Molten salt heat storage and release method and system

Abstract

The embodiment of the invention provides a molten salt heat storage and release method and system, the molten salt heat storage and release system comprises a fluidized bed reactor and an electric heating module partially arranged in the fluidized bed reactor, the heat extraction tube bundle is arranged in the fluidized bed reactor, the hot salt tank and the cold salt tank are used for storing a molten salt medium, the circulating pipeline is used for transporting the molten salt medium, and the steam generation module is connected between the hot salt tank and the cold salt tank; the fluidized bed reactor is filled with heat carrier particles for storing heat; an outlet of the cold salt tank is connected with an inlet of the heat removal tube bundle through the circulating pipeline, and an inlet of the hot salt tank is connected with an outlet of the heat removal tube bundle through the circulating pipeline. According to the embodiment of the invention, complementary heat storage of the fluidized bed and the molten salt tank is realized, and the small molten salt tank is used as a bridge, so that heat can be released stably and controllably.

Description

Technical Field

[0001] The present invention relates to the field of heat storage technology, and in particular to a molten salt heat storage and release method and a molten salt heat storage and release system. Background Art

[0002] Relying on new low-carbon energy is a long-term solution to meet the global economic development and related energy demand growth. Accelerating the development and utilization of renewable energy and developing high-efficiency solar energy and large-scale wind power technologies are the key to achieving a successful transition to a low-carbon energy system. However, due to the intermittent and unpredictable nature of wind power and solar photovoltaic power generation, opportunities and challenges for energy storage have emerged. Among the many energy storage technologies, thermal storage technology uses thermal storage materials as a medium to store thermal energy such as solar thermal energy, geothermal energy, industrial waste heat, and low-grade waste heat, solving the intermittent and unstable shortcomings of renewable energy and the contradiction between the mismatch of supply and demand in time and space during energy conversion and utilization, so as to improve the utilization rate of thermal energy.

[0003] Currently in the field of heat storage, fixed heat storage methods represented by solid materials such as sand, concrete, and cast ceramics have the advantages of low cost, high strength, and easy processing and molding. However, this type of sensible heat storage material has a low heat storage density, so the equipment is bulky in industrial applications, and it is difficult to achieve constant temperature control during the heat release process. Summary of the invention

[0004] In view of the above problems, a molten salt heat storage and release method and system are proposed to overcome the above problems or at least partially solve the above problems, including:

[0005] A molten salt heat storage and release system, the molten salt heat storage and release system comprising a fluidized bed reactor, an electric heating module partially placed in the fluidized bed reactor, a heat extraction tube bundle placed in the fluidized bed reactor, a hot salt tank and a cold salt tank for storing molten salt medium, a circulation pipeline for transporting the molten salt medium, and a steam generation module connected between the hot salt tank and the cold salt tank; the fluidized bed reactor is filled with heat carrier particles for storing heat; the outlet of the cold salt tank is connected to the inlet of the heat extraction tube bundle through the circulation pipeline, and the inlet of the hot salt tank is connected to the outlet of the heat extraction tube bundle through the circulation pipeline;

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

[0007] The cold salt tank is used to transport the molten salt medium to the heat extraction tube bundle through the circulation pipeline;

[0008] The fluidized bed reactor is used to exchange heat between the heated heat carrier particles and the molten salt medium introduced into the inlet of the heat extraction tube bundle, and transport the heated molten salt medium to the hot salt tank through the outlet of the heat extraction tube bundle;

[0009] The hot salt tank is used to transport the molten salt medium to the steam generation module through a circulation pipeline;

[0010] The steam generation module is used to heat the water entering the steam generation module using the molten salt medium input from the hot salt tank to generate steam.

[0011] Optionally, the molten salt heat storage and release system also includes an air supply module connected to the bottom of the fluidized bed reactor and used to supply air to the fluidized bed reactor. The bottom of the fluidized bed reactor is provided with a high-temperature resistant air distribution plate or is piled with high-temperature resistant particles, which are used to uniformly distribute the air entering the fluidized bed reactor; the top of the fluidized bed reactor is provided with an air supply outlet, and the air supply outlet is connected to the air supply module outside the fluidized bed reactor and is connected to a cyclone separator inside the fluidized bed reactor. The cyclone separator is used to separate the heat carrier particles carried in the wind.

[0012] Optionally, the steam generating module includes a water pipeline, water flows through the water pipeline, and the portion of the water pipeline before the molten salt medium in the hot salt tank is heated is connected to the air supply outlet, so that the hot air in the fluidized bed reactor contacts the water pipeline through the air supply outlet to preheat the water in the output pipeline.

[0013] Optionally, a pump is provided on the circulation pipeline between the cold salt tank and the fluidized bed reactor, and the pump is used to control the cold salt tank to transport the molten salt medium to the heat extraction tube bundle in the fluidized bed reactor through the circulation pipeline.

[0014] Optionally, the steam generation module is connected to a steam power generation module, and the steam power generation module is used to receive the steam generated by the steam generation module and use the steam to generate electrical energy.

[0015] Optionally, the melting point of the heat carrier particles is higher than 1500° C., the particle size of the heat carrier particles is in the range of 0-500 μm; and the particle size of the high temperature resistant particles is in the range of 1 mm to 30 mm.

[0016] Optionally, the heating method of the electric heating module includes any one of the following:

[0017] Graphite electrode heating, silicon-molybdenum heating, infrared heating.

[0018] Optionally, the heat extraction tube bundle is a shell-and-tube or serpentine heat exchange tube.

[0019] Optionally, the molten salt heat storage and release system includes a thermal insulation layer arranged outside or inside the shell of the fluidized bed reactor, and the thermal insulation layer is used to insulate and heat the fluidized bed reactor.

[0020] A molten salt heat storage and release method, applied to the thermal energy storage system as described in any one of the above items, the method comprising:

[0021] In a power-on state, the electric heating module is used to heat the heat carrier particles;

[0022] Transporting the molten salt medium in the cold salt tank to the heat extraction tube bundle through the circulation pipeline;

[0023] In the fluidized bed reactor, the heated heat carrier particles are heat exchanged with the molten salt medium introduced into the inlet of the heat extraction tube bundle, and the heated molten salt medium is transported to the hot salt tank through the outlet of the heat extraction tube bundle;

[0024] transporting the molten salt medium stored in the hot salt tank to the steam generation module through a circulation pipeline;

[0025] The molten salt medium input from the hot salt tank is used to heat the water entering the steam generation module to generate steam.

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

[0027] In the embodiment of the present invention, a fluidized bed reactor, a hot salt tank and a cold salt tank are combined to store or release heat, and the fluidized bed and the molten salt tank are used to store heat complementary to each other, and a small molten salt tank is used as a bridge to enable the heat to be released stably and controllably. 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 1a It is a structural schematic diagram of a molten salt heat storage and release system provided by one embodiment of the present invention;

[0030] Figure 1b It is a structural schematic diagram of another molten salt heat storage and release system provided by one embodiment of the present invention;

[0031] Figure 2 It is a structural schematic diagram of another molten salt heat storage and release system provided by one embodiment of the present invention;

[0032] Figure 3 It is a flow chart of the steps of another molten salt heat storage and release method provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0033] 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.

[0034] Reference Figure 1a , showing a schematic structural diagram of a molten salt heat storage and release system provided by an embodiment of the present invention; the molten salt heat storage and release system comprises a fluidized bed reactor 101, an electric heating module 102 partially disposed in the fluidized bed reactor, and a heat extraction tube bundle 103 disposed in the fluidized bed reactor, a hot salt tank 104 and a cold salt tank 105 for storing molten salt medium, a circulation pipeline 106 for transporting the molten salt medium, and a steam generation module 107 connected between the hot salt tank and the cold salt tank; the fluidized bed reactor is filled with heat carrier particles for storing heat; the outlet of the cold salt tank is connected to the inlet of the heat extraction tube bundle through the circulation pipeline, and the inlet of the hot salt tank is connected to the outlet of the heat extraction tube bundle through the circulation pipeline;

[0035] In one embodiment of the present invention, the heat carrier particles in the fluidized bed reactor wrap the heat extraction tube bundle in the inner cavity of the fluidized bed reactor to facilitate the exchange of heat energy with the medium passing through the heat extraction tube bundle. The heat carrier particles in the fluidized bed reactor include the heat-generating part of the electric heating module in the inner cavity of the fluidized bed reactor, so that the electric heating module can be used to heat the heat carrier particles in the fluidized bed reactor.

[0036] The heat carrier particles are heat storage particles made of high temperature resistant materials. Specifically, the melting point of the heat carrier particles is higher than 1500°C. For example, the heat carrier particles can be made of graphite particles. Based on the high melting point property of the heat carrier particles, the heat carrier particles can be ensured to maintain a granular shape during the heat storage and heat release process of the molten salt heat storage and release system.

[0037] In an embodiment of the present invention, the particle size range of the heat carrier particles is 0μm to 500μm, including 500μm. Preferably, the particle size range of the heat carrier particles may be 100μm to 300μm, including 100μm and 300μm. More preferably, the particle size range of the heat carrier particles may be 150μm to 200μm, including 150μm and 200μm.

[0038] In an embodiment of the present invention, the cold salt tank stores cold molten salt medium, and the hot salt tank stores heated storage medium. The cold molten salt medium is transported from the cold salt tank to the heat extraction tube bundle through a circulation pipeline, and is transported to the hot salt tank for storage after heat exchange with heated heat carrier particles in the fluidized bed reactor. When there is a need to release heat, the hot salt tank outputs the heated molten salt medium, which is returned to the cold salt tank through a circulation pipeline after heat exchange with water in the steam generating module, thereby realizing the circulation transportation of the molten salt medium, thereby enabling the entire molten salt heat storage and release system to cyclically and continuously store and release heat.

[0039] In the embodiment of the present invention, the cold salt tank and the hot salt tank can be small tanks, so as to realize constant temperature control during the heat release process.

[0040] In one embodiment of the present invention, in order to improve the heat storage efficiency, the heat extraction tube bundle may be configured as a tube-in-tube or serpentine heat exchange tube to increase the contact area between the heat extraction tube bundle and the heat carrier particles filled in the fluidized bed reactor.

[0041] Specifically, the functions of each module of the molten salt heat storage and release system in the embodiment of the present invention are as follows:

[0042] The electric heating module can be used to heat the heat carrier particles when powered on; converting electrical energy into thermal energy. In one example, the electric heating module can implement electric heating by any of the following electric heating methods: graphite electrode heating, silicon-molybdenum heating, and infrared heating.

[0043] The electric energy in the embodiment of the present invention can come from valley electricity or renewable energy. For example, wind energy or light energy can be converted into electric energy, and the generated electric energy can be applied to an electric heating module to realize the conversion of electric energy into thermal energy.

[0044] When the electric heating module is powered on, the electrical energy is converted into thermal energy, and the thermal energy can heat the heat carrier particles in the fluidized bed reactor cavity, so that the heat carrier particles carry thermal energy.

[0045] In one embodiment of the present invention, the electric heating module may be replaced by a heat generating module, for example, a photothermal or wind thermal module, that is, a module that converts light energy into heat or wind energy into heat.

[0046] The cold salt tank in the embodiment of the present invention can be used to store molten salt medium. When the heat storage system needs to store heat, the molten salt medium stored in the cold salt tank can be transported to the heat extraction tube bundle through the circulation pipeline to heat the molten salt medium in the fluidized bed reactor.

[0047] In an embodiment of the present invention, the heat extraction tube bundle includes an inlet and an outlet, the inlet of the heat extraction tube bundle is connected to the cold salt tank through a circulation pipeline, the outlet of the heat extraction tube bundle is connected to the hot salt tank through a circulation pipeline, and the molten salt medium enters the fluidized bed reactor from the inlet of the heat extraction tube bundle and flows out of the fluidized bed reactor from the outlet of the heat extraction tube bundle. The fluidized bed reactor can be used to exchange heat between the heated heat carrier particles and the molten salt medium introduced into the inlet of the heat extraction tube bundle, that is, to transfer the heat energy carried by the heat carrier particles to the molten salt medium, and then transport the heated molten salt medium from the outlet of the heat extraction tube bundle to the hot salt tank through the circulation pipeline to achieve heat storage.

[0048] In an embodiment of the present invention, the hot salt tank can be used to store molten salt medium that carries heat, and when the molten salt heat storage and release system needs to release heat, the molten salt medium that carries heat can be transported to the steam generation module through a circulation pipeline to generate steam.

[0049] In an embodiment of the present invention, the steam generating module is a module for generating steam. Specifically, the steam generating pipeline may include a water pipeline for conveying water. The molten salt medium input from the hot salt tank may be used in the steam generating module to heat the water in the water pipeline to generate steam, which is then used.

[0050] In one example, steam can be used for heating; in another embodiment, steam can be used to realize steam power generation to convert thermal energy into electrical energy. Specifically, the steam generation module is connected to the steam power generation module, and the steam power generation module is used to receive the steam generated by the steam generation module and use the steam to generate electrical energy.

[0051] In one embodiment of the present invention, the molten salt heat storage and release system may include a heat insulation layer disposed outside or inside the shell of the fluidized bed reactor, and the heat insulation layer is used to insulate the fluidized bed reactor to avoid heat exchange between the fluidized bed reactor and the external environment, so as to further improve the heat storage efficiency of the molten salt heat storage and release system.

[0052] In one embodiment of the present invention, the molten salt heat storage and release system may further include an air supply module 108 connected to the bottom of the fluidized bed reactor for supplying air to the fluidized bed reactor. The air supply module may control the wind speed to achieve fluidization control of the heat carrier particles filled and in the fluidized bed reactor, thereby controlling the heat exchange. A high temperature resistant air distribution plate or high temperature resistant particles may also be provided at the bottom of the fluidized bed reactor to evenly distribute the air entering the fluidized bed reactor; uneven temperature distribution in the fluidized bed may be avoided by evenly distributing the air. Among them, the particle size range of the high temperature resistant particles is 1mm to 30mm. The specific types of high temperature resistant air distribution plates and high temperature resistant particles can be set according to the characteristics of the molten salt heat storage and release system under the working state. In the embodiment of the present invention, there is no excessive restriction on this. At least, in the molten salt heat storage and release system in the embodiment of the present invention, the high temperature resistant air distribution plates and high temperature resistant particles can ensure that their melting points are higher than the maximum temperature during operation to avoid morphological changes during operation.

[0053] In one embodiment of the present invention, an air supply outlet is provided at the top of the fluidized bed reactor, and the air supply outlet is connected to the air supply module outside the fluidized bed reactor, so that the wind from the air supply module flows into the fluidized bed from the bottom, and then flows back to the air supply module from the top air supply outlet, thereby realizing air circulation.

[0054] The air supply module 108 may include a fan 11 and an air preheater 12. The air preheater may heat the air generated by the fan, and then input the heated air into the fluidized bed reactor for heat exchange.

[0055] In one embodiment of the present invention, in order to prevent the wind from carrying the heat carrier particles filled in the fluidized bed reactor out of the fluidized bed reactor, the air supply outlet can be connected to a cyclone separator 109 inside the fluidized bed reactor. The cyclone separator is used to separate the heat carrier particles carried in the wind. When the heat carrier particles carried in the wind enter the cyclone separator, the heat carrier particles settle back into the fluidized bed reactor, and the filtered air is output from the fluidized bed reactor through the air supply outlet.

[0056] In one embodiment of the present invention, after the wind from the air supply module enters the fluidized bed reactor and participates in the fluidization of the heat carrier particles, it may carry some heat. In order to fully utilize the energy, the part of the water pipeline of the steam generation module before the molten salt medium in the hot salt tank is heated can be connected to the air supply outlet, so that the hot air output from the fluidized bed reactor contacts the water pipeline through the air supply outlet, and the water in the output pipeline is preheated. Thus, the water in the water pipeline of the steam generation module is first transported to the air supply outlet for preheating, and then heated by the hot molten salt medium transported in the hot salt tank to generate steam.

[0057] Specifically, the steam generating module 107 includes a condensed water tank 13, a water preheater 14 and a steam generator 15. The condensed water tank 13 provides cold water, which is transported to the water preheater 14 through a water pipe. The water preheater is connected to the air supply outlet of the fluidized bed reactor to preheat the water in the water pipe of the water preheater 15 with hot air. After being heated by the water preheater 14, the water is transported to the steam generator 15 through the water pipe, and the water is heated by a hot molten salt medium to generate steam.

[0058] In one embodiment of the present invention, a pump 109 may be provided on the circulation pipeline between the cold salt tank and the fluidized bed reactor, and the pump is used to control the cold salt tank to transport the molten salt medium to the heat extraction tube bundle in the fluidized bed reactor through the circulation pipeline.

[0059] In one embodiment of the present invention, a temperature detection module can also be set in the molten salt heat storage and release system. The temperature detection module can be used to detect the temperature changes of the heat carrier particles and the molten salt medium in the molten salt heat storage and release system, and determine the current stage of the molten salt heat storage and release system through the temperature changes, while ensuring that during the operation of the molten salt heat storage and release system, the operating temperature of the system does not exceed the normal operating temperature range of the molten salt.

[0060] Specifically, the temperature control module in the embodiment of the present invention can be divided into two parts: (1) fluidized bed temperature control; (2) molten salt medium temperature control.

[0061] Fluidized bed temperature control: Tungsten-rhenium high-temperature resistant thermocouples and infrared thermometers can be used for temperature detection; the monitoring position can be located in the dense phase area of ​​the fluidized bed or monitor the fluidized bed outlet gas (before entering the preheater), such as Figure 1b T1 in.

[0062] Among them, when using thermocouples to detect the fluidized bed temperature: when the monitoring position is in the dense phase zone of the fluidized bed, the thermocouple can be vertically inserted from the top of the fluidized bed into the particle bed layer or the thermocouples can be evenly arranged on the side wall of the fluidized bed to monitor the temperature of the particles in the fluidized bed at the same time; when the monitoring position is at the gas outlet of the fluidized bed, the thermocouple is inserted into the center of the pipeline to measure the outlet gas temperature.

[0063] When an infrared thermometer is used to detect the temperature of the fluidized bed, the infrared thermometer can be placed on the top or side of the fluidized bed, and the temperature of the particles in the fluidized bed can be observed through a specially placed infrared temperature measurement window.

[0064] (2) Molten salt medium temperature: Since the molten salt medium temperature is 400-500°C, any conventional thermocouple on the market can be used; a temperature measuring point 1 (i.e. Figure 1b T1 in the figure), it is necessary to monitor the temperature of the hot molten salt leaving the fluidized bed, and set a temperature measuring point 2 (i.e. Figure 1b T2 in the figure is set to <500℃; a temperature measuring point 3 (i.e. Figure 1b T3 in the figure), set a temperature measuring point 4 (i.e. Figure 1b T4 in the monitoring, the temperature of the cold tank cannot be lower than the freezing point of the molten salt.

[0065] based on Figure 1b The heat storage and release process of the molten salt heat storage and release system is as follows:

[0066] Heat storage stage: When the temperature measuring point 1 detects that the molten salt temperature exceeds the set temperature (such as 480°C) and the hot tank liquid level is low, the molten salt flow can be accelerated; when the hot tank liquid level is high, the molten salt pipeline is closed.

[0067] Monitor the temperature change of the thermocouple or infrared thermometer. When the set maximum temperature is reached, the fluidized bed stops heating.

[0068] Heat release stage: When the temperature monitored by the fluidized bed temperature monitoring point / temperature measurement point 1 is lower than the set temperature, it indicates that the heat release of the molten salt tank and the fluidized bed is complete.

[0069] After the heat is released, the heating module can be turned on again for a new round of heat storage.

[0070] In an embodiment of the present invention, a molten salt heat storage and release system can be set up. The molten salt heat storage and release system may include a fluidized bed reactor, an electric heating module partially placed in the fluidized bed reactor, and a heat extraction tube bundle placed in the fluidized bed reactor, a hot salt tank and a cold salt tank for storing molten salt medium, a circulation pipeline for transporting the molten salt medium, and a steam generating module connected between the hot salt tank and the cold salt tank. Heat storage and heat release are then achieved through the fluidized bed, the hot salt tank and the cold salt tank. The fluidized bed and the molten salt tank complement each other in heat storage; the small molten salt tank acts as a bridge to allow heat to be released in a stable and controllable manner.

[0071] Reference Figure 2 The schematic diagram of the structure of a molten salt heat storage and release system in an embodiment of the present invention is shown in FIG. The molten salt heat storage and release system may include a fluidized bed reactor, a heating electrode group, a heat extraction tube bundle, a cyclone separator, an air supply module, a cyclone separator, a hot salt tank, a cold salt tank, a molten salt pump, a circulation pipeline, a steam generation module, and a steam power generation module, wherein the air supply module may include a fan, an air preheater, and an air supply pipeline; the steam generation module may include a condensate pipe, a feed water preheater, a water pipeline, and a molten salt steam generator; and the steam power generation module includes a temperature reduction and pressure reduction station, a steam turbine, and a generator.

[0072] Among them, the air supply process of the air supply module is as follows: the fan generates wind, which is heated by the air preheater and then input into the fluidized bed reactor from the bottom of the fluidized bed reactor, and participates in the fluidization process of the heat carrier particles in the fluidized bed reactor. After the wind passes through the cyclone separator to settle the heat carrier particles, it is input into the water feed preheater from the top of the fluidized bed reactor, and the heat carried by the wind is transferred to the water in the water supply pipe in the water preheater to preheat the water. After that, the heat exchanged wind returns to the air preheater through the air supply pipe for heating, and then is input into the fluidized bed reactor again.

[0073] The molten salt heat storage and release system involves heat storage process, heat preservation process and heat release process in the heat storage and release process.

[0074] Among them, the heat storage process of the molten salt heat storage and release system is: use an electric heating device and / or a photothermal device to heat the heat carrier particles fluidized by the air, and the heat carrier particles heat the cold molten salt medium transported from the cold salt tank through the circulation pipeline through the heat extraction tube bundle to form a hot molten salt medium, and flow into the hot salt tank through the circulation pipeline for storage. This process can convert electrical energy into thermal energy, and transfer thermal energy, and then store thermal energy in the hot salt tank.

[0075] When the temperature of the molten salt medium reaches the operating temperature of 400℃~500℃, the supply of the heat extraction tube bundle is cut off, and the heat carrier particles are continued to be heated by the electric heating device and / or the photothermal device until the temperature of the heat carrier particles reaches 1000℃~2000℃, completing the "electric energy → thermal energy" process of the molten salt heat storage and release system coupled with the fluidized bed and molten salt.

[0076] The insulation process of the molten salt heat storage and release system is: cutting off the air intake of the fluidized bed and closing the exhaust gas discharge, and the molten salt heat storage and release system coupled with the fluidized bed and molten salt is in the insulation process.

[0077] The heat release process of the molten salt heat storage and release system is as follows: the hot molten salt medium in the hot salt tank in the molten salt heat storage and release system is pumped to the molten salt steam generator to generate steam, and the steam is used for heating or power generation, thereby realizing the "thermal energy → electric energy / thermal energy → thermal energy" process.

[0078] When the hot molten salt medium in the hot salt tank drops to the preset working liquid level, the molten salt pump is turned on to circulate the cold molten salt medium in the cold salt tank to the heat extraction tube bundle sent into the fluidized bed. When the hot molten salt medium is heated, it flows back to the hot salt tank again, and the air supply module is turned on at the same time to control the heat transfer coefficient of the fluidized bed.

[0079] When the temperature of the heat carrier particles in the fluidized bed drops to the temperature of the cold molten salt medium, the "thermal energy → electric energy / thermal energy → thermal energy" process of the molten salt heat storage and release system coupled with the fluidized bed and molten salt is completed.

[0080] Reference Figure 3, showing a flow chart of the steps of a molten salt heat storage and release method provided by an embodiment of the present invention, which is applied to a thermal energy storage system, wherein the molten salt heat storage and release system comprises a fluidized bed reactor, an electric heating module partially placed in the fluidized bed reactor, and a heat extraction tube bundle placed in the fluidized bed reactor, a hot salt tank and a cold salt tank for storing molten salt medium, a circulation pipeline for transporting the molten salt medium, and a steam generation module connected between the hot salt tank and the cold salt tank; the fluidized bed reactor is filled with heat carrier particles for storing heat; the outlet of the cold salt tank is connected to the inlet of the heat extraction tube bundle through the circulation pipeline, and the inlet of the hot salt tank is connected to the outlet of the heat extraction tube bundle through the circulation pipeline;

[0081] The electric heating module is used to heat the heat carrier particles when powered on;

[0082] The cold salt tank is used to transport the molten salt medium to the heat extraction tube bundle through the circulation pipeline;

[0083] The fluidized bed reactor is used to exchange heat between the heated heat carrier particles and the molten salt medium introduced into the inlet of the heat extraction tube bundle, and transport the heated molten salt medium to the hot salt tank through the outlet of the heat extraction tube bundle;

[0084] The hot salt tank is used to transport the molten salt medium to the steam generation module through a circulation pipeline;

[0085] The steam generation module is used to heat the water entering the steam generation module using the molten salt medium input from the hot salt tank to generate steam.

[0086] Based on the above thermal energy storage system, the thermal energy storage method in the embodiment of the present invention may specifically include the following steps:

[0087] Step 301, in a power-on state, using an electric heating module to heat heat carrier particles;

[0088] Step 302, transporting the molten salt medium in the cold salt tank to the heat extraction tube bundle through the circulation pipeline;

[0089] Step 303, in the fluidized bed reactor, the heated heat carrier particles are heat exchanged with the molten salt medium introduced into the inlet of the heat extraction tube bundle, and the heated molten salt medium is transported to the hot salt tank through the outlet of the heat extraction tube bundle;

[0090] Step 304, transporting the molten salt medium stored in the hot salt tank to the steam generation module through a circulation pipeline;

[0091] Step 305: Use the molten salt medium input from the hot salt tank to heat the water entering the steam generation module to generate steam.

[0092] In an embodiment of the present invention, a molten salt heat storage and release system can be set up. The molten salt heat storage and release system may include a fluidized bed reactor, an electric heating module partially placed in the fluidized bed reactor, and a heat extraction tube bundle placed in the fluidized bed reactor, a hot salt tank and a cold salt tank for storing molten salt medium, a circulation pipeline for transporting the molten salt medium, and a steam generating module connected between the hot salt tank and the cold salt tank. Heat storage and heat release are then achieved through the fluidized bed, the hot salt tank and the cold salt tank. The fluidized bed and the molten salt tank complement each other in heat storage; the small molten salt tank acts as a bridge to allow heat to be released in a stable and controllable manner.

[0093] 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.

[0094] 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, and when the computer program is executed by the processor, the above molten salt heat storage and release method is implemented.

[0095] 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 above molten salt heat storage and release method is implemented.

[0096] As for the method embodiment, since it is basically similar to the system embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] The above is a detailed introduction to a molten salt heat storage and release method and system. 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 molten salt heat storage and release system, characterized in that: The molten salt heat storage and release system includes a fluidized bed reactor, an electric heating module partially placed in the fluidized bed reactor, a heat extraction tube bundle placed in the fluidized bed reactor, a hot salt tank and a cold salt tank for storing molten salt medium, a circulation pipeline for transporting the molten salt medium, and a steam generation module connected between the hot salt tank and the cold salt tank; the fluidized bed reactor is filled with heat carrier particles for storing heat; the outlet of the cold salt tank is connected to the inlet of the heat extraction tube bundle through the circulation pipeline, and the inlet of the hot salt tank is connected to the outlet of the heat extraction tube bundle through the circulation pipeline; The electric heating module is used to heat the heat carrier particles when powered on; The cold salt tank is used to transport the molten salt medium to the heat extraction tube bundle through the circulation pipeline; The fluidized bed reactor is used to exchange heat between the heated heat carrier particles and the molten salt medium introduced into the inlet of the heat extraction tube bundle, and transport the heated molten salt medium to the hot salt tank through the outlet of the heat extraction tube bundle; The hot salt tank is used to transport the molten salt medium to the steam generation module through a circulation pipeline; The steam generation module is used to heat the water entering the steam generation module using the molten salt medium input from the hot salt tank to generate steam.

2. The system according to claim 1, characterized in that The molten salt heat storage and release system also includes an air supply module connected to the bottom of the fluidized bed reactor for supplying air to the fluidized bed reactor. The bottom of the fluidized bed reactor is provided with a high-temperature resistant air distribution plate or is piled with high-temperature resistant particles, which are used to evenly distribute the air entering the fluidized bed reactor; the top of the fluidized bed reactor is provided with an air supply outlet, and the air supply outlet is connected to the air supply module outside the fluidized bed reactor, and the air supply outlet is connected to a cyclone separator inside the fluidized bed reactor, and the cyclone separator is used to separate the heat carrier particles carried in the wind.

3. The system according to claim 2, characterized in that The steam generation module includes a water pipeline, water flows through the water pipeline, and the part of the water pipeline before the molten salt medium in the hot salt tank is heated is connected to the air supply outlet, so that the hot air in the fluidized bed reactor contacts the water pipeline through the air supply outlet to preheat the water in the output pipeline.

4. The system according to any one of claims 1 to 3, characterized in that A pump is arranged on the circulation pipeline between the cold salt tank and the fluidized bed reactor, and the pump is used to control the cold salt tank to transport the molten salt medium to the heat extraction tube bundle in the fluidized bed reactor through the circulation pipeline.

5. The system according to any one of claims 1 to 3, characterized in that The steam generation module is connected to the steam power generation module, and the steam power generation module is used to receive the steam generated by the steam generation module and use the steam to generate electrical energy.

6. The system according to any one of claims 1 to 3, characterized in that The melting point of the heat carrier particles is higher than 1500° C., and the particle size of the heat carrier particles ranges from 0 to 500 μm; the particle size of the high temperature resistant particles ranges from 1 mm to 30 mm.

7. The system according to any one of claims 1 to 3, characterized in that The heating method of the electric heating module includes any one of the following: Graphite electrode heating, silicon-molybdenum heating, infrared heating.

8. The system according to any one of claims 1 to 3, characterized in that The heat extraction tube bundle is a tube-in-tube or serpentine heat exchange tube.

9. The system according to any one of claims 1 to 3, characterized in that The molten salt heat storage and release system comprises a heat insulation layer arranged outside or inside the shell of the fluidized bed reactor, and the heat insulation layer is used to insulate and heat the fluidized bed reactor.

10. A molten salt heat storage and release method, characterized in that: Applied to the thermal energy storage system according to any one of claims 1 to 9, the method comprising: In a power-on state, the electric heating module is used to heat the heat carrier particles; Transporting the molten salt medium in the cold salt tank to the heat extraction tube bundle through the circulation pipeline; In the fluidized bed reactor, the heated heat carrier particles are heat exchanged with the molten salt medium introduced into the inlet of the heat extraction tube bundle, and the heated molten salt medium is transported to the hot salt tank through the outlet of the heat extraction tube bundle; transporting the molten salt medium stored in the hot salt tank to the steam generation module through a circulation pipeline; The molten salt medium input from the hot salt tank is used to heat the water entering the steam generation module to generate steam.

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