High heat storage tank

Abstract

The present invention relates to a thermal storage tank for storing a high-insulation fluid, such as water or oil, comprising: an inner container having a storage space formed therein for storing the fluid; a first outer container formed to accommodate the inner container and spaced apart from the inner container; a first insulating space formed as a vacuum space between the inner container and the first outer container; and a selective absorption coating surface disposed on the outer surface of the first outer container, having high absorption and emissivity in the visible light region and low absorption and emissivity in the infrared region. It has the advantage of improving heat collection efficiency by reducing heat loss, and has the advantage of maintaining high efficiency under heat production conditions at higher temperatures compared to conventional collectors.

Description

Technology Field

[0001] The present invention relates to a thermal storage tank, and more specifically, to a highly insulating thermal storage tank for storing fluids such as high-temperature water or oil. Background Technology

[0002] Recently, interest in renewable energy for reducing carbon emissions has been increasing. Among renewable energies, solar thermal technology utilizes solar radiation by converting it into heat; thanks to high-efficiency collection technology, heat collection has become possible at temperatures exceeding 150°C. Consequently, thermal storage tanks are required to store heat with high efficiency at these enhanced collection levels.

[0003] FIG. 1 is an example of a conventional thermal storage tank. The illustrated thermal storage tank is a partial one with the top and bottom omitted. The top and bottom are formed with a bottom surface or a cover is placed to seal the internal space. Referring to FIG. 1, it includes an inner container (100) in which a storage space (110) is formed to store a fluid, a first outer container (200) formed to accommodate the inner container and spaced apart from the inner container, and a first insulation space (210) formed as a vacuum space between the inner container and the first outer container. Conventional thermal storage tanks reduce heat loss of the fluid by forming a vacuum layer such as the first insulation space.

[0004] Conventional heat storage tanks have the disadvantage of high heat loss when storing fluids above 150°C due to the relatively high heat transfer coefficient of the insulation. To address this, the insulation must be thickened, which results in the disadvantage of occupying a larger space along with the heat storage tank. Although heat transfer oils are widely used as heat transfer media for storing heat above 150°C, problems arise where the temperature drop is very high due to low heat storage density and ratio. However, as heat collection performance improves and the temperature of the fluid stored in the internal container rises, there is a demand for heat storage tanks that can maximize the reduction of heat loss. The problem to be solved

[0005] Accordingly, the present invention was devised to solve the problems of the prior art as described above. When storing fluids of 150°C or higher using a conventional thermal storage tank, heat loss is high, and when the thermal storage tank is modified to reduce heat loss, the problem of occupying a larger space occurs. Therefore, the invention provides a highly insulated thermal storage tank that reduces heat loss and increases thermal storage efficiency. means of solving the problem

[0006] The present invention comprises an inner container having a storage space formed to store a fluid, a first outer container formed to accommodate the inner container and spaced apart from the inner container, and a first insulation space formed as a vacuum space between the inner container and the first outer container, wherein a filler having heat storage performance is disposed therein.

[0007] Additionally, it includes a coating surface having low emissivity disposed on the outer surface of the inner container, or further includes a coating surface having low emissivity disposed on the inner surface of the first outer container.

[0008] In addition, the filler is formed in the form of pellets to form voids in the first insulation space, and is characterized by being formed from one or more types of recycled aggregate and PCM (phase change material).

[0009] In addition, the outer surface of the first outer container further includes a selective absorption coating surface having a high absorption rate and emissivity in the visible light region and a low absorption rate and emissivity in the infrared region to absorb solar radiation.

[0010] Additionally, it includes a transparent body made of a material that transmits sunlight and is spaced apart from the outer surface of the first outer container, and an air layer formed between the first outer container and the transparent body.

[0011] Additionally, the filler is formed from one or more types of recycled aggregate and PCM (phase change material), and includes a first outer container that is accommodated and a second outer container formed to be spaced apart from the first outer container, and a second insulating space formed as a vacuum space between the first outer container and the second outer container.

[0012] Additionally, it further includes a transparent body made of a material that transmits sunlight and is spaced apart from the outer surface of the second outer container, and an air layer formed between the second outer container and the transparent body.

[0013] Additionally, it includes a selective absorption coating surface disposed on the outer surface of the second outer container, having high absorption and emissivity in the visible light region and low absorption and emissivity in the infrared region.

[0014] In addition, the second insulation space is formed in a pellet shape to form voids, and is characterized by further arranging a filler consisting of one or more types of recycled aggregate and PCM (phase change material).

[0015] In addition, the filler placed in the first insulation space and the filler placed in the second insulation space are characterized by having different types or mixing ratios. Effects of the invention

[0016] The present invention has the advantage of improving heat collection efficiency by reducing heat loss generated in transparent materials, etc., and has the advantage of maintaining high efficiency under heat production conditions at higher temperatures compared to conventional collectors.

[0017] In addition, since it is possible to produce steam with high efficiency while maintaining high efficiency even when collecting heat at a production temperature of 150°C or higher, it has the advantage of contributing to the reduction of carbon emissions in industrial processes and district heating by connecting it to industrial heating processes or district heating piping.

[0018] In addition, it has the advantage of contributing to the improvement of the efficiency of heat-driven refrigeration systems by enabling high-efficiency heat collection and heat production and supply as a heat source for heat-driven chillers.

[0019] In addition, if a high-efficiency collector is used at the 80°C level where conventional collectors are commonly applied, it is possible to collect heat with higher efficiency, which has the advantage of improving economic efficiency. Brief explanation of the drawing

[0020] Figure 1 is a conventional thermal storage tank. FIG. 2 is a partial cross-sectional view of the first embodiment. FIG. 3 is an example diagram of the application of the first embodiment. FIG. 4 is a second embodiment of the present invention. FIG. 5 is a partial cross-sectional view of the second embodiment. FIG. 6 is an example of the application of the second embodiment. Specific details for implementing the invention

[0021] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to specific embodiments, and it should be understood that it includes all modifications that fall within the spirit and scope of the invention.

[0022] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains.

[0023] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0024] A high-insulation thermal storage tank according to an embodiment of the present invention will be described in detail below with reference to the attached drawings.

[0025] FIG. 2 is an enlarged view of the first embodiment. Referring to FIG. 2, the illustrated high-insulation thermal storage tank is a partial form with the top and bottom omitted. The top and bottom are formed with a bottom surface or a cover is placed to seal the internal space. Referring to FIG. 2, the tank includes an inner container (100) having a storage space (110) formed to store fluid, a first outer container (200) formed to accommodate the inner container (100) and spaced apart from the inner container (100), and a first insulation space (210) formed as a vacuum space between the inner container (100) and the first outer container (200).

[0026] The objective of the present invention is to accommodate a fluid of 150°C or higher using an improved heat collection technology and to reduce heat loss, wherein the inner container (100) is formed of a material that is not deformed by a fluid of 150°C or higher. The inner container (100) has an inlet and an outlet formed at the top or bottom, and a high-temperature fluid is introduced and stored.

[0027] The first outer container (200) accommodates the inner container (100) inside. The outer surface of the first outer container (200) is exposed to the outside. The inner container (100) and the first outer container (200) are spaced apart to form a first insulation space (210). The first insulation space (210) may be connected to a vacuum pump (not shown) to form a vacuum. Since the inner container (100) does not come into direct contact with the outside, heat loss due to conduction and heat loss due to convection through the first insulation space (210) formed as a vacuum are reduced. As the spacing (width of the first insulation space) between the inner container (100) and the first outer container (200) increases, the insulation performance improves, and the spacing is formed to satisfy the required insulation performance.

[0028] In addition, the outer surface of the inner container (100) can be formed of a material with low thermal emissivity. By reducing the thermal emissivity due to high internal temperature, heat loss can be reduced.

[0029] In addition, the first embodiment is characterized by forming a selective absorption / radiation coating surface on the outer surface of the first outer container (200) to reduce heat loss. The selective absorption coating surface has high absorption / radiation characteristics in the visible light region and low absorption / radiation characteristics in the infrared region. The outer surface of the first outer container (200) can receive solar radiation and increase its temperature, thereby reducing the temperature difference from the inside and lowering heat loss; even if the temperature rises, radiant heat loss from the inside is reduced through low emissivity.

[0030] Through the selective absorption / radiation coating surface, the first outer container (200) has the advantage of absorbing heat from the sun during the day and reducing heat radiated to the outside during the night, thereby reducing internal heat loss.

[0031] FIG. 3 is a second embodiment of the present invention. Referring to FIG. 3, an inner container (100) in which a high-temperature fluid is stored is contained within a first outer container (200), and the inner container (100) and the first outer container (200) are spaced apart to form a first insulation space (210). The second embodiment is characterized in that the first insulation space (210) is connected to a vacuum pump to form a vacuum, and a filler material (2), such as a solid filler material with a void formed to suppress it or a PCM (phase change material), is further disposed within the first insulation space (210). Heat loss occurs through the first outer container in contact with the outside (1), but the heat loss is reduced by placing a filler material (2), which has heat storage performance or stores heat energy emitted from the inner container (100), in the first insulation space (210).

[0032] A PCM (phase change material) is a material that absorbs and releases thermal energy during a phase change process. Through this, when the temperature rises, the PCM absorbs thermal energy, and when the temperature falls, the PCM releases thermal energy, which has the advantage of maintaining the temperature of the first insulation space (210). The PCM prevents the external surface temperature of the inner container (100) from changing rapidly.

[0033] Solid fillers include recycled aggregates produced by physically or chemically treating the byproducts of crushing waste concrete. Concrete is an example of recycled aggregate. Taking concrete as an example, it possesses high heat absorption and thermal emissivity. It is suitable for optimizing energy consumption by maintaining thermal stability in indoor and outdoor environments and regulating internal temperature.

[0034] The filler material (2) is formed in the form of pellets and is characterized by forming voids in the first insulation space. The filler material may be arranged in a single type or a mixture of multiple types in the first insulation space. For example, the interior of the first insulation space (210) may be composed of vacuum + recycled aggregate, vacuum + PCM, vacuum + recycled aggregate + PCM, etc. The reduction of heat loss can be optimized by optimizing the mixing ratio and filling rate of the filler material (2) in the first insulation space (210). For example, the first insulation space (210) may be filled with a filler material (2) in which recycled aggregate and PCM are mixed in a 2:1 ratio, covering 70% to 80% of the total volume of the first insulation space (210). The present invention does not numerically limit the mixing ratio and filling rate of the filling material (2), and can be modified by considering the spacing between the inner container (100) and the first outer container (200), and the materials of the inner container (100) and the outer container.

[0035] FIG. 4 is a third embodiment of the present invention. Referring to FIG. 4, the third embodiment includes an inner container (100) in which a high-temperature fluid is stored, a first outer container (200) that accommodates the inner container (100) to form a first insulating space (210), and a permeable body (300) spaced apart from the outer surface of the first outer container (200). An air layer (310) is formed between the first outer container (200) and the permeable body (300).

[0036] The first outer container (200) does not come into direct contact with the outside through the permeable body (300), thereby reducing heat loss due to convection. Additionally, an air layer (310) is formed between the first outer container (200) and the permeable body (300) to obtain an insulating effect. This has the advantage that the heat loss of the stored high-temperature fluid is reduced by the double insulating layer consisting of the first insulating space (210) and the air layer (310), and is less affected by rapid changes due to external temperature changes.

[0037] The width (W2) of the air layer (310), which is the spacing between the first outer container (200) and the permeable body (300), can be formed to be narrower than the width (W1) of the first insulation space (210), which is the spacing between the inner container (100) and the first outer container (200).

[0038] Sunlight passes through the transparent body (300) and is irradiated onto the outer surface of the first outer container (200). Through this, the first outer container (200) receives radiant heat from the sun and absorbs it, causing its temperature to rise. As the temperature of the first outer container (200) rises, the amount of heat radiated from the thermal energy of the first insulation space (210) to the air layer (310) is reduced. This has the effect of reducing heat loss in the first insulation space (210) and heat loss in the high-temperature fluid.

[0039] The first outer container (200) may have a coating surface placed on its outer surface to absorb more transmitted solar energy.

[0040] The features of the first, second, and third embodiments can be combined with each other. For example, a heat storage tank can be formed that includes the selective absorption coating surface of the first embodiment, the filler (2) of the second embodiment, and the permeable body (300) of the third embodiment. By combining the features of each embodiment, the heat loss effect can be increased.

[0041] FIG. 5 is another example of a heat storage tank. It is an example with the top and bottom omitted. A fluid inlet for fluid to flow into the heat storage tank, a fluid outlet for fluid to be discharged, and a vacuum pump for discharging internal gas are combined. Additionally, it is configured so that internal fluid does not leak out through a cover, etc. Referring to FIG. 5, the heat storage tank may be composed of multiple external containers to form multiple insulation spaces. The heat storage tank is composed of an internal container (100) in which a high-temperature fluid is stored, a first external container (200) that accommodates the internal container (100) and is spaced apart from the internal container (100) to form a first insulation space (210), and a second external container (400) that accommodates the first external container (200) and is spaced apart from the first external container (200) to form a second insulation space (410).

[0042] Multiple insulating spaces are formed to reduce heat loss of the fluid stored in the inner container (100). The inner container (100), the first outer container (200), the second outer container (400), ... may be composed of the Nth outer container. When multiple insulating spaces are formed to reduce heat loss, there is an advantage in that the heat loss of the fluid is reduced. However, problems arise such as increased costs for constructing the heat storage tank and increased space occupied by the heat storage tank. It is necessary to form multiple insulating spaces, but to improve the insulation effect by assigning characteristics to each insulating space according to the purpose, thereby reducing the cost for constructing the heat storage tank and reducing the space occupied.

[0043] FIG. 6 is an example of the application of the fourth embodiment. Referring to FIG. 6, the heat storage tank is composed of an inner container (100) in which a high-temperature fluid is stored, a first outer container (200) that accommodates the inner container (100) and is spaced apart from the inner container (100) to form a first insulation space (210), and a second outer container (400) that accommodates the first outer container (200) and is spaced apart from the first outer container (200) to form a second insulation space (410). The first insulation space (210) is formed as a vacuum and a filler material (2) is placed therein, and the second insulation space (410) is formed as a vacuum.

[0044] In the first insulation space (210), a filler material (2), such as recycled aggregate or PCM (phase change material), is further disposed. In the first insulation space (210), one or a mixture of multiple types of filler material (2) may be disposed. Depending on the required insulation performance, the mixing ratio and filling rate of the filler material (2) disposed in the first insulation space (210) can be adjusted to optimize the reduction of heat loss.

[0045] The first insulation space (210) and the second insulation space (410) are connected to a vacuum pump to discharge internal gas and form a vacuum state. By discharging internal gas, the loss caused by convective heat generated between the inner container (100) and the first outer container (200), and between the first outer container (200) and the second outer container (400) can be reduced.

[0046] The width of the first insulation space and the width of the second insulation space (410) may be formed to be the same or different depending on the purpose. Additionally, a filler material may be placed in the second insulation space. Multiple insulation spaces with filler materials can be formed to more effectively reduce heat loss. At this time, different types of filler materials may be placed. For example, a solid filler material with voids may be placed in the first insulation space to suppress the transfer of high-temperature heat emitted from the inner container to the outside, and a filler material made of PCM (phase change material) may be placed in the second insulation space to delay and buffer the transfer of temperature changes from the external environment to the first insulation space.

[0047] The fourth embodiment may be endowed with one or more features of the first, second, and third embodiments. The inner surfaces of the storage container, the first outer container (200), and the second outer container (400) may be endowed with low-emissivity surface characteristics through coating, painting, and surface treatment. This has the advantage of enabling stable fluid storage by reducing temperature fluctuations in the container.

[0048] Additionally, the permeable body (300) can be spaced apart from the outer surface of the outermost external container to form an air layer (310). By raising the temperature of the outermost external container through the permeable body (300) and the air layer (310), heat loss of the high-temperature fluid can be reduced.

[0049] The present invention is not limited to the embodiments described above, and its scope of application is diverse. Furthermore, it is understood that various modifications are possible without departing from the essence of the invention as claimed in the claims. Explanation of the symbols

[0050] 1 : External 2 : Filler 100 : Inner container 110 : Storage space 200 : 1st outer container 210: First insulation space 300 : Translucent 310 : Air layer 400 : Second outer container 410 : Second insulation space

Claims

Claim 1 An inner container having a storage space formed to store a high-temperature fluid; a first outer container formed to accommodate the inner container and spaced apart from the inner container; a second outer container formed to accommodate the first outer container and spaced apart from the first outer container; a first insulation space formed as a vacuum space between the inner container and the first outer container to reduce loss due to convective heat, and in which a solid filler with a void and a PCM (phase change material) are disposed to suppress the transfer of high-temperature heat emitted from the inner container to the outside; a second insulation space formed as a vacuum space between the first outer container and the second outer container to reduce loss due to convective heat, and in which a solid filler with a void and a PCM (phase change material) are disposed to delay and buffer the transfer of temperature changes of the external environment to the first insulation space; and the solid filler and PCM (phase change material) disposed in the first insulation space A high-insulation thermal storage tank characterized by having a different mixing ratio between the solid filler and the PCM (phase change material) placed in the second insulation space, and the inner container accommodating a fluid of 150°C or higher. Claim 2 A high-insulation thermal storage tank according to claim 1, comprising a coating surface having low emissivity disposed on the outer surface of the inner container or further comprising a coating surface having low emissivity disposed on the inner surface of the first outer container. Claim 3 delete Claim 4 A high-insulation thermal storage tank according to claim 1, wherein the outer surface of the first outer container further comprises a selective absorption coating surface having a high absorption rate and emissivity in the visible light region and a low absorption rate and emissivity in the infrared region to absorb solar radiation. Claim 5 A high-insulation thermal storage tank according to claim 1, comprising a transparent body made of a material that transmits sunlight and is spaced apart from the outer surface of the first outer container, and an air layer formed between the first outer container and the transparent body. Claim 6 delete Claim 7 A high-insulation thermal storage tank according to claim 1, further comprising a transparent body made of a material that transmits sunlight and is spaced apart from the outer surface of the second outer container, and an air layer formed between the second outer container and the transparent body. Claim 8 A high-insulation thermal storage tank according to claim 1, comprising a selective absorption coating surface disposed on the outer surface of the second outer container, having high absorption and emissivity in the visible light region and low absorption and emissivity in the infrared region. Claim 9 delete Claim 10 delete

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