LNG full containment tank

Abstract

This utility model relates to the field of pressure vessel technology and discloses an LNG full-containment tank, including a tank body and an insulation layer. The tank body includes an inner tank and an outer tank, with the inner tank disposed inside the outer tank. A gap exists between the inner and outer tanks to form a top cavity, a side cavity, and a bottom cavity. The insulation layer includes a top insulation layer, a side insulation layer, and a bottom insulation layer. The top insulation layer is located in the top cavity, the bottom insulation layer is located in the bottom cavity, and the side insulation layers are located in the side cavities. The side insulation layer includes an inner elastic felt and an outer elastic felt. The inner elastic felt is disposed on the inner tank and covers the outer side wall of the inner tank, while the outer elastic felt is disposed on the outer tank and covers the inner side wall of the outer tank. The outer elastic felt is spaced apart from the inner elastic felt when under vacuum compression, and abuts against the inner elastic felt when not under vacuum compression. Expanded perlite is filled on top of the side insulation layer. This LNG full-containment tank can ensure the heat insulation and cold preservation performance of the storage tank during operation and extend its service life.

Description

Technical Field

[0001] This utility model relates to the field of pressure vessel technology, and in particular to an LNG full-containment tank. Background Technology

[0002] LNG full-containment tanks are advanced storage systems specifically designed for liquefied natural gas (LNG). Existing LNG full-containment tanks consist of an inner tank and an outer tank. The inner tank stores cryogenic media (such as LNG), and the space between the inner and outer tanks is filled with elastic material and expanded perlite. Expanded perlite provides insulation to form a continuous cold insulation layer to maintain the cryogenic temperature of the inner tank. The elastic material replenishes the radial position created by the inner tank's contraction and expansion throughout the tank's operation, supporting the expanded perlite level and preventing a drop in the perlite level due to inner tank contraction, which could lead to incomplete insulation and cold leakage. To prevent a drop in the expanded perlite level during continuous operation, secondary filling with expanded perlite is required when the inner tank contracts. However, this filling process also introduces a large amount of air between the inner and outer tanks. The moisture in this air condenses between the two tanks, forming condensate that can cause equipment corrosion and thus affect the tank's service life.

[0003] Therefore, there is an urgent need for a full-containment LNG tank to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to provide an LNG full-containment tank to solve the problem of the expansion perlite level dropping during tank operation, ensure the heat insulation and cold preservation performance of the tank, and extend the service life of the tank.

[0005] Based on the above concept, the technical solution adopted by this utility model is as follows:

[0006] Provides an LNG full-containment tank, comprising:

[0007] The tank includes an inner tank and an outer tank, the inner tank being disposed inside the outer tank, and a gap being provided between the inner tank and the outer tank to form a top cavity, a side cavity, and a bottom cavity, the side cavity being used to contain expanded perlite;

[0008] The insulation layer includes a top insulation layer, a side insulation layer and a bottom insulation layer, wherein the top insulation layer is located in the top cavity, the bottom insulation layer is located in the bottom cavity, and the side insulation layer is located in the side cavity;

[0009] The side insulation layer includes an inner elastic felt and an outer elastic felt. The inner elastic felt is disposed on the inner tank and covers the outer side wall of the inner tank, and the outer elastic felt is disposed on the outer tank and covers the inner side wall of the outer tank. When the outer elastic felt is under vacuum compression, it is spaced apart from the inner elastic felt. When the outer elastic felt is not under vacuum compression, it abuts against the inner elastic felt. The expanded perlite is located above the side insulation layer.

[0010] Optionally, a first lifting device is provided on the side wall of the outer tank, the first lifting device being used to suspend the outer elastic felt.

[0011] Optionally, the first lifting device includes insulation nails, which are embedded in the side wall of the outer tank, and the outer elastic felt is suspended on the insulation nails.

[0012] Optionally, a second lifting device is provided on the side wall of the inner tank, the second lifting device being used to suspend the inner elastic felt.

[0013] Optionally, the second lifting device includes a fixed member and a hook connected together, the fixed member being fixed to the end of the inner elastic felt, and the hook being able to hang on the side wall of the inner tank.

[0014] Optionally, the side insulation layer further includes an inner glass cloth, which wraps the inner elastic felt;

[0015] The side insulation layer also includes an outer glass cloth, which wraps the outer elastic felt.

[0016] Optionally, the inner elastic felt is composed of multiple layers of elastic felt;

[0017] The external elastic felt is composed of multiple layers of elastic felt.

[0018] Optionally, the resilience coefficient of the elastic felt is greater than or equal to 44%;

[0019] The density range of the elastic felt is 15.0 kg / m³. 3 Up to 18kg / m 3 ;

[0020] The moisture content (by mass) of the elastic felt is less than or equal to 0.5%;

[0021] The tensile strength of the elastic felt is greater than or equal to 15 kPa;

[0022] The elastic felt has a fire rating of A1 (non-combustible).

[0023] The thermal conductivity of the elastic felt at 0°C is less than or equal to 0.04 W / (m·K).

[0024] Optionally, the bottom insulation layer is made of foam glass;

[0025] The top insulation layer is made of glass wool.

[0026] Optionally, the LNG full-containment tank further includes a vacuum bag, in which the outer elastic felt can be placed, and the vacuum bag is used to compress the outer elastic felt under vacuum.

[0027] The beneficial effects of this utility model are as follows:

[0028] This utility model proposes an LNG full-containment tank, comprising a tank body and an insulation layer. The tank body includes an inner tank and an outer tank, with the inner tank disposed inside the outer tank. A gap exists between the inner and outer tanks to form a top cavity, a side cavity, and a bottom cavity. The insulation layer includes a top insulation layer, a side insulation layer, and a bottom insulation layer. The top insulation layer is located in the top cavity, the bottom insulation layer is located in the bottom cavity, and the side insulation layers are located in the side cavities. The side insulation layer includes an inner elastic felt and an outer elastic felt. The inner elastic felt is disposed on the inner tank and covers its outer side wall, while the outer elastic felt is disposed on the outer tank and covers its inner side wall. The outer elastic felt is spaced apart from the inner elastic felt under vacuum compression. After the outer elastic felt is installed, the vacuum compression on the outer elastic felt can be released, and the outer elastic felt not under vacuum compression abuts against the inner elastic felt. The side cavity also houses expanded perlite, which fills the top of the side insulation layer. Expanded perlite has low thermal conductivity and is inexpensive. It is used between the inner and outer tanks to achieve insulation and cold preservation for the LNG full-containment tank. Therefore, the level of expanded perlite needs to meet certain requirements to avoid cold leakage. However, with the use of the LNG full-containment tank, the inner tank shrinks and the expanded perlite is compressed, both of which cause the side cavity to enlarge and the expanded perlite level to drop. At this time, both the inner and outer elastic felts can expand to support the expanded perlite level. In addition, the side insulation layer is divided into inner and outer elastic felts. Due to the low thermal conductivity of the elastic felt, the outer elastic felt further prevents low temperature transfer to the outer tank. The continuous, non-settling structure of the elastic felt effectively prevents condensation on the outer tank wall, reducing the risk of "black neck" (cold neck) that may occur after several years of operation. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view of the LNG full-containment tank provided in this embodiment of the utility model;

[0030] Figure 2 This is a schematic diagram of the installation of the side insulation layer provided in this embodiment of the utility model (the outer elastic felt is not compressed);

[0031] Figure 3 This is a schematic diagram of the installation of the side insulation layer (external elastic felt compression) provided in an embodiment of this utility model.

[0032] In the picture:

[0033] 1. Outer tank; 11. Dome; 2. Inner tank; 21. Ceiling; 3. Top insulation layer; 4. Side insulation layer; 41. Outer elastic felt; 42. Inner elastic felt; 43. First lifting device; 44. Second lifting device; 441. Hook; 442. Fixture; 5. Bottom insulation layer. Detailed Implementation

[0034] To make the technical problem solved by this utility model, the technical solution adopted, and the technical effect achieved clearer, the technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the accompanying drawings, not all of them.

[0035] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0036] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0037] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0038] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0039] like Figures 1 to 3 As shown, this embodiment provides an LNG full-containment tank, including a tank body and an insulation layer. The tank body includes an inner tank 2 and an outer tank 1, with the inner tank 2 disposed inside the outer tank 1. A gap exists between the inner tank 2 and the outer tank 1, including a top cavity, a side cavity, and a bottom cavity. The insulation layer includes a top insulation layer 3, a side insulation layer 4, and a bottom insulation layer 5. The top insulation layer 3 is located in the top cavity, the bottom insulation layer 5 is located in the bottom cavity, and the side insulation layer 4 is located in the side cavity. The side cavity is also used to accommodate expanded perlite, which fills the top of the side insulation layer 4. Expanded perlite has a low thermal conductivity and is inexpensive. Filling it between the inner tank 2 and the outer tank 1 achieves insulation and cold preservation for the LNG full-containment tank. Therefore, the level of expanded perlite filling needs to meet certain requirements to avoid cold leakage. However, with the use of LNG full-containment tanks, the shrinkage of the inner tank 2 and the compression between the expanded perlite will cause the level of expanded perlite to drop. To solve this problem, in this embodiment, the side insulation layer 4 is divided into two parts, namely, an inner elastic felt 42 and an outer elastic felt 41. The inner elastic felt 42 is set on the inner tank 2 and covers the outer side wall of the inner tank 2, while the outer elastic felt 41 is set on the outer tank 1 and covers the inner side wall of the outer tank 1.

[0040] In practice, the inner elastic felt 42 is first placed on the outer wall of the inner tank 2 in its natural state, and then the outer elastic felt 41 is placed on the inner wall of the outer tank 1 under vacuum compression. The outer elastic felt 41 under vacuum compression is spaced apart from the inner elastic felt 42. After the outer elastic felt 41 is installed, the vacuum compression is released, and the outer elastic felt 41, no longer under vacuum compression, comes into contact with the inner elastic felt 42. Then, expanded perlite can be filled into the side cavity. When the inner tank 2 contracts to enlarge the side cavity between the inner tank 2 and the outer tank 1, both the inner elastic felt 42 and the outer elastic felt 41 expand to support the level of the expanded perlite. When the side cavity between the inner tank 2 and the outer tank 1 shrinks, the inner elastic felt 42 and the outer elastic felt 41 can be compressed. In addition, the side insulation layer 4 is divided into two parts: inner elastic felt 42 and outer elastic felt 41. Because the thermal conductivity of the elastic felt is small, the setting of the outer elastic felt 41 can further prevent low temperature from being transferred to the outer tank 1. The continuous and non-settling elastic felt structure can effectively prevent condensation on the tank wall of the outer tank 1, thereby reducing the black neck situation that may occur in the LNG full-containment tank after a few years of operation.

[0041] Optionally, both the outer elastic felt 41 and the inner elastic felt 42 are formed by stacking multiple layers of elastic felt. In specific implementations, the thickness of each layer of elastic felt is approximately 100 mm, and both the outer elastic felt 41 and the inner elastic felt 42 generally have 2 to 3 stacked layers of elastic felt.

[0042] In this embodiment, the selection criteria for the elastic felt are as follows: 1. The resilience coefficient of the elastic felt is greater than or equal to 44%. 2. The density of the elastic felt is in the range of 15.0 kg / m³. 3 Up to 18kg / m 3 3. The moisture content (by mass) of the elastic felt is less than or equal to 0.5%. 4. The tensile strength of the elastic felt is greater than or equal to 15 kPa. 5. The elastic felt has a fire rating of A1 (non-combustible). 6. The thermal conductivity of the elastic felt at 0℃ is less than or equal to 0.04 W / (m·K).

[0043] Optionally, the side insulation layer 4 also includes an inner fiberglass cloth that wraps around an inner elastic felt 42. The side insulation layer 4 also includes an outer fiberglass cloth that wraps around an outer elastic felt 41. Wrapping the inner elastic felt 42 with the inner fiberglass cloth prevents expanded perlite from entering the inner elastic felt 42. Simultaneously, the inner fiberglass cloth increases the tensile strength of the inner elastic felt 42, facilitating its suspension on the outer wall of the inner tank 2. Wrapping the outer elastic felt 41 with the outer fiberglass cloth has the same effect.

[0044] Optionally, such as Figure 3 As shown, a first lifting device 43 is provided on the side wall of the outer tank 1, which is used to suspend the outer elastic felt 41. In the height direction of the outer tank 1, one end of the outer elastic felt 41 extends to the top of the side wall of the outer tank 1, and the other end extends to the bottom of the side wall of the outer tank 1, so that the outer elastic felt 41 can completely cover the inner side wall of the outer tank 1. The first lifting device 43 can be a heat-insulating nail provided on the side wall of the outer tank 1, and a through hole can be provided on one end of the outer elastic felt 41 so that the heat-insulating nail can pass through the outer elastic felt 41 to fix the outer elastic felt 41.

[0045] In this embodiment, the insulation nails are pre-embedded on the side wall of the outer tank 1. The outer tank 1 is generally made of concrete, so the insulation nails can be pre-embedded on one side of the inner side wall of the outer tank 1 during construction, and the outer elastic felt 41 can then be directly suspended on the insulation nails.

[0046] Optionally, such as Figure 3 As shown, a second lifting device 44 is provided on the side wall of the inner tank 2 for suspending the inner elastic felt 42. In the height direction of the inner tank 2, one end of the inner elastic felt 42 extends to the top of the side wall of the inner tank 2, and the other end extends to the bottom of the side wall of the inner tank 2, so that the inner elastic felt 42 can completely cover the outer side wall of the inner tank 2. The second lifting device 44 can be fixedly connected to the side wall of the inner tank 2, or it can be connected in other detachable ways.

[0047] In this embodiment, the second lifting device 44 includes a fixed member 442 and a hook 441 connected together. The fixed member 442 is fixed to the end of the inner elastic felt 42, and the hook 441 can be hung on the side wall of the inner tank 2. The inner tank 2 is generally made of metal, and the hook 441 can be hung on the edge of the side wall.

[0048] In practice, the inner tank 2 is located on the inner wall of the outer tank 1. The upper opening of the inner tank 2 is sealed by the ceiling 21, and the upper opening of the outer tank 1 is sealed by the dome 11. First, a bottom insulation layer 5 is laid, which is made of foam glass. Then, a side insulation layer 4 is laid, which is made of elastic felt. Finally, a top insulation layer 3 is laid above the ceiling 21, which is made of glass wool.

[0049] In practice, the LNG full-containment tank also includes a vacuum bag, inside which the outer elastic felt 41 can be placed. The vacuum bag is used to compress the outer elastic felt 41 under vacuum. Even after being suspended, the vacuum-compressed outer elastic felt 41 still maintains a gap from the inner elastic felt 42, facilitating the suspension of the outer elastic felt 41. Once the outer elastic felt 41 is in place, the vacuum bag can be removed, allowing the outer elastic felt 41 to naturally expand and come into contact with the inner elastic felt 42, thereby filling the side cavity.

[0050] In this embodiment, the inner elastic felt 42 is installed in its normal, natural state, while the outer elastic felt 41 is installed under compression. After installation, the outer elastic felt 41 is released, and the inner and outer elastic felts 42 and 41 fill the entire annular cavity. Expanded perlite, after filling, is positioned above the elastic felt. The elastic felt expands when the inner tank 2 contracts, ensuring that the level of the expanded perlite does not sink. Furthermore, both the inner and outer elastic felts 42 and 41 are suspended, preventing breakage and settling, thus ensuring structural continuity and preventing condensation on the outer tank 1.

[0051] The above embodiments merely illustrate the basic principles and characteristics of this utility model. This utility model is not limited to the above embodiments. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. An LNG full-containment tank, characterized in that, include: The tank body includes an inner tank (2) and an outer tank (1), the inner tank (2) being disposed inside the outer tank (1), and a gap being provided between the inner tank (2) and the outer tank (1) to form a top cavity, a side cavity and a bottom cavity, the side cavity being used to contain expanded perlite; The insulation layer includes a top insulation layer (3), a side insulation layer (4) and a bottom insulation layer (5), wherein the top insulation layer (3) is located in the top cavity, the bottom insulation layer (5) is located in the bottom cavity, and the side insulation layer (4) is located in the side cavity. The side insulation layer (4) includes an inner elastic felt (42) and an outer elastic felt (41). The inner elastic felt (42) is disposed on the inner tank (2) and covers the outer side wall of the inner tank (2). The outer elastic felt (41) is disposed on the outer tank (1) and covers the inner side wall of the outer tank (1). When the outer elastic felt (41) is in a vacuum compression state, it is spaced apart from the inner elastic felt (42). When the outer elastic felt (41) is not in a vacuum compression state, it abuts against the inner elastic felt (42). The expanded perlite is located above the side insulation layer (4).

2. The LNG full-containment tank according to claim 1, characterized in that, The outer tank (1) is provided with a first lifting device (43) on its side wall, which is used to suspend the outer elastic felt (41).

3. The LNG full containment tank according to claim 2, characterized in that, The first lifting device (43) includes insulation nails, which are embedded in the side wall of the outer tank (1), and the outer elastic felt (41) is suspended on the insulation nails.

4. The LNG full containment tank of claim 1, wherein A second lifting device (44) is provided on the side wall of the inner tank (2), which is used to suspend the inner elastic felt (42).

5. The LNG full-containment tank according to claim 4, characterized in that, The second lifting device (44) includes a fixed member (442) and a hook (441) connected together. The fixed member (442) is fixed to the end of the inner elastic felt (42), and the hook (441) can be hung on the side wall of the inner tank (2).

6. The LNG full-containment tank according to claim 1, characterized in that, The side insulation layer (4) also includes an inner glass cloth, which wraps the inner elastic felt (42). The side insulation layer (4) also includes an outer glass cloth, which wraps the outer elastic felt (41).

7. The LNG full-containment tank according to claim 1, characterized in that, The internal elastic felt (42) is composed of multiple layers of elastic felt; The external elastic felt (41) is composed of multiple layers of elastic felt.

8. The LNG full-containment tank according to claim 7, characterized in that, The resilience coefficient of the elastic felt is greater than or equal to 44%; The density range of the elastic felt is 15.0 kg / m³. 3 Up to 18kg / m 3 ; The moisture content of the elastic felt is less than or equal to 0.5% by mass; The tensile strength of the elastic felt is greater than or equal to 15 kPa; The elastic felt has a fire rating of A1 (non-combustible). The thermal conductivity of the elastic felt at 0°C is less than or equal to 0.04 W / (m·K).

9. The LNG full-containment tank according to claim 1, characterized in that, The bottom insulation layer (5) is made of foam glass; The top insulation layer (3) is made of glass wool.

10. The LNG full-containment tank according to claim 1, characterized in that, The LNG full-containment tank also includes a vacuum bag, in which the outer elastic felt (41) can be placed, and the vacuum bag is used to put the outer elastic felt (41) into a vacuum compression state.

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