Molten Salt Thermal Energy Storage Device and Molten Salt Thermal Energy Storage System

Abstract

Provided is a molten salt thermal storage device and a molten salt thermal storage system. The molten salt thermal storage device includes a plurality of molten salt storage tanks, each of which has an overflow port and a molten salt inlet located below the overflow port, the plurality of molten salt storage tanks being arranged in a vertical direction, the overflow port of an upper one of two adjacent molten salt storage tanks being connected to the molten salt inlet of a lower one of the two adjacent molten salt storage tanks so that the molten salt in the molten salt storage tank can overflow into the molten salt storage tank below, a plurality of overflow pipes, the plurality of overflow pipes being connected to any two adjacent molten salt storage tanks via the corresponding overflow pipes, a circulation pipe having an inlet connected to the lowermost overflow port of the plurality of molten salt storage tanks and an outlet connected to the uppermost molten salt inlet of the plurality of molten salt storage tanks, a heat exchanger, and a circulation pump provided in the circulation pipe or the overflow pipe.

Description

Cross-reference to Related Applications

[0001] This application claims the priority of the Chinese patent application with the application number 202210369285.0, which was filed in China on April 8, 2022, and all of its contents are incorporated herein by reference.

Technical Field

[0002] The present disclosure relates to the field of energy storage device technologies, and more specifically, to a molten salt heat storage device and a molten salt heat storage system.

Background Art

[0003] The molten salt heat storage technology has the advantages of low cost, safe and stable system, high operating temperature, environmental friendliness, and non-flammability. During heat storage, the temperature is increased by absorbing external heat, and during heat release, the temperature of the output medium is increased by heat exchange. In related technologies, the "single-tank" molten salt heat storage technology solution based on the principle of fluid thermocline has achieved preliminary applications, which can greatly reduce the construction investment cost of the molten salt heat storage system and simplify the related system. However, since molten salts with different temperature parameters are mixed and stored in the same tank body, higher requirements are imposed on the operation control of the system. Also, the "single-tank" molten salt heat storage technology solution cannot be easily expanded in capacity.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure aims to solve at least one of the technical problems in the related technologies to some extent. Therefore, the embodiments of the present disclosure propose a molten salt heat storage device and a molten salt heat storage system.

Means for Solving the Problems

[0005] In one aspect, the molten salt thermal energy storage device provided by the embodiments of the present disclosure is a plurality of molten salt storage tanks for storing molten salt, each of the molten salt storage tanks being provided with an overflow port and a molten salt inlet located below the overflow port. The plurality of molten salt storage tanks are arranged in the vertical direction, and the molten salt in the molten salt storage tank can overflow into the molten salt storage tank below it. The overflow port of the upper one of two adjacent molten salt storage tanks is connected to the molten salt inlet of the lower one of the two adjacent molten salt storage tanks. The plurality of molten salt storage tanks include a plurality of overflow pipes, any two adjacent molten salt storage tanks being connected through the corresponding overflow pipes. One end of the overflow pipe communicates with the corresponding overflow port, and the other end communicates with the corresponding molten salt inlet. A circulation pipe has an inlet connected to the overflow port of the lowermost one of the plurality of molten salt storage tanks and an outlet connected to the molten salt inlet of the uppermost one of the plurality of molten salt storage tanks. A heat exchanger is provided in the circulation pipe to perform heat exchange with the molten salt in the circulation pipe. A circulation pump is provided in the circulation pipe or the overflow pipe to drive the circulation flow of the molten salt.

[0006] Therefore, the molten salt thermal energy storage device according to the embodiments of the present disclosure has the advantages of being easy to expand the storage capacity of molten salt, easy to install, and cost-saving.

[0007] In some embodiments, the circulation pump is provided in the circulation pipe and is located between the heat exchanger and the lowermost molten salt storage tank.

[0008] In some embodiments, the upper part of the molten salt storage tank is an opening, the overflow port of each molten salt storage tank is provided at a position close to the upper edge of the molten salt storage tank, and the molten salt outlet of each molten salt storage tank is provided at a position close to the lower edge of the molten salt storage tank.

[0009] In some embodiments, each of the molten salt storage tanks includes a plurality of the overflow ports and a plurality of the molten salt inlets, the plurality of the overflow ports are arranged at intervals in the circumferential direction of the molten salt storage tank, and the plurality of the molten salt inlets are arranged at intervals in the circumferential direction of the molten salt storage tank.

[0010] In some embodiments, the molten salt heat storage device further includes a diverter provided at the bottom inside the molten salt storage tank, the diverter includes a diversion chamber and a plurality of diversion holes communicating with the diversion chamber, the diversion holes are opened at the upper part of the diverter, and the inlet of the diverter constitutes the molten salt inlet of the molten salt storage tank.

[0011] In some embodiments, the diverter includes a plurality of first diversion pipes and a plurality of second diversion pipes, the diversion holes are provided in each of the plurality of the first diversion pipes and the plurality of the second diversion pipes, the plurality of the first diversion pipes are arranged in parallel at intervals in the longitudinal direction of the molten salt storage tank, the plurality of the second diversion pipes are arranged in parallel at intervals in the width direction of the molten salt storage tank, and each of the first diversion pipes communicates with a plurality of the second diversion pipes.

[0012] In some embodiments, the ends of at least a part of the first diversion pipes extend to the outside of the molten salt storage tank to form the molten salt inlet, and the ends of at least a part of the second diversion pipes extend to the outside of the molten salt storage tank to form the molten salt inlet.

[0013] In some embodiments, the plurality of the overflow pipes include a plurality of first overflow pipes and a plurality of second overflow pipes, the plurality of the first overflow pipes are provided on one side of the plurality of the molten salt storage tanks, the plurality of the second overflow pipes are provided on the other side of the plurality of the molten salt storage tanks, and the plurality of the first overflow pipes and the plurality of the second overflow pipes are alternately arranged in the flowing direction of the molten salt.

[0014] In some embodiments, the inlet of the circulation pipe is detachably connected to the overflow port of the corresponding molten salt storage tank, and the outlet of the circulation pipe is detachably connected to the molten salt inlet of the corresponding molten salt storage tank.

[0015] In other aspects, embodiments of the present disclosure further provide a molten salt thermal energy storage system, and the system includes a molten salt thermal energy storage device which is the above-mentioned molten salt thermal energy storage device.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present disclosure will be described in detail, and an example of the embodiments is shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present disclosure and should not be construed as a limitation to the present disclosure.

[0018] While referring to the drawings, a molten salt thermal energy storage device 100 according to an embodiment of the present disclosure will be described. As shown in FIGS. 1 to 3, the molten salt thermal energy storage device 100 according to an embodiment of the present disclosure includes a plurality of molten salt storage tanks 1, a plurality of overflow pipes 2, a circulation pipe 3, a heat exchanger 4, and a circulation pump 5.

[0019] The molten salt storage tank 1 stores molten salt, and each molten salt storage tank 1 is provided with an overflow port 11 and a molten salt inlet 12 located below the overflow port 11. A plurality of molten salt storage tanks 1 are arranged in the vertical direction, and the overflow port 11 of the upper one of two adjacent molten salt storage tanks 1 is connected to the molten salt inlet 12 of the lower one of the two adjacent molten salt storage tanks 1 so that the molten salt in the molten salt storage tank 1 can overflow into the molten salt storage tank 1 below it. Any two adjacent molten salt storage tanks 1 are connected via a corresponding overflow pipe 2. One end of the overflow pipe 2 communicates with the corresponding overflow port 11, and the other end communicates with the corresponding molten salt inlet 12.

[0020] The inlet 31 of the circulation pipe 3 is connected to the overflow port 11 of the lowermost one of the plurality of molten salt storage tanks 1, and the outlet 32 of the circulation pipe 3 is connected to the molten salt inlet 12 of the uppermost one of the plurality of molten salt storage tanks 1. The heat exchanger 4 is provided in the circulation pipe 3 to perform heat exchange with the molten salt in the circulation pipe 3. The circulation pump 5 is provided in the circulation pipe 3 or the overflow pipe 2, and the circulation pump 5 drives the circulation flow of the molten salt.

[0021] The molten salt heat storage device 100 according to an embodiment of the present disclosure can improve the storage amount of molten salt in the molten salt heat storage device 100 and further improve the heat storage capacity of the molten salt heat storage device 100 by providing a plurality of molten salt storage tanks 1 suitable for storing molten salt. The plurality of molten salt storage tanks 1 are arranged in the vertical direction, and the overflow port 11 of the upper one of the two adjacent molten salt storage tanks 1 is connected to the molten salt inlet 12 of the lower one of the two adjacent molten salt storage tanks 1 so that the molten salt in the molten salt storage tank 1 can overflow into the lower molten salt storage tank 1. Thus, when the circulation pump 5 drives the circulation flow of the molten salt to exchange heat with the heat exchanger 4, the molten salt enters the uppermost one of the plurality of molten salt storage tanks 1 through the outlet 32 of the circulation pipe 3 and exchanges heat with the molten salt in the uppermost molten salt storage tank 1. As the molten salt in the uppermost molten salt storage tank 1 gradually increases, a part of the molten salt overflows from the overflow port 11 of the uppermost molten salt storage tank 1 and flows into the molten salt storage tank 1 adjacent to the uppermost molten salt storage tank 1 through the overflow pipe 2 under the action of gravity, and exchanges heat with the molten salt in this molten salt storage tank 1. During the continuous operation of the circulation pump 5, when the molten salt in the upper one of the two adjacent molten salt storage tanks 1 gradually increases, a part of the molten salt overflows into the lower one of the two adjacent molten salt storage tanks 1 through the overflow port 11 of the upper one of the two adjacent molten salt storage tanks 1 and can exchange heat with the molten salt in the lower one of the two adjacent molten salt storage tanks 1. That is, the plurality of molten salt storage tanks 1 arranged in the vertical direction can transport the molten salt in the upper one of the two adjacent molten salt storage tanks 1 to the lower one of the two adjacent molten salt storage tanks 1 through the overflow port 11 for heat exchange. This makes it convenient and energy-saving to transport molten salt between the plurality of molten salt storage tanks 1 arranged in the vertical direction. In addition to expanding the storage amount of molten salt in the molten salt heat storage device 100, the installation conditions are simple and the production cost can be saved.

[0022] Therefore, the molten salt heat storage device 100 according to the embodiments of the present disclosure has the advantages of being easy to expand the storage amount of molten salt, easy to install, and cost-saving.

[0023] As shown in FIGS. 1 to 3, the molten salt heat storage device 100 according to the embodiments of the present disclosure includes a plurality of molten salt storage tanks 1, a plurality of overflow pipes 2, a circulation pipe 3, a heat exchanger 4, and a circulation pump 5.

[0024] The plurality of molten salt storage tanks 1 are arranged in the vertical direction. The molten salt storage tanks 1 store molten salt, and the number of the molten salt storage tanks 1 is at least two, thereby improving the storage amount of molten salt in the molten salt heat storage device 100. Each molten salt storage tank 1 includes an overflow port 11 and a molten salt inlet 12 located below the overflow port 11. The upper part of the molten salt storage tank 1 is an open port, thereby making the air pressure in the molten salt storage tank 1 consistent with the outside and facilitating the overflow of the molten salt in the molten salt storage tank 1 from the overflow port 11 to the outside. The vertical direction is as shown by the arrows in FIGS. 1 and 2. For example, each of the plurality of molten salt storage tanks 1 includes a bottom plate 13, a first side plate 14 connected to the bottom plate 13, a second side plate 15, a third side plate 16, and a fourth side plate 17. The first side plate 14 and the third side plate 16 are arranged opposite to each other, and the second side plate 15 and the fourth side plate 17 are arranged opposite to each other.

[0025] As shown in FIG. 2, in some embodiments, the overflow port 111 of each molten salt storage tank 1 is provided at a position close to the upper edge of the molten salt storage tank 1, and the molten salt outlet of each molten salt storage tank 1 is provided at a position close to the lower edge of the molten salt storage tank 1. Thereby, each molten salt storage tank 1 can store more molten salt, and the storage amount of molten salt in the molten salt heat storage device 100 can be increased.

[0026] The overflow port 11 of the upper one of two adjacent molten salt storage tanks 1 is connected to the molten salt inlet 12 of the lower one of the two adjacent molten salt storage tanks 1 so that the molten salt in the molten salt storage tank 1 can overflow into the lower molten salt storage tank 1. Any two adjacent molten salt storage tanks 1 are connected via a corresponding overflow pipe 2. One end of the overflow pipe 2 communicates with the corresponding overflow port 11, and the other end communicates with the corresponding molten salt inlet 12. Specifically, one end (upper end) of the overflow pipe 2 is connected to the overflow port 11 of the upper one of the two adjacent molten salt storage tanks 1, and the other end (lower end) of the overflow pipe 2 is connected to the molten salt inlet 12 of the lower one of the two adjacent molten salt storage tanks 1. Thus, when molten salt is continuously injected into the upper one of two adjacent molten salt storage tanks 1, the upper one of the two adjacent molten salt storage tanks 1 can overflow a part of the molten salt from its overflow port 11 into the lower one of the two adjacent molten salt storage tanks 1 through the overflow pipe 2.

[0027] The inlet 31 of the circulation pipe 3 is connected to the overflow port 11 of the lowermost one of the plurality of molten salt storage tanks 1, and the outlet 32 of the circulation pipe 3 is connected to the molten salt inlet 12 of the uppermost one of the plurality of molten salt storage tanks 1. The heat exchanger 4 is provided in the circulation pipe 3 to perform heat exchange with the molten salt in the circulation pipe 3. The circulation pump 5 is provided in the circulation pipe 3 or the overflow pipe 2, and the circulation pump 5 drives the circulation flow of the molten salt. Thus, by the circulation pump 5, the molten salt in the lowermost one of the plurality of molten salt storage tanks 1 enters the circulation pipe 3, exchanges heat with the heat exchanger, and then is transported into the uppermost molten salt storage tank 1 for heat exchange.

[0028] In some embodiments, the circulation pump 5 is provided in the circulation pipe 3 and is located between the heat exchanger 4 and the lowermost molten salt storage tank 1. This facilitates the rapid transportation of the molten salt in the lowermost one of the plurality of molten salt storage tanks 1 into the circulation pipe 3 for heat exchange with the heat exchanger 4, and further improves the heat exchange efficiency.

[0029] As shown in FIGS. 1 and 2, in some embodiments, each molten salt storage tank 1 is provided with a plurality of overflow ports 11 and a plurality of molten salt inlets 12. The plurality of overflow ports 11 are arranged at intervals in the circumferential direction of the molten salt storage tank 1, and the plurality of molten salt inlets 12 are arranged at intervals in the circumferential direction of the molten salt storage tank 1. The plurality of overflow ports 11 and the plurality of molten salt inlets 12 facilitate setting the position and number of the overflow pipes 2 between two adjacent molten salt storage tanks 1 according to the actual situation. Specifically, by connecting the overflow pipe 2 to the overflow ports 11 and the molten salt inlets 12 on the same side of two adjacent molten salt storage tanks 1, the installation of the overflow pipe 2 can be facilitated. When it is necessary to improve the flow rate of the molten salt between two adjacent molten salt storage tanks 1, the number of overflow pipes between two adjacent molten salt storage tanks 1 can be increased. For example, both the overflow port 11 and the molten salt inlet 12 of each molten salt storage tank 1 are four. One overflow port 11 and one molten salt inlet 12 are provided on each of the first side plate 14, the second side plate 15, the third side plate 16, and the fourth side plate 17. In order to improve the overflow rate, two overflow pipes 2 are provided between two adjacent molten salt storage tanks 1.

[0030] As shown in FIG. 1, in some embodiments, the plurality of overflow pipes 2 include a plurality of first overflow pipes 21 and a plurality of second overflow pipes 22. The plurality of first overflow pipes 21 are provided on one side of the plurality of molten salt storage tanks 1, and the plurality of second overflow pipes 22 are provided on the other side of the plurality of molten salt storage tanks 1. The plurality of first overflow pipes 21 and the plurality of second overflow pipes 22 are arranged alternately in the flow direction of the molten salt. That is, in the flow direction of the molten salt, the plurality of overflow pipes 2 are arranged alternately on the sides of the molten salt storage tank 1, so that the overflow pipes 2 can be prevented from affecting each other. For example, in the flow direction of the molten salt, the first overflow pipe 2 (the first overflow pipe 21) may be provided on the right side of the molten salt storage tank 1, the second overflow pipe 2 (the second overflow pipe 22) may be provided on the left side of the molten salt storage tank 1, and the third overflow pipe 2 (the first overflow pipe 21) may be provided on the right side or the front and rear sides of the molten salt storage tank 1. The left-right direction and the front-rear direction are as shown by the arrows in FIGS. 1 and 2.

[0031] In some embodiments, the inlet 31 of the circulation pipe 3 is detachably connected to the overflow port 11 of the corresponding molten salt storage tank 1, and the outlet 32 of the circulation pipe 3 is detachably connected to the molten salt inlet 12 of the corresponding molten salt storage tank 1. Thus, when it is necessary to amplify the storage amount of the molten salt in the molten salt heat storage device 100, after adding molten salt storage tanks 1 above and below the original plurality of molten salt storage tanks 1, the inlet 31 of the circulation pipe 3 is connected to the overflow port 11 of the lowermost one among the plurality of molten salt storage tanks 1 after the addition, and the outlet 32 of the circulation pipe 3 can be connected to the molten salt inlet 12 of the uppermost one among the plurality of molten salt storage tanks 1 after the addition. Specifically, when a molten salt storage tank 1 is newly added above the original plurality of molten salt storage tanks 1, the outlet 32 of the circulation pipe 3 is connected to the molten salt storage tank 1 located at the uppermost position after the addition. When a molten salt storage tank 1 is newly added below the original plurality of molten salt storage tanks 1, the inlet 31 of the circulation pipe 3 is connected to the molten salt storage tank 1 located at the lowermost position after the addition.

[0032] As shown in FIGS. 2 and 3, the molten salt heat storage device 100 according to the embodiment of the present disclosure includes a diverter 6. The diverter 6 is provided at the bottom in the molten salt storage tank 1. The diverter 6 includes a diversion chamber and diversion holes 63 communicating with a plurality of diversion chambers. The diversion holes 63 are opened at the upper part of the diverter 6. The inlet of the diverter 6 constitutes the molten salt inlet 12 of the molten salt storage tank 1. Thus, the molten salt first enters the diversion chamber of the diverter 6, and then can exchange heat with the molten salt in the molten salt storage tank 1 through the diversion holes 63 communicating with the plurality of diversion chambers. The heat exchange of the molten salt can be made more uniform by the diversion holes 63 communicating with the plurality of diversion chambers, and the improvement of the heat exchange efficiency can be facilitated.

[0033] In some embodiments, the diverter 6 includes a plurality of first diverter pipes 61 and a plurality of second diverter pipes 62, and diversion holes 63 are provided in each of the plurality of first diverter pipes 61 and the plurality of second diverter pipes 62. The plurality of first diverter pipes 61 are arranged in parallel at intervals in the longitudinal direction of the molten salt storage tank 1, the plurality of second diverter pipes 62 are arranged in parallel at intervals in the width direction of the molten salt storage tank 1, and each first diverter pipe 61 communicates with the plurality of second diverter pipes 62. Thereby, the molten salt can uniformly exchange heat with the molten salt in the molten salt storage tank 1 through the diversion holes 63 above the plurality of first diverter pipes 61 and the plurality of second diverter pipes 62.

[0034] In some embodiments, the ends of at least a part of the first diverter pipes 61 extend to the outside of the molten salt storage tank 1 to form the molten salt inlet 12, and the ends of at least a part of the second diverter pipes 62 extend to the outside of the molten salt storage tank 1 to form the molten salt inlet 12. Thereby, it is facilitated for the molten salt to enter into the diverter 6 (the first diverter pipes 61 and the second diverter pipes 62). For example, the plurality of first diverter pipes 61 and the plurality of second diverter pipes 62 are provided on the bottom plate 13, the plurality of first diverter pipes 61 are arranged in parallel at intervals in the left - right direction, the plurality of second diverter pipes 62 are arranged in parallel at intervals in the front - rear direction, the two ends of one first diverter pipe 61 located in the middle extend to the outside of the molten salt storage tank 1 (the second side plate 15 and the fourth side plate 17) to form the molten salt inlet 12, and the two ends of one second diverter pipe 62 located in the middle extend to the outside of the molten salt storage tank 1 (the first side plate 14 and the third side plate 16) to form the molten salt inlet 12.

[0035] As shown in FIG. 1, in a specific embodiment, the plurality of molten salt storage tanks 1 includes a first molten salt storage tank 101, a second molten salt storage tank 102, a third molten salt storage tank 103, and a fourth molten salt storage tank 104, which are arranged in order from bottom to top. The inlet 31 of the circulation pipe 3 is connected to the overflow port 11 of the first molten salt storage tank 101, and the outlet 32 of the circulation pipe 3 is connected to the molten salt inlet 12 of the fourth molten salt storage tank 104. Thereby, the molten salt in the first molten salt storage tank 101 enters the circulation pipe 3 by the circulation pump 5, exchanges heat with the heat exchanger, and then is transported into the fourth molten salt storage tank 104 for heat exchange.

[0036] During heat storage, the low-temperature molten salt flows out from the overflow port 8 of the first molten salt storage tank 101. Under the action of the circulation pump 5, the molten salt in the circulation pipe 3 can absorb heat from the heat exchanger 4 and increase in temperature. Then, the high-temperature molten salt is introduced into the molten salt inlet 12 of the fourth molten salt storage tank 104 through the circulation pipe 3. When the high-temperature molten salt enters the diverter 6 of the fourth molten salt storage tank 104, it flows out uniformly from the diversion holes 63, and is stratified from bottom to top inside the fourth molten salt storage tank 104, with the high-temperature region gradually moving upward. When the high-temperature molten salt flows out from the overflow port 8 of the fourth molten salt storage tank 104, it flows into the molten salt inlet 12 of the third molten salt storage tank 103 through the overflow pipe 2 under the action of gravity, and goes through the heat exchange and flow process in the fourth molten salt storage tank 104 again. When the temperature of all the molten salt in the first molten salt storage tank 101 of the plurality of molten salt storage tanks 1 reaches the standard, the heat storage process is completed.

[0037] During heat release, the high-temperature molten salt flows out from the overflow port 11 of the first molten salt storage tank 101. Due to the action of the circulation pump 5, the molten salt in the circulation pipe 3 can release heat and be cooled by the heat exchanger 4. Then, the low-temperature molten salt is introduced into the molten salt inlet 12 of the fourth molten salt storage tank 104 through the circulation pipe 3. When the low-temperature molten salt enters the diverter 6 of the fourth molten salt storage tank 104, it flows out uniformly from the diversion holes 63 and stratifies from bottom to top inside the molten salt storage tank 1 of the D-layer opening, moving from a low temperature to a high temperature, and the low-temperature region gradually moves upward. When the low-temperature molten salt flows out from the overflow port 11 of the fourth molten salt storage tank 104, it flows into the molten salt inlet 12 of the third molten salt storage tank 103 through the overflow pipe 2 under the action of gravity, and undergoes the heat exchange and flow process in the fourth molten salt storage tank 104 again. When the temperature of all the molten salt in the first molten salt storage tank 101 of the plurality of molten salt storage tanks 1 reaches the standard, the heat release process is completed.

[0038] The embodiments of the present disclosure further propose a molten salt thermal energy storage system including the molten salt thermal energy storage device 100 according to the embodiments of the present disclosure.

[0039] Therefore, the molten salt thermal energy storage system according to the embodiments of the present disclosure has the advantages of being easy to expand the storage capacity of molten salt, easy to install the molten salt thermal energy storage device 10, and saving costs.

[0040] In the description of the present disclosure, terms such as "center", "longitudinal direction", "lateral direction", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial direction", "radial direction", "circumferential direction", etc. indicate the orientation or positional relationship shown based on the drawings. These are only for explaining and simplifying the description of the present disclosure, and do not indicate or imply that the shown device or element must have a specific orientation and be structured and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present disclosure.

[0041] Also, the terms "first" and "second" are used for illustrative purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of the recited technical features. Thus, features limited by "first" and "second" may include at least one of such features either explicitly or implicitly. In the description of the present disclosure, the meaning of "a plurality" is at least two, such as two, three, etc., unless specifically and clearly defined otherwise.

[0042] In the present disclosure, unless specifically defined and limited otherwise, terms such as "attach", "connect", "couple", "fix", etc. should be understood in a broad sense. For example, it may be a fixed connection, a removable connection, or an integral one, a mechanical connection, an electrical connection, capable of communicating with each other, a direct connection, an indirect connection through an intermediate medium, or an internal communication between two elements or an interaction relationship between two elements. Those skilled in the art can understand the specific meaning of the above terms in the present disclosure according to the specific circumstances.

[0043] In the present disclosure, unless specifically defined and limited otherwise, for the first feature to be located "above" or "below" the second feature, the first and second features may be in direct contact, or the first and second features may be indirectly in contact through an intermediate medium. Also, for the first feature to be located "on", "above", and "upper surface" of the second feature, it may indicate that the first feature is directly above or obliquely above the second feature, or it may simply indicate that the horizontal height of the first feature is higher than that of the second feature. For the first feature to be located "under", "below", and "lower surface" of the second feature, it may indicate that the first feature is directly below or obliquely below the second feature, or it may simply indicate that the horizontal height of the first feature is lower than that of the second feature.

[0044] In the present disclosure, terms such as "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the specification, the schematic description of the above terms does not necessarily target the same embodiment or example. Also, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. Further, those skilled in the art can combine or combine the different embodiments or examples described herein and the features of different embodiments or examples as long as they do not conflict with each other.

[0045] Although the above embodiments have been shown and described, the above embodiments are exemplary and should not be construed as limitations on the present disclosure. Any changes, modifications, substitutions, and variations made by those skilled in the art to the above embodiments are all included within the scope of the present disclosure.

Description of Reference Numerals

[0046] 1 Molten salt storage tank 2 Overflow pipe 3 Circulation pipe 4 Heat exchanger 5 Circulation pump 6 Divider 11 Overflow port 12 Molten salt inlet 13 Bottom plate 14 First side plate 15 Second side plate 16 Third side plate 17 Fourth side plate 21 First overflow pipe 22 Second overflow pipe 31 Inlet of the circulation pipe 32 Outlet of the circulation pipe 61 First diverter pipe 62 Second diverter pipe 63 Diverting hole 100 Molten salt thermal storage device 101 First molten salt storage tank 102 Second molten salt storage tank 103 Third molten salt storage tank 104 Fourth molten salt storage tank

Claims

1. A molten salt heat storage device, comprising: A plurality of molten salt storage tanks for storing molten salt, each of the molten salt storage tanks having an overflow port and a molten salt inlet located below the overflow port, the plurality of molten salt storage tanks being arranged in the vertical direction, and the molten salt in the molten salt storage tank being capable of overflowing into the molten salt storage tank below it. The overflow port of the upper one of two adjacent molten salt storage tanks is connected to the molten salt inlet of the lower one of the two adjacent molten salt storage tanks; a plurality of the molten salt storage tanks; A plurality of overflow pipes, wherein any two adjacent molten salt storage tanks are connected via the corresponding overflow pipes, one end of the overflow pipe communicates with the corresponding overflow port, and the other end communicates with the corresponding molten salt inlet; a plurality of the overflow pipes; A circulation pipe having an inlet connected to the overflow port of the lowermost one of the plurality of molten salt storage tanks and an outlet connected to the molten salt inlet of the uppermost one of the plurality of molten salt storage tanks; A heat exchanger provided in the circulation pipe so as to effect heat exchange with the molten salt in the circulation pipe; A circulation pump provided in the circulation pipe or the overflow pipe for driving the circulation flow of the molten salt. A molten salt heat storage device characterized by the above.

2. The molten salt heat storage device according to claim 1, wherein the circulation pump is provided in the circulation pipe and is located between the heat exchanger and the lowermost molten salt storage tank.

3. The upper part of the molten salt storage tank is an open port, the overflow port of each molten salt storage tank is provided at a position close to the upper edge of the molten salt storage tank, and the molten salt inlet of each molten salt storage tank is provided at a position close to the lower edge of the molten salt storage tank. The molten salt heat storage device according to claim 1, characterized by the above.

4. Each of the molten salt storage tanks is provided with a plurality of overflow ports and a plurality of molten salt inlets, the plurality of overflow ports are arranged at intervals in the circumferential direction of the molten salt storage tank, and the plurality of molten salt inlets are arranged at intervals in the circumferential direction of the molten salt storage tank. The molten salt heat storage device according to claim 1, characterized by the above.

5. The molten salt heat storage device further comprises a diverter provided at the bottom in the molten salt storage tank, The diverter includes a diversion chamber and a plurality of diversion holes communicating with the diversion chamber. The molten salt heat storage device according to claim 1, wherein the diversion holes are provided in the upper part of the diverter, and the inlet of the diverter constitutes the molten salt inlet of the molten salt storage tank.

6. The diverter includes a plurality of first diversion pipes and a plurality of second diversion pipes, the diversion holes are provided in each of the plurality of first diversion pipes and the plurality of second diversion pipes, the plurality of first diversion pipes are arranged in parallel at intervals in a first direction perpendicular to the vertical direction, the plurality of second diversion pipes are arranged in parallel at intervals in a second direction perpendicular to the vertical direction and the first direction, and each of the first diversion pipes communicates with the plurality of second diversion pipes. The molten salt heat storage device according to claim 5, characterized in that.

7. The molten salt heat storage device according to claim 6, wherein the ends of at least some of the first diversion pipes extend to the outside of the molten salt storage tank to form the molten salt inlet, and the ends of at least some of the second diversion pipes extend to the outside of the molten salt storage tank to form the molten salt inlet.

8. The plurality of overflow pipes include a plurality of first overflow pipes and a plurality of second overflow pipes, the plurality of first overflow pipes are provided on one side of the plurality of molten salt storage tanks, the plurality of second overflow pipes are provided on the other side of the plurality of molten salt storage tanks, and the plurality of first overflow pipes and the plurality of second overflow pipes are alternately arranged in the flow direction of the molten salt. The molten salt heat storage device according to claim 1, characterized in that.

9. The molten salt heat storage device according to claim 1, wherein the inlet of the circulation pipe is detachably connected to the overflow port of the corresponding molten salt storage tank, and the outlet of the circulation pipe is detachably connected to the molten salt inlet of the corresponding molten salt storage tank.

10. A molten salt heat storage system comprising the molten salt heat storage device according to any one of claims 1 to 9.

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