Gas storage container having safe supply means for gas and refrigerant

Abstract

The present invention relates to a gas storage container having a safe supply means for gas and refrigerant, and, more specifically, to a gas storage container having a safe supply means for safely supplying gas and a refrigerant to the gas storage container into which gaseous storage materials are inserted. The gas storage container having a safe supply means, according to one embodiment of the present invention, may comprise: an innermost shell forming a gas storage space in which a gas is stored, the gas storage space being filled with gaseous storage materials (hydrogen storage materials); a first supply line communicating with the gas storage space of the innermost shell, and supplying the gas from the outside; and a first discharge line for discharging the gas to the outside. The present specification has been established with the help of the InnoTown Development Project (the development of a prototype of a portable hydrogen storage container based on three-dimensional graphene hydrogen storage materials).

Description

Gas storage vessel equipped with gas and refrigerant safety supply means

[0001] The present invention relates to a gas storage container equipped with a safety supply means for gas and refrigerant, and more particularly, to a gas storage container equipped with a safety supply means for safely supplying gas and refrigerant to a gas storage container into which a gas storage material is inserted.

[0002] As industry develops, various gases are being used in industry. Representative gases used in industry include hydrogen, helium, oxygen, carbon monoxide, carbon dioxide, methane, nitrogen, and other inert gases.

[0003] For example, nitrogen is used in a variety of fields. It is used in packaging coffee, snacks, and dried fruit, as well as in the storage of beverages such as beer, wine, and fruit juice. It can perform functions such as preventing oxidation, preserving flavor, preserving freshness, repelling insects, and preventing bacterial growth.

[0004] Additionally, nitrogen can be used in plastic injection to maintain a vacuum state, shortening the cooling period during injection, and can be used in tire filling to reduce noise, reduce pieces, reduce uneven wear, and improve ride comfort.

[0005] In the case of gases, storage requires significant care due to their phase characteristics and inherent gas properties, and can incur significant costs. Accordingly, active research is being conducted on gas storage containers.

[0006] More specifically, using hydrogen gas as an example, rapid industrialization and population growth have led to the widespread use of fossil fuels. Currently, the majority (approximately 80%) of energy demand is met by fossil fuels such as oil, coal, and natural gas, raising global concerns about climate change, air and water pollution, and ozone layer depletion.

[0007] One way to address this is to convert fossil fuels to hydrogen fuel. Hydrogen gas is considered a "green fuel" and is attracting attention as a potential fossil fuel replacement. This is because hydrogen gas has the highest energy density per unit mass (142 MJ / kg) compared to all other fuels, is a simple and lightweight compound, and is one of the most abundant elements. Furthermore, hydrogen combustion produces only water vapor, so it does not cause environmental pollution.

[0008] That is, among the gases mentioned above, hydrogen gas is the gas for which industrial applicability and research are most actively being conducted, along with the international trend of implementing various policies and research for environmental protection.

[0009] A Fuel Cell Electric Vehicle (FCEV) is a vehicle that uses a fuel cell to power an electric motor. A representative example is a hydrogen fuel cell vehicle, or hydrogen electric vehicle. This vehicle uses hydrogen as a fuel cell and an electric motor to power the vehicle. The vehicle is powered by hydrogen stored in pressurized tanks at a hydrogen charging station.

[0010] Pressure vessels for storing high-pressure hydrogen gas are classified into four types: Type I, Type II, Type III, and Type IV, depending on the materials used and the composite material reinforcement method.

[0011] Type III pressure vessels are manufactured by wrapping carbon fiber or glass fibers in the circumferential and longitudinal directions around a metal liner. Type IV pressure vessels, aimed at reducing the vessel's weight, are manufactured by wrapping carbon fiber or glass fibers in the circumferential and longitudinal directions around a non-metallic liner. Carbon fiber-reinforced polymer (CFRP) exhibits sufficient mechanical properties as a primary load-bearing unit. Due to these advantages, Type III and Type IV pressure vessels are widely used in the hydrogen fuel cell vehicle industry.

[0012] A container for hydrogen storage is a container that compresses gaseous hydrogen at high pressure and stores it. The internal gas is exposed to an environment that ranges between -40℃ and 85℃ during charging and discharging, and it is a component that must secure durability for at least 5,000 repetitions in accordance with the target lifespan of 20 years.

[0013] In addition, it is necessary to develop high-pressure containers that take into account safety issues such as hydrogen leakage and deterioration due to pressure changes. In addition, vehicle containers used in hydrogen electric vehicles have a direct impact on fuel efficiency and price, so weight reduction and low cost are very important.

[0014] The US DOE has set a target hydrogen storage capacity per system weight of 1.8 kWh / kg for 2025, but the current commercial pressurized gas pressure vessel (Type IV commercial) is 1.46 kWh / kg, which is still below the target.

[0015] To meet industry standards for system gravimetric capacity, the internal pressure of Type IV pressure vessels must be increased to 70 MPa (700 bar). However, an explosion of a 700 bar hydrogen storage vessel could pose a significant risk to passengers in hydrogen vehicles.

[0016] Furthermore, maintaining a pressure of 700 bar requires the use of a significant amount of carbon fiber, which increases the production cost of pressure vessels. Furthermore, the energy required to compress hydrogen is approximately 10% of the gas's energy content, making compressing and storing hydrogen a significant energy drain.

[0017] In the container for hydrogen storage mentioned above, not only must the container itself be safe from hydrogen gas, but safety must also be ensured in the process of supplying hydrogen to the container in which hydrogen is stored. Therefore, a safety supply means is needed to prevent the container from being destroyed or exploded due to increased gas pressure in the line supplying hydrogen gas to the storage container and to supply it safely.

[0018] The present invention aims to provide a gas storage container equipped with a safety supply means for safely supplying a gas such as hydrogen gas and a refrigerant to a gas storage container into which a gas storage material is inserted.

[0019] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0020] A gas storage vessel equipped with a safety supply means according to one embodiment of the present invention includes an innermost shell forming a gas storage space in which gas is stored, wherein the gas storage space is filled with gas storage materials (hydrogen storage materials), and may include a first supply line communicating with the gas storage space of the innermost shell and supplying gas from the outside, and a first discharge line for discharging gas to the outside.

[0021] Preferably, the first supply line or the first discharge line may further include a first valve for controlling the amount of gas supplied or discharged.

[0022] Preferably, the first discharge line may further include a first safety valve that generates noise while discharging gas to the outside when the gas in the gas storage space rises above a preset pressure.

[0023] Preferably, the inner shell further includes an inner shell that surrounds the inner most shell to form a sealed space between the outer surface of the inner most shell, and the charged refrigerant is charged into the sealed space so that the temperature of the gas storage space maintains the vaporization point of the charged refrigerant when the pressure of the gas storage space is lower than a predetermined pressure, and may include a second supply line that is connected to the sealed space of the inner shell and supplies the charged refrigerant from the outside, and a second discharge line that discharges the refrigerant to the outside.

[0024] Preferably, the charged refrigerant can be phase-changed into a gaseous state (phase variation) in the sealed space so as to absorb the heat energy transferred to the inner shell by the latent heat of vaporization of the charged refrigerant.

[0025] Preferably, the second supply line or the second discharge line may further include a second valve for controlling the amount of charged refrigerant supplied or discharged.

[0026] Preferably, the second discharge line may further include a second safety valve that generates noise while discharging the phase-changed gas to the outside when the phase-changed charge refrigerant in the sealed space becomes higher than a preset pressure while the phase-changed charge refrigerant in the sealed space changes to a gaseous state in the sealed space.

[0027] Preferably, the length of the second supply line inserted into the inner shell can be formed longer than the length of the second discharge line inserted into the inner shell.

[0028] According to an embodiment of the present invention, a gas storage container having a hydrogen storage material inserted therein, which is made of a porous material that adsorbs gas in a gas storage space, can be used in a lower pressure range than a conventional pressurized gas storage container, while reducing the weight of the gas storage container and improving the system gravimetric capacity.

[0029] In addition, it is possible to provide a gas storage container in which a gas storage material is inserted, in which a refrigerant is filled between the innermost shell and the inner shell, a vacuum is formed between the inner shell and the outer shell, and an insulating material covers the outer surface of the inner shell, thereby blocking external heat energy from entering the gas storage space.

[0030] In addition, the amount of gas entering and exiting through the supply line and exhaust line formed externally in each of the innermost shell and inner shell can be controlled, and at the same time, destruction or explosion of the container due to high pressure can be prevented through a safety valve, thereby enhancing safety.

[0031] In addition, the innermost shell, the inner shell, and the outer shell are made of aluminum or stainless steel, and the first support and the second support are made of fiber reinforced plastics, thereby providing a gas storage container in which a gas storage material is inserted to block external heat energy from entering the gas storage space by heat conduction while maintaining the structural rigidity of the gas storage container.

[0032] In addition, various additional effects can be achieved through various embodiments of the present invention. These various effects of the present invention will be described in detail in each embodiment, or descriptions of effects easily understandable to those skilled in the art will be omitted.

[0033] FIG. 1 is a perspective view of a gas storage container into which a gas storage material is inserted according to one embodiment of the present invention.

[0034] Figure 2 is a cross-sectional perspective view of a gas storage container into which the gas storage material of Figure 1 is inserted.

[0035] Figure 3 is a cross-sectional perspective view showing a state in which a supply line and a discharge line are installed in the gas storage container of Figure 1.

[0036] Figure 4 is a cross-sectional view of Figure 3.

[0037] Figure 5 is a partial cross-sectional perspective view of a gas storage container into which the gas storage material of Figure 1 is inserted.

[0038] Fig. 6 is a cross-sectional view of a gas storage container into which the gas storage material of Fig. 1 is inserted.

[0039] Figure 7 is an enlarged view of part A of Figure 6.

[0040] Fig. 8 is a cross-sectional view showing the heat energy transfer of a gas storage container into which the gas storage material of Fig. 6 is inserted.

[0041] Figure 9 is a graph comparing the weight of a gas storage container into which a gas storage material is inserted according to one embodiment of the present invention and a conventional Type IV pressure container.

[0042] Below, with reference to the attached drawings, an embodiment of the present invention is described in detail so that a person having ordinary skill in the art to which the present invention pertains can easily practice it.

[0043] However, the present invention can be implemented in various different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts irrelevant to the description have been omitted, and similar parts have been designated with similar reference numerals throughout the specification.

[0044] In this specification, duplicate descriptions of identical components are omitted.

[0045] Additionally, when a component is referred to herein as being "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may be other components present in between. Conversely, when a component is referred to herein as being "directly connected" or "directly connected" to another component, it should be understood that there are no other components present in between.

[0046] Additionally, the terms used herein are only used to describe specific embodiments and are not intended to limit the present invention.

[0047] Also, in this specification, singular expressions may include plural expressions unless the context clearly indicates otherwise.

[0048] In addition, in this specification, it should be understood that terms such as “include” or “have” are intended to specify only the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0049] Also, in this specification, the term 'and / or' includes a combination of multiple listed items or any item among multiple listed items. In this specification, 'A or B' can include 'A', 'B', or 'both A and B'.

[0050]

[0051] According to embodiments of the present invention, a gas storage vessel having a gas storage material inserted therein can be used in a lower pressure range than a conventional pressurized gas storage vessel, is light in weight, and has an improved gas storage capacity per weight (system gravimetric capacity).

[0052] FIG. 1 is a perspective view of a gas storage container (10) into which a gas storage material (102) is inserted according to one embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the gas storage container (10) into which the gas storage material (102) of FIG. 1 is inserted. FIG. 3 is a cross-sectional perspective view showing a state in which a supply line and a discharge line are installed in the gas storage container of FIG. 1. FIG. 4 is a cross-sectional view of FIG. 3. FIG. 5 is a partial cross-sectional perspective view of the gas storage container (10) into which the gas storage material (102) of FIG. 1 is inserted.

[0053] Referring to FIGS. 1 to 5, a gas storage container (10) having a gas storage material (102) inserted therein according to one embodiment of the present invention is configured to store gas with a gas storage material (102) filled in a gas storage space (101), and includes an innermost shell (100), an inner shell (200), an outer shell (300), an insulator (400), a nozzle (500), and a support (600).

[0054] The gas stored in the gas storage vessel (10) may include at least one selected from the group consisting of hydrogen, helium, oxygen, carbon monoxide, carbon dioxide, methane, nitrogen, and other inert gases. That is, the gas storage vessel (10) may be used to store various gases that can be stored in the gas storage material (102).

[0055] As illustrated in FIGS. 2 to 5, the innermost shell (100) forms a gas storage space (101) therein. The innermost shell (100) includes a cylindrical shell (110) and a hemispherical head (120).

[0056] The cylindrical shell (110) forms a cylindrical shape. The cylindrical shell (110) is formed to be elongated in one direction. The hemispherical head (120) literally forms a hemispherical shape. The hemispherical heads (120) are provided at each of the longitudinal ends of the cylindrical shell (110). A nozzle (500) is coupled to the hemispherical head (120). The nozzle (500) forms a passage through which gas moves. Although not shown, a boss part surrounding the nozzle (500) may be formed on the hemispherical head (120).

[0057] The innermost shell (100) may be made of aluminum or stainless steel. Aluminum has relatively higher thermal conductivity and is lightweight compared to stainless steel. Stainless steel has relatively superior structural rigidity compared to aluminum and is widely used in industry, offering advantages in handling and processing. Accordingly, either aluminum or stainless steel may be selected depending on the characteristics of the gas stored in the gas storage vessel (10).

[0058] Alternatively, the innermost shell (100) may include a liner made of a non-metallic material and a fiber-reinforced composite material. The liner may be manufactured by winding the outer surface of the liner with a fiber-reinforced composite material to maintain the sealing and shape of the contents. The liner may be made of a high-density polyethylene (HDPE) material.

[0059] A gas storage material (102) is filled in the gas storage space (101). The gas storage material (102) may be formed of a porous material. Additionally, the gas storage material (102) may exist in the form of a plurality of powders.

[0060] For example, the gas storage material (102) may be a material capable of adsorbing gas, such as zeolites, activated carbon, porous carbon, porous graphene (three-dimensional graphene), or metal organic frameworks (MOFs).

[0061] The storage capacity of a porous medium can be determined primarily by its surface area, pore size, and pore volume. Furthermore, lowering the temperature or increasing the pressure can improve gas adsorption by microporous storage materials.

[0062] Gas physical absorption has excellent reversibility, low cost, and high storage capacity. Furthermore, at the same temperature and pressure, physical absorption can generate a larger gas capacity than compression methods. In other words, gas adsorption using microporous storage materials can store the same amount of gas at lower pressures or in smaller volumes than compression methods. Therefore, gas adsorption using microporous storage materials can enhance the safety of gas storage containers (10) and the freedom of tank design.

[0063] For example, looking at hydrogen gas, MOF-210 is reported to exhibit 14.31 wt% hydrogen adsorption under 77 K and 70 bar conditions. And NU-100 is reported to exhibit 14.08 wt% hydrogen adsorption under 77 K and 70 bar conditions. And DUT32 is reported to exhibit 14.21 wt% hydrogen adsorption under 77 K and 80 bar conditions. And NU-1501-Al is reported to exhibit 14.5 wt% hydrogen adsorption under 77 K and 100 bar conditions.

[0064] As illustrated in FIGS. 2 to 5, the inner shell (200) forms a shape surrounding the innermost shell (100). The inner shell (200) includes a cylindrical shell (210) and a hemispherical head (220).

[0065] The cylindrical shell (210) forms a cylindrical shape. The cylindrical shell (210) is formed to be elongated in one direction. The hemispherical head (220) literally forms a hemispherical shape. The hemispherical heads (220) are provided at each of the longitudinal ends of the cylindrical shell (210). A nozzle (500) is coupled to the hemispherical head (220). The nozzle (500) forms a passage through which gas moves. Although not shown, a boss part surrounding the nozzle (500) may be formed on the hemispherical head (220).

[0066] That is, the inner shell (200) may be provided with a shape corresponding to the innermost shell (100), and may be provided with an overall size larger than the innermost shell (100) and may be arranged to be spaced apart from each other by a predetermined interval.

[0067] The inner shell (200) may be made of aluminum or stainless steel. Aluminum has relatively higher thermal conductivity and is lightweight compared to stainless steel. Stainless steel has relatively superior structural rigidity compared to aluminum and is widely used in industry, offering advantages in handling and processing. Accordingly, either aluminum or stainless steel may be selected depending on the characteristics of the gas stored in the gas storage vessel (10).

[0068] The outer surface of the innermost shell (100) and the inner surface of the inner shell (200) are spaced apart at a constant interval. A sealed space (201) is formed between the outer surface of the innermost shell (100) and the inner surface of the inner shell (200). The sealed space (201) forms a space sealed from the outside.

[0069] Fig. 6 is a cross-sectional view of a gas storage container (10) into which the gas storage material (102) of Fig. 1 is inserted. Fig. 7 is an enlarged view of part A of Fig. 6.

[0070] Fig. 8 is a cross-sectional view showing the transfer of thermal energy in a gas storage vessel (10) into which the gas storage material (102) of Fig. 6 is inserted. The solid arrows in Fig. 8 indicate the transfer of thermal energy by conduction. The bold arrows in Fig. 8 indicate the transfer of thermal energy by radiation. The dotted arrows in Fig. 8 indicate vaporized refrigerant.

[0071] As illustrated in FIGS. 6 and 8, a charge refrigerant (202) is charged into a sealed space (201). The charge refrigerant (202) is charged in a state in which it can change into a gaseous state in the sealed space (201). The charge refrigerant (202) has its own boiling point, and even if external heat energy is transferred to the inner shell (200), the heat energy transferred to the inner shell (200) can be absorbed by the latent heat of vaporization of the charge refrigerant (202). Accordingly, the temperature of the gas storage space (101) can be maintained at about the boiling point of the charge refrigerant (202).

[0072] The charge refrigerant (202) may include one or more liquefied refrigerants selected from the group consisting of liquid nitrogen, liquid argon, halocarbon refrigerants, hydrocarbon refrigerants, and ammonia, and a refrigerant suitable for the purpose of the invention may be selected and used among the various types of liquefied refrigerants described above. At this time, in the case of liquid nitrogen, the boiling point is about 77K, so that the temperature of the gas storage space (101) can be maintained at about 77K. In the case of liquid argon, the boiling point is about 87K, so that the temperature of the gas storage space (101) can be maintained at about 87K.

[0073] The charging refrigerant (202) may be selected as appropriate depending on the characteristics of the gas stored in the gas storage space (101), the size of the gas storage container (10), and the location where the gas storage container (10) is installed.

[0074] In addition, the gas storage space (101) can be maintained at a pressure below a predetermined level for the safety of the gas stored in the gas storage space (101) and the safety of the charged refrigerant (202) charged in the sealed space (201).

[0075] That is, the predetermined pressure may be the allowable pressure of the gas storage container (10) and may be set to 200 bar or less. Specifically, the pressure of the gas storage space (101) may be maintained at 200 bar or less, thereby increasing the safety of the entire gas storage container (10).

[0076] Preferably, the predetermined pressure may be set to 100 bar or less. Accordingly, gas and gas storage material (102) can be efficiently and stably placed in the gas storage space (101), and the charged refrigerant (202) can be stably placed in the sealed space (201).

[0077] Meanwhile, gas is charged into the gas storage space (101) through the nozzle (500). The gas charged into the gas storage space (101) is adsorbed onto the gas storage material (102). For example, if the gas storage space (101) is charged with hydrogen gas and the charging refrigerant (202) is provided as liquid nitrogen, the type of the gas storage material (102) can be selected from any one of MOF-210, NU-100, DUT 32, and NU-1501-Al.

[0078] At this time, the gas storage space (101) can maintain a temperature of 77 K under a pressure condition of 100 bar or less. That is, when the pressure of the gas storage space (101) is 100 bar or less, the temperature of the gas storage space (101) can be maintained at the vaporization point of liquid nitrogen (approximately 77 K).

[0079]

[0080] In addition, it may include a first supply line (130) that is connected to the gas storage space (101) of the innermost shell (100) and supplies gas from the outside, and a first discharge line (140) that discharges gas to the outside.

[0081] The first supply line (130) is defined as a passage for supplying at least one selected from the group consisting of hydrogen, helium, oxygen, carbon monoxide, carbon dioxide, methane, nitrogen and other inert gases stored in the gas storage container (10) from the outside to the gas storage space (101) of the innermost shell (100).

[0082] The first supply line (130) may be configured as a hollow pipe shape with a predetermined diameter, may be formed to penetrate the innermost shell (100) so that the outside and the gas storage space (101) are connected, and may be configured to be connected to a nozzle (500) for filling gas into the gas storage space (101).

[0083] In addition, a first discharge line (140) having the same structure and shape as the first supply line (130) may be formed to discharge gas inside the innermost shell (100) to the outside. The first discharge line (140) may be configured to discharge gas stored in the gas storage space (101) to the outside, and may be positioned to be spaced apart from the first supply line (130) by a predetermined distance. However, in order to manage the line formed in communication with the outside, it may be formed to share the same movement path as the first supply line (130), and the gas supplied and discharged may be controlled through a valve described later.

[0084] Here, a first valve (131, 141) may be further included to control the amount of gas supplied or discharged, which is provided in the first supply line (130) or the first discharge line (140).

[0085] The first valve (131, 141) may be configured as a valve for controlling the amount of gas flowing into the gas storage space (101) from the outside through the first supply line (130), and as a valve for controlling the amount of gas discharged from the inside of the gas storage space (101) to the outside through the first discharge line (140).

[0086] The first valve (131, 141) may be configured as a needle valve for protecting pipes and pressurized equipment from sudden pressure changes that may affect the line when the state of motion of the gas flowing in the supply line suddenly changes, thereby protecting the line.

[0087] In addition, a first safety valve (142) may be further included, which is provided in the first discharge line (140) and generates noise while discharging gas to the outside when the gas in the gas storage space (101) rises above a preset pressure.

[0088] The first safety valve (142) is configured to prevent in advance the risk of explosion, which exists due to the nature of the inert gas during the process of flowing into and exhausting the gas storage vessel (10) where the inert gas is stored. The first safety valve (142) may be installed adjacent to one end connected to the outside in the first discharge line (140), and may be configured to discharge the gas to the outside when the internal pressure rises above a preset pressure to prevent the gas storage vessel (10) from being destroyed or exploded as the pressure of the gas inside the innermost shell (100) increases.

[0089] In one embodiment, the first safety valve (142) is not normally operated, but when the gas pressure inside the gas storage space (101) increases to, for example, (100 bar + 10 bar) or higher, the first safety valve (142) opens and discharges the gas to the outside through the first discharge line (140), and at the same time, a noise indicating the discharge of the gas is generated to notify the manager that the gas is being discharged.

[0090] By means of the above-described configuration, safety can be improved by controlling the amount of gas flowing into and out of the gas storage container (10) from the outside, and in particular, by automatically discharging gas to the outside before the container explodes through the safety valve, danger can be prevented in advance, and noise can be generated to notify the manager of the situation in which gas is being discharged.

[0091]

[0092] Next, it may include a second supply line (230) that is connected to the sealed space (201) of the inner shell (200) and supplies a charge refrigerant (202) from the outside, and a second discharge line (240) that discharges the refrigerant to the outside.

[0093] The overall configuration or function of the second supply line (230) and the second discharge line (240) may be formed in the same or similar form as the first supply line (130) or the first discharge line (140), and are configured to communicate with the outside and the sealed space (201) of the inner shell (200) rather than the innermost shell (100).

[0094] The second supply line (230) and the second discharge line (240) are formed as passages through which the charge refrigerant (202) flows, and the second supply line (230) and the second discharge line (240) can be arranged in parallel on both sides based on the first supply line (130) or the first discharge line (140). Accordingly, the charge refrigerant (202) introduced from the outside into the inner shell (200) through the second supply line (230) can circulate along the sealed space (201) and be discharged to the outside through the second discharge line (240).

[0095] Here, the length of the second supply line (230) inserted into the inner shell (200) may be formed longer than the length of the second discharge line (240) inserted into the inner shell (200). This is to supply the refrigerant from the second supply line (230) inserted relatively deeply, thereby reducing the amount of refrigerant wasted in the phase change during charging and discharging only the phase-changed gas, thereby increasing efficiency and preventing problems from occurring.

[0096] In addition, a second valve (231, 241) may be further included to control the amount of charge refrigerant (202) supplied or discharged, which is provided in the second supply line (230) or the second discharge line (240). The second valve (231, 241), like the first valve (131, 141), is configured to control the amount of charge refrigerant (202) supplied or discharged.

[0097] The aforementioned charge refrigerant (202) can be configured to change into a gaseous state in a sealed space (201) so as to absorb the heat energy transferred to the inner shell (200) by the latent heat of vaporization of the charge refrigerant (202). When the charge refrigerant (202) absorbs the heat energy and vaporizes into a gaseous state, the pressure within the sealed space (201) increases due to this gas, making it difficult to supply additional refrigerant, and if the pressure increases excessively, the container may be destroyed. To prevent this, the destruction of the container can be prevented in advance by controlling the amount of the charge refrigerant (202) introduced or discharged through the second valve (231, 241).

[0098] In addition, when the charged refrigerant (202) changes into a gaseous state in a sealed space (201) and the pressure of the charged refrigerant (202) in the sealed space (201) increases above a preset pressure, the manager can be aware that the refrigerant is being discharged by inducing discharge of the refrigerant through the second safety valve (242) provided in the second discharge line (240).

[0099] In particular, as the pressure of the gas may increase rapidly while changing phases, the second safety valve (242) installed adjacent to the external end of the second discharge line (240) discharges the gas while generating noise, thereby allowing the manager to confirm that the pressure inside the container is currently high, and preventing the container from being destroyed or exploded.

[0100]

[0101] As illustrated in FIGS. 2 to 4, the outer shell (300) forms a shape that surrounds the inner shell (200). The outer surface of the outer shell (300) is exposed to the external environment. The outer shell (300) includes a cylindrical shell (310) and a hemispherical head (320).

[0102] The cylindrical shell (310) forms a cylindrical shape. The cylindrical shell (310) is formed to be elongated in one direction. The hemispherical head (320) literally forms a hemispherical shape. The hemispherical heads (320) are provided at each of the longitudinal ends of the cylindrical shell (310). A nozzle (500) is coupled to the hemispherical head (320). Although not shown, a boss part surrounding the nozzle (500) may be formed on the hemispherical head (320).

[0103] That is, the outer shell (300) may be provided with a shape corresponding to the inner shell (200), and may be provided with an overall size larger than the inner shell (200) and may be arranged to be spaced apart from each other by a predetermined interval.

[0104] The outer shell (300) may be made of aluminum or stainless steel. Aluminum has relatively higher thermal conductivity and is lightweight compared to stainless steel. Stainless steel has relatively superior structural rigidity compared to aluminum and is widely used in industry, offering advantages in handling and processing. Accordingly, either aluminum or stainless steel may be selected depending on the characteristics of the gas stored in the gas storage vessel (10).

[0105] The outer surface of the outer shell (300) and the inner surface of the inner shell (200) are spaced apart at a constant interval. An insulating space (301) is formed between the outer surface of the outer shell (300) and the inner surface of the inner shell (200). The insulating space (301) forms a space sealed from the outside.

[0106] As shown in Fig. 6, the insulating space (301) forms a vacuum. Although not shown, a port connected to a vacuum pump is provided in the insulating space (301). The insulating space (301) is 10 -2 10 in Pa -5A degree of vacuum of up to Pa is formed. Therefore, heat conduction by gas in the insulating space (301) is blocked.

[0107] The outer surface of the outer shell (300) is exposed to the external environment. Even if the temperature of the outer shell (300) rises due to heat energy transmitted from the outside, heat transfer by convection and conduction of gas in the insulating space (301) is blocked.

[0108] As illustrated in FIGS. 4 and 5, an insulating material (400) is provided in the insulating space (301). The insulating material (400) is configured to block heat inflow into the inner shell (200). The insulating material (400) forms a shape that covers the outer surface of the inner shell (200). The insulating material (400) is spaced apart from the inner surface of the outer shell (300).

[0109] For example, the insulation (400) may include a plurality of spacers (410) and a plurality of foils (420). The spacers (410) may be made of glass wool. The foils (420) may be made of aluminum foil (420). The spacers (410) and the foils (420) form a structure in which they are alternately laminated.

[0110] 10 of the insulation space (301) -2 10 in Pa -5 A vacuum of up to Pa effectively prevents heat conduction of the gas in the insulating space (301), but may not block radiation heat transfer in the insulating space (301). Accordingly, the insulating material (400) retroreflects 95 to 98% of the infrared radiation from the outer shell (300), thereby minimizing radiation heat transfer to the inner shell (200).

[0111] As illustrated in FIGS. 2 to 6, the support (600) includes a first support (610) and a second support (620). In FIGS. 5, 6, and 7, the illustration of the first support (610) is omitted to clarify the level of the charged refrigerant (202).

[0112] As illustrated in Fig. 2, the first support (610) connects the innermost shell (100) and the inner shell (200) in a sealed space (201). The first support (610) includes a shell support (611) and a head support (612).

[0113] The shell support (611) connects the cylindrical shell (110) of the innermost shell (100) and the cylindrical shell (210) of the inner shell (200) in the sealed space (201). The shell support (611) may be formed in a bar shape. The shell support (611) may be provided in multiple numbers. The multiple shell supports (611) may be arranged at regular intervals along the circumferential direction.

[0114] The head support (612) connects the hemispherical head (120) of the innermost shell (100) and the hemispherical head (220) of the inner shell (200) in the sealed space (201). The head support (612) may be formed in a bar shape.

[0115] The stress generated in the innermost shell (100) by the pressure of the gas storage space (101) is distributed to the innermost shell (200) through the first support (610). Therefore, deformation of the innermost shell (100) by the pressure of the gas storage space (101) is suppressed.

[0116] The first support (610) is made of fiber reinforced plastics. For example, the first support (610) is made of GFRP (glass fiber reinforced plastic).

[0117] The thermal conductivity of aluminum is 191 kcal / mh℃. In contrast, the thermal conductivity of GFRP is 0.24 kcal / mh℃, which is 0.12% of the thermal conductivity of aluminum. Therefore, heat conduction through the first support (610) in the enclosed space (201) is minimized.

[0118] Additionally, the thermal conductivity of stainless steel is 13.97 kcal / mh℃. In contrast, the thermal conductivity of GFRP is 0.24 kcal / mh℃, which is 1.7% of the thermal conductivity of stainless steel. Therefore, heat conduction through the first support (610) in the sealed space (201) is minimized.

[0119] As illustrated in Fig. 4, the second support (620) connects the inner shell (200) and the outer shell (300) in the insulating space (301). The second support (620) includes a shell support (621) and a head support (622).

[0120] The shell support (621) connects the cylindrical shell (110) of the inner shell (200) and the cylindrical shell (210) of the outer shell (300) in the insulating space (301). The shell support (621) may be formed in a bar shape. The shell support (621) may be provided in multiple numbers. The multiple shell supports (621) may be arranged at regular intervals along the circumferential direction.

[0121] The head support (622) connects the hemispherical head (120) of the inner shell (200) and the hemispherical head (220) of the outer shell (300) in the insulating space (301). The head support (622) may be formed in a bar shape.

[0122] The stress generated in the innermost shell (100) by the pressure of the gas storage space (101) is distributed to the inner shell (200) and the outer shell (300) through the first support (610) and the second support (620). Therefore, deformation of the innermost shell (100) by the pressure of the gas storage space (101) is suppressed.

[0123] The second support (620) is made of fiber reinforced plastics. For example, the second support (620) is made of GFRP (glass fiber reinforced plastic).

[0124] The thermal conductivity of aluminum is 191 kcal / mh℃. In contrast, the thermal conductivity of GFRP is 0.24 kcal / mh℃, which is 0.12% of the thermal conductivity of aluminum. Therefore, heat conduction through the second support (620) in the insulating space (301) is minimized.

[0125] Additionally, the thermal conductivity of stainless steel is 13.97 kcal / mh℃. In contrast, the thermal conductivity of GFRP is 0.24 kcal / mh℃, which is 1.7% of the thermal conductivity of stainless steel. Therefore, heat conduction through the second support (620) in the insulating space (301) is minimized.

[0126] Meanwhile, for the convenience of explanation, the following description will be made by comparing a conventional container with a gas storage container (10) according to embodiments of the present invention, taking as an example a case where hydrogen gas is stored in a gas storage container (10). That is, the gas stored in the gas storage container (10) is hydrogen, the gas storage material (102) may be a hydrogen storage material, and the charging refrigerant (202) may be liquid nitrogen.

[0127] To meet industry standards for system gravimetric capacity, the internal pressure of Type IV pressure vessels must be increased to 70 MPa (700 bar). However, the energy required to compress hydrogen is approximately 10% of the gas's energy content, resulting in a significant energy consumption for compressing and storing hydrogen.

[0128] Since all gases, including hydrogen, generate heat when compressed, Type IV pressure vessels require pre-cooling of the gas to prevent overheating during compression filling. However, pre-cooling requires 1.8 to 3.6 wt% of energy.

[0129] In addition, if the 700 bar gas storage tank (10) of the conventional TypeⅣ pressure vessel explodes, passengers riding in a hydrogen car may be very dangerous.

[0130] In addition, the conventional Type IV pressure vessel has the problem that a significant amount of carbon fiber must be used to maintain a pressure of 700 bar, which significantly increases the load of the pressure vessel and increases the production cost of the pressure vessel.

[0131] Figure 7 is a graph comparing the weight of a gas storage container (10) into which a gas storage material (102) according to one embodiment of the present invention is inserted and a conventional Type IV pressure container.

[0132] In Fig. 7, R141, R146, R151, R156, R161, and R166 represent gas storage vessels (10) that use different gas storage materials (102) such as zeolites, activated carbon, porous carbon, porous graphene (three-dimensional graphene), and metal organic frameworks (MOFs). In Fig. 7, R166-CF represents a gas storage vessel (10) in which the innermost shell (100) is manufactured using a liner made of HDPE material and a fiber-reinforced composite material. In Fig. 7, TypeⅣ represents a conventional TypeⅣ pressure vessel.

[0133] According to one embodiment of the present invention, a gas storage vessel (10) having a gas storage material (102) inserted therein requires only a maximum pressure of 80 bar to store hydrogen in the gas storage material (102) within the innermost shell (100). Therefore, since the pressure is approximately 9 times lower than that required for a conventional Type IV pressure vessel, the risk of explosion of the gas storage vessel (10) is significantly reduced.

[0134] In addition, the gas storage container (10) in which the gas storage material (102) according to one embodiment of the present invention is inserted has a material cost that is reduced by about 30 to 50% compared to a conventional Type IV pressure container manufactured by winding carbon fiber or glass fiber over a liner.

[0135] In addition, the gas storage vessel (10) into which the gas storage material (102) according to one embodiment of the present invention is inserted can reduce the system load by approximately 50 to 60% compared to the conventional TypeⅣ pressure vessel. Therefore, the gas storage vessel (10) into which the gas storage material (102) according to one embodiment of the present invention is inserted has an improved system gravimetric capacity compared to the conventional TypeⅣ pressure vessel.

[0136] According to an embodiment of the present invention, a gas storage material (102) made of a porous material that adsorbs hydrogen is filled in a gas storage space (101), thereby providing a gas storage container (10) in which a gas storage material (102) is inserted, which can be used in a lower pressure range than a conventional pressurized gas type gas storage container (10), while reducing the weight of the gas storage container (10) and improving the system gravimetric capacity per weight of the system.

[0137] In addition, according to an embodiment of the present invention, a gas storage container (10) can be provided in which a charge refrigerant (202) is charged between an innermost shell (100) and an inner shell (200), a vacuum is formed between the inner shell (200) and the outer shell (300), and a gas storage material (102) is inserted so as to block external heat energy from entering the gas storage space (101) by covering the outer surface of the inner shell (200) with an insulating material (400).

[0138] In addition, according to an embodiment of the present invention, the innermost shell (100), the inner shell (200), and the outer shell (300) are made of aluminum or stainless steel, and the first support (610) and the second support (620) are made of fiber reinforced plastics, thereby providing a gas storage container (10) in which a gas storage material (102) is inserted to block external heat energy from entering the gas storage space (101) by heat conduction while maintaining the structural rigidity of the gas storage container (10).

[0139] Meanwhile, referring again to FIGS. 2 to 4, a gas storage container (10) according to one embodiment of the present invention may be provided with a triple-wall structure including an innermost shell (100), an inner shell (200), and an outer shell (300).

[0140] That is, the innermost shell (100) has a gas storage space (101) formed therein, the gas storage space (101) forms a primary space, and gas and gas storage material (102) can be placed in the primary space.

[0141] The inner shell (200) forms a sealed space (201) between the outer surface of the innermost shell (100), and the sealed space (201) forms a secondary space, and a charge refrigerant (202) can be placed in the secondary space.

[0142] The outer shell (300) forms an insulating space between the outer surface of the inner shell (200), and the insulating space (301) forms a tertiary space, and an insulating material (400) can be placed in the tertiary space.

[0143] In other words, the gas storage container (10) may have a triple wall structure in which the innermost shell (100) may form the primary wall, the inner shell (200) may form the secondary wall, and the outer shell (300) may form the tertiary wall, and the gas storage space (101) may form the primary space, the sealed space (201) may form the secondary space, and the insulating space (301) may form the tertiary space.

[0144] In addition, the internal volume of the space composed of the innermost shell (100) can be set to 10 mL to 300 L. Accordingly, the structural safety of the gas storage container (10) can be secured to the maximum extent possible while the weight of the gas storage container (10) can be minimized, making it easy to transport and store, and the manufacturing cost of the gas storage container (10) can also be minimized.

[0145] While representative embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that various modifications to the above-described embodiments are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims set forth below but also by equivalents thereof.

Claims

1. Includes an innermost shell that forms a gas storage space where gas is stored, The above gas storage space is filled with gas storage materials (hydrogen storage materials), A gas storage vessel characterized by including a first supply line communicating with the gas storage space of the innermost shell and supplying gas from the outside and a first discharge line discharging the gas to the outside.

2. In paragraph 1, A gas storage vessel characterized in that it further includes a first valve provided in the first supply line or the first discharge line and for controlling the amount of gas supplied or discharged.

3. In paragraph 1, A gas storage vessel characterized in that it further includes a first safety valve provided in the first discharge line and generating noise while discharging gas to the outside when the gas in the gas storage space rises above a preset pressure.

4. In paragraph 1, It further includes an inner shell surrounding the inner most shell to form a sealed space between the outer surface of the inner most shell, When the pressure of the gas storage space is below a predetermined pressure, the charge refrigerant is charged into the sealed space so that the temperature of the gas storage space maintains the vaporization point of the charge refrigerant. A gas storage container characterized by including a second supply line communicating with the sealed space of the inner shell and supplying a charged refrigerant from the outside and a second discharge line discharging the refrigerant to the outside.

5. In paragraph 4, A gas storage container having a gas storage material inserted therein, characterized in that the charged refrigerant is capable of phase variation into a gaseous state in the sealed space so as to absorb the heat energy transferred to the inner shell by the latent heat of vaporization of the charged refrigerant.

6. In paragraph 5, A gas storage vessel characterized in that it further includes a second valve provided in the second supply line or the second discharge line and for controlling the amount of charged refrigerant supplied or discharged.

7. In paragraph 6, A gas storage container characterized in that it further includes a second safety valve provided in the second discharge line, and when the charged refrigerant changes into a gaseous state in a sealed space and the charged refrigerant that has changed into a gaseous state within the sealed space rises above a preset pressure, the gas that has changed into a gaseous state is discharged to the outside while generating noise.

8. In paragraph 1, A gas storage container having a gas storage material inserted therein, characterized in that the gas storage material is made of a porous material that absorbs gas.

9. In paragraph 4, It further includes an outer shell surrounding the inner shell to form an insulating space between the outer surface of the inner shell, A gas storage container having a gas storage material inserted therein, characterized in that the insulating space forms a vacuum to block heat conduction by gas in the insulating space.

10. In paragraph 9, A gas storage container having a gas storage material inserted therein, characterized in that an insulating material covering the outer surface of the inner shell and spaced apart from the inner surface of the outer shell is provided in the insulating space.

11. In paragraph 4, A gas storage vessel characterized in that the length of the second supply line inserted into the inner shell is formed longer than the length of the second discharge line inserted into the inner shell.

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