Heat insulation system of liquid hydrogen spherical tank and liquid hydrogen spherical tank

Abstract

The utility model provides a heat insulation system of a liquid hydrogen spherical tank and the liquid hydrogen spherical tank. The heat insulation system of the liquid hydrogen spherical tank comprises a heat insulation structure, and the heat insulation structure comprises an inner tank, an outer tank, a vacuum heat insulation plate, a polyurethane plate and an elastic felt; the heat-insulating structure is divided into a first space and a second space along the thickness direction of the spherical tank; a plurality of heat insulation plate layers are installed in the first space, each heat insulation plate layer comprises a plurality of vacuum heat insulation plates, a first polyurethane plate layer is arranged between the different heat insulation plate layers, and the first polyurethane plate layer comprises a plurality of polyurethane plates; a plurality of second polyurethane plate layers are arranged in the second space, and each second polyurethane plate layer comprises a plurality of polyurethane plates; preferably, the vacuum insulated panel comprises a fumed silica core material and a 304 stainless steel composite barrier film, and the 304 stainless steel composite barrier film is coated on the surface of the core material. Due to the fact that the vacuum insulation plate structure is adopted, vacuumizing is not needed before the storage tank is used, and time cost and labor cost caused by the fact that an existing storage tank needs to be vacuumized are reduced.

Description

Technical Field

[0001] This utility model relates to the field of thermal insulation technology for large liquid hydrogen spherical tanks, specifically, to a thermal insulation system for a liquid hydrogen spherical tank and a liquid hydrogen spherical tank, particularly to a thermal insulation system for a large liquid hydrogen spherical tank and a liquid hydrogen spherical tank, and especially to a thermal insulation system with a composite thermal insulation structure and its construction method. Background Technology

[0002] To store hydrogen energy more efficiently or facilitate large-scale hydrogen transportation, hydrogen is often stored in large spherical tanks as a cryogenic liquid. The temperature difference between liquid hydrogen and the external environment can reach 270-300°C, resulting in a significant amount of heat entering the tank through its insulation structure, causing the liquid hydrogen to evaporate and resulting in energy loss. Therefore, it is necessary to install high-performance insulation materials between the inner and outer tanks of the spherical tank to reduce heat leakage.

[0003] Existing large liquid hydrogen spherical tanks typically employ stacked insulation between inner and outer tanks. Therefore, before use, the interlayer between the inner and outer tanks needs to be vacuumed to ensure the insulation effect of the spherical tank, as shown in patent documents CN116447501A and CN117386992A.

[0004] Vacuuming large liquid hydrogen storage tanks is extremely difficult and requires a lot of time and electricity. However, if the tank is not evacuated before use, the overall insulation performance of the tank cannot meet the requirements.

[0005] Therefore, how to design a storage tank that does not require vacuuming before use is a technical problem that urgently needs to be solved. Utility Model Content

[0006] In view of the deficiencies in the prior art, the purpose of this utility model is to provide an insulation system for a liquid hydrogen spherical tank and a liquid hydrogen spherical tank.

[0007] The present invention provides a heat insulation system for a liquid hydrogen spherical tank, comprising a heat insulation structure, wherein the heat insulation structure includes an inner tank, an outer tank, a vacuum heat insulation panel, a polyurethane panel, and an elastic felt.

[0008] The outer tank is fitted over the inner tank, and the vacuum insulation panel, polyurethane panel and elastic felt are all located between the outer tank and the inner tank.

[0009] The thermal insulation structure is divided into a first space and a second space along the thickness direction of the spherical tank; the outer tank is located in the first space, and the inner tank is located in the second space.

[0010] The first space is also equipped with multiple layers of insulation panels, each layer of insulation panels includes multiple vacuum insulation panels, and a first polyurethane panel layer is arranged between different layers of insulation panels, the first polyurethane panel layer includes multiple polyurethane panels.

[0011] The second space is provided with multiple layers of second polyurethane boards, each layer comprising multiple polyurethane boards;

[0012] In the second space, elastic felt is filled between different polyurethane panels.

[0013] Preferably, the vacuum insulation panel includes

[0014] A fumed silica core material is combined with a 304 stainless steel composite barrier film. The vacuum degree inside the fumed silica core material is less than 10 Pa, and the 304 stainless steel composite barrier film is coated on the surface of the core material.

[0015] Preferably, in the first space, the number of insulation board layers is 7 to 9 and the number of first polyurethane board layers is 6 to 8;

[0016] In the second space, a gap of 10 to 40 mm is provided between each polyurethane board, and the gap is used to install the elastic felt.

[0017] Preferably, the thickness of the vacuum insulation board is 30~40mm, and the vacuum insulation board and the polyurethane board are bonded together by a low-temperature adhesive layer.

[0018] Preferably, the insulation system of the liquid hydrogen spherical tank further includes polyurethane foam, which fills the installation gap between the vacuum insulation panel and the outer tank in the first space.

[0019] Preferably, the elastic felt is made of polyisocyanate and is pre-compressed to a thickness of 40-60% during installation.

[0020] Preferably, in the first space, the vacuum insulation panel and the polyurethane panel are staggered along the thickness direction, and the elastic felt is filled in the gaps created at the joints between the vacuum insulation panels and the polyurethane panels.

[0021] Preferably, in the first space, the thickness of a single polyurethane panel is 50~70 mm;

[0022] The second polyurethane board layer set in the second space 6 has 2 to 4 layers and a thickness of 80 to 100 mm.

[0023] Preferably, the thickness of the 304 stainless steel barrier film is 0.15~0.20 mm.

[0024] According to the present invention, a liquid hydrogen spherical tank is provided, and the heat insulation system of the liquid hydrogen spherical tank is adopted.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This utility model eliminates the need for vacuuming before use, reducing the time and labor costs associated with vacuuming existing storage tanks.

[0027] 2. This utility model is equipped with an elastic felt, which can compensate for the effects caused by the shrinkage of the inner tank along the thickness direction and along the circumference. Attached Figure Description

[0028] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figure 1 This is a schematic diagram of the spatial division of this utility model;

[0030] Figure 2 This is a schematic diagram of the structure of this utility model;

[0031] The diagram shows:

[0032] Detailed Implementation

[0033] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0034] This utility model provides a heat insulation system for a liquid hydrogen spherical tank, such as... Figure 1 and Figure 2 As shown, it includes a heat insulation structure, which includes an inner tank 4 and an outer tank 1, a vacuum insulation panel 2, a polyurethane panel 3, and an elastic felt 7; in a preferred embodiment, the polyurethane panel 3 is a rigid polyurethane panel.

[0035] The outer tank 1 is fitted over the inner tank 4. The vacuum insulation panel 2, polyurethane panel 3, and elastic felt 7 are all located between the outer tank 1 and the inner tank 4. The thickness of the insulation structure does not exceed 1.2 meters. The insulation structure can be divided into a first space 5 and a second space 6 along the thickness direction. The outer tank 1 is located in the first space 5, and the inner tank 4 is located in the second space 6. The first space is also equipped with multiple layers of insulation panels. Each layer of insulation panels includes multiple vacuum insulation panels 2. A first polyurethane panel layer is arranged between different layers of insulation panels. The first polyurethane panel layer includes multiple polyurethane panels 3. The vacuum insulation panels 2 and polyurethane panels 3 are staggered between each layer and are bonded with low-temperature adhesive.

[0036] The second space 6 contains multiple layers of second polyurethane panels, which can be 2 to 4 layers, specifically 3 layers. Each second polyurethane panel consists of multiple polyurethane panels 3, with elastic felt 7 filling the spaces between them. The elastic felt 7 compensates for the shrinkage and deformation of the inner tank 4 at low temperatures. In other words, each polyurethane panel 3 is spaced apart along both the thickness and circumferential directions to accommodate the elastic felt 7. The elastic felt 7 primarily compensates for the structural displacement caused by the filling of the spherical tank with liquid hydrogen. Secondly, because the elastic felt 7 is made of a material with low thermal conductivity, it provides insulation for the spherical tank. The thickness of the polyurethane panels 3 in the second space 6 is 80 to 100 mm.

[0037] The first space 5 and the second space 6 are separated by the innermost vacuum insulation panel 2. In a preferred embodiment, the polyurethane panel 3 is a prefabricated rigid polyurethane panel, and its shape is a square with a certain curvature.

[0038] The vacuum insulation panel 2 comprises a core material of fumed silica and a composite barrier film of 304 stainless steel. Preferably, the thickness of the 304 stainless steel barrier film is 0.15~0.20 mm. The vacuum degree inside the fumed silica core material is less than 10 Pa, and the 304 stainless steel composite barrier film covers the surface of the core material. The vacuum insulation panel 2 has a temperature resistance of -200℃ and a thermal conductivity of 4~4.5 mW / (m·K) at room temperature. The thickness of the vacuum insulation panel 2 is 30~40 mm, and the surface can be flat or have a certain curvature. It has a compressive strength of up to 137 MPa (the allowable stress of 304 stainless steel at low temperature is 137 MPa). The vacuum insulation panel 2 and the polyurethane board 3 are bonded together by low-temperature adhesive layers.

[0039] In the first space 5, there are 7 to 9 layers of insulation panels and 6 to 8 layers of the first polyurethane panel. This means that each vacuum insulation panel 2 is spaced apart to accommodate the prefabricated polyurethane panel 3. The rigid polyurethane in the first space 5 acts as a buffer for the vacuum insulation panels, and the thickness of a single rigid polyurethane panel is 50 to 70 mm. The rigid polyurethane in the second space 6 has a thickness of 80 to 100 mm and consists of 2 to 4 layers, preferably 3 layers.

[0040] In the second space 6, a gap of 10-40 mm is provided between each polyurethane board 3. Specifically, gaps are arranged along the thickness direction and circumferential direction of the polyurethane board 3. The gaps are used to install the elastic felt 7 to compensate for the shrinkage of the inner tank 4 of the spherical tank along the thickness direction and circumferential direction, and to play a certain role in heat insulation.

[0041] The insulation system of the liquid hydrogen spherical tank also includes polyurethane foam. In a preferred embodiment, the polyurethane foam is a rigid polyurethane foam that is foamed on-site. The polyurethane foam fills the installation gap between the vacuum insulation panel 2 and the outer tank 1 in the first space 5, and plays the role of bonding the vacuum insulation panel and the outer tank 1, filling the gap and providing insulation.

[0042] The elastic felt 7 is made of polyisocyanate (a foam material, also known as PIR) to ensure low thermal conductivity. During installation, it is pre-compressed to 40-60% of its thickness to compensate for deformation of the inner tank 4 after filling with liquid hydrogen and displacement of the insulation material.

[0043] like Figure 2 As shown, in the first space 5, the vacuum insulation panel 2 and the polyurethane panel 3 are staggered along the thickness direction. Preferably, the edge of a single polyurethane panel 3 is collinear with the central axis of a vacuum insulation panel 2 on the layer above it. The elastic felt 7 can be filled into the gaps between the panels of each layer of vacuum insulation panel 2 and between the panels of each layer of polyurethane panel 3.

[0044] In the second space 6, polyurethane boards 3 of different layers are staggered along the thickness direction. Preferably, the edge of a single polyurethane board 3 is collinear with the central axis of a polyurethane board 3 of the layer above it.

[0045] This invention allows for the installation of vacuum insulation panels 2 and polyurethane panels 3 with specific layers and thicknesses, tailored to the specific thickness of the insulation interlayer. It is crucial to ensure that the surface temperature of the vacuum insulation panel 2 in the first space 5 does not fall below -200°C to prevent damage due to low temperatures. Specifically, before installation in the spherical tank, theoretical calculations are used to determine the arrangement thickness of the vacuum insulation panel 2, the polyurethane panels 3 in the first space 5, and the total thickness of the polyurethane panels 3 in the second space 6, based on the total thickness of the interlayer. This ensures that the surface temperature of the vacuum insulation panel 2 does not fall below -200°C. In this invention, the 304 stainless steel material used in the vacuum insulation panel can withstand extremely low temperatures. Furthermore, the fumed silica core material used in the vacuum insulation panel is also unaffected by low temperatures. Therefore, theoretically, a vacuum insulation panel using 304 stainless steel as a barrier membrane can be used in a liquid hydrogen temperature environment. In the specific experiment, the upper and lower surfaces of the vacuum insulation panel were placed at -220 ℃ and 45 ℃ respectively for 48 hours. During the experiment, a large temperature gradient existed within the vacuum insulation panel, and the thermal conductivity at its center remained stable at 4~4.5 mW / (m·K). Furthermore, after the vacuum insulation panel was removed for a period of time, no problems such as puncture or rebound occurred. This indicates that the vacuum insulation panel 2 can operate normally in a low-temperature environment of -210℃ and was not damaged under extreme temperature gradients. Since lower temperature tests were not conducted, to ensure safety, the minimum operating temperature of the vacuum insulation panel in this invention was ultimately set at approximately -200℃. In summary, the above-described experiments were conducted on this invention. The tests show that under extreme operating conditions, the vacuum insulation panel still maintains good insulation performance (the thermal conductivity at the center remains stable at 4~4.5 mW / (m·K)). This demonstrates that the liquid hydrogen spherical tank provided by this invention, due to the use of the vacuum insulation panel 2, can still meet the usage requirements even without vacuuming before the tank is used.

[0046] This invention installs and fixes a vacuum insulation panel 2, a polyurethane panel 3, and an elastic felt 7 in the interlayer between the inner tank 4 and the outer tank 1 of the liquid hydrogen spherical tank, forming an insulated enclosure for the liquid hydrogen spherical tank. This invention can minimize heat leakage from the liquid hydrogen spherical tank without vacuuming, thereby meeting the daily evaporation rate requirements of the liquid hydrogen spherical tank.

[0047] This utility model relates to a thermal insulation system primarily for large cryogenic spherical tanks. Addressing the challenges of vacuuming existing large liquid hydrogen spherical tank insulation systems that rely on stacked insulation, and the time and cost associated with vacuuming, this utility model proposes a novel thermal insulation structure (i.e., a vacuum insulation panel 2 comprising a core material of fumed silica and a 304 stainless steel composite barrier film). This system achieves excellent thermal insulation with a relatively small insulation thickness and eliminates the need for vacuuming, providing a superior thermal insulation performance for liquid hydrogen spherical tanks.

[0048] This utility model also provides a liquid hydrogen spherical tank, which employs the insulation system of the liquid hydrogen spherical tank.

[0049] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "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 application 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 limitations on this application.

[0050] The specific embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the substantive content of this utility model. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. An insulation system for a liquid hydrogen spherical tank, characterized in that, It includes a heat insulation structure, which includes an inner tank (4), an outer tank (1), a vacuum heat insulation panel (2), a polyurethane panel (3), and an elastic felt (7). The outer tank (1) is fitted outside the inner tank (4), and the vacuum insulation board (2), polyurethane board (3) and elastic felt (7) are all located between the outer tank (1) and the inner tank (4); The insulation structure is divided into a first space (5) and a second space (6) along the thickness direction of the spherical tank; the outer tank (1) is located in the first space (5), and the inner tank (4) is located in the second space (6); The first space is also equipped with multiple layers of insulation boards, each layer of insulation boards including multiple vacuum insulation boards (2), and a first polyurethane board layer is arranged between different layers of insulation boards, the first polyurethane board layer including multiple polyurethane boards (3). The second space (6) is provided with multiple layers of second polyurethane boards, the second polyurethane boards including multiple polyurethane boards (3); In the second space (6), elastic felt (7) is filled between different polyurethane boards (3).

2. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, The vacuum insulation panel (2) includes A fumed silica core material is combined with a 304 stainless steel composite barrier film. The vacuum degree inside the fumed silica core material is less than 10 Pa, and the 304 stainless steel composite barrier film is coated on the surface of the core material.

3. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, In the first space (5), the number of insulation board layers is 7 to 9 and the number of first polyurethane board layers is 6 to 8; In the second space (6), a gap of 10 to 40 mm is provided between each polyurethane board (3), and the gap is used to install the elastic felt (7).

4. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, The thickness of the vacuum insulation board (2) is 30~40mm, and the vacuum insulation board (2) and the polyurethane board (3) are bonded together by a low-temperature adhesive layer.

5. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, The insulation system of the liquid hydrogen spherical tank also includes polyurethane foam, which is filled in the installation gap between the vacuum insulation panel (2) and the outer tank (1) in the first space (5).

6. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, The elastic felt (7) is made of polyisocyanate and is pre-compressed to a thickness of 40-60% during installation.

7. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, In the first space (5), the vacuum insulation board (2) and the polyurethane board (3) are staggered along the thickness direction, and the elastic felt (7) is filled in the gaps generated at the connection between the boards of each layer of vacuum insulation board (2) and the connection between the boards of the polyurethane board (3).

8. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, In the first space (5), the thickness of a single polyurethane board (3) is 50~70 mm; The second polyurethane board layer set in the second space (6) has 2 to 4 layers and a thickness of 80 to 100 mm.

9. The insulation system of the liquid hydrogen spherical tank according to claim 1, characterized in that, The thickness of the 304 stainless steel barrier film is 0.15~0.20 mm.

10. A liquid hydrogen spherical tank, characterized in that, The insulation system of the liquid hydrogen spherical tank according to any one of claims 1 to 9.

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