Axial and radial mixed flow large-scale cold storage packed bed and method

Abstract

The invention belongs to the technical field of cold energy storage, liquid air energy storage and the like, and particularly relates to an axial and radial mixed flow large-scale cold storage packed bed and a method, the axial and radial mixed flow large-scale cold storage packed bed comprises a bottom port, an axial flow area, a large-particle-size cold storage material, an internal channel, a radial flow area, a small-particle-size energy storage material, an annular channel, a top port and a thermal insulation material. Low-temperature fluid flows in from the bottom, flows through the axial flow area and the radial flow area and then flows out from the top. By means of shaft-diameter combination and particle size change, the flow uniformity is improved, the pressure drop and the pumping work loss are effectively reduced, meanwhile, the cold insulation mode of different partitions is adopted, development of a thermocline is weakened, and then the overall efficiency is improved. In addition, due to the radial flow characteristic, namely small vertical height, multi-layer stacking can be realized, so that the occupied area is reduced, and the integration level of the bed body is improved.

Description

Technical Field

[0001] The present invention belongs to the technical fields of cold energy storage, liquid air energy storage, etc., and particularly relates to an axial and radial mixed-flow large-scale cold storage packed bed and method. Background Art

[0002] At present, all sectors of society highly focus on how to reduce the dependence on fossil energy and accelerate the transformation to renewable energy such as wind energy and solar energy. However, renewable energy has inherent defects such as large output fluctuations, strong intermittency, and obvious seasonality, resulting in a large amount of green electricity being forced to be abandoned because it cannot be consumed in real time, which has become the main bottleneck restricting its large-scale development. As an important regulation means, the cold storage technology can effectively suppress the volatility and intermittency problems of renewable energy and shows broad application prospects.

[0003] The cold storage packed bed is a common cold storage device, which plays an important role in the liquid air energy storage system. During the cold storage and cold release processes of the system, due to the large fluid flow rate, the flow loss caused by the pressure drop of the packed bed is large, affecting the system efficiency. In addition, since the traditional packed bed has an axial flow structure and cannot effectively utilize the vertical space, the floor area is large, thus affecting the integration. And due to the existence of the thermocline, the cold energy loss caused by the mixing of different grades of energy is large. Therefore, there is an urgent need to develop a new type of cold storage packed bed with low flow loss, small floor area, and low energy self-dissipation. Summary of the Invention

[0004] Based on the above deficiencies of the prior art, the technical problem to be solved by the present invention is to provide an axial and radial mixed-flow large-scale cold storage packed bed and method, which can effectively reduce the flow loss caused by the pressure drop, reduce the floor area and the mixing of different grades of energy, and improve the cold storage efficiency and applicability of the packed bed.

[0005] To achieve the above object, the present invention adopts the following technical solutions: An axial and radial mixed-flow large-scale cold storage packed bed, comprising a bed body, and the bed body includes: Ports, which are divided into bottom ports and top ports. The bottom ports are arranged at the bottom of the bed body, and the top ports are arranged at the top of the bed body; Channels, which include internal channels and annular channels. The internal channels are arranged at the middle position of the bed body, and the annular channels are arranged outside the internal channels; Flow regions, which are divided into an axial flow region and a radial flow region. The axial flow region is arranged at the lower end of the bed body, and the radial flow region is arranged at the upper end of the bed body; and the radial flow region is arranged between the internal channels and the annular channels; Energy storage materials, which include large-particle-size cold storage materials and small-particle-size cold storage materials; A grille, the grille including a bottom grille, a radial flow inlet grille, a radial flow outlet grille, a first vertical grid, a second vertical grid, a third vertical grid, a fourth vertical grid, and a fifth vertical grid; A heat insulation material, the heat insulation material being disposed outside the bed body.

[0006] Further, the internal channel includes a first internal channel, a second internal channel, and a third internal channel, and the third internal channel, the second internal channel, and the first internal channel are arranged in sequence from top to bottom; the annular channel includes a first annular channel and a second annular channel; the second annular channel is disposed above the first annular channel; the first internal channel, the second internal channel, and the third internal channel are disposed inside the radial flow region, the first annular channel and the second annular channel are disposed outside the radial flow region, and the first annular channel and the second annular channel circumferentially wrap the radial flow region.

[0007] Further, the radial flow region includes a first radial flow region, a second radial flow region, a third radial flow region, and a fourth radial flow region; the fourth radial flow region, the third radial flow region, the second radial flow region, and the first radial flow region are arranged in sequence from top to bottom.

[0008] Further, the large-particle-size cold storage material is disposed in the axial flow region, and the small-particle-size cold storage material is disposed in the radial flow region.

[0009] Further, the heat insulation material is pearlite or vitrified microsphere material.

[0010] Further, the bottom grille is disposed between the bottom port and the axial flow region, the radial flow inlet grille is disposed between the axial flow region and the radial flow region, the radial flow outlet grille is disposed between the radial flow region and the top port, the first vertical grid is disposed between the first internal channel and the first radial flow region, the second vertical grid is disposed between the first radial flow region and the first annular channel, the third vertical grid is disposed between the second internal channel and the second radial flow region, the fourth vertical grid is disposed between the third radial flow region and the second annular channel, and the fifth vertical grid is disposed between the third internal channel and the fourth radial flow region.

[0011] The present invention also provides a cold storage method for an axial and radial hybrid flow large-scale cold storage packed bed, including a cold storage process and a cold release process: Cold storage process: The low-temperature fluid flows in from the bottom port, enters the axial flow area after passing through the bottom grid. The low-temperature fluid releases cold energy and stores it in the large-particle-size cold storage material. Then it flows into the first internal channel through the radial flow inlet grid, and then the fluid enters the first radial flow area through the first vertical grid. The low-temperature fluid exchanges cold with the small-particle-size cold storage material and stores it in the small-particle-size cold storage material. Then it flows into the first annular channel through the second vertical grid, and then into the second radial flow area through the second vertical grid for cold energy exchange. Then it flows into the second internal channel through the third vertical grid, and then into the third radial flow area through the third vertical grid for cold energy exchange. Then it flows into the second annular channel through the fourth vertical grid, and then into the fourth radial flow area through the fourth vertical grid for cold energy exchange. Then it flows into the third internal channel through the fifth vertical grid and finally flows out of the top port through the radial flow outlet grid to complete the cold storage process; Cold release process: The normal-temperature fluid flows in from the top port, enters the third internal channel through the radial flow outlet grid. Then it enters the fourth radial flow area through the fifth vertical grid, exchanges cold energy with the small-particle-size cold storage material and absorbs the stored cold. The fluid then flows into the second annular channel through the fourth vertical grid and enters the third radial flow area through the fourth vertical grid for cold exchange. Then the fluid flows into the second internal channel through the third vertical grid and enters the second radial flow area through the third vertical grid to absorb the cold in the cold storage material. After that, the normal-temperature fluid flows into the first annular channel through the second vertical grid and enters the first radial flow area through the second vertical grid for cold exchange. The fluid then enters the first internal channel through the first vertical grid and enters the axial flow area through the radial flow inlet grid, where it absorbs the cold energy of the large-particle-size cold storage material. Finally, the fluid flows out of the bottom port through the bottom grid to complete the cold release process.

[0012] Furthermore, the bottom of the bed body is the axial flow area, and the top of the bed body is the radial flow area, which is used to reduce the pressure drop change caused by the volume expansion of the fluid.

[0013] Furthermore, the small-particle-size cold storage material used in the radial flow area can enhance heat transfer while improving the flow uniformity.

[0014] Furthermore, the combination of the axial flow area and the radial flow area can reduce the floor area and improve the utilization rate of the vertical space in large-scale applications.

[0015] By adopting the above technical solutions: The present invention reduces the pressure drop and pump work loss caused by fluid flow through the combination of radial flow and axial flow; and because the vertical height of the radial flow is small, it can be stacked in multiple layers to reduce the floor area, thereby improving the integration degree of the bed body; at the same time, different partitions are carried out to reduce the energy mixing.

[0016] As described above, compared with the prior art, the present invention has the following beneficial effects: 1. The present invention utilizes the property of small pressure drop in the radial flow region, which can effectively cope with the volume expansion caused by the temperature rise after fluid flow heat transfer, thereby reducing the flow loss.

[0017] 2. The present invention utilizes the characteristics of radial flow, reduces the floor area, improves the space utilization rate, and enhances the system integration degree.

[0018] 3. The present invention divides the axial flow and radial flow into different regions, and further divides the internal part of the radial flow into different regions, reducing the contact area between high-grade cold energy and low-grade cold energy, and reducing the energy loss during the cold storage stage.

[0019] The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly, it can be implemented according to the content of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and understandable, the following is a detailed description in conjunction with the preferred embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly introduced below.

[0021] Figure 1 FIG. is a schematic structural diagram of a hybrid flow large-scale cold storage packed bed according to Embodiment 1 of the invention.

[0022] In the figure: 1. Bottom port; 2. Bottom grid; 3. Axial flow region; 4. Large particle size cold storage material; 5. Radial flow inlet grid; 6. First internal channel; 7. First vertical grid; 8. Small particle size cold storage material; 901. First radial flow region; 902. Second radial flow region; 903. Third radial flow region; 904. Fourth radial flow region; 10. Second vertical grid; 11. Annular channel; 12. Third vertical grid; 13. Second internal channel; 14. Fourth vertical grid; 15. Second annular channel; 16. Fifth vertical grid; 17. Third internal channel; 18. Radial flow outlet grid; 19. Top port; 20. Thermal insulation material. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the scope of protection of the present invention.

[0024] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] As Figure 1 shown, an axially and radially mixed-flow large-scale cold storage packed bed includes a bed body, and the bed body includes: Ports, which are divided into a bottom port 1 and a top port 19. The bottom port 1 is arranged at the bottom of the bed body, and the top port 19 is arranged at the top of the bed body; Channels, which include an internal channel and an annular channel. The internal channel is arranged at the middle position of the bed body, and the annular channel is arranged outside the internal channel; Flow regions, which are divided into an axial flow region 3 and a radial flow region. The axial flow region 3 is arranged at the lower end of the bed body, and the radial flow region is arranged at the upper end of the bed body; and the radial flow region is arranged between the internal channel and the annular channel; Energy storage materials, which include large-particle-size cold storage materials 4 and small-particle-size cold storage materials 8; Grids, which include a bottom grid 2, a radial flow inlet grid 5, a radial flow outlet grid 18, a first vertical grid 7, a second vertical grid 10, a third vertical grid 12, a fourth vertical grid 14, and a fifth vertical grid 16; Thermal insulation material 20, which is arranged outside the bed body.

[0026] Specifically, the internal channel includes a first internal channel 6, a second internal channel 13, and a third internal channel 17. The third internal channel 17, the second internal channel 13, and the first internal channel 6 are arranged in sequence from top to bottom; the annular channel includes a first annular channel 11 and a second annular channel 15; the second annular channel 15 is arranged above the first annular channel 11; the first internal channel 6, the second internal channel 13, and the third internal channel 17 are arranged inside the radial flow region, and the first annular channel 11 and the second annular channel 15 are arranged outside the radial flow region, and the first annular channel 11 and the second annular channel 15 circumferentially wrap the radial flow region.

[0027] Specifically, the radial flow region includes a first radial flow region 901, a second radial flow region 902, a third radial flow region 903, and a fourth radial flow region 904; the fourth radial flow region 904, the third radial flow region 903, the second radial flow region 902, and the first radial flow region 901 are arranged in sequence from top to bottom.

[0028] Specifically, the large-particle-size cold storage material 4 is arranged in the axial flow region 3, and the small-particle-size cold storage material 8 is arranged in the radial flow region.

[0029] Specifically, the thermal insulation material 20 is pearlite or vitrified microsphere material.

[0030] Specifically, the bottom grid 2 is arranged between the bottom port 1 and the axial flow region 3, the radial flow inlet grid 5 is arranged between the axial flow region 3 and the radial flow region, the radial flow outlet grid 18 is arranged between the radial flow region and the top port 19, the first vertical grid 7 is arranged between the first internal channel 6 and the first radial flow region 901, the second vertical grid 10 is arranged between the first radial flow region 901 and the first annular channel 11, the third vertical grid 12 is arranged between the second internal channel 13 and the second radial flow region 902, the fourth vertical grid 14 is arranged between the third radial flow region 903 and the second annular channel 15, and the fifth vertical grid 16 is arranged between the third internal channel 17 and the fourth radial flow region 904.

[0031] In this embodiment, the energy loss caused by fluid flow can be reduced by combining radial flow and axial flow, thereby reducing the pump work loss. Since the vertical height of the radial flow is small, multiple layers can be stacked to reduce the floor area, thereby improving the integration degree of the bed body. At the same time, different partitions are made for the entire bed body, reducing energy mixing and achieving efficient cold storage.

[0032] In another embodiment of the present invention, a method for large-scale cold storage with axial and radial mixed flow is provided, and this method is realized based on the mixed-flow large-scale cold storage packed bed in the above embodiment. Specifically, this method includes the following steps: Cold storage process: The low-temperature fluid flows in from the bottom port 1, enters the axial flow region 3 after passing through the bottom grid 2. The low-temperature fluid releases cold energy and stores it in the large-particle-size cold storage material 4. Then it flows into the first internal channel 6 through the radial flow inlet grid 5. Subsequently, the fluid enters the first radial flow region 901 via the first vertical grid 7. The low-temperature fluid exchanges cold with the small-particle-size cold storage material 8 and stores the cold in the small-particle-size cold storage material 8. Then it flows into the first annular channel 11 via the second vertical grid 10, and then into the second radial flow region 902 via the second vertical grid 10 for cold energy exchange. Then it flows into the second internal channel 13 through the third vertical grid 12, and then into the third radial flow region 903 through the third vertical grid 12 for cold energy exchange. Then it flows into the second annular channel 15 through the fourth vertical grid 14, and then into the fourth radial flow region 904 via the fourth vertical grid 14 for cold energy exchange. Then it flows into the third internal channel 17 via the fifth vertical grid 16, and finally flows out of the top port 19 through the radial flow outlet grid 18, completing the cold storage process; Cold release process: The normal-temperature fluid flows in from the top port 19, enters the third internal channel 17 through the radial flow outlet grid 18. Subsequently, it enters the fourth radial flow region 904 through the fifth vertical grid 16, exchanges cold with the small-particle-size cold storage material 8 and absorbs the stored cold. The fluid then flows into the second annular channel 15 via the fourth vertical grid 14, and then enters the third radial flow region 903 through the fourth vertical grid 14 for cold energy exchange. Subsequently, the fluid flows into the second internal channel 13 through the third vertical grid 12, and enters the second radial flow region 902 through the third vertical grid 12 to absorb the cold in the cold storage material. After that, the normal-temperature fluid flows into the first annular channel 11 via the second vertical grid 10, and then enters the first radial flow region 901 through the second vertical grid 10 for cold energy exchange. The fluid then enters the first internal channel 6 through the first vertical grid 7, and enters the axial flow region 3 through the radial flow inlet grid 5, where it absorbs the cold energy of the large-particle-size cold storage material 4. Finally, the fluid flows out of the bottom port 1 through the bottom grid 2, completing the cold release process.

[0033] Specifically, the bottom of the bed body is the axial flow region 3, and the top of the bed body is the radial flow region 9, which is used to reduce the pressure drop change caused by the volume expansion of the fluid.

[0034] Specifically, the small-particle-size cold storage material 8 used in the radial flow region 3 can enhance heat transfer while improving the flow uniformity.

[0035] Specifically, the combination of the axial flow region 3 and the radial flow region 9 can reduce the floor area and improve the utilization rate of the vertical space in large-scale applications.

[0036] In summary, an axial and radial hybrid flow large-scale cold storage packed bed and method provided by the present invention include a bottom port, an axial flow region, large-particle-size cold storage materials, an internal channel, a radial flow region, small-particle-size energy storage materials, an annular channel, a top port, and a thermal insulation material. By combining the axial and radial directions and varying the particle sizes, the present invention improves the flow uniformity, effectively reduces the pressure drop and pump work loss, and thus improves the overall efficiency. On the other hand, since the vertical height of the radial flow is small, multiple layers can be stacked to reduce the floor area, thereby improving the bed integration and reducing the waste of floor area. At the same time, different partitions are made for the entire bed to achieve efficient cold preservation.

[0037] The above is the preferred implementation manner of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. It should be pointed out that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and changes can still be made, and these improvements and changes are also regarded as the protection scope of the present invention.

Claims

1. An axially and radially mixed-flow large-scale cold storage packed bed, characterized in that, Comprising a bed body, the bed body includes: Ports, which are divided into a bottom port (1) and a top port (19). The bottom port (1) is arranged at the bottom of the bed body, and the top port (19) is arranged at the top of the bed body; Channels, which include an internal channel and an annular channel. The internal channel is arranged at the middle position of the bed body, and the annular channel is arranged outside the internal channel; Flow regions, which are divided into an axial flow region (3) and a radial flow region. The axial flow region (3) is arranged at the lower end of the bed body, and the radial flow region is arranged at the upper end of the bed body; and the radial flow region is arranged between the internal channel and the annular channel; Energy storage materials, which include large-particle-size cold storage materials (4) and small-particle-size cold storage materials (8); Grids, which include a bottom grid (2), a radial flow inlet grid (5), a radial flow outlet grid (18), a first vertical grid (7), a second vertical grid (10), a third vertical grid (12), a fourth vertical grid (14), and a fifth vertical grid (16); Thermal insulation material (20), which is arranged outside the bed body.

2. The axial and radial hybrid flow large-scale cold storage packed bed according to claim 1, characterized in that The internal channel includes a first internal channel (6), a second internal channel (13), and a third internal channel (17). The third internal channel (17), the second internal channel (13), and the first internal channel (6) are arranged in sequence from top to bottom; the annular channel includes a first annular channel (11) and a second annular channel (15); the second annular channel (15) is arranged above the first annular channel (11); the first internal channel (6), the second internal channel (13), and the third internal channel (17) are arranged inside the radial flow region, and the first annular channel (11) and the second annular channel (15) are arranged outside the radial flow region (9), and the first annular channel (11) and the second annular channel (15) circumferentially wrap the radial flow region.

3. The axial and radial hybrid flow large-scale cold storage packed bed according to claim 1, characterized in that, The radial flow region includes a first radial flow region (901), a second radial flow region (902), a third radial flow region (903), and a fourth radial flow region (904); the fourth radial flow region (904), the third radial flow region (903), the second radial flow region (902), and the first radial flow region (901) are arranged in sequence from top to bottom.

4. The axial and radial hybrid flow large-scale cold storage packed bed according to claim 1, wherein, The large-particle-size cold storage materials (4) are arranged in the axial flow region (3), and the small-particle-size cold storage materials (8) are arranged in the radial flow region.

5. An axial and radial mixed-flow large-scale cold storage packed bed according to claim 1, characterized in that, The thermal insulation material (20) is pearlite or vitrified microsphere material.

6. The axial and radial hybrid flow large-scale cold storage packed bed according to claim 1, wherein The bottom grid (2) is arranged between the bottom port (1) and the axial flow region (3), the radial flow inlet grid (5) is arranged between the axial flow region (3) and the radial flow region, the radial flow outlet grid (18) is arranged between the radial flow region and the top port (19), the first vertical grid (7) is arranged between the first internal channel (6) and the first radial flow region (901), the second vertical grid (10) is arranged between the first radial flow region (901) and the first annular channel (11), the third vertical grid (12) is arranged between the second internal channel (13) and the second radial flow region (902), the fourth vertical grid (14) is arranged between the third radial flow region (903) and the second annular channel (15), and the fifth vertical grid (16) is arranged between the third internal channel (17) and the fourth radial flow region (904).

7. A cold storage method for an axially and radially mixed-flow large-scale cold storage packed bed according to any one of claims 1-6, characterized in that, It includes a cold storage process and a cold release process: Cold storage process: The low-temperature fluid flows in from the bottom port (1), enters the axial flow region (3) after passing through the bottom grid (2), the low-temperature fluid releases cold energy and stores it in the large-particle-size cold storage material (4), then flows into the first internal channel (6) through the radial flow inlet grid (5), and then the fluid enters the first radial flow region (901) through the first vertical grid (7). The low-temperature fluid exchanges cold energy with the small-particle-size cold storage material (8) and stores it in the small-particle-size cold storage material (8). Then it flows into the first annular channel (11) through the second vertical grid (10), and then flows into the second radial flow region (902) through the second vertical grid (10) and conducts cold energy exchange. Then it flows into the second internal channel (13) through the third vertical grid (12), and then flows into the third radial flow region (903) through the third vertical grid (12) and conducts cold energy exchange. Then it flows into the second annular channel (15) through the fourth vertical grid (14), and then flows into the fourth radial flow region (904) through the fourth vertical grid (14) and conducts cold energy exchange. Then it flows into the third internal channel (17) through the fifth vertical grid (16), and finally flows out of the top port (19) through the radial flow outlet grid (18), completing the cold storage process; Cold release process: The normal-temperature fluid flows in from the top port (19), enters the third internal channel (17) through the radial flow outlet grid (18), then enters the fourth radial flow area (904) through the fifth vertical grid (16), exchanges cold energy with the small-particle-size cold storage material (8) and absorbs the stored cold quantity; the fluid then flows into the second annular channel (15) via the fourth vertical grid (14), and then enters the third radial flow area (903) through the fourth vertical grid (14) for cold quantity exchange; subsequently, the fluid flows into the second internal channel (13) via the third vertical grid (12), and enters the second radial flow area (902) through the third vertical grid (12) to absorb the cold quantity in the small-particle-size cold storage material (8). After that, the normal-temperature fluid flows into the first annular channel (11) via the second vertical grid (10), and then enters the first radial flow area (901) through the second vertical grid (10) for cold quantity exchange; the fluid then enters the first internal channel (6) through the first vertical grid (7), and enters the axial flow area (3) through the radial flow inlet grid (5), where it absorbs the cold energy of the large-particle-size cold storage material (4). Finally, the fluid flows out from the bottom port (1) through the bottom grid (2), completing the cold release process.

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