Adsorption bed and its heat transfer means

Abstract

This invention discloses an adsorption component for an adsorption bed, including a heat exchange channel wall for forming a heat exchange channel. A composite adsorbent layer is disposed on the side of the heat exchange channel wall away from the heat exchange channel. The composite adsorbent layer comprises a mixture of adsorbent particles and thermally conductive particles, wherein the thermal conductivity of the thermally conductive particles is higher than that of the adsorbent particles. By incorporating the thermally conductive particle adsorbent layer, better heat transfer can be achieved with the heat exchange channel wall in the direction away from the heat exchange channel wall, i.e., the direction of heat transfer. Therefore, this adsorption component for an adsorption bed can effectively solve the problem of poor heat transfer performance of current adsorbent layers. This invention also discloses an adsorption bed including the above-described heat transfer component.

Description

Technical Field

[0001] This invention relates to the field of adsorption technology, and more specifically, to a heat transfer component for an adsorption bed, and to an adsorption bed including the aforementioned heat transfer component. Background Technology

[0002] At low temperatures, the adsorbent in an adsorption bed can adsorb or / and bind to gaseous adsorbates. This can be a physical change, such as the gaseous working fluid changing into a liquid state to be adsorbed onto the adsorbent; or a chemical change, where the adsorbate chemically binds to the adsorbent, resulting in the adsorption of the adsorbate. At high temperatures, the adsorbent can absorb heat to generate gaseous adsorbates, which are then released. This process is the reverse of the above; it can be a change from liquid to gas or a chemical change to release the gaseous working fluid.

[0003] During the desorption and / or adsorption stages, a heat exchange fluid is required to exchange heat with the adsorbent in the adsorption chamber. Therefore, an adsorption chamber is formed within the adsorption bed, with heat transfer channels extending through it. The fluid in these channels can transfer heat with the adsorbent in the adsorption chamber. Simultaneously, a mass transfer cavity is also provided within the adsorption chamber to allow the gaseous adsorbent to flow through it. During the adsorption stage, the gaseous adsorbent formed in the evaporator is transported to the mass transfer cavity, where it contacts and is received by the adsorbent. During the desorption stage, the adsorbent desorbs the gaseous adsorbent, which enters the mass transfer cavity and then exits the condenser from the outlet of the mass transfer cavity.

[0004] In the process of realizing this invention, the inventors discovered that the prior art has at least the following problems: the adsorbent needs to exchange heat with the heat exchange channel, while the adsorption working fluid needs to be combined with the adsorbent. How to efficiently transfer mass and heat has become an urgent problem for adsorption beds. Summary of the Invention

[0005] In view of this, the first objective of the present invention is to provide a heat transfer component for an adsorption bed that can effectively solve the problem of poor heat transfer performance of current heat transfer components. The second objective of the present invention is to provide an adsorption bed including the above-mentioned heat transfer component.

[0006] To achieve the first objective mentioned above, the present invention provides the following technical solution: An adsorption component for an adsorption bed includes a heat exchange channel wall for forming a heat exchange channel. The heat exchange channel wall has a composite adsorbent layer disposed on a side away from the heat exchange channel. The composite adsorbent layer includes a mixture of adsorbent particles and thermally conductive particles, wherein the thermal conductivity of the thermally conductive particles is higher than that of the adsorbent particles.

[0007] In the adsorption components of the aforementioned adsorption bed, a composite adsorbent layer is used in the adsorbent layer during use. This composite adsorbent layer incorporates thermally conductive particles with higher thermal conductivity, thereby improving heat transfer efficiency in the heat transfer direction. Simultaneously, it reduces the adsorbent content and lowers the mass transfer pressure. This allows the adsorbent layer, by incorporating thermally conductive particles, to achieve better heat transfer in the direction away from the heat exchange channel wall, i.e., the direction of heat transfer. In summary, the adsorption components of this adsorption bed effectively solve the problem of poor heat transfer performance in current adsorbent layers.

[0008] In some technical solutions, the outer wall of the heat exchange channel wall has an extension extending away from the heat exchange channel wall; the composite adsorbent layer is attached to the extension.

[0009] In some technical solutions, the thickness of the composite adsorbent layer attached to the epitaxial portion gradually decreases along the direction away from the wall of the heat exchange channel.

[0010] In some technical solutions, the volume ratio of the thermally conductive particles in the composite adsorbent layer attached to the epitaxial portion gradually decreases along the direction away from the wall of the heat exchange channel.

[0011] In some technical solutions, the heat-conducting particles are rod-shaped.

[0012] In some technical solutions, the thermally conductive particles are rod-shaped along the thickness direction and arranged in a chain.

[0013] In some technical solutions, at least a portion of the thermally conductive particles have a larger volume than the adsorbent particles.

[0014] In some technical solutions, at least a portion of the thermally conductive particles have a smaller volume than the adsorbent particles.

[0015] In some technical solutions, along the thickness direction, the composite adsorbent layer includes an inner layer and an outer layer, the inner layer is located on the side of the outer layer that is closer to the heat exchange channel wall, and the content of thermally conductive particles in the inner layer is greater than the content of thermally conductive particles in the outer layer.

[0016] To achieve the second objective mentioned above, the present invention also provides an adsorption bed, which includes any of the aforementioned heat transfer components and a chamber, wherein the heat transfer component is disposed in the chamber. Since the aforementioned heat transfer components possess the above-mentioned technical effects, the adsorption bed having such heat transfer components should also possess corresponding technical effects. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the adsorption component of the adsorption bed provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of an adsorption component for another adsorption bed provided in an embodiment of the present invention.

[0019] The following labels are shown in the attached diagram: 1. Heat exchange tube; 2. Composite adsorbent layer; 3. Heat exchange fluid; 4. Mass transfer chamber; Heat exchange channel wall 11, heat exchange channel 12, extension 13; Outer layer 21, inner layer 22. Detailed Implementation

[0020] This invention discloses a heat transfer component for an adsorption bed, which can effectively solve the problem of poor heat transfer performance of current heat transfer components.

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1-2 , Figure 1 This is a schematic diagram of the adsorption component of the adsorption bed provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of an adsorption component for another adsorption bed provided in an embodiment of the present invention.

[0023] In some embodiments, this embodiment provides an adsorption component for an adsorption bed. Specifically, the adsorption component mainly includes a heat exchange channel wall 11 and an adsorbent layer. The adsorption bed is primarily the adsorption bed of an adsorption refrigeration system.

[0024] The heat exchange channel wall 11 forms the heat exchange channel 12, which can be a parallel channel or a tubular channel. Therefore, the heat exchange channel wall 11 can be the wall of the heat exchange tube 1 or a partition structure. One side of the heat exchange channel wall 11 faces the heat exchange channel 12, and the other side faces the mass transfer chamber 4. The heat exchange channel 12 is used for the flow of the heat exchange fluid 3, while the mass transfer chamber 4 is used for the flow of the gaseous adsorbent working fluid that cooperates with the adsorbent.

[0025] When a high-temperature fluid, namely the desorption heat exchange fluid 3, flows in the heat exchange channel 12, the high-temperature fluid heats the adsorbent so that the adsorbent desorbs the gaseous adsorbent working medium, and the gaseous adsorbent working medium enters the mass transfer chamber 4, and then flows out of the mass transfer chamber 4 and into the connected condenser.

[0026] When a low-temperature fluid, namely the adsorption heat exchange fluid 3, flows in the heat exchange channel 12, the low-temperature fluid absorbs heat from the adsorbent so that the adsorbent can adsorb the gaseous adsorbent in the mass transfer chamber 4. At this time, the mass transfer chamber 4 will form a negative pressure to adsorb the gaseous adsorbent in the evaporator, so that the gaseous adsorbent will continue to evaporate in the evaporator.

[0027] Specifically, at least a portion of the adsorbent forms an adsorbent layer, which is disposed on the side of the heat exchange channel wall 11 away from the heat exchange channel 12, thus separating it from the heat exchange channel 12. The adsorbent layer adheres to the surface of the heat exchange channel wall 11 and is in heat transfer contact with the heat exchange channel wall 11.

[0028] The adsorbent layer contains adsorbents, which form adsorption-working-medium pairs with the working medium. One working medium can correspond to multiple adsorbent materials; therefore, the adsorbent layer can include multiple adsorbent materials, such as aluminum phosphate and silica gel. The adsorbent and working medium can form physical adsorption-working-medium pairs or chemical adsorption-working-medium pairs. For example, when the mass transfer chamber 4 includes multiple working media, the adsorbent layer can include both physical and chemical adsorbents. Considering that some chemical adsorption can alter the physical properties of the adsorbent, leading to reduced fixation, the use of such chemical adsorbents can be avoided when maintaining physical properties is required.

[0029] The adsorbent layer can be a composite adsorbent layer 2, which includes not only the adsorbent but also a thermally conductive material with a high thermal conductivity, wherein the thermal conductivity of the thermally conductive material is higher than that of the adsorbent. Specifically, the composite adsorbent layer can include a mixture of adsorbent particles and thermally conductive particles, wherein the thermal conductivity of the thermally conductive particles is higher than that of the adsorbent particles. The thermally conductive particles, such as metal particles, are used, and particles with higher thermal conductivity are employed to improve heat transfer between the adsorbent particles, thereby enhancing thermal conductivity.

[0030] The thermally conductive particles and adsorbent particles can be the same size or different. Generally, the volume of the metal particles can be larger than that of the adsorbent particles, such as the former being 3 to 10 times larger than the latter, to reduce the number of metal particles and ensure continuity between them. It should be noted that since the mixed adsorbent layer contains a large number of adsorbent particles, and the sizes of these particles are not necessarily identical, the volume of the adsorbent particles in the composite adsorbent layer 2 can be either the average volume or the volume of adsorbent particles of intermediate size. Similarly, the mixed adsorbent layer also contains a large number of thermally conductive particles, which may also vary in size. Therefore, the volume of the thermally conductive particles in the composite adsorbent layer 2 can also be either the average volume or the volume of thermally conductive particles of intermediate size.

[0031] The thermally conductive particles and adsorbent particles can be either scattered or adhered together. They can be powdered or larger gravel-like particles. Generally, in manufacturing the adsorbent layer, the powdered thermally conductive particles and powdered adsorbent particles are mixed into a slurry, which is then applied to the heat exchange channel wall 11 using spraying, dipping, or other methods, and then allowed to cure.

[0032] In the adsorption component of the aforementioned adsorption bed, a composite adsorbent layer 2 is used in the adsorbent layer during use. This composite adsorbent layer 2 incorporates thermally conductive particles with higher thermal conductivity, thereby improving heat transfer efficiency in the heat transfer direction. Simultaneously, it reduces the adsorbent content and lowers the mass transfer pressure. This allows the adsorbent layer to achieve better heat transfer with the heat exchange channel wall 11 in the direction away from the heat exchange channel wall 11, i.e., the direction of heat transfer. In summary, the adsorption component of this adsorption bed effectively solves the problem of poor heat transfer performance in current adsorbent layers.

[0033] In some embodiments, the material of the heat-conducting particles and the material of the heat exchange channel wall 11 can be the same, such as both being the same metal material, such as both being copper or both being aluminum, to further reduce the thermal resistance between them. Of course, the materials of the heat-conducting particles and the heat exchange channel wall 11 can also be different, and can be set according to specific needs.

[0034] In some embodiments, considering the increased thermal conductivity, the heat transfer area is generally larger. To further improve the thermal conductivity, it is preferable that the outer wall of the heat exchange channel wall 11 has an extension 13 extending away from the heat exchange channel wall 11. The extension 13 extends entirely away from the heat exchange channel wall 11, and may be branched or not branched in the extension direction. The extension 13 is also a high-efficiency heat transfer part, and its heat transfer coefficient is generally higher than that of the adsorbent particles. The extension 13 and the heat transfer channel wall should be thermally connected and fixedly connected, so that the extension 13 can be supported by the heat transfer channel wall. The extension 13 and the heat transfer channel wall can be integrally formed or welded, and both are preferred.

[0035] The extension portion 13 can be as shown in the attached figure. Figure 1 The fin structure shown can be configured such that, in order to achieve better temperature drop or temperature rise in the direction of fluid flow in the heat exchange channel 12, the thickness direction of the fin structure intersects with the direction of fluid flow in the heat exchange channel 12, such as being perpendicular, to slow down heat transfer in that direction. The fin structure can be a threaded fin structure. If the heat exchange channel wall 11 is a pipe wall, the fin structure can be annular fins, in which case the direction of fluid flow in the heat exchange channel 12 is consistent with the pipe extension direction.

[0036] The extension 13 can also be as shown in the attached figure. Figure 2 The branch-shaped structure shown can be a topological structure, that is, a growth structure formed in the direction away from the heat transfer channel wall to facilitate heat transfer.

[0037] The outer portion 13 is attached with a composite adsorbent layer 2 to increase the heat transfer area and improve the heat transfer effect. When entering the desorption stage, the high-temperature fluid, i.e., the heat exchange fluid 3 for desorption, transfers heat to the heat exchange channel wall 11, and then from the heat exchange channel wall to the outer portion 13. Along the direction away from the heat transfer channel wall, the outer portion 13 gradually transfers heat to the composite adsorbent layer 2 to heat the adsorbent in the composite adsorbent layer 2, so as to desorb the gaseous adsorbent working fluid.

[0038] When entering the adsorption stage, the low-temperature fluid, i.e. the heat exchange fluid 3 for adsorption, is used. When the gaseous adsorbent is adsorbed by the adsorbent, the heat generated is transferred to the epitaxial part 13. Then, the heat of the adsorbent gradually gathers in the epitaxial part 13 towards the wall of the heat transfer channel, and is then transferred to the wall of the heat transfer channel and then to the heat exchange fluid 3.

[0039] The extension of the extension portion 13 can better increase the heat exchange area and improve the heat transfer effect. At the same time, the increased heat exchange area is beneficial for mass transfer.

[0040] In some embodiments, considering that the epitaxial portion 13 experiences a temperature drop during the desorption phase along the direction away from the heat transfer channel wall, the temperature drive effect gradually decreases in the direction away from the heat transfer channel wall. Therefore, it is preferable that the thickness of the adsorbent layer attached to the epitaxial portion 13 gradually decreases along the direction away from the heat exchange channel wall 11, so that heat transfer is concentrated at the root, while heat transfer at the top is relatively small.

[0041] As attached Figure 1 As shown, the thickness of the composite adsorbent layer 2 attached to the epitaxial portion 13 gradually decreases from one end to the other. Moreover, the thicker end is not only attached to the root of the epitaxial portion 13, but also to the heat exchange channel wall 11, further enhancing the heat transfer effect of the thicker part.

[0042] In some instances, considering that the heat transfer path of the adsorbent layer at the root is relatively large and more dependent on the heat transfer effect, the volume ratio of the heat-conducting particles in the adsorbent layer attached to the extension portion 13 can gradually decrease along the direction away from the heat exchange channel wall 11.

[0043] In some embodiments, the thermally conductive particles can be spherical, as spherical shapes are generally easier to manufacture. Of course, the thermally conductive particles can also be in the form of sheets, but sheet-like particles may affect mass transfer efficiency, although they can improve heat transfer efficiency and reduce contact thermal resistance.

[0044] To improve mass and heat transfer, the thermally conductive particles can be rod-shaped. Because of their longer extension, these rod-shaped structures allow different particles to easily come into contact with each other, but because of their rod shape, they do not affect mass transfer. Mass transfer refers to the transfer of the gaseous adsorbent working fluid within the composite adsorbent layer 2.

[0045] In some embodiments, the thermally conductive particles can be rod-shaped and extend along the thickness direction in a chain-like arrangement. This chain-like arrangement can be achieved using a magnetic field. This ensures better heat transfer along the thickness direction while minimizing the impact on mass transfer in the thickness direction.

[0046] In some embodiments, as described above, for better heat and mass transfer, it is preferable that the volume of the thermally conductive particles is larger than the volume of the adsorbent particles.

[0047] In some embodiments, on the other hand, to facilitate heat transfer between adsorbent particles, the volume of the thermally conductive particles can be smaller than that of the adsorbent particles. This is because one cause of contact thermal resistance is the air gap layer present in the contact between two solid surfaces, and the small-particle structure of the thermally conductive particles (with a particle size smaller than that of the adsorbent particles) filling the gaps between the adsorbent particles can reduce the contact thermal resistance.

[0048] Of course, in some embodiments, two parts of heat-conducting particles can be provided: one part of the heat-conducting particles has a volume larger than the adsorbent particles, such as the volume of this part of the heat-conducting particles is preferably between 2 and 6 times the volume of the adsorbent particles, so as to better transfer the heat on the heat transfer channel wall to the adsorbent particles; while the other part of the heat-conducting particles has a volume smaller than the adsorbent particles, such as the volume of this part of the heat-conducting particles is preferably between 0.1 and 0.6 times the volume of the adsorbent particles, so as to better fill the spaces between the adsorbent particles to facilitate heat transfer between the adsorbent particles.

[0049] In some embodiments, the composite adsorbent layer 2 may include an inner layer 22 and an outer layer 21 along the thickness direction. The inner layer 22 is located on the side of the outer layer 21 facing the wall of the heat exchange channel 12. The content of thermally conductive particles in the inner layer 22 is greater than that in the outer layer 21. The content of thermally conductive particles can be the percentage of thermally conductive particles per unit volume of the composite adsorbent layer 2, which can be obtained by density and weight measurements. A higher percentage of thermally conductive particles in the inner layer 22 results in improved thermal conductivity and lower mass transfer; while a lower percentage of thermally conductive particles in the outer layer 21 results in poor thermal conductivity and higher mass transfer. The inner layer 22 itself also needs to transfer heat between the outer layer 21 and the wall of the heat exchange channel, so improved thermal conductivity facilitates heat transfer between the outer layer 21 and the wall of the heat exchange channel; however, the mass transfer of the inner layer 22 needs to pass through the outer layer 21, so the mass transfer pressure is high. Therefore, reducing the mass transfer requirement can reduce the mass transfer pressure. On the other hand, the outer layer 21 also needs to transfer mass between the inner layer 22 and the external mass transfer channel. Therefore, the mass transfer pressure of the outer layer 21 is small, and more adsorbed working fluid can be directly transferred to the external mass transfer channel. Moreover, the outer layer 21 does not need to transfer heat, so the thermal conductivity requirement of the outer layer 21 is not high.

[0050] Specifically, the volume percentage of thermally conductive particles in the inner layer 22 can be between 0.2 and 0.3, while the volume percentage of thermally conductive particles in the inner layer 22 can be between 0 and 0.1. It should be noted that the composite adsorbent layer 2 can include a greater thickness along the thickness direction.

[0051] Based on the heat transfer components provided in the above embodiments, the present invention also provides an adsorption bed, which includes any one of the heat transfer components in the above embodiments, including a chamber, wherein the heat transfer component is disposed in the chamber. Since this adsorption bed uses the heat transfer components in the above embodiments, the beneficial effects of this adsorption bed are explained in the above embodiments.

[0052] Furthermore, the adsorption bed can be equipped with multiple heat transfer components as modular parts, evenly arranged in the adsorption bed chamber. In this case, each heat transfer component has a multi-port structure at both ends of its heat pipe 1, serving as a collector and a distributor, respectively.

[0053] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0054] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An adsorption component for an adsorption bed, comprising a heat exchange channel wall (11) for forming a heat exchange channel (12), characterized in that, The heat exchange channel wall (11) is provided with a composite adsorbent layer (2) on the side away from the heat exchange channel (12). The composite adsorbent layer (2) includes a mixture of adsorbent particles and thermally conductive particles. The thermal conductivity of the thermally conductive particles is higher than that of the adsorbent particles.

2. The adsorption component of the adsorption bed according to claim 1, characterized in that, The outer wall of the heat exchange channel wall (11) has an extension (13) extending away from the heat exchange channel wall (11); the composite adsorbent layer (2) is attached to the extension (13).

3. The adsorption component of the adsorption bed according to claim 2, characterized in that, Along the direction away from the heat exchange channel wall (11), the thickness of the composite adsorbent layer (2) attached to the extension portion (13) gradually decreases.

4. The adsorption component of the adsorption bed according to claim 2 or 3, characterized in that, Along the direction away from the heat exchange channel wall (11), the volume ratio of the thermally conductive particles in the composite adsorbent layer (2) to which the extension portion (13) is attached gradually decreases.

5. The adsorption component of the adsorption bed according to claim 1, characterized in that, The heat-conducting particles are rod-shaped.

6. The adsorption component of the adsorption bed according to claim 1, characterized in that, The thermally conductive particles are rod-shaped along the thickness direction and arranged in a chain.

7. The adsorption component of the adsorption bed according to claim 1, characterized in that, At least a portion of the thermally conductive particles have a volume larger than the adsorbent particles.

8. The adsorption component of the adsorption bed according to claim 1, characterized in that, At least a portion of the thermally conductive particles have a smaller volume than the adsorbent particles.

9. The adsorption component of the adsorption bed according to claim 1, characterized in that, Along the thickness direction, the composite adsorbent layer (2) includes an inner layer (22) and an outer layer (21). The inner layer (22) is located on the side of the outer layer (21) that is close to the wall of the heat exchange channel (12). The content of thermally conductive particles in the inner layer (22) is greater than the content of thermally conductive particles in the outer layer (21).

10. An adsorption bed, comprising a chamber, characterized in that, It also includes the heat transfer member as described in any one of claims 1-9, wherein the heat transfer member is disposed in the chamber.

Images