Heat energy storage method and system based on multi-section particle packed bed

Abstract

The embodiment of the invention provides a thermal energy storage method and system based on a multi-section particle packed bed, the thermal energy storage system comprises an electric heating module, a fluidized bed thermal energy storage module and a fixed bed thermal energy storage module, the fluidized bed thermal energy storage module comprises a fluidized bed and first particles filled in a cavity of the fluidized bed, the electric heating module is partially arranged in the fluidized bed cavity and is in contact with the first particles, the fixed bed heat energy storage module is connected with the fluidized bed heat energy storage module, and the fixed bed heat energy storage module comprises a plurality of fixed beds connected in parallel and second particles filled in the fixed beds. According to the embodiment of the invention, rapid heat storage of the fluidized bed and the fixed beds is realized, the heat storage density is improved, heat storage is performed through a plurality of fixed beds, and the defect that the size of the fluidized bed is too large when the fluidized bed is adopted for heat storage can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to a thermal energy storage method and system based on a multi-stage particle packed bed. Background Art

[0002] In order to meet the mismatch between renewable energy generation such as wind and solar power and user needs, heat storage technology, as the mainstream technology in energy storage technology, has received extensive attention in industrial applications. High heat storage temperature and large device capacity are the inevitable trend of the development of heat storage technology. Among them, one of the core technical indicators of large-scale heat storage technology industrial application is the requirement of high power density. That is, to achieve rapid heat charging and heat release process, especially to shorten the "time window" of heat charging, which can greatly improve the storage of valley power of wind power and solar power generation.

[0003] However, the current solar thermal power generation technology based on fluidized bed technology has the disadvantages of low heat storage density and large size. Summary of the invention

[0004] In view of the above problems, a thermal energy storage method and system based on a multi-stage particle packed bed is proposed to overcome the above problems or at least partially solve the above problems, including:

[0005] A thermal energy storage system based on a multi-stage particle packed bed, the thermal energy storage system comprising an electric heating module, a fluidized bed thermal energy storage module and a fixed bed thermal energy storage module, the fluidized bed thermal energy storage module comprising a fluidized bed and first particles filled in a cavity of the fluidized bed, the electric heating module is partially placed inside the cavity of the fluidized bed and in contact with the first particles, the fixed bed thermal energy storage module is connected to the fluidized bed thermal energy storage module, the fixed bed thermal energy storage module comprises a plurality of parallel fixed beds and second particles filled in the fixed beds;

[0006] The electric heating module is used to heat the first particles when powered on;

[0007] The fluidized bed thermal energy storage module is used to exchange heat energy between the heated first particles and the fluid working medium introduced into the fluidized bed chamber, and output the fluid working medium to the fixed bed thermal energy storage module;

[0008] The fixed bed thermal energy storage module is used to receive the heated fluid medium output by the fluidized bed, and use the fluid medium to perform heat exchange with the second particles in the fixed bed to store thermal energy in the second particles of the fixed bed.

[0009] Optionally, the thermal energy storage system further comprises a water heating pipeline module; the water heating pipeline module is partially placed in the upper part of the fluidized bed cavity and contacts with the third particles filled in the upper part of the fluidized bed cavity, and the electric heating module contacts with the first particles filled in the lower part of the fluidized bed cavity;

[0010] The fixed bed thermal energy storage module is used to heat the fluid medium passing into the fixed bed using the heat stored in the second particles, and output the heated fluid medium to the fluidized bed thermal energy storage module;

[0011] The fluidized bed thermal energy storage module is used to introduce the fluid medium that has exchanged heat with the second particles in the fixed bed, and to exchange heat energy between the fluid medium and the third particles, and to use the third particles to heat the water introduced into the water heating pipeline module.

[0012] Optionally, valves are provided between adjacent fixed beds; the fixed bed thermal energy storage module is used to control the valves between the fixed beds during the heat storage stage so that the heated fluid working medium is sequentially introduced into the multiple fixed beds in series.

[0013] Optionally, the fixed bed thermal energy storage module is used to control valves of adjacent fixed beds during the heat release stage to sequentially introduce a fluid working medium into each fixed bed connected in parallel for heating.

[0014] Optionally, the middle part of the cavity between the upper part of the cavity and the lower part of the fluidized bed heat storage device is fixedly filled with fourth particles for temperature control.

[0015] Optionally, the thermal energy storage system includes an air supply module, and the air supply module is composed of a fan and an air supply pipeline;

[0016] The fan is used to transport fluid to the fluidized bed through an air supply pipeline connected to the fluidized bed thermal energy storage module when the electric heating module heats the air medium and the fixed bed thermal energy storage module is in the heat storage stage; and to transport fluid to each fixed bed connected in parallel through an air supply pipeline connected to the fixed bed thermal energy storage module when the fixed bed thermal energy storage module is in the heat release stage.

[0017] Optionally, the thermal energy storage system is used to control the fan to be in an off state and close the inlet and outlet of the fluidized bed thermal energy storage module and the fixed bed thermal energy storage module after each fixed bed is heated to a target temperature.

[0018] Optionally, the fluidized bed thermal energy storage module also includes an air distribution plate in the fluidized bed. When the first particles and the third particles are the same type of particles, an air distribution plate is arranged at the bottom of the fluidized bed. When the first particles and the third particles are different types of particles, a first air distribution plate is arranged at the bottom of the fluidized bed, and a second air distribution plate is arranged between the water heating pipe module and the electric heating module.

[0019] A multi-stage packed bed thermal energy storage method is applied to the thermal energy storage system as described above, and the method comprises:

[0020] heating the first particles in an energized state;

[0021] The heated first particles exchange heat energy with the fluid medium introduced into the fluidized bed chamber, and output the fluid medium to the fixed bed of the fixed bed thermal energy storage module;

[0022] The fluid working medium is used to perform heat exchange with the second particles in the fixed bed, so as to store thermal energy in the second particles of the fixed bed.

[0023] Optionally, the method further comprises:

[0024] The heat stored in the second particles is used to heat the fluid medium passing into the fixed bed, and the heated fluid medium is output to the fluidized bed thermal energy storage module;

[0025] In the fluidized bed of the fluidized bed thermal energy storage module, the fluid working medium exchanges heat energy with third particles filled in the fluidized bed, and the third particles are used to heat water introduced into the water heating pipeline module.

[0026] The embodiments of the present invention have the following advantages:

[0027] In the embodiment of the present invention, the electric heating module converts electrical energy into thermal energy when powered on, and then by setting up a plurality of fixed beds in parallel, the fluid working medium after internal heating of the fluidized bed is transmitted to each fixed bed for heat storage, thereby realizing rapid heat storage of the fluidized bed and the fixed bed, improving the heat storage density, and storing heat through a plurality of fixed beds, which can also avoid the disadvantage of the fluidized bed being too large when using the fluidized bed for heat storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0029] Figure 1aIt is a structural schematic diagram of a thermal energy storage system based on a multi-stage particle packed bed provided by one embodiment of the present invention;

[0030] Figure 1b This is a schematic diagram of a fixed bed heat storage provided by one embodiment of the present invention;

[0031] Figure 1c is a schematic diagram of fluidized bed filling provided by one embodiment of the present invention;

[0032] Figure 2 It is a structural schematic diagram of another thermal energy storage system based on a multi-stage particle packed bed provided by an embodiment of the present invention;

[0033] Figure 3 It is a flow chart of the steps of another thermal energy storage method based on a multi-stage particle packed bed provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Reference Figure 1a , showing a schematic structural diagram of a thermal energy storage system based on a multi-stage particle packed bed provided by an embodiment of the present invention. The thermal energy storage system 100 may include an electric heating module 101, a fluidized bed thermal energy storage module 102 and a fixed bed thermal energy storage module 103, the fluidized bed thermal energy storage module 102 may include a fluidized bed, first particles filled in the fluidized bed cavity, the electric heating module is partially placed inside the fluidized bed cavity and in contact with the first particles, the fixed bed thermal energy storage module is connected to the fluidized bed thermal energy storage module, and the fixed bed thermal energy storage module includes a plurality of parallel fixed beds and second particles filled in the fixed beds.

[0036] In the embodiment of the present invention, the fluidized bed thermal energy storage module 102 and the fixed bed thermal energy storage module 103 are connected via a circulation pipeline, and a fluid medium flows through the circulation pipeline between the fluidized bed thermal energy storage module 102 and the fixed bed thermal energy storage module 103 .

[0037] In an embodiment of the present invention, the first particle and the second particle may be heat storage particle materials. The first particle and the second particle may be selected to have heat storage particle materials with different physical and chemical properties according to the application of the thermal energy storage system in different scenarios. The first particle and the second particle have the characteristic of high temperature resistance (>1000°C). The first particle and the second particle may be sensible heat materials, such as foam ceramics, or latent heat (phase change) materials, such as phase change heat storage particles.

[0038] In the embodiment of the present invention, multiple fixed beds can be provided, and the second particles filled in each fixed bed can be particles of the same material or different materials. For example, the second particles can specifically be any one or more of phase change heat storage particles, microporous materials, and micro-through-hole fixed materials.

[0039] In the embodiment of the present invention, particles are filled in the fluidized bed and the fixed bed, and then the intermediate heat storage medium exchanges heat with the first particles in the fluidized bed, and exchanges heat with the second particles in the fixed bed to achieve the transfer of heat energy, wherein the intermediate heat storage medium can be a fluid working medium, which is in a fluid state in the entire thermal energy storage system to facilitate the movement of thermal energy. The fluid working medium in the embodiment of the present invention can be selected according to the architecture of the thermal energy storage system, the materials of the first particles and the second particles, and the fluid working medium in the embodiment of the present invention can be any one of an inert gas and air.

[0040] In one embodiment of the present invention, the fluidized bed is wrapped with an insulating shell, which is composed of a refractory material layer and an outer insulation layer; heat exchange between the fluidized bed and the outside is avoided, the insulation effect is improved, and thus the heat storage efficiency is improved.

[0041] In the embodiment of the present invention, the electric heating module 101 can be used to heat the first particles when powered on; specifically, the electric heating module 101 can use resistance heating, and the heating wire with resistance is in direct contact with the first particles in the fluidized bed.

[0042] In one embodiment of the present invention, the electric energy of the electric heating module 101 can come from the electric energy generated by the conversion of renewable energy such as light energy and wind energy; the electric energy of the electric heating module 101 can also come from valley electricity. Through the embodiment of the present invention, the electric energy can be converted into thermal energy for storage, and when electricity is needed, the stored thermal energy can be converted into electric energy.

[0043] In the embodiment of the present invention, the fluidized bed thermal energy storage module 102 can be used to exchange heat energy between the heated first particles and the fluid working medium introduced into the fluidized bed chamber, and output the fluid working medium to the fixed bed thermal energy storage module;

[0044] The first particles are electrically heated by the electric heating module in the fluidized bed to collect heat energy. When a fluid working medium is introduced into the fluidized bed, there is a temperature difference between the first particles and the fluid working medium, and heat energy exchange is performed in the fluidized bed, so that the fluid working medium can carry part of the heat energy out of the fluidized bed. The fluid working medium can be transported to the fixed bed of the fixed bed thermal energy storage module through a circulation pipeline to realize energy storage in the fixed bed.

[0045] In an embodiment of the present invention, the fixed bed thermal energy storage module is used to receive the heated fluid output by the fluidized bed, and use the fluid to exchange heat with the second particles in the fixed bed to store thermal energy in the second particles of the fixed bed.

[0046] In one embodiment of the present invention, the thermal energy storage system also includes a water heating pipe module 104; the water heating pipe module is partially placed on the upper part of the fluidized bed cavity and contacts the third particles filled in the upper part of the fluidized bed cavity, and the electric heating module contacts the third particles filled in the lower part of the fluidized bed cavity, wherein the fixed bed thermal energy storage module can be used to use the heat stored in the second particles to heat the fluid working medium passed into the fixed bed, and output the heated fluid working medium to the fluidized bed thermal energy storage module; the fluidized bed thermal energy storage module can be used to pass the fluid working medium after heat exchange with the second particles in the fixed bed, and exchange heat energy between the fluid working medium and the third particles, and use the third particles to heat the water passed into the water heating pipe module.

[0047] The water heating pipe module in the embodiment of the present invention is used to convert thermal energy into electrical energy or directly apply the stored thermal energy. In the fluidized bed, the cavity can be divided into an upper cavity and a lower cavity, a water heating pipe module is arranged in the upper cavity, and an electric heating module is arranged in the lower cavity. The upper part of the fluidized bed cavity can be filled with a third particle, and the third particle can be a heat storage particle material with high temperature resistance (>1000°C). The third particle can be selected according to the application of the thermal energy storage system in different scenarios. The heat storage particle material with different physical and chemical properties. The third particle can be the same as the first particle or different from the first particle.

[0048] When the thermal energy storage system is in a heat release state, the fixed bed heats the fluid medium and then transports it to the fluidized bed. The fluid medium exchanges heat with the first particles and the third particles in the fluidized bed in turn, and then heats the water in the water supply pipe during the heat exchange process with the third particles, so that cold water can be heated to generate hot water, and then hot water can be supplied. When the temperature is high, the water in the water supply pipe can be quickly converted into water vapor, and then the water vapor can be used for heating supply, and can also be used for steam power generation to achieve the conversion of thermal energy into electrical energy.

[0049] In one embodiment of the present invention, the structure of the fluidized bed is that the diameter of the top cylinder is 1.5 to 3 times greater than the inner diameter of the bottom cylinder of the fluidized bed.

[0050] In one embodiment of the present invention, the thermal energy storage system includes an air supply module 105, which is composed of a fan and an air supply pipeline; the fan can be used to transport fluid to the fluidized bed through the air supply pipeline connected to the fluidized bed thermal energy storage module when the electric heating module heats the air medium and the fixed bed thermal energy storage module is in the heat storage stage; and when the fixed bed thermal energy storage module is in the heat release stage, the fluid is transported to each fixed bed in parallel through the air supply pipeline connected to the fixed bed thermal energy storage module.

[0051] In the embodiment of the present invention, the fluid working medium may be air, and the air supply pipeline in the air supply module 105 (i.e., the intermediate circulation pipeline in the embodiment of the present invention) may be the first pipeline (such as the upper pipeline in FIG. 1 ) and the second pipeline (such as the lower pipeline in FIG. 1 ) of the fluidized bed thermal energy storage module and the fixed bed thermal energy storage module, and a third pipeline connecting the first pipeline and the second pipeline. A fan is arranged on the third pipeline.

[0052] The fan is in an on state when the electric heating module heats the air medium and the fixed bed thermal energy storage module is in the heat storage stage, thereby realizing the delivery of fluid working medium to the fluidized bed through the air supply pipeline (i.e., the third pipeline and the second pipeline) connected to the fluidized bed thermal energy storage module. Specifically, the valve between the third pipeline and the second pipeline can be opened, and the fan can be turned on, so that the fan supplies air to the fluidized bed.

[0053] When the fixed bed thermal energy storage module is in the heat release stage, the fan is in an open state, thereby realizing the delivery of fluid working medium to the fixed bed through the air supply pipeline (i.e., the third pipeline and the first pipeline) connected to the fluidized bed thermal energy storage module. Specifically, the valve between the third pipeline and the first pipeline can be opened, and the fan can be turned on, so that the fan supplies air to the fixed bed, and then the fluid working medium is heated in the fixed bed and then output to the fluidized bed for heat release.

[0054] In the embodiment of the present invention, the air supply module 105 may further include a flow meter for measuring the flow rate of the fluid in the air supply pipeline.

[0055] In one embodiment of the present invention, the thermal energy storage system is used to control the fan to be in an off state and close the inlet and outlet of the fluidized bed thermal energy storage module and the fixed bed thermal energy storage module after each fixed bed is heated to a target temperature.

[0056] In one embodiment of the present invention, valves are provided between adjacent fixed beds; the fixed bed thermal energy storage module is used to control the valves between the fixed beds during the heat storage stage so that the heated fluid working medium is sequentially introduced into the multiple fixed beds in a series manner.

[0057] In practical applications, each fixed bed may be provided with valves at the upper and lower parts, respectively. The valves may be used to control the delivery path of the fluid working medium, so that the plurality of fixed beds may be connected in parallel or in series by controlling the valve switches.

[0058] In the heat storage stage, the valves of the fixed beds can be controlled to connect the fixed beds in series for heat storage. The fluid flows through multiple fixed beds in sequence, and heat is exchanged in the fixed beds in sequence before being output, thus realizing step heating.

[0059] In one embodiment of the present invention, two fixed beds (such as two adjacent fixed beds) can be connected in series each time, one of which is a charging bed and the other is a preheating bed, the charging bed is a fixed bed connected to the fluid working medium input port, and the preheating bed is a fixed bed connected to the fluid working medium output port. After the fluid working medium is input into the charging bed, it fully contacts with the second particles in the charging bed, stores heat in the charging bed, and then enters the preheating bed to store the remaining heat in the preheating bed, and outputs the fixed bed after the heat exchange is completed.

[0060] When the temperature of the hot bed becomes stable and the fixed bed is fully stored with heat energy, the fixed bed can be closed, the fluid input port can be connected to the previous preheating bed, and a new preheating bed can be selected from the remaining fixed beds for series connection, and the above energy storage process can be repeated. Figure 1b As shown, it is a schematic diagram of a fixed bed series heating process in an embodiment of the present invention.

[0061] In one embodiment of the present invention, the fixed bed thermal energy storage module is used to control valves of adjacent fixed beds during the heat release stage to sequentially introduce fluid into each fixed bed connected in parallel for heating.

[0062] During the heat release stage, the valves on the upper and lower parts of multiple fixed beds can be opened at the same time, so that the multiple fixed beds are connected in parallel through the circulation pipeline. When the fan is started, the fluid working medium can be simultaneously input into the multiple fixed beds from the upper part. After being heated in the fixed bed, it enters the fluidized bed from the lower part along the air supply pipeline (such as the second pipeline) to achieve rapid heat release.

[0063] In one embodiment of the present invention, the fluidized bed thermal energy storage module also includes an air distribution plate in the fluidized bed. The air distribution plate is used to distribute air evenly to avoid local overheating in the fluidized bed. When the first particles and the third particles are the same type of particles, an air distribution plate is provided at the bottom of the fluidized bed, and the first particles are filled on the air distribution plate; when the first particles and the third particles are different types of particles, a first air distribution plate is provided at the bottom of the fluidized bed, and the two types of particles can be mixed and have inconsistent sizes, and the air distribution plate only needs to ensure that small particles do not leak; a second air distribution plate is provided between the water heating pipe module and the electric heating module, and the third particles are filled on the second air distribution plate.

[0064] In one embodiment of the present invention, the middle of the cavity between the upper part of the cavity and the lower part of the cavity of the fluidized bed heat storage device is fixedly filled with fourth particles for temperature control. The fourth particles are in a fixed state during the operation of the thermal energy storage system. Specifically, the fourth particles can be large-diameter energy storage particles. The fourth particles can be fixed in the fluidized bed by a device or during the operation of the thermal energy storage system, the fluid gas velocity does not reach the minimum fluidization velocity of the fourth particles, so that the fourth particles can be fixed in the fluidized bed for heat storage.

[0065] In practical applications, the fluidized bed can be set to a multi-layer filling structure to stabilize the temperature of the fluid working medium output from the fluidized bed. In the fluidized bed cavity, a water heating pipeline module 104 can be set at the upper part to fill the third particles, and the middle part to fill the fourth particles; an electric heating module can be set at the lower part to fill the first particles; Figure 1c FIG. 1 is a schematic diagram of a fluidized bed structure in an embodiment of the present invention.

[0066] Among them, the fourth particles are heat storage particle materials and can be the same as the second particles.

[0067] In the embodiment of the present invention, the electric heating module converts electrical energy into thermal energy when powered on, and then multiple fixed beds are arranged in parallel. The fluid working medium after internal heating of the fluidized bed is transmitted to each fixed bed for heat storage, thereby realizing rapid heat storage of the fluidized bed and the fixed bed, improving the heat storage density, and storing heat through multiple fixed beds, which can also avoid the disadvantage of the fluidized bed being too large when using the fluidized bed for heat storage.

[0068] Reference Figure 2 This is a schematic diagram of the structure of a thermal energy storage system in an embodiment of the present invention. The thermal energy storage system consists of a fluidized bed and four fixed beds. The upper heating pipe in the fluidized bed is filled with water, and the lower electric heating wire is used for resistance heating. The fluidized bed is filled with heat storage particles, and the fixed bed is filled with phase change heat storage particles.

[0069] Thermal energy storage systems can exist in three states: heat storage stage, storage stage, and heat release stage.

[0070] (i) When the thermal energy storage system is in the heat storage stage, the fan is turned on, the upper valve of the third pipeline is closed, and the lower valve is opened. The fan supplies air to the fluidized bed through the pipeline. The heat provided by the electric heating device in the fluidized bed heats the first particles in the bed, and quickly transfers a large amount of heat to the air working medium, and further transfers it to the fixed bed thermal energy storage module until all fixed beds are heated to the target temperature.

[0071] Among them, the heat-carrying air medium flowing out of the fluidized bed can adopt a step-by-step series heating method when heating multiple parallel fixed beds; the step-by-step series heating method is specifically as follows: during heating, the heat-carrying air medium is sequentially passed through two adjacent fixed beds in series, and then the residual hot air is directly discharged; the first fixed bed of the two adjacent fixed beds is called a charging bed, and the second fixed bed of the two adjacent fixed beds is called a preheating bed. When the temperature of the first fixed bed (i.e., the charging bed) is heated to the target temperature, the heat-carrying air medium inlet is switched to the second fixed bed (i.e., the preheating bed), and the air outlet of the preheating bed is switched to the inlet of the next fixed bed; the two adjacent fixed beds that are further heated form a new combination of a charging bed and a preheating bed; and the heating is performed in a progressive manner until the temperature of the fixed beds reaches the target temperature.

[0072] (ii) When the thermal energy storage system is in the storage stage, the air supply module is cut off, and the inlet and outlet of the fluidized bed thermal energy storage module and the fixed bed thermal energy storage module are closed, so that the entire device system is in a constant temperature maintenance state.

[0073] (III) When the thermal energy storage system is in the heat release stage, the fan is turned on, the upper valve of the third pipeline is opened, and the lower valve is closed. The fan supplies air to the fixed bed through the pipeline. After being heated in the fixed bed, the heat-carrying air working medium is transported to the fluidized bed through the pipeline, and stable heat energy is released in the fluidized bed. The water in the heating module can be heated by the released heat energy, and hot water or water vapor is output. The water vapor can be used to convert heat energy into electrical energy in the steam power generation device.

[0074] When releasing heat, the multiple fixed beds may release heat in parallel, that is, each fixed bed releases heat in turn.

[0075] Reference Figure 3 , showing a step flow chart of another thermal energy storage method based on a multi-stage particle packed bed provided by an embodiment of the present invention, which is applied to a thermal energy storage system, wherein the thermal energy storage system includes an electric heating module, a fluidized bed thermal energy storage module and a fixed bed thermal energy storage module, the fluidized bed thermal energy storage module includes a fluidized bed, first particles filled in the fluidized bed cavity, the electric heating module is partially placed inside the fluidized bed cavity and in contact with the first particles, the fixed bed thermal energy storage module is connected to the fluidized bed thermal energy storage module, and the fixed bed thermal energy storage module includes a plurality of parallel fixed beds and second particles filled in the fixed beds.

[0076] In an embodiment of the present invention, in the energy storage stage, the electric heating module can be used to heat the first particles in a power-on state; the fluidized bed thermal energy storage module can be used to exchange heat energy between the heated first particles and the fluid working medium introduced into the fluidized bed chamber, and output the fluid working medium to the fixed bed thermal energy storage module; the fixed bed thermal energy storage module can be used to receive the heated fluid working medium output by the fluidized bed, and use the fluid working medium to exchange heat with the second particles in the fixed bed to store heat energy in the second particles of the fixed bed.

[0077] Therefore, the thermal energy storage method based on the thermal energy storage system in the embodiment of the present invention may specifically include the following steps:

[0078] Step 301, heating the first particles in a power-on state;

[0079] In practical applications, the electric heating module is powered on to convert electrical energy into thermal energy, thereby heating the first particles.

[0080] Step 302, the heated first particles exchange heat energy with the fluid medium introduced into the fluidized bed chamber, and the fluid medium is output to the fixed bed of the fixed bed thermal energy storage module;

[0081] After the first particles in the fluidized bed are heated, a fluid medium can be introduced, and the fluid medium exchanges heat energy with the first particles to heat the fluid medium. The heated fluid medium is transported along the pipeline to the fixed bed.

[0082] Step 303: Use the fluid working medium to perform heat exchange with the second particles in the fixed bed to store heat energy in the second particles in the fixed bed.

[0083] The fixed bed is filled with second particles, which are heat storage materials. The heat energy can be stored in the second particles through full contact between the second particles and the heating fluid.

[0084] In one embodiment of the present invention, the thermal energy storage system can realize both heat storage and heat release. Steps 301 to 303 are performed in the heat storage stage, and the steps in the heat release stage are as follows:

[0085] Step 304, using the heat stored in the second particles to heat the fluid medium passing into the fixed bed, and outputting the heated fluid medium to the fluidized bed thermal energy storage module;

[0086] In the heat release stage, the fluid medium flows through the fixed bed, the second particles in the fixed bed exchange heat with the fluid medium, and the fluid medium carrying heat is transported to the fluidized bed.

[0087] Step 305 , in the fluidized bed of the fluidized bed thermal energy storage module, the fluid working medium exchanges heat energy with third particles filled in the fluidized bed, and the third particles are used to heat water introduced into the water heating pipeline module.

[0088] The water introduced into the water heating pipe module is heated during the heat exchange process in the fluidized bed, and the cold water is heated into hot water or water vapor is generated. Then, the hot water or water vapor can be used. For example, the generated hot water or water vapor can be used for hot water or heating supply. The water vapor can also use a steam power generation device to realize the conversion between thermal energy and electrical energy.

[0089] In an embodiment of the present invention, the first particles are heated in a power-on state; the heated first particles exchange heat energy with the fluid working medium introduced into the fluidized bed chamber, and the fluid working medium is output to the fixed bed of the fixed bed thermal energy storage module; the fluid working medium is used to exchange heat with the second particles in the fixed bed to store heat energy in the second particles in the fixed bed, thereby achieving rapid heat storage of the fluidized bed and the fixed bed, improving the heat storage density, and storing heat through multiple fixed beds, which can also avoid the disadvantage of the fluidized bed being too large when using the fluidized bed for heat storage.

[0090] It should be noted that, for the sake of simplicity, the method embodiments are described as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0091] An embodiment of the present invention further provides an electronic device, which may include a processor, a memory, and a computer program stored in the memory and capable of running on the processor. When the computer program is executed by the processor, the above-mentioned thermal energy storage method based on a multi-stage particle packed bed is implemented.

[0092] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the thermal energy storage method based on a multi-stage particle packed bed as described above is implemented.

[0093] Since the system and method embodiments are basically similar, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0094] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0095] Those skilled in the art will appreciate that the embodiments of the present invention may be provided as methods, devices, or computer program products. Therefore, the embodiments of the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the embodiments of the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0096] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate a device for implementing the functions specified in one process or multiple processes in the flowchart and / or one box or multiple boxes in the block diagram.

[0097] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0098] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce computer-implemented processing, so that the instructions executed on the computer or other programmable terminal device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0099] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0100] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0101] The above is a detailed introduction to a thermal energy storage method and system based on a multi-stage particle packed bed. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A thermal energy storage system based on a multi-stage particle packed bed, characterized in that: The thermal energy storage system comprises an electric heating module, a fluidized bed thermal energy storage module and a fixed bed thermal energy storage module, wherein the fluidized bed thermal energy storage module comprises a fluidized bed and first particles filled in a cavity of the fluidized bed, wherein a portion of the electric heating module is disposed inside the cavity of the fluidized bed and in contact with the first particles, and the fixed bed thermal energy storage module is connected to the fluidized bed thermal energy storage module, and the fixed bed thermal energy storage module comprises a plurality of fixed beds connected in parallel and second particles filled in the fixed beds; The electric heating module is used to heat the first particles when powered on; The fluidized bed thermal energy storage module is used to exchange heat energy between the heated first particles and the fluid working medium introduced into the fluidized bed chamber, and output the fluid working medium to the fixed bed thermal energy storage module; The fixed bed thermal energy storage module is used to receive the heated fluid medium output by the fluidized bed, and use the fluid medium to perform heat exchange with the second particles in the fixed bed to store thermal energy in the second particles of the fixed bed.

2. The thermal energy storage system according to claim 1, characterized in that: The thermal energy storage system further includes a water heating pipeline module; the water heating pipeline module is partially placed on the upper part of the fluidized bed cavity and contacts the third particles filled in the upper part of the fluidized bed cavity, and the electric heating module contacts the first particles filled in the lower part of the fluidized bed cavity; The fixed bed thermal energy storage module is used to heat the fluid medium passing into the fixed bed using the heat stored in the second particles, and output the heated fluid medium to the fluidized bed thermal energy storage module; The fluidized bed thermal energy storage module is used to introduce the fluid medium that has exchanged heat with the second particles in the fixed bed, and to exchange heat energy between the fluid medium and the third particles, and to use the third particles to heat the water introduced into the water heating pipeline module.

3. The thermal energy storage system according to claim 1 or 2, characterized in that: Valves are arranged between adjacent fixed beds; the fixed bed thermal energy storage module is used to control the valves between the fixed beds during the heat storage stage so that the heated fluid working medium is sequentially introduced into the multiple fixed beds in a series connection.

4. The thermal energy storage system according to claim 3, characterized in that: The fixed bed thermal energy storage module is used to control the valves of adjacent fixed beds in the heat release stage to sequentially introduce fluid working medium into each fixed bed connected in parallel for heating.

5. The thermal energy storage system according to claim 2, characterized in that: The middle part of the cavity between the upper part of the cavity and the lower part of the cavity of the fluidized bed heat storage device is fixedly filled with fourth particles for temperature control.

6. The thermal energy storage system according to claim 2, characterized in that: The thermal energy storage system includes an air supply module, which is composed of a fan and an air supply pipeline; The fan is used to transport fluid to the fluidized bed through an air supply pipeline connected to the fluidized bed thermal energy storage module when the electric heating module heats the air medium and the fixed bed thermal energy storage module is in the heat storage stage; and to transport fluid to each fixed bed connected in parallel through an air supply pipeline connected to the fixed bed thermal energy storage module when the fixed bed thermal energy storage module is in the heat release stage.

7. The thermal energy storage system according to claim 6, characterized in that: The thermal energy storage system is used to control the fan to be in an off state and close the inlet and outlet of the fluidized bed thermal energy storage module and the fixed bed thermal energy storage module after each fixed bed is heated to a target temperature.

8. The thermal energy storage system according to claim 6, characterized in that: The fluidized bed thermal energy storage module also includes an air distribution plate in the fluidized bed. When the first particles and the third particles are the same type of particles, an air distribution plate is arranged at the bottom of the fluidized bed. When the first particles and the third particles are different types of particles, a first air distribution plate is arranged at the bottom of the fluidized bed, and a second air distribution plate is arranged between the water heating pipe module and the electric heating module.

9. A thermal energy storage method based on a multi-stage packed bed, characterized in that: Applied to the thermal energy storage system according to any one of claims 1 to 8, the method comprising: heating the first particles in an energized state; The heated first particles exchange heat energy with the fluid medium introduced into the fluidized bed chamber, and output the fluid medium to the fixed bed of the fixed bed thermal energy storage module; The fluid working medium is used to perform heat exchange with the second particles in the fixed bed, so as to store thermal energy in the second particles of the fixed bed.

10. The method according to claim 9, characterized in that The method further comprises: The heat stored in the second particles is used to heat the fluid medium passing into the fixed bed, and the heated fluid medium is output to the fluidized bed thermal energy storage module; In the fluidized bed of the fluidized bed thermal energy storage module, the fluid working medium exchanges heat energy with third particles filled in the fluidized bed, and the third particles are used to heat water introduced into the water heating pipeline module.

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