Rock heat storage system

Abstract

The utility model relates to the field of heat storage equipment, and provides a rock heat storage system which comprises a heat storage device filled with rock grains and provided with an inlet and an outlet, a baffle plate, a fan and an external heater, gas flow channels are formed in gaps among the rock grains, the baffle plate extends into the heat storage device to construct the gas flow channels into a snake shape, and the fan is arranged in the heat storage device. The outlet, the fan, the outer heater and the inlet are sequentially communicated to form a heat charging path, the outlet, the heat exchanger, the fan and the inlet are sequentially communicated to form a first heat release path, or the air inlet, the fan, the inlet, the outlet and the air outlet are sequentially communicated to form a second heat release path. By arranging the fan, air flow is enhanced, and the heat exchange efficiency of air and rock grains is improved. The communicating path of the inlet and the outlet is bent into a snake shape through the baffle plates, the uniformity of heat exchange between air and rock can be improved, and therefore the heat exchange efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of thermal storage equipment, and in particular to a rock thermal storage system. Background Technology

[0002] Thermal storage equipment typically uses off-peak electricity or waste electricity to convert electrical energy into thermal energy for storage. The stored thermal energy is then released when needed to improve energy efficiency.

[0003] Existing thermal storage equipment suffers from problems such as slow heat storage and release, and uneven heat distribution, resulting in poor utilization efficiency. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the defects of existing thermal storage equipment, such as slow heat storage and release and uneven heat storage and release, and to provide a rock thermal storage system.

[0005] The present invention solves the above-mentioned technical problems through the following technical solution:

[0006] A rock thermal storage system comprising:

[0007] A heat storage device has an internal filling cavity in which rock particles are stacked. Gas channels are formed in the gaps between the stacked rock particles. The heat storage device is provided with an inlet and an outlet that communicate with the gas channels.

[0008] A baffle plate is disposed within the filling cavity, which constructs the gas flow channel into a serpentine shape;

[0009] The fan and external heater are located outside the heat storage tank;

[0010] The outlet, the fan, the external heater, and the inlet are connected in sequence to form a heat charging path;

[0011] The rock thermal storage system further includes a heat exchanger disposed outside the thermal storage unit, and the outlet, the heat exchanger, the fan, and the inlet are sequentially connected to form a first heat release path; or, the rock thermal storage system further includes an air inlet and an air outlet, and the air inlet, the fan, the inlet, the outlet, and the air outlet are sequentially connected to form a second heat release path.

[0012] In this scheme, baffles are used to create a serpentine flow path for the gas between the rock particles, increasing the airflow path within the filling cavity and ensuring uniform and thorough heat exchange between the air and the rock. A fan drives the airflow for heat charging and discharging, improving heat charging and discharging efficiency. Placing the fan, external heater, and heat exchanger outside the heat storage unit increases the flexibility of their arrangement and facilitates future maintenance. Using rock particles for heat storage is environmentally friendly and cost-effective.

[0013] Preferably, the inlet and the outlet are located on the same side of the thermal storage unit, with the inlet near the bottom of the thermal storage unit and the outlet near the top of the thermal storage unit.

[0014] Preferably, the heat storage device includes a support layer and an insulation layer. The support layer is constructed using refractory bricks, refractory cement, and concrete, and forms the filling cavity inside. The insulation layer is made of insulation material and is wrapped around the outside of the support layer.

[0015] Preferably, the heat storage device has a first side and a second side opposite to each other, and the number of baffles is one. The baffle is fixed to the first side and sealed with the inner surface of the first side, and forms a gap with the inner surface of the second side.

[0016] Preferably, the heat storage device has a first side and a second side opposite to each other, and the number of baffles is multiple, including alternating first baffles and second baffles. The first baffle is fixed to the first side and sealed with the inner surface of the first side, forming a gap with the inner surface of the second side. The second baffle is fixed to the second side and sealed with the inner surface of the second side, forming a gap with the inner surface of the first side.

[0017] Preferably, the first side and the second side are two opposite sides along the length or width direction of the heat storage device;

[0018] The inlet and the outlet are located on the side of the baffle plate that is fixed to the heat storage unit, adjacent to each other. The inlet is close to the bottom of the heat storage unit, and the outlet is close to the top of the heat storage unit.

[0019] Preferably, the heat storage device further includes an internal heater inserted into the filling cavity.

[0020] Preferably, there is one baffle plate, and the internal heater is disposed on the side of the baffle plate near the outlet.

[0021] Preferably, there are multiple baffles, which are spaced apart along the length, width or height of the heat storage tank. At least some of the internal heaters are disposed between two baffles or on the side of the baffles near the outlet.

[0022] Preferably, the rock thermal storage system further includes a first pipeline, a second pipeline, a third pipeline, and a fourth pipeline. The fan is installed on the second pipeline, the external heater is installed on the third pipeline, and the heat exchanger is installed on the fourth pipeline. The outlet, the first pipeline, the second pipeline, the third pipeline, and the inlet are sequentially connected to form the heat charging path. A control valve is provided on the first pipeline. The outlet, the fourth pipeline, the second pipeline, and the inlet are sequentially connected to form the first heat dissipation path. Control valves are provided at both ends of the fourth pipeline, and the heat exchanger is located between the two control valves on the fourth pipeline.

[0023] Preferably, the rock thermal storage system further includes an air inlet control valve and an air outlet control valve, wherein the air inlet, the air inlet control valve, the fan, the inlet, the outlet, the air outlet control valve, and the air outlet are sequentially connected to form the second heat release path.

[0024] Preferably, the rock thermal storage system further includes a fifth pipeline, in which the second pipeline and the inlet are connected in the first heat release path through the fifth pipeline; or, in the second heat release path, the fan and the inlet are connected through the fifth pipeline.

[0025] Preferably, the third pipeline has a control valve at least at one end near the second pipeline, and at least one control valve on the third pipeline is located on the side of the external heater facing the second pipeline.

[0026] Preferably, the fifth pipeline has a control valve at least at one end near the second pipeline.

[0027] The positive and progressive effects of this utility model are as follows:

[0028] By setting baffles to construct the gas flow channels between rock particles into a serpentine shape, the flow path of air in the filling cavity can be increased, making the heat exchange between air and rock uniform and sufficient.

[0029] By installing fans to drive airflow for heat charging and discharging, the efficiency of heat charging and discharging can be improved. Placing the fans, external heaters, and heat exchangers outside the heat storage tank increases the flexibility of their arrangement.

[0030] By using rock pellets for thermal storage, it is environmentally friendly and low-cost. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the rock thermal storage system in Example 1;

[0032] Figure 2 for Figure 1 Simplified diagram;

[0033] Figure 3 This is a schematic diagram of the internal structure of the heat storage device in Example 2;

[0034] Figure 4 This is a schematic diagram of the internal structure of the heat storage device in Example 3;

[0035] Figure 5 This is a schematic diagram of the rock thermal storage system in Example 4;

[0036] Figure 6 This is a schematic diagram of the rock thermal storage system in Example 5.

[0037] Explanation of reference numerals in the attached figures:

[0038] Thermal storage system 100;

[0039] Thermal storage unit 1, inlet 11, outlet 12, filling cavity 13, support layer 14, insulation layer 15, first side 16, second side 17;

[0040] Baffle 2, first baffle 21, second baffle 22;

[0041] Fan 3;

[0042] External heater 4, internal heater 5;

[0043] Heat exchanger 6;

[0044] Air inlet 71, air outlet 72;

[0045] Pipeline 81, Pipeline 82, Pipeline 83, Pipeline 84, Pipeline 85, Pipeline 86, Pipeline 87, Pipeline 88, Pipeline 89;

[0046] Valve 1 (91), Valve 2 (92), Valve 3 (93), Valve 4 (94), Valve 5 (95), Valve 6 (96), Valve 7 (97), Valve 8 (98). Detailed Implementation

[0047] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0048] Example 1

[0049] This embodiment provides a rock thermal storage system (rock thermal storage system is referred to as thermal storage system). Figures 1-2 This is a schematic diagram provided for this embodiment.

[0050] like Figure 1 The thermal storage system 100 includes:

[0051] The heat storage device 1 has a filling cavity 13 inside for filling rock particles (rock particles are referred to as rocks). The rock particles are used as a heat storage medium to store heat energy. After the rock particles are stacked together, they form pores. These pores can form gas channels for air circulation. The heat storage device 1 has an inlet 11 and an outlet 12. The inlet 11, the gas channel in the filling cavity 13, and the outlet 12 are connected in sequence.

[0052] Baffle 2 is set in the filling cavity 13 to construct the gas flow channel formed between the rock particles into a serpentine shape;

[0053] Fan 3 is installed outside the heat storage tank 1 and is used to drive air flow;

[0054] An external heater 4 is installed outside the heat storage tank 1 and is used to heat the air;

[0055] Heat exchanger 6 is installed outside the heat storage tank 1 and is used to exchange heat with the fluid.

[0056] The outlet 12, fan 3, external heater 4, and inlet 11 are connected in sequence to form a heat charging path. When heat storage is required, the fan 3 drives the air to flow in the heat charging path. The air flows to the external heater 4 and is heated. Then it flows into the heat storage tank 1 from the inlet 11 to exchange heat with the rock particles, which raises the temperature of the rock particles and stores heat energy. The air temperature decreases after exchanging heat with the rock particles. After flowing out from the outlet 12, it flows to the external heater 4 again for heating. The cycle continues to transfer the heat from the external heater 4 to the filling cavity 13 and release it to the rock for storage.

[0057] The outlet 12, heat exchanger 6, fan 3, and inlet 11 are connected in sequence to form a heat release path, specifically referred to as the first heat release path. When heat needs to be released to the heat exchanger 6, the fan 3 drives the air to flow in the first heat release path. The air enters the heat storage tank 1 and flows through the pores formed between the high-temperature rock particles, carrying away heat. Then, it flows through the outlet 12 to the heat exchanger 6 for heat exchange and release. After releasing heat, the air re-enters the heat storage tank 1 through the fan 3 and inlet 11, carrying away the heat from the rock. This cycle continues, transferring the heat from the rock to the heat exchanger 6 for release.

[0058] By setting baffles 2 to construct the gas flow channels formed between rock particles into a serpentine shape, the flow path of air in the filling cavity 13 can be increased, so that the heat exchange between air and rock is uniform and sufficient.

[0059] By installing a fan 3 to drive airflow for heat charging and discharging, the heat charging and discharging efficiency can be improved. By placing the fan 3, external heater 4, and heat exchanger 6 outside the heat storage tank 1, the flexibility of their arrangement can be increased.

[0060] High-temperature thermal cycling resistant natural rocks can be selected through testing and evaluation. Compared to other thermal storage materials, this method reduces processing and manufacturing steps, lowers costs, and is more environmentally friendly. The high-temperature resistance of the rocks also enhances safety. The irregularly shaped natural rocks are naturally stacked and filled within the filling cavity 13. The gaps between the rocks naturally form airflow channels, eliminating the need for dedicated airflow channels within the filling cavity 13, thus simplifying the structure. Rocks with a size of 2 cm or larger are preferred.

[0061] In this embodiment, heat exchanger 6 is used for heat exchange with water. In the first heat dissipation path, high-temperature air flows to heat exchanger 6 to heat the water there, forming hot water, or heats the water to generate hot steam or saturated steam for use. In other embodiments, heat exchanger 6 can exchange heat with liquid media such as water or heat transfer oil for user use.

[0062] like Figure 1 The inlet 11 and outlet 12 are located on the same side of the thermal storage tank 1, facilitating connection between the inlet 11, outlet 12, and other structures along the heat charging path and the first heat dissipation path. The side of a structure in the thermal storage tank 1 can be understood as any side other than the top and bottom sides, such as the front, rear, left, and right sides; any side of a structure in the thermal storage tank 1 can be any side. Furthermore, as... Figure 1 The inlet 11 is located near the bottom of the thermal storage unit 1, and the outlet 12 is located near the top of the thermal storage unit 1. When the thermal storage unit 1 is charged with heat, hot air flows from bottom to top. When the charging is finished, the temperature of the lower rock is higher than that of the upper rock. If the inlet 11 and outlet 12 of the thermal storage unit 1 are closed, the hot air inside the thermal storage unit 1 will naturally rise and the cold air will naturally fall, resulting in natural convection of hot and cold air inside the thermal storage unit 1. Combined with the effects of heat radiation and heat conduction between materials, the temperature inside the thermal storage unit 1 gradually becomes uniform, thereby reducing the temperature difference between the upper and lower parts of the rock until the temperature tends to be uniform. In other embodiments, the inlet 11 and outlet 12 can be located on different sides of the thermal storage unit 1, and / or, the outlet 12 can be located at the top of the thermal storage unit 1.

[0063] The thermal storage unit 1 is constructed using refractory bricks, which allows for a larger size to increase heat storage capacity. It also reduces the cost of the thermal storage unit 1 for large-scale heat storage, lowers transportation costs, and facilitates construction. Specifically, in this embodiment, the thermal storage unit 1 includes a support layer 14, which can be, but is not limited to, constructed using refractory bricks, refractory cement, insulating concrete, or insulating mortar. A filling cavity 13 filled with rock particles is formed within the support layer 14. The thermal storage unit 1 also includes an insulation layer 15, made of insulating bricks or other insulating materials, wrapped around the outside of the support layer 14. The thermal storage unit 1 can be directly stacked on the ground, such as... Figure 1The bottom surface of the heat storage unit 1 is planar. Specifically, in this embodiment, the heat storage unit 1 is rectangular and has a simple structure. Rocks can be filled and baffle plates 2 can be laid during the construction of the heat storage unit 1.

[0064] like Figure 1 In this embodiment, there is one baffle plate 2. The heat storage tank 1 has a first side 16 and a second side 17. The baffle plate 2 is fixed to the first side 16 and sealed to the inner surface of the first side 16 to prevent air from passing through or bypassing the baffle plate 2 at the fixed point between the baffle plate 2 and the heat storage tank 1, connecting the inlet 11 and the outlet 12. A gap is formed between the baffle plate 2 and the inner surface of the second side 17. After the air enters the interior of the heat storage tank 1 from the inlet 11, it is blocked by the baffle plate 2 and flows around the baffle plate 2 through the gap between the baffle plate 2 and the second side 17 to the outlet 12.

[0065] Figure 2 The simplified thermal storage device 1 is indicated by a dashed line. (Example:) Figure 2 The rock thermal storage system 100 also includes multiple pipelines, specifically including a first pipeline 81, a second pipeline 82, a third pipeline 83, a fourth pipeline 84, a fifth pipeline 85, a sixth pipeline 86, and a seventh pipeline 87. A fan 3 is installed on the second pipeline 82, an external heater 4 is installed on the third pipeline 83, and a heat exchanger 6 is installed on the fourth pipeline 84. The outlet 12, the sixth pipeline 86, the first pipeline 81, the second pipeline 82, the third pipeline 83, the seventh pipeline 87, and the inlet 11 are sequentially connected to form a heat charging path. The outlet 12, the sixth pipeline 86, the fourth pipeline 84, the second pipeline 82, the fifth pipeline 85, and the seventh pipeline 87 are sequentially connected to form a first heat dissipation path. In the attached diagram, arrows or short straight lines with arrows are used to indicate the flow direction of air and water at the heat exchanger 6.

[0066] By connecting the third pipe 83 and the fifth pipe 85 in parallel, the external heater 4 on the third pipe 83 is bypassed during heat release, which reduces airflow resistance and heat loss, thereby improving heat exchange efficiency. In other embodiments, the fifth pipe 85 may be omitted, and heat release occurs through the third pipe 83, simplifying the structure. In other embodiments, the sixth pipe 86 and / or the seventh pipe 87 may be omitted.

[0067] like Figure 2The thermal storage system 100 is equipped with multiple control valves, specifically valve 1 (91), valve 2 (92), valve 3 (93), valve 4 (94), and valve 5 (95). Valve 1 (91) is located on the first pipe 81; valve 2 (92) is located on the third pipe 83, on the side of the external heater 4 facing the second pipe 82 (the orientation of the valves and pipes can be understood as their orientation along the airflow path); valve 3 (93) is located on the fifth pipe 85; valves 4 (94) and 5 (95) are located on the fourth pipe 84, and the heat exchanger 6 is located between valves 4 (94) and 5 (95). The control valves can be on / off valves or regulating valves with both on / off and flow regulation functions. When heat charging is required, valves 1 (91) and 2 (92) are open, and valves 3 (93), 4 (94), and 5 (95) are closed. When heat release is required, valves 1 (91) and 2 (92) are closed, and valves 3 (93), 4 (94), and 5 (95) are open. Furthermore, valve 2 92 is located at one end of the third pipe 83 near the second pipe 82, valve 3 93 is located at one end of the fifth pipe 85 near the second pipe 82, and valves 4 94 and 5 95 are located at both ends of the fourth pipe 84, respectively. In other embodiments, control valves can be installed at both ends of the first pipe 81, the third pipe 83, the fourth pipe 84, and the fifth pipe 85. These valves can close unused pipes during heat charging and releasing to prevent air from entering unused pipes and trapping heat, thereby improving heat exchange efficiency.

[0068] Example 2

[0069] This embodiment provides a rock thermal storage system. The main difference between this embodiment and embodiment 1 is the size of the thermal storage device and the setting of the baffle plate. The setting of the pipeline and control valve can refer to embodiment 1 or other embodiments. Figure 3 This is a schematic diagram of the structure of this embodiment.

[0070] like Figure 3 The number of baffles 2 is multiple and an odd number, specifically three. These three baffles 2 are arranged sequentially along the height direction of the heat storage tank 1. Each baffle 2 includes an alternately arranged first baffle 21 and second baffle 22. The heat storage tank 1 has a first side 16 and a second side 17 facing each other. The first baffle 21 is fixed to the first side 16 and seals its inner surface, forming a gap with the inner surface of the second side 17. The second baffle 22 is fixed to the second side 17 and seals its inner surface, forming a gap with the inner surface of the first side 16. In this embodiment, the first side 16 and the second side 17 are two opposing sides along the length direction of the heat storage tank 1. In other embodiments, the first side 16 and the second side 17 may be two opposing sides along the length, width, or height direction of the heat storage tank 1.

[0071] Furthermore, both inlet 11 and outlet 12 are located on the first side 16, with inlet 11 near the bottom of the thermal storage unit 1 and outlet 12 near the bottom of the thermal storage unit 1. This arrangement ensures that the communication path between inlet 11 and outlet 12 within the thermal storage unit 1 is sufficiently long, resulting in sufficiently uniform heat exchange between the air and the rock particles. In other embodiments, inlet 11 and outlet 12 can be located on different sides of the thermal storage unit 1 or near different sides; for example, if the uppermost baffle 2 in this embodiment is removed, the number of baffles 2 is multiple and even. Correspondingly, outlet 12 can be located on the second side 17 near the top of the thermal storage unit 1, or on the top of the thermal storage unit 1 near the second side 17.

[0072] In this embodiment, the extension direction of the baffle 2 is perpendicular to the H direction, and multiple baffles 2 are arranged parallel to each other along the H direction. In other embodiments, the shape, number, and arrangement of the baffles 2 can be adjusted according to specific needs. For example, the baffles 2 can be extended along the length, width, or height of the heat storage tank 1; or multiple baffles 2 can be spaced apart along the length, width, or height of the heat storage tank 1. When the arrangement of the baffles 2 changes, the positions of the inlet 11 and the outlet 12 can be adjusted accordingly to optimize the gas flow path within the filling cavity 13.

[0073] Example 3

[0074] This embodiment provides a rock thermal storage system. The main difference between this embodiment and embodiment 2 is that this embodiment is equipped with an internal heater. The configuration of the thermal storage device, pipelines, and control valves can refer to embodiment 1 or other embodiments. Figure 4 This is a schematic diagram of this embodiment.

[0075] After air enters the heat storage tank 1 through inlet 11, its temperature drops after exchanging heat with the rock particles, resulting in a higher temperature for the lower rock particles and a lower temperature for the upper rock particles. For example... Figure 4An internal heater 5 is installed inside the thermal storage tank 1, located within the filling cavity 13. This internal heater 5 heats the air and rock particles, improving the uniformity of heat storage in different parts of the rock. Specifically, the internal heater 5 is positioned between adjacent baffles 2 to heat the rock and air located in the middle of the filling cavity 13 along the H direction. This ensures more uniform heat storage in the lower and middle parts of the rock when the fan 3 is running. The internal heater 5 is encased in rock, resulting in high system integration. The heat radiated and conducted by the internal heater 5 is also absorbed by the rock, reducing heat loss and improving heat storage efficiency. When the fan 3 and all control valves are turned off, the air temperature in the lower and middle parts of the thermal storage tank 1 along the H direction is higher than the air temperature in the upper part. The cooler air naturally flows downwards, and the warmer air naturally flows upwards, thus facilitating a relatively uniform temperature distribution among the rocks within the thermal storage tank 1. In other embodiments, when multiple baffles 2 are provided, at least some of the internal heaters 5 can be provided between two adjacent baffles 2; or at least some of the heaters can be provided on the side of the baffle 2 closest to the outlet 12, for example, in this embodiment, the internal heater 5 can be provided above the uppermost baffle 2. In other embodiments, when one baffle 2 is provided, it is preferable to provide the internal heater 5 on the side of the baffle 2 closest to the outlet 12, for example, in embodiment 1, it is preferable to provide the internal heater 5 above the baffle 2. Therefore, the internal heater 5 mainly plays the following roles: (1) It supplements the heating limitations of the external heater 4. During the heating process of the external heater 4, it is limited by the upper limit temperature of the electric heating rod metal, the heating cylinder metal and the connecting pipe metal (such as below 600 degrees Celsius). If it is higher than this temperature, an electric heater made of ultra-high temperature resistant material needs to be selected, which is costly. At this time, the external heater 4 can be turned off, and only the internal heater 5 can be turned on to directly heat the rock. (2) The internal heater 5 can achieve temperature gradient coordination with the external heater 4. For example: the upper limit of the heating temperature of the external heater 4 is <600 degrees Celsius. The temperature inside the heat storage tank decreases with increasing height. Assuming that the temperature is 500 degrees Celsius near the inlet, 400 degrees Celsius near the outlet, and 300 degrees Celsius near the outlet, the temperature is low and the heat storage capacity of the rock is largely idle and undeveloped. At this time, the internal heater 5 is used to raise its temperature. The placement point of the internal heater is selected by combining the temperature distribution cloud map of the simulation analysis. By accurately controlling the switching of the internal heater through the temperature measurement points in each area, most of the rock can be heated to 600 degrees Celsius to the upper limit of the rock temperature resistance, so as to fully develop its heat storage capacity and increase the heat storage capacity. (3) The combination of the external heater 4 and the internal heater 5 can form a flexible and adjustable charging speed. For example, if the external heater is 100KW, one internal heater is 100KW, and another internal heater is 100kw, and all of them are turned on, it is a 300kw fast charging mode. If only one 100kw is turned on, it is a slow charging mode.

[0076] The external heater 4 and the internal heater 5 can be electric heaters, such as those using off-peak electricity, waste electricity, peak-shaving and frequency-modulated electricity, solar and wind power generation, etc. Other energy sources can also be used; for example, a high-temperature waste heat recovery boiler, which uses high-temperature waste heat to heat low-temperature air into high-temperature air, which is then sent to the heat storage tank 1 to store heat; or high-temperature extracted steam from a power generation system, which heats low-temperature air into high-temperature air, which is then sent to the heat storage tank 1 to store heat. Multiple energy sources can be used simultaneously; for example, the external heater 4 can be heated by high-temperature waste heat, and the internal heater 5 can be heated electrically.

[0077] Example 4

[0078] This embodiment provides a rock thermal storage system. The main difference between this embodiment and embodiment 1 is the setting of the heat release path. The setting of the thermal storage device, baffle plate and heat charging path can refer to embodiment 1 or other embodiments. Figure 5 This is a schematic diagram of this embodiment.

[0079] like Figure 5 The rock thermal storage system 100 includes an air inlet 71 and an air outlet 72. The air inlet 71, the fan 3, the inlet 11, the outlet 12, and the air outlet 72 are connected in sequence to form a heat release path, which is called the second heat release path. After the cold air enters the rock thermal storage system 100 from the air inlet 71, it enters the heat storage tank 1 and exchanges heat with the rock to become hot air. Then it flows out from the air outlet 72 to provide hot air to the user.

[0080] Specifically, the piping of the rock thermal storage system 100 also includes an eighth pipe 88 and a ninth pipe 89. An air inlet 71 is located at one end of the eighth pipe 88, and an air outlet 72 is located at one end of the ninth pipe 89. Control valves include valve six 96 (air inlet control valve) on the eighth pipe 88 and valve seven 97 (air outlet control valve) on the ninth pipe 89. The air inlet 71, eighth pipe 88, second pipe 82, fifth pipe 85, seventh pipe 87, inlet 11, outlet 12, sixth pipe 86, ninth pipe 89, and air outlet 72 are sequentially connected to form a second heat release path. During heat charging, valves three 93, six 96, and seven 97 are closed, and the other control valves are opened; during heat release, valves three 93, six 96, and seven 97 are opened, and the other valves are closed.

[0081] Implementation 5

[0082] This embodiment provides a rock thermal storage system. The main difference between this embodiment and embodiment 1 is the setting of the heat release path. The setting of the thermal storage device, baffle plate and heat charging path can refer to embodiment 1 or other embodiments. Figure 6 This is a schematic diagram of this embodiment.

[0083] like Figure 6The rock thermal storage system 100 has two heat release paths. The first heat release path is formed by the sequential connection of outlet 12, sixth pipe 86, fourth pipe 84, second pipe 82, fifth pipe 85, seventh pipe 87, and inlet 11. The first pipe 81 is equipped with valve 1 91. The external heater 4 on the third pipe 83 is equipped with valve 2 92 on the side near the second pipe 82. The fifth pipe 85 is equipped with valve 3 93. The four pipes 84 are equipped with valve 4 94 and valve 5 95 at both ends. The heat exchanger 6 is located on the fourth pipe 84 between valve 4 94 and valve 5 95. Air inlet 71, eighth pipe 88, second pipe 82, fifth pipe 85, seventh pipe 87, inlet 11, outlet 12, sixth pipe 86, ninth pipe 89, and air outlet 72 are connected in sequence to form a second heat release path; valve 6 96 is provided on the eighth pipe 88, and the eighth pipe 88 and the fourth pipe 84 are connected between the heat exchanger 6 and valve 5 95; valve 7 97 is provided on the ninth pipe 89, and valve 88 98 is provided on the fourth pipe 84 between valve 4 94 and the heat exchanger 6, and the ninth pipe 89 and the fourth pipe 84 are connected between valve 4 94 and valve 88.

[0084] When heat needs to be charged, valves 1 (91) and 2 (92) are open, and the other valves are closed. When heat needs to be released through the first heat exchange path, valves 1 (91), 2 (92), 6 (96), and 7 (97) are closed, and the other valves are open. When heat needs to be released through the second heat exchange path, valves 1 (91), 2 (92), and 8 (98) are closed, and the other valves are open.

[0085] Overall, this utility model has the following advantages:

[0086] Using natural rocks, it is pollution-free and more environmentally friendly; compared with other heat storage materials, it reduces processing and manufacturing steps, thus lowering costs.

[0087] The addition of a fan enhances convective heat transfer, increases the system's heat charging and discharging speed, and improves system energy efficiency.

[0088] The addition of fans makes the system more flexible and adjustable. For example, by using variable frequency fans, the air speed can be adjusted by adjusting the fan frequency, making the heat dissipation power adjustable and improving the system's flexibility and adaptability.

[0089] Utilize off-peak electricity, abandoned electricity, peak-shaving and frequency-regulating electricity, wind power, solar power, and high-temperature waste heat for heating and heat storage to reduce costs;

[0090] By using non-metallic materials such as refractory bricks and insulating bricks to construct the thermal storage device 1, the use of high-temperature resistant metal materials can be reduced, which can greatly adapt to high upper limit thermal storage (such as above 600 degrees Celsius, such as above 800 degrees Celsius), and realize the construction of ultra-large-scale low-cost thermal storage device 1; make full use of the thermal storage temperature range of rocks, increase thermal storage density, and produce high-grade thermal energy.

[0091] Add baffle 2 to ensure sufficient heat exchange and increase heat transfer efficiency;

[0092] An internal heater 5 is added to form multi-point heating and equalize the temperature inside the heat storage tank 1; direct heating and flow heat exchange are combined, and heat convection and radiation heat transfer are carried out in tandem to improve the heat charging speed;

[0093] When the rocks in the heat storage tank 1 are heated, hot air conducts heat from bottom to top, resulting in a temperature that is higher at the top and lower at the bottom. When the fan 3 is turned off and the tank is left to stand, natural circulation is used to allow the temperature to rise and fall, gradually making the temperature at the top and bottom more uniform and maximizing the utilization of the rock's heat storage capacity.

[0094] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A rock thermal storage system, characterized in that, It includes: A heat storage device has an internal filling cavity in which rock particles are stacked. Gas channels are formed in the gaps between the stacked rock particles. The heat storage device is provided with an inlet and an outlet that communicate with the gas channels. A baffle plate is disposed within the filling cavity, which constructs the gas flow channel into a serpentine shape; The fan and external heater are located outside the heat storage tank; The outlet, the fan, the external heater, and the inlet are connected in sequence to form a heat charging path; The rock thermal storage system further includes a heat exchanger disposed outside the thermal storage unit, and the outlet, the heat exchanger, the fan, and the inlet are sequentially connected to form a first heat release path; or, the rock thermal storage system further includes an air inlet and an air outlet, and the air inlet, the fan, the inlet, the outlet, and the air outlet are sequentially connected to form a second heat release path.

2. The rock thermal storage system as described in claim 1, characterized in that, The inlet and the outlet are located on the same side of the thermal storage unit, with the inlet near the bottom of the thermal storage unit and the outlet near the top of the thermal storage unit.

3. The rock thermal storage system as described in claim 1, characterized in that, The heat storage device includes a support layer and an insulation layer. The support layer is constructed of refractory bricks and has a filling cavity inside. The insulation layer is made of insulation material and is wrapped around the outside of the support layer.

4. The rock thermal storage system as described in claim 1, characterized in that, The thermal storage device has a first side and a second side opposite to each other; The number of baffles is one, the baffle is fixed to the first side and sealed with the inner surface of the first side, and forms a gap with the inner surface of the second side; or, the number of baffles is multiple, including alternating first baffles and second baffles, the first baffle is fixed to the first side and sealed with the inner surface of the first side, and forms a gap with the inner surface of the second side, the second baffle is fixed to the second side and sealed with the inner surface of the second side, and forms a gap with the inner surface of the first side.

5. The rock thermal storage system as described in claim 4, characterized in that, The first side and the second side are two opposite sides along the length or width direction of the heat storage device; The inlet and the outlet are located on the side of the baffle plate that is fixed to the heat storage unit, adjacent to each other. The inlet is close to the bottom of the heat storage unit, and the outlet is close to the top of the heat storage unit.

6. The rock thermal storage system as described in claim 1, characterized in that, The heat storage device also includes an internal heater inserted into the filling cavity.

7. The rock thermal storage system as described in claim 6, characterized in that, The number of the baffles is one, and the internal heater is disposed on the side of the baffles near the outlet; Alternatively, there may be multiple baffles, which are spaced apart along the length, width, or height of the heat storage tank, with at least some of the internal heaters disposed between two baffles or on the side of the baffle near the outlet.

8. The rock thermal storage system as described in claim 1, characterized in that, The rock thermal storage system further includes a first pipeline, a second pipeline, a third pipeline, and a fourth pipeline. The fan is installed on the second pipeline, the external heater is installed on the third pipeline, and the heat exchanger is installed on the fourth pipeline. The outlet, the first pipeline, the second pipeline, the third pipeline, and the inlet are sequentially connected to form the heat charging path. A control valve is provided on the first pipeline. The outlet, the fourth pipeline, the second pipeline, and the inlet are sequentially connected to form the first heat dissipation path. Control valves are provided at both ends of the fourth pipeline, and the heat exchanger is located between the two control valves on the fourth pipeline. Alternatively, the rock thermal storage system may further include an air inlet control valve and an air outlet control valve, wherein the air inlet, the air inlet control valve, the fan, the inlet, the outlet, the air outlet control valve, and the air outlet are sequentially connected to form the second heat release path.

9. The rock thermal storage system as described in claim 8, characterized in that, The rock thermal storage system further includes a fifth pipeline, in which the second pipeline and the inlet are connected through the fifth pipeline in the first heat release path; or, in the second heat release path, the fan and the inlet are connected through the fifth pipeline.

10. The rock thermal storage system as described in claim 9, characterized in that, The third pipeline is provided with a control valve at least at one end near the second pipeline, and at least one control valve on the third pipeline is located on the side of the external heater facing the second pipeline; The fifth pipeline is equipped with a control valve at least at one end near the second pipeline.

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