KR20250019173A - Type-c liqufied hydrogen cargo tanks with integrated support structure and manufacturing method for support structure - Google Patents

Abstract

The present invention relates to a Type-C liquefied hydrogen storage tank and a method for manufacturing a support structure, the support structure including a tank body including a capsule-shaped inner tank for storing ultra-low temperature liquefied hydrogen and an outer tank configured to surround the inner tank and spaced apart from the inner tank by a certain distance; a vacuum space formed between the inner tank and the outer tank; a plurality of support structures connecting the inner tank and the outer tank; and a tank dome connected to an upper portion of one side of the tank body, which can provide lower manufacturing cost and superior insulation performance than conventional glass fiber reinforced plastic (GFRP).

Description

{TYPE-C LIQUFIED HYDROGEN CARGO TANKS WITH INTEGRATED SUPPORT STRUCTURE AND MANUFACTURING METHOD FOR SUPPORT STRUCTURE}

The disclosed invention relates to a Type-C liquefied hydrogen storage tank with an integrated support structure and a method for manufacturing the support structure.

According to the International Maritime Organization (IMO) classification, hydrogen standalone liquefied gas storage tanks are divided into Type-A, Type-B, and Type-C tanks. These tank types are designed to transport different types of liquefied gases under different pressure and temperature conditions.

IMO Type-A and Type-B tanks are designed with a design pressure of 0.7 bar or less. Type-A is designed according to a conventional design, and is suitable for transporting liquefied gas at temperatures below -55 degrees Celsius because the hull acts as a secondary barrier in case of a leak from the primary barrier. Type-B is designed through detailed analysis, and the drip tray acts as a secondary barrier in case of a leak from the primary barrier. Type-B tanks are made of cryogenic steels such as aluminum, 9% nickel steel, and high manganese steel.

In contrast, IMO Type-C tanks are self-contained pressure vessels designed to carry liquefied gases at higher pressures.

The main purpose of the liquefied gas storage tank is to maintain the temperature of the liquefied gas below the boiling point during transportation and storage. When the tank capacity is small and medium (approximately 3,000 to 10,000 m3), the Type-C tank is known to be suitable. The utilization of liquefied hydrogen as an energy source to prepare for global warming and achieve carbon neutrality is increasing, and Type-C liquefied hydrogen storage tanks are being used to transport it.

Since liquefied hydrogen (-253°C) is an ultra-low temperature compared to LNG (-163°C), it is difficult to apply the existing insulation system, polyurethane foam, in reality due to excessive insulation thickness. Therefore, a double vacuum Type-C tank, which supports the inner tank that stores liquefied hydrogen, the outer tank arranged separately from the inner tank, and the space between the inner/outer tanks (annular space) with a low thermal conductivity composite material such as GFRP, and in which the annular space is filled with insulation material and a vacuum is created to secure insulation performance, was applied to the actual ship. However, such an insulation system can cause problems in terms of installation, maintenance, weight, and overall performance.

In addition, the manufacturing methods used in the prior art to produce the insulation structures and integrate them with independent Type-C tanks are relatively complex and time-consuming. The assembly of these insulation systems typically involves the installation of multiple layers of insulation, each requiring specific handling and installation procedures. This not only increases labor and production costs, but can also increase the risk of installation errors or inconsistent insulation performance.

Republic of Korea Patent Publication No. 10-2012-0004652 (Published on January 13, 2012)

For the above reasons, one aspect of the disclosed invention is to provide a Type-C liquid hydrogen storage tank and a method for manufacturing the support structure, which integrate a support structure by applying a wooden block sealed with sheet metal as the support structure, so as to realize better insulation properties and lower manufacturing costs than before.

According to one aspect of the disclosed invention, a Type-C liquid hydrogen storage tank with an integrated support structure may include a tank body including an inner tank in a capsule shape for storing ultra-low temperature liquid hydrogen and an outer tank configured to surround the inner tank and be spaced apart from the inner tank by a predetermined distance; a vacuum space formed between the inner tank and the outer tank; a plurality of support structures connecting the inner tank and the outer tank; and a tank dome connected to an upper portion of one side of the tank body.

One side of the above tank body can be divided into a fixed part and the other side into a sliding part.

The above-described fixed member may further include a pillar holder that supports the plurality of support structures so that they are fixed to the outside of the inner tank and the inside of the outer tank.

The above sliding member may further include a pillar holder that supports the plurality of support structures so that they are fixed to the outside of the inner tank or the inside of the outer tank.

The above plurality of support structures may include: wooden blocks; and sheet metal sealing the wooden blocks.

One side of the above wooden block can be subjected to a chamfering operation.

The above sheet metal may be a sheet metal for cryogenic use.

The above sheet metal can be either SUS304 or SUS316.

The thickness of the four sides of the above sheet metal can be 1 mm to 2 mm.

The thickness of the upper and lower surfaces of the above sheet metal may be 3 mm to 4 mm.

According to one aspect of the disclosed invention, a method for manufacturing a support structure for a Type-C liquid hydrogen storage tank may include the steps of: manufacturing a sheet metal; manufacturing a wooden block; performing a chamfering operation on one surface of the wooden block; inserting the wooden block into the sheet metal; and welding an upper surface of the sheet metal.

The step of manufacturing the above sheet metal can be performed by welding the four side surfaces and the lower surface excluding the upper surface of the sheet metal to manufacture it in a form in which the upper surface is open.

The step of inserting the wooden block into the sheet metal may be performed such that the surface of the wooden block on which the chamfering operation was performed faces the upper surface of the sheet metal.

According to one aspect of the disclosed invention, a Type-C liquid hydrogen storage tank and a method for manufacturing the support structure integrated with a support structure capable of realizing lower manufacturing cost and superior insulation performance than conventional glass fiber reinforced plastic (GFRP) can be provided.

Accordingly, the Type-C liquid hydrogen storage tank with integrated support structure can provide safety and economy compared to the existing Type-C liquid hydrogen storage tank.

Figure 1 illustrates the configuration of a Type-C liquefied hydrogen storage tank with an integrated support structure according to one embodiment.
FIG. 2 illustrates a cross-sectional view of a Type-C liquefied hydrogen storage tank with an integrated support structure according to one embodiment.
FIG. 3 illustrates a support structure provided on each of a fixed portion and a sliding portion of a Type-C liquid hydrogen storage tank integrated with a support structure according to one embodiment.
Figure 4 is a diagram schematically illustrating a manufacturing process of a support structure according to one embodiment.
Figure 5 is a flowchart showing a method for manufacturing a support structure according to one embodiment.
FIG. 6 is a diagram comparing the characteristics and insulation effects of a support structure according to one embodiment and a conventional glass fiber reinforced plastic (GFRP)-based support structure.

Like reference numerals refer to like elements throughout the specification. This specification does not describe all elements of the embodiments, and any content that is general in the technical field to which the disclosed invention belongs or that overlaps between the embodiments is omitted. The terms 'part, module, element, block' used in the specification can be implemented in software or hardware, and according to the embodiments, a plurality of 'parts, modules, elements, blocks' can be implemented as a single element, or a single 'part, module, element, block' can include a plurality of elements.

Throughout the specification, when a part is said to be 'connected' to another part, this includes not only direct connection but also indirect connection, and indirect connection includes connection via a wireless communications network.

Additionally, when a part is said to 'include' a component, this does not mean that it excludes other components, unless otherwise specifically stated, but rather that it may include other components.

Throughout the specification, when we say that an element is located 'on' another element, this includes not only cases where an element is in contact with another element, but also cases where another element exists between the two elements.

The terms first, second, etc. are used to distinguish one component from another, and the components are not limited by the aforementioned terms.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

The identification codes in each step are used for convenience of explanation and do not describe the order of each step. Each step may be performed in a different order than specified unless the context clearly indicates a specific order.

The working principle and embodiments of the disclosed invention will be described with reference to the attached drawings below.

In the following description, the term referring to the 'Type-C liquid hydrogen storage tank (100)' of the present invention may be abbreviated as 'C-type tank (100)' for convenience of explanation.

FIG. 1 illustrates a configuration of a Type-C liquid hydrogen storage tank (100) with an integrated support structure (50) according to one embodiment, and FIG. 2 illustrates a cross-sectional view of a Type-C liquid hydrogen storage tank (100) with an integrated support structure (50) according to one embodiment.

Referring to FIGS. 1 and 2, the C-type tank (100) includes a tank body (10) including an inner tank (20) in a capsule shape for storing ultra-low temperature liquefied hydrogen, an outer tank (30) configured to surround the inner tank (20) while being spaced apart from the inner tank (20) by a certain distance, a vacuum space (40) formed between the inner tank (20) and the outer tank (30), a plurality of support structures (50) connecting the inner tank (20) and the outer tank (30), a pillar holder (70) that supports the plurality of support structures (50) so as to be fixed to the outer side (inner tank) of the inner tank (20) and the inner side (outer tank) of the outer tank (30), and a tank dome (60) connected to the upper side of one side of the tank body (10), and one side of the inner tank (20) and the outer tank (30) is a fixed part and the other side is a sliding part. It is divided into sections.

The tank body (10) is configured to include an inner tank (20) and an outer tank (30).

The inner tank (20) can store cryogenic liquid hydrogen.

The outer tank (30) is spaced apart from the inner tank (20) at a certain distance to form a vacuum space (40).

The inner tank (20) and the outer tank (30) may be provided in a capsule shape.

The inner tank (20) may be made of cryogenic steel for storing cryogenic liquid hydrogen.

The outer tank (30) may be made of carbon steel.

The tank body (10) may include a fixed part and a sliding part.

In a C-type tank (100), the tank dome (60) can provide various utilities such as stress distribution, volume optimization, vaporization space management, and installation of piping and instrumentation equipment.

The inner tank (20) and the outer tank (30) are spaced apart from each other by a certain distance to form a vacuum space (40). This vacuum space (40) is a space where a support structure (50) is placed. That is, the width of the vacuum space (40) is the same as the height of the support structure (50).

The support structure (50) is arranged so as to be in contact with the inner tank (20) and the outer tank (30).

The support structure (50) can be installed on the fixed part and the sliding part, and a plurality of support structures (50) can be installed spaced apart from each other at a certain distance along a circular shape.

The support structure (50) installed on the fixed part can be stably fixed to the inner tank (20) and the outer tank (30) by the pillar holder (70). At this time, the pillar holder (70) can be installed on both sides of the support structure (50) that contacts the outer side (inner tank) of the inner tank (20) and the inner side (outer tank) of the outer tank (30) to serve as a support.

The support structure (50) installed on the sliding part can be stably fixed to the inner tank (20) or the outer tank (30) by the pillar holder (70). At this time, the pillar holder (70) can be installed on either the outer side (inner tank) of the inner tank (20) or the inner side (outer tank) of the outer tank (30) to serve as a support for the support structure (50). By positioning the pillar holder (70) only in one direction of the support structure (50) installed on the sliding part in this way, a certain degree of longitudinal movement can be permitted.

A pair of pillar holders (70) may be installed on the outside (inner tank) of the inner tank (20) and/or on the inside (outer tank) of the outer tank (30) for each support structure (50). A pair of pillar holders (70) installed on the inner tank may be made of cryogenic steel. A pair of pillar holders (70) installed on the outer tank may be made of carbon steel.

The inner tank (20) and the outer tank (30) are circular in cross-section, as shown in Fig. 2.

The width of the vacuum space (40) is the distance between the inner tank (20) and the outer tank (30), and is equal to the height of the support structure (50).

A tank dome (60) is connected to the upper part of one side of the tank body (10). The tank dome (60) performs various roles in the C-type tank (100).

FIG. 3 illustrates a support structure (50) provided on each of the fixed and sliding parts of a Type-C liquid hydrogen storage tank (100) in which a support structure (50) is integrated according to one embodiment.

As shown in Fig. 3, the support structure (50) installed in the fixed portion can be stably fixed to the inner tank (20) and the outer tank (30) by the pillar holder (70). At this time, the pillar holder (70) can be installed to act as a support on both sides of the support structure (50) that contacts the outer side (inner tank) of the inner tank (20) and the inner side (outer tank) of the outer tank (30).

The support structure (50) installed on the sliding part can be stably fixed to the inner tank (20) or the outer tank (30) by the pillar holder (70). At this time, the pillar holder (70) can be installed on either the outer side (inner tank) of the inner tank (20) or the inner side (outer tank) of the outer tank (30) to serve as a support for the support structure (50). By positioning the pillar holder (70) only in one direction of the support structure (50) installed on the sliding part in this way, a certain degree of longitudinal movement can be permitted.

A pair of pillar holders (70) may be installed on the outside (inner tank) of the inner tank (20) and/or on the inside (outer tank) of the outer tank (30) for each support structure (50). A pair of pillar holders (70) installed on the inner tank may be made of cryogenic steel. A pair of pillar holders (70) installed on the outer tank may be made of carbon steel.

The support structure (50) may be composed of a wooden block (51) and a sheet metal (52) sealing the wooden block (51). The wooden block (51) has excellent low-temperature strength and low thermal conductivity. Therefore, it is suitable as a support structure for a C-type tank (100). However, the wooden block (51) is deformed due to an out-gassing phenomenon in which moisture inside escapes into the vacuum space when in a vacuum state, and it also causes difficulty in maintaining the vacuum in the vacuum space.

To solve this problem, the support structure (50) can be configured to further include a sheet metal (52) that seals the wooden block (51). By sealing the wooden block (51) with the sheet metal (52), the out-gassing phenomenon can be prevented. The sheet metal (52) can secure sufficient airtightness through welding. In addition, the sheet metal (52) requires a considerably smaller area than the wooden block (51), so that the actual heat transfer amount is not a major problem despite the high thermal conductivity. This will be described in more detail later in the description of FIG. 6.

The sheet metal (52) may be a sheet metal (52) for cryogenic use. For example, it may be SUS304 or SUS 316.

Preferably, the support structure (50) may have a rectangular or square shape in two dimensions, and a rectangular or cuboid shape in three dimensions. This facilitates the production process of the wood block (51) and the sheet metal (52) sealing the wood block (51), reduces costs, and ensures high reliability.

Meanwhile, the thickness of the four sides of the sheet metal (52) may be 1 mm to 2 mm. In addition, the thickness of the upper and lower surfaces of the sheet metal (52) may be 3 mm to 4 mm. However, this is not limited thereto, and the thickness may be determined differently depending on design requirements.

The width, length, and height of the sheet metal (52) can be determined by considering the difference in thermal expansion coefficients between the sheet metal (52) and the wooden block (51) to a size that forms a certain gap with the wooden block (51). Since the temperature of the installation environment is considerably lower, about -120 degrees Celsius on average, compared to the manufacturing environment, the sheet metal (52) and the wooden block (51) experience shrinkage when installed in the C-type tank (100). Therefore, a slight gap between the sheet metal (52) and the wooden block (51) can be allowed in the manufacturing environment. Accordingly, even if there is a gap between the sheet metal (52) and the wooden block (51) in the manufacturing environment, the sheet metal (52) shrinks more than the wooden block (51) in the installation environment, thereby tightly wrapping the wooden block (51), thereby preventing unnecessary relative movement or slipping. Therefore, considering the difference in thermal expansion coefficients of the sheet metal (52) and the wooden block (51), the size of the sheet metal (52) can be designed to be slightly larger so that a certain gap can be formed. The thermal expansion coefficient of the sheet metal (52) is And the coefficient of thermal expansion of the wooden block (51) is am.

Figure 4 is a diagram schematically illustrating a manufacturing process of a support structure (50) according to one embodiment.

First, a sheet metal (52) is manufactured. The sheet metal (52) is manufactured in the shape of a rectangular solid or a hexahedron, and is manufactured to a size that can accommodate a wooden block (51) but can be sealed. At this time, one side is excluded from the manufacturing. This is to accommodate a wooden block (51).

Next, a wooden block (51) is processed. At this time, the wooden block (51) can be designed to a size that takes into account the width of the vacuum space (40) and the thickness of the sheet metal (52).

Next, one side of the wooden block (51) is subjected to a chamfering operation. This is to prevent ignition of the wooden block (51) when welding is performed for sealing after the wooden block (51) is placed inside the sheet metal (52).

Then, the side on which the motley work was performed is placed on the sheet metal (52) so that it faces the open side.

Finally, the last surface of the sheet metal (52) is welded to complete the support structure (50).

Figure 5 is a flow chart showing a method for manufacturing a support structure (50) according to one embodiment.

Referring to FIG. 5, the method for manufacturing a support structure (50) may include a step of manufacturing a sheet metal (52) (S110), a step of manufacturing a wooden block (51) (S120), a step of performing a chamfering operation on one side of the wooden block (51) (S130), a step of inserting the wooden block (51) into the sheet metal (52) (S140), and a step of welding the upper surface (S150).

In the step (S110) of manufacturing the sheet metal (52), the thickness of the four sides of the sheet metal (52) may be from 1 mm to 2 mm. In addition, the thickness of the upper and lower surfaces of the sheet metal (52) may be from 3 mm to 4 mm. In addition, the step (S110) of manufacturing the sheet metal (52) may be manufactured in a form in which the upper part is open by welding the four sides and the lower surface of the sheet metal (52) except for the upper surface.

The step (S130) of performing a mortising operation on one side of a wooden block (51) can be performed to prevent ignition of the wooden block (51) when performing a welding operation for sealing after the wooden block (51) is placed inside a sheet metal (52).

FIG. 6 is a diagram comparing the characteristics and insulation effect of a support structure (50) according to one embodiment and a conventional glass fiber reinforced plastic (GFRP)-based support structure.

Referring to FIG. 6, the parameters of the support structure (50) including a wooden block (51) and a sheet metal (52) and the glass fiber reinforced plastic (GFRP), such as the heat transfer area A, the thermal conductivity K, the gap between the inside and outside of the hydrogen tank, the temperature difference between the inside and outside of the hydrogen tank, and the heat transfer amount can be compared.

In the case of heat transfer area A, it can be seen that the wood block (51) and GFRP have the same area (A), and the heat transfer area of the thin plate metal (52) (thin plate SUS) is approximately 0.015A to 0.018A.

For thermal conductivity K, the wood block (51) is 0.227, the sheet metal (52) is 8.6, and the GFRP is 0.4.

The gap and temperature difference between the inner and outer tanks of the hydrogen tank are all the same.

Looking at the heat transfer amount Q, the wood block (51) is 0.227A, the thin plate metal (52) is 0.129A to 0.155A, and GFRP is 0.4A.

In a comprehensive view, the total heat transfer Q of the support structure (50) including the wood block (51) and the sheet metal (52) is 0.356A to 0.382A, which is about 5% to 11% more excellent in insulation effect than 0.4A of GFRP. That is, the support structure (50) according to one embodiment of the present invention can provide better insulation performance along with a manufacturing cost that is about ⅓ lower than that of the existing GFRP.

The above description is merely an illustrative description of the technical idea of the present invention, and those skilled in the art will appreciate that various modifications and variations may be made without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to explain it, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

100: Type-C liquid hydrogen storage tank 10: Tank body
20: Internal tank 30: External tank
40: Vacuum space 50: Support structure
51: Wood block 52: Sheet metal
60: Tank Dome 70: Pillar Holder

Claims (17)

A tank body including an inner tank in the shape of a capsule for storing ultra-low temperature liquid hydrogen and an outer tank configured to surround the inner tank and be spaced apart from the inner tank by a certain distance;
A vacuum space formed between the inner tank and the outer tank;
A plurality of support structures connecting the inner tank and the outer tank; and
A tank dome connected to the upper part of one side of the tank body;
Type-C liquefied hydrogen storage tank with integrated support structure including. In the first paragraph,
A Type-C liquid hydrogen storage tank having an integrated support structure in which one side of the tank body is divided into a fixed part and the other side is divided into a sliding part. In the second paragraph,
A pillar holder that supports the plurality of support structures so that they are fixed to the outside of the inner tank and the inside of the outer tank in the above-mentioned fixed portion;
Type-C liquefied hydrogen storage tank with integrated support structure including: In the second paragraph,
A pillar holder that supports the plurality of support structures in the above sliding section so that they are fixed to the outside of the inner tank or the inside of the outer tank;
Type-C liquefied hydrogen storage tank with integrated support structure including: In the first paragraph,
The above plurality of support structures are,
wooden blocks; and
Sheet metal sealing the above wooden blocks;
Type-C liquefied hydrogen storage tank with integrated support structure including. In paragraph 5,
A Type-C liquid hydrogen storage tank having an integrated support structure in which one side of the above wooden block has been subjected to a chamfering operation. In paragraph 5,
A Type-C liquid hydrogen storage tank with an integrated support structure, wherein the above sheet metal is a cryogenic sheet metal. In Article 7,
A Type-C liquefied hydrogen storage tank with an integrated support structure, wherein the above sheet metal is either SUS304 or SUS316. In paragraph 5,
A Type-C liquefied hydrogen storage tank with an integrated support structure, wherein the thickness of the four sides of the above sheet metal is 1 mm to 2 mm. In Article 9,
A Type-C liquid hydrogen storage tank with an integrated support structure, wherein the upper and lower surfaces of the above-mentioned sheet metal have a thickness of 3 mm to 4 mm. In a method for manufacturing a support structure for a Type-C liquid hydrogen storage tank,
Steps for manufacturing sheet metal;
Steps to make a wooden block;
A step of performing a chamfering operation on one side of the above wooden block;
a step of inserting the wooden block into the above sheet metal; and
A step of welding the upper surface of the above sheet metal;
A method for manufacturing a support structure including: In Article 11,
The step of manufacturing the above sheet metal is a method for manufacturing a support structure in which the four side surfaces and the lower surface excluding the upper surface of the sheet metal are welded to manufacture the support structure in a form in which the upper surface is open. In Article 12,
A method for manufacturing a support structure, wherein the step of inserting the wooden block into the sheet metal is performed such that the surface of the wooden block on which the chamfering work was performed faces the upper surface of the sheet metal. In Article 11,
A method for manufacturing a support structure, wherein the step of manufacturing the above sheet metal comprises manufacturing the above sheet metal with a thickness of 1 mm to 2 mm on the four sides and a thickness of 3 mm to 4 mm on the upper and lower surfaces. In Article 11,
The above sheet metal is a method for manufacturing a support structure that is a sheet metal for cryogenic use. In Article 15,
A method for manufacturing a support structure, wherein the above sheet metal is either SUS304 or SUS316. A support structure manufactured by any one of the manufacturing methods of claims 11 to 16.