, molybdenum, nickel, or manganese, using at least one of molecular sieves, alumina, silica, activated carbon, and titanium dioxide as a support.

[0076] Figure 6 A partial structure of the delivery pipe 144 of a liquid hydrogen storage tank 100 provided according to an exemplary embodiment of the present invention is shown.

[0077] like Figure 6As shown, each of the delivery pipes 144 includes a suction pipe 1441, a delivery pipe 1442, and a power unit 1443; the suction pipe 1441 is connected to the first connecting pipe 142, and the delivery pipe 1442 is connected to the second connecting pipe 143; the power unit 1443 is disposed between the suction pipe 1441 and the delivery pipe 1442, and is fixedly connected to the side wall of the storage tank body 110.

[0078] Optionally, the inlet end of the suction pipe 1441 is connected to the first connecting pipe 142 via a flange 1445, and the outlet end of the delivery pipe 1442 is connected to the second connecting pipe 143 via a flange 1445. As an example, the power unit 1443 is a cryogenic submersible pump; the outlet end of the suction pipe 1441 is connected to the inlet of the power unit 1443, and the inlet end of the delivery pipe 1442 is connected to the outlet of the power unit 1443. The power unit 1443 is fixed to the side wall of the storage tank body 110 via a mounting plate 1444. The power unit 1443 uses the suction pipe 1441 to generate suction at the first connecting pipe 142, drawing liquid hydrogen feedstock from the bottom of the storage tank body 110. The liquid hydrogen feedstock is then guided from the second connecting pipe 143 to the upper end of the storage tank body 110 via the delivery pipe 1442. Simultaneously, the positive hydrogen in the liquid hydrogen feedstock is converted to secondary hydrogen under the catalytic action of the positive and secondary hydrogen conversion catalyst.

[0079] Figure 7 A schematic diagram of the structure of the second connection pipe 143 of a liquid hydrogen storage tank 100 according to an exemplary embodiment of the present invention is shown.

[0080] like Figure 7 As shown, the second connecting pipe 143 is a bent pipe structure, wherein one end of the second connecting pipe 143 located inside the storage tank body 110 faces the bottom of the storage tank body 110. This ensures that the liquid hydrogen raw material entering the storage tank body 110 through the second connecting pipe 143 flows vertically downwards, preventing splashing of the liquid hydrogen raw material.

[0081] Figure 8 The internal structure of a liquid hydrogen storage tank 100 according to an exemplary embodiment of the present invention is shown; Figure 9 The structure of a stirring device 150 for a liquid hydrogen storage tank 100 according to an exemplary embodiment of the present invention is shown.

[0082] like Figure 8 and Figure 9 As shown, the liquid hydrogen storage tank 100 also includes a stirring device 150, which includes a stirring assembly 151 and a driving unit 152 for driving the stirring assembly 151 to rotate. The stirring assembly 151 is located inside the storage tank body 110, and the driving unit 152 is located outside the storage tank body 110.

[0083] Optionally, the stirring assembly 151 includes a stirring shaft 1511 connected to the drive shaft of the drive unit 152 and at least one impeller 1512 disposed on the stirring shaft 1511.

[0084] Specifically, the drive unit 152 is fixedly mounted on the tank cover 112, and at least one impeller 1512 is disposed on the stirring shaft 1511 near its lower end. The impeller 1512 includes a collar 15121 fixedly sleeved on the stirring shaft 1511 and a plurality of stirring blades 15122 arranged around and fixedly mounted on the collar 15121. The drive shaft of the drive unit 152 drives the stirring shaft 1511 to rotate, thereby driving the stirring blades 15122 on the collar 15121 to stir the liquid hydrogen feedstock at the bottom of the tank 111.

[0085] In detail, as described above, under the influence of heat leakage, the secondary hydrogen in the storage tank 110 will slowly turn into orthohydrogen, causing an imbalance in the ratio of secondary hydrogen to orthohydrogen in the liquid hydrogen feedstock in the storage tank 110. The impact of heat leakage on the liquid hydrogen feedstock at higher liquid levels in the storage tank 110 is greater than that on the liquid hydrogen feedstock at lower liquid levels. In other words, the imbalance in the ratio of orthohydrogen to secondary hydrogen in the liquid hydrogen feedstock at higher liquid levels in the storage tank 110 is greater than that in the liquid hydrogen feedstock at lower liquid levels in the storage tank 110. Based on this, the present invention equips the liquid hydrogen storage tank 100 with a stirring device 150 to allow the liquid hydrogen feedstock in the storage tank 110 to flow, which helps to restore the orthohydrogen, after endothermic changes, to a stable secondary hydrogen state.

[0086] In the above scheme, by setting up a stirring device 150, the liquid hydrogen raw material stored inside the storage tank body 110 can be stirred. At the same time, combined with the flow guiding device 140, the liquid hydrogen raw material at the bottom is transported to the upper end of the storage tank body 110. This prevents excessive heat generation due to heat leakage from the tank body 111 over a long period of time, which would lead to the conversion of the positive and negative liquid hydrogen. It also reduces the phenomenon of overpressure in the tank body 111 caused by excessive evaporation of gaseous hydrogen from the liquid hydrogen. Furthermore, it can prevent the formation of dead zones and sedimentation at the bottom of the tank due to excessive storage time of the liquid hydrogen raw material.

[0087] It should be noted that the impeller 1512 and the stirring shaft 1511 need to be made of materials suitable for use in low-temperature environments.

[0088] In some embodiments, a double-walled cavity 113 is provided at the bottom of the storage tank body 110, and a cryogenic heat exchange device 160 is provided in the double-walled cavity 113 for cryogenic heat exchange of the liquid hydrogen raw material stored inside the storage tank body 110. This can improve heat exchange efficiency, help maintain the temperature of the liquid hydrogen raw material and increase its fluidity, thereby increasing the effective flow volume of the storage tank body 110.

[0089] Figure 10 The structure of a cryogenic heat exchange device 160 for a liquid hydrogen storage tank 100 according to an exemplary embodiment of the present invention is shown.

[0090] like Figure 10 As shown, the cryogenic heat exchange device 160 includes at least one set of cryogenic heat exchange coils 161, which are filled with one or more of cryogenic helium, cryogenic hydrogen, and cryogenic nitrogen.

[0091] It should be noted that the cryogenic heat exchange coil 161 is also connected to a heat exchange medium source that supplies it with cryogenic heat exchange medium. When the temperature of the cryogenic medium such as cryogenic helium, cryogenic hydrogen or cryogenic nitrogen in the cryogenic heat exchange coil 161 does not meet the conditions for maintaining the temperature of the liquid hydrogen feedstock, the cryogenic medium in the cryogenic heat exchange coil 161 should be replaced in a timely manner.

[0092] The following reference Figures 1 to 10 The working process of the liquid hydrogen storage tank 100 provided in an exemplary embodiment of the present invention is described.

[0093] a. First, install and fix the storage tank body 110. After the storage tank body 110 is installed and fixed, the sealing cover 122 can be opened by controlling the handle 123. Liquid hydrogen raw material is injected into the interior of the storage tank body 110 from the liquid inlet pipe 121 for storage. After complete injection, close the sealing cover 122 to seal the liquid inlet pipe 121 and store the liquid hydrogen raw material.

[0094] b. The drive unit 152 drives the stirring shaft 1511 to rotate, thereby driving the stirring blades 15122 on the collar 15121 to stir the liquid hydrogen raw material at the bottom of the storage tank body 110. The power unit 1443 is fixed to the side wall of the tank body 111 through the mounting plate 1444. The power unit 1443 causes the first connecting pipe 142 to generate suction through the liquid inlet pipe 121 to draw the liquid hydrogen raw material at the bottom of the storage tank body 110. Then, the liquid hydrogen raw material at the bottom is discharged from the second connecting pipe 143 to the upper end of the storage tank body 110 through the liquid delivery pipe 1442. The main purpose is to stir the liquid hydrogen raw material stored inside the storage tank body 110 for a long time. At the same time, the positive hydrogen in the liquid hydrogen raw material is converted into secondary hydrogen under the catalytic action of the positive and secondary hydrogen conversion catalyst, maintaining the balance of positive and secondary hydrogen components inside the storage tank body 110.

[0095] c. The cryogenic heat exchange coil 161 located in the bottom interlayer cavity of the storage tank body 110 heats the bottom of the storage tank body 110 through built-in cryogenic helium heat exchange, so as to maintain the temperature of liquid hydrogen and increase its fluidity.

[0096] d. When it is necessary to use the liquid hydrogen raw material stored inside the storage tank body 110, the liquid outlet pipe 131 can be opened through the control valve 133, and the liquid hydrogen raw material stored inside the storage tank body 110 can be discharged from the liquid outlet pipe 131 and collected.

[0097] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A liquid hydrogen storage tank, characterized in that, include: The storage tank body is used to store liquid hydrogen feedstock; An outer container is disposed on the outside of the storage tank body, and a vacuum insulation interlayer is formed between the outer container and the storage tank body; A flow guiding device is disposed in the vacuum insulation jacket. The flow guiding device includes a plurality of liquid delivery components spaced apart along the circumference of the tank body. The inlet end of the liquid delivery component is connected to the lower part of the tank body, and the outlet end of the liquid delivery component is connected to the upper part of the tank body. It is used to guide the liquid hydrogen raw material in the lower part of the tank body to the upper part of the tank body. At least one liquid delivery component is provided with a positive and secondary hydrogen conversion catalyst for converting positive hydrogen into secondary hydrogen. A stirring device, comprising a stirring assembly and a drive unit for driving the stirring assembly to rotate, wherein the stirring assembly is located inside the storage tank body and the drive unit is located outside the storage tank body.

2. The liquid hydrogen storage tank according to claim 1, characterized in that, Each of the infusion components includes a first connecting tube, a second connecting tube, and a delivery tube; Multiple first connecting pipes are installed at intervals along the circumference of the tank body on the lower side wall of the tank body and communicate with its interior; Multiple second connecting pipes are installed at intervals along the circumference of the tank body on the upper side wall of the tank body and communicate with its interior; Multiple delivery pipes are respectively connected to multiple first connecting pipes and multiple second connecting pipes in a one-to-one correspondence; The positive and negative hydrogen conversion catalyst is filled in at least one of the first and / or second connecting pipes of the infusion assembly.

3. The liquid hydrogen storage tank according to claim 2, characterized in that, Each of the delivery tubes includes a suction tube, a delivery tube, and a power unit; The suction tube is connected to the first connecting tube, and the infusion tube is connected to the second connecting tube; The power unit is located between the suction pipe and the delivery pipe, and is fixedly connected to the side wall of the storage tank body.

4. The liquid hydrogen storage tank according to claim 2, characterized in that, The second connecting pipe is a bent pipe structure, wherein one end of the second connecting pipe located inside the tank body faces the bottom of the tank body.

5. The liquid hydrogen storage tank according to any one of claims 1 to 4, characterized in that, The stirring assembly includes a stirring shaft connected to the drive shaft of the drive unit and at least one impeller disposed on the stirring shaft.

6. The liquid hydrogen storage tank according to claim 5, characterized in that, The bottom of the storage tank body is provided with a double-layer cavity, and a low-temperature heat exchange device is provided in the double-layer cavity for low-temperature heat exchange of the liquid hydrogen raw material stored inside the storage tank body.

7. The liquid hydrogen storage tank according to claim 6, characterized in that, The cryogenic heat exchange device includes at least one set of cryogenic heat exchange coils, which are filled with one or more of cryogenic helium, cryogenic hydrogen, and cryogenic nitrogen.

8. The liquid hydrogen storage tank according to any one of claims 1 to 4, characterized in that, It also includes the liquid outlet structure; The liquid outlet structure includes a liquid outlet pipe and a filter; The outlet pipe is installed at the lower part of the storage tank body, and a control valve is provided on the outlet pipe; The filter includes a filter tube and a filter screen disposed on the filter tube, and the filter tube is detachably connected to the liquid outlet tube.

9. The liquid hydrogen storage tank according to any one of claims 1 to 4, characterized in that, It also includes the liquid inlet structure; The liquid inlet structure includes a liquid inlet pipe and a sealing cap; The inlet pipe is installed on the top of the storage tank body, and the sealing cap is detachably and sealingly connected to the inlet pipe.

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