Fluidized bed energy storage system and heat storage and release method

Abstract

The embodiment of the invention provides a fluidized bed energy storage system and a heat storage and release method.The fluidized bed energy storage system comprises an energy supply unit, a fixed bed heat storage unit, a fluidized bed heat storage and release unit, a steam application unit and a circulating pipeline, and the energy supply unit, the fixed bed heat storage unit and the fluidized bed heat storage and release unit are sequentially and circularly connected through the circulating pipeline; a fluid working medium which flows circularly is introduced into the circulating pipeline, the fixed bed heat storage unit comprises a fixed bed and first particles which are filled in the fixed bed and exchange heat with the fluid working medium, and the fluidized bed heat storage and release unit comprises a fluidized bed, second particles which are filled in the fluidized bed and exchange heat with the fluid working medium, and a heat removal pipe embedded in the second particles; an inlet of the heat removal pipe is used for introducing water; the outlet of the heat removal pipe is connected with a steam application unit, so that the stability of the fluid working medium input by the fluidized bed can be ensured through the front fixed bed of the fluidized bed, and the stability of the steam application process is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage, and in particular to a fluidized bed energy storage system and a heat storage and release method. Background Art

[0002] At present, renewable energy has a wide range of applications, for example, steam generation, heating, hot water supply, etc. based on solar energy. However, a major disadvantage of renewable energy is intermittency and instability. For example, solar energy can only be collected during the day, and solar energy is unstable in different scenarios at different times of the day.

[0003] In order to realize the application of renewable energy, fluidized beds can be used for heat storage and release. However, due to the intermittent and unstable nature of renewable energy, the heat stored in the fluidized bed changes, which in turn leads to instability in heat release for power generation or other energy applications. Summary of the invention

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

[0005] A fluidized bed energy storage system, the fluidized bed energy storage system comprising an energy supply unit, a fixed bed heat storage unit, a fluidized bed heat storage and release unit, a steam application unit and a circulation pipeline, the circulation pipeline cyclically connects the energy supply unit, the fixed bed heat storage unit and the fluidized bed heat storage and release unit in sequence, a fluid medium circulates in the circulation pipeline, the fixed bed heat storage unit comprises a fixed bed and first particles filled in the fixed bed for heat exchange with the fluid medium, the fluidized bed heat storage and release unit comprises a fluidized bed, second particles filled in the fluidized bed for heat exchange with the fluid medium, and a heat extraction pipe buried in the second particles, the inlet of the heat extraction pipe is used for passing water; the outlet of the heat extraction pipe is connected to the steam application unit;

[0006] The energy supply unit is used to collect energy, and use the energy to heat the fluid working medium in the circulation pipeline, and transport the heated fluid working medium to the fixed bed heat storage unit through the circulation pipeline;

[0007] The fixed bed heat storage unit is used to perform heat exchange processing with the first particles and the fluid working medium in the fixed bed, and transport the fluid working medium to the fluidized bed heat storage unit through the circulation pipeline;

[0008] The fluidized bed heat storage and release unit is used to use the second particles to exchange heat with the fluid working medium in the fluidized bed during the heat storage stage, and output the fluid working medium after heat exchange to the energy supply unit through the circulation pipeline for heating; in the heat release stage, the second particles are used to store heat energy stored in the fluidized bed by heat exchange with the fluid working medium to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

[0009] Optionally, a circulation pump is provided on the circulation pipeline between the fluidized bed heat storage and release unit and the energy supply unit, and the circulation pump is used to control the fluid medium in the circulation pipeline to circulate along a preset circulation path when it is turned on.

[0010] Optionally, the first particles are encapsulated phase change material particles, the second particles are high temperature resistant solid particles, and the size of the first particles is greater than that of the second particles.

[0011] Optionally, the first particles are spherical particles with a particle size ranging from 10 mm to 50 mm, and the second particles are particles with a particle size ranging from 0 μm to 200 μm.

[0012] Optionally, the working range of the first particles is 200°C to 600°C.

[0013] Optionally, the fluidized bed heat storage and release unit also includes a gas inlet and a gas outlet. The fluidized bed heat storage and release unit is used to introduce gas into the fluidized bed from the gas inlet during the heat release stage, and the second particles are heated by the gas and the water in the heat absorption pipe to generate steam. During the heat storage stage, the gas supply to the fluidized bed is stopped.

[0014] Optionally, the gas velocity when passing gas through the fluidized bed is 2 to 10 times the minimum fluidization velocity of the second particles.

[0015] Optionally, the specific heat capacity of the fluid working medium is greater than 2000 kJ / (kg·°C).

[0016] Optionally, the fluidized bed is an adiabatic fluidized bed, and the shell of the fluidized bed is wrapped with a thermal insulation layer.

[0017] A heat storage and release method based on a fluidized bed heat storage system is applied to the fluidized bed energy storage system as described above, and the method comprises:

[0018] The energy supply unit is used to collect energy, and the energy is used to heat the fluid working medium in the circulation pipeline, and the heated fluid working medium is transported to the fixed bed of the fixed bed heat storage unit through the circulation pipeline;

[0019] After the first particles in the fixed bed are subjected to heat exchange treatment with the fluid working medium, the fluid working medium is transported to the fluidized bed of the fluidized bed heat storage and release unit through the circulation pipeline;

[0020] When the fluidized bed heat storage and release unit is in the heat storage stage, the fluid working medium is heat-exchanged with the second particles in the fluidized bed, and the fluid working medium after the heat exchange is transported to the energy supply unit for heating;

[0021] When the fluidized bed heat storage and release unit is in the heat release stage, the heat energy stored by the second particles in the fluidized bed through heat exchange with the fluid working medium is used to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

[0022] The embodiments of the present invention have the following advantages:

[0023] The embodiment of the present invention sets a fixed bed heat storage unit and a fluidized bed heat storage and release unit in the fluidized bed energy storage system, and can use the first particles of the fixed bed to perform preliminary heat exchange with the fluid working medium heated by the energy, and then transport the fluid working medium with surplus heat to the fluidized bed for heat exchange, and then after the fluidized bed releases heat, steam application is realized through the steam application unit. Therefore, in the embodiment of the present invention, the fixed bed in front of the fluidized bed can ensure the stability of the fluid working medium input into the fluidized bed, and even if the collected energy has problems such as intermittent and instability, the fluidized bed can achieve stable heat storage and heat release, thereby ensuring the stability of the steam application process. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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.

[0025] Figure 1a A fluidized bed energy storage system is provided in one embodiment of the present invention;

[0026] Figure 1b A fluidized bed energy storage system including a tower-type solar thermal unit is provided in one embodiment of the present invention;

[0027] Figure 1c A fluidized bed energy storage system including a trough-type solar thermal unit is provided in one embodiment of the present invention.

[0028] Figure 2 It is a flow chart of the steps of a heat storage and release method based on a fluidized bed heat storage system provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0029] 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.

[0030] Reference Figure 1a , showing a fluidized bed energy storage system provided by an embodiment of the present invention, the fluidized bed energy storage system 100 includes an energy supply unit 101, a fixed bed heat storage unit 102, a fluidized bed heat storage and release unit 103, a steam application unit 104 and a circulation pipeline 105, and the circulation pipeline circulates and connects the energy supply unit 101, the fixed bed heat storage unit 102 and the fluidized bed heat storage and release unit 103 in sequence.

[0031] The circulation connection of the circulation pipeline in the embodiment of the present invention can be specifically: the fluid working medium outlet end of the energy supply unit 101 is connected to the fluid working medium inlet end of the fixed bed heat storage unit 102 through the circulation pipeline 105, the fluid working medium outlet end of the fixed bed heat storage unit 102 is connected to the fluid working medium inlet end of the fluidized bed heat storage and release unit 103 through the circulation pipeline 105, and the fluid working medium outlet end of the fluidized bed heat storage and release unit 103 is connected to the fluid working medium inlet end of the energy supply unit 101 through the circulation pipeline. Thus, the circulation pipeline realizes the circulation connection between the energy supply unit 101, the fixed bed heat storage unit 102, and the fluidized bed heat storage and release unit 103.

[0032] The circulating pipe in the embodiment of the present invention is a circulating fluid medium. The fluid medium may be a fluid medium with high specific heat capacity. The fluid medium in the circulating pipe remains in a flowing liquid state, and based on its high specific heat capacity, it can achieve efficient heat exchange with the fixed bed heat storage unit and the fluidized bed heat storage and release unit. Specifically, the specific heat capacity of the fluid medium between the fixed bed heat storage unit and the energy supply unit is greater than 2000kJ / (kg·℃), and the fluid medium may include but is not limited to any one of binary molten salt and heat transfer oil.

[0033] The fixed bed heat storage unit in the embodiment of the present invention includes a fixed bed and first particles filled in the fixed bed to exchange heat with the fluid working medium. The first particles in the fixed bed can store heat by heat exchange with the fluid working medium. After the fluid working medium is introduced into the fixed bed, heat is exchanged and stored. The temperature in the fixed bed decreases from top to bottom, so that the temperature of the fluid working medium can be controlled within a certain range and a stable fluid working medium can be output.

[0034] In one example, the first particles can be packaged phase change material particles to fully contact with the fluid in the fixed bed to achieve heat exchange and improve heat exchange efficiency. The phase change material can be a molten salt phase change material, which has the advantages of small volume, high energy storage density and wide phase change temperature range; the packaging material of the phase change material can be set according to the selected phase change material characteristics and working scene, and there is no limitation on this in the embodiments of the present invention.

[0035] Phase change materials have problems such as corrosion of containers and high costs. By encapsulating phase change materials, problems such as phase segregation, liquid leakage, and corrosion of phase change materials can be significantly improved.

[0036] In one embodiment of the present invention, the first particles in the stationary phase are in direct contact with the fluid medium, and the first particles can be spherical particles with a particle size range of 10 mm to 50 mm, such as 10 mm, 20 mm, 40 mm, and 50 mm. The large-sized spherical setting can increase the contact area between the particles and the fluid medium, making it easy to achieve sufficient heat exchange.

[0037] In one embodiment of the present invention, the first particle may be a high temperature phase change material, and the working range of the high temperature phase change material is 200° C. to 600° C. For example, the working temperature may be 200° C., 200° C., 600° C.,

[0038] The fluidized bed heat storage and release unit in the embodiment of the present invention includes a fluidized bed, second particles filled in the fluidized bed for heat exchange with the fluid working medium, and a heat extraction pipe buried in the second particles, wherein the inlet of the heat extraction pipe is used for passing water; the outlet of the heat extraction pipe is connected to the steam application unit.

[0039] In one embodiment of the present invention, the second particles may be high temperature resistant solid particles, such as high temperature ceramic particles, quartz sand particles, etc. The size of the first particles is greater than the size of the second particles. Specifically, the second particles are particles with a particle size ranging from 0 μm to 200 μm, such as particles with a particle size of 50 μm, 100 μm, or 200 μm.

[0040] In the embodiment of the present invention, the functions of the various parts of the fluidized bed energy storage system are as follows:

[0041] The energy supply unit is used to collect energy, and use the energy to heat the fluid working medium in the circulation pipeline, and transport the heated fluid working medium to the fixed bed heat storage unit through the circulation pipeline. The energy is the energy to be collected, which can specifically include but is not limited to any one or more of solar energy, wind energy, valley electricity and other energy sources.

[0042] The fixed bed heat storage unit is used to perform heat exchange processing with the first particles and the fluid working medium in the fixed bed, and transport the fluid working medium to the fluidized bed heat storage and release unit through a circulation pipeline;

[0043] In practical applications, after the heated fluid enters the fixed bed of the fixed bed heat storage unit, it fully contacts and exchanges heat with the first particles, transferring part of the heat taken out from the energy source to the first particles in the fixed bed. After part of the heat is transferred, the temperature of the heated fluid is reduced to a certain range, and the fixed phase can be output, and the fluid carrying excess heat can be transported to the fluidized bed heat storage and release unit through a circulation pipeline.

[0044] The fluidized bed heat storage and release unit is used to use the second particles to exchange heat with the fluid working medium in the fluidized bed during the heat storage stage, and output the fluid working medium after heat exchange to the energy supply unit through a circulation pipeline for heating; in the heat release stage, the second particles and the fluid working medium in the fluidized bed are used to heat the heat energy stored in the heat exchange to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

[0045] In practical applications, there is a part of the circulating pipe inside the fluidized bed heat storage and release unit 103. Specifically, the part of the pipe can be set as a serpentine bend to achieve high-efficiency heat storage in the fluid bed. The fluidized bed is equivalent to a fixed bed in the heat storage stage, and realizes heat exchange and energy storage with the fluid working medium. In the heat release stage, the second particles are fluidized to release heat.

[0046] Specifically, in the heat storage stage, in the fluidized bed heat storage and release unit, the fluid working medium is input into the pipe inside the fluidized bed heat storage and release unit, and heat is exchanged with the second particles in a non-direct contact manner. The heat of the fluid working medium is transferred to the second particles in the fluidized bed to achieve heat storage. After the heat storage is completed, the fluid working medium is transported to the energy supply unit to achieve cyclic heat storage.

[0047] In the heat release stage, water flows through the inlet of the heat extraction pipe, and the second particles are fluidized to heat the water in the heat extraction pipe, thereby generating steam, which is then output from the outlet of the heat extraction pipe to the connected steam application unit, thereby realizing the application of steam in the steam application unit.

[0048] In the embodiment of the present invention, the steam application unit may be a steam power generation device, which generates electricity through steam to achieve electrical energy output. The steam application unit may also be a heating device, and the generated steam is transported to the heating pipe through an evaporator for heating. In addition, the water in the heat extraction pipe may be directly used to heat the generated hot water, and the hot water may be directly used.

[0049] In one embodiment of the present invention, a circulation pump is provided on the circulation pipeline between the fluidized bed heat storage and release unit and the energy supply unit. The circulation pump is used to control the fluid working medium in the circulation pipeline to circulate along a preset circulation path when it is turned on. By providing the circulation pump, the flow rate of the fluid working medium can be controlled and the heat exchange efficiency can be improved.

[0050] In one embodiment of the present invention, the fluidized bed heat storage and release unit further includes a gas inlet and a gas outlet. The fluidized bed heat storage and release unit is used to introduce gas from the gas inlet into the fluidized bed during the heat release phase, and the second particles are heated by the gas and the water in the heat absorption pipe to generate steam. During the heat storage phase, the supply of gas to the fluidized bed is stopped. By blowing gas into the fluidized bed during heat release, the output heat power can be increased.

[0051] The gas may be air or other thermally stable gas that does not chemically react with the second particles.

[0052] In one embodiment of the present invention, the gas velocity when passing gas through the fluidized bed is 2 to 10 times the minimum fluidization velocity of the second particles. By controlling the gas velocity, the heat release efficiency of the fluidized bed can be precisely controlled.

[0053] In one embodiment of the present invention, the fluidized bed is an adiabatic fluidized bed, and the shell of the fluidized bed is wrapped with an insulation layer. By providing an adiabatic fluidized bed and the insulation layer, heat exchange between the fluidized bed and the outside can be avoided, ensuring efficient heat storage and heat release efficiency of the fluidized bed.

[0054] Taking solar power generation as an example, the following describes how to implement solar power generation using the technical solution in the embodiment of the present invention:

[0055] As a renewable energy source, solar energy is used in many aspects of the country, such as steam power generation / heating, hot water supply, however, a major disadvantage of solar energy is its intermittency and instability. To solve this problem, most areas that use solar energy require energy storage systems. There are different types of energy storage solutions. One of the most important application areas of solar energy is power generation. Usually the most suitable energy storage system depends on the type of technology used for power generation. For solar power generation, there are two options: photovoltaic power generation and solar thermal power generation.

[0056] Compared with photovoltaic power generation, solar thermal power generation technology has the advantages of simple principle, large scale, easy energy storage, small fluctuation, long life, and less energy consumption and pollution in the manufacturing process.

[0057] The use of fluidized bed equipment in solar thermal power generation technology is conducive to improving the efficiency of heat absorption and heat release, but the heat storage method of particles in the fluidized bed is sensible heat storage, the power density is small, and the continuous temperature decay during the heat release process will lead to unstable heat output. On the other hand, in actual industrial applications, photovoltaic power generation is greatly affected by solar radiation resources, and the output power is volatile and intermittent.

[0058] In the embodiment of the present invention, solar power generation adopts photothermal power generation technology. The heat storage unit designed in the photothermal power generation technology is one of the effective methods to improve the stability of heat storage and release and ensure stable power generation. Specifically, the molten salt phase change material in the molten salt heat storage technology can be used to achieve heat storage. The molten salt phase change material has the advantages of small volume, high energy storage density and wide phase change temperature range.

[0059] In the fluidized bed heat storage system of solar thermal power generation, a fixed bed and a fluidized bed can be set up. The fixed bed performs preliminary heat storage, and the fluidized bed stores the excess heat of the fluid working medium. When power generation is needed, water is passed through to generate steam for steam power generation.

[0060] In solar thermal power generation technology, the energy supply unit may be a solar thermal unit, which may be a tower solar thermal unit or a trough solar thermal unit.

[0061] Among them, the tower-type solar thermal unit includes a collector (such as a heliostat), a heat absorber, and a thermal tower; the collector focuses sunlight and reflects it onto the heat absorber of the thermal tower to complete the conversion of light energy into thermal energy, heats the fluid flowing through the heat absorber, and the fluid carries the heat into the fixed bed storage unit.

[0062] The trough-type solar thermal unit includes a heat collecting trough and a heat absorbing pipeline; the heat collecting trough focuses sunlight and reflects it onto the heat absorbing pipeline arranged in the heat collecting trough, and the fluid flowing through the heat absorbing pipeline is heated and then flows into the fixed bed storage unit carrying heat.

[0063] like Figure 1b The figure shows a fluidized bed energy storage system including a tower solar thermal unit, and the fluid working medium can be a binary molten salt mixed with sodium nitrate and potassium nitrate. The collector focuses and reflects sunlight on the heat absorber of the solar thermal tower to complete the conversion of light energy to heat energy, and then the heat absorber heats the binary molten salt, and the binary molten salt carries heat into the fixed bed. The fixed bed is filled with spherical phase change material particles with a particle size range of 10 to 50 mm. The fluidized bed is filled with sand for storing and transferring heat, and the sand particle size range is 50-200μm. The heat extraction tube bundle in the fluidized bed is in the form of a serpentine tube, which transfers heat to the heat extraction tube bundle when the sand is fluidized, and then heats the water in the heat extraction tube bundle into steam, with a steam pressure of 4MPa and a temperature of 250℃. The steam is connected to the steam turbine generator set for steam power generation.

[0064] In the fluidized bed heat storage stage, the air inlet valve corresponding to the blower is closed, and the cold water inlet valve corresponding to the cold water pump is closed. In the fluidized bed heat release stage, the air inlet valve of the blower and the cold water inlet valve of the cold water pump are opened, and water and air are passed. The air fluidizes the sand, and then transfers the heat to the heat absorbing tube bundle, heating the cold water in the heat extracting tube bundle to generate steam.

[0065] like Figure 1c The figure shows a fluidized bed energy storage system including a trough-type solar thermal unit, and the fluid working medium can be thermal oil. The heat collecting trough focuses the sunlight and reflects it on the heat absorbing pipeline arranged in the heat collecting trough. After the hot fluid working medium in the heat absorbing pipeline is heated, it flows into the fixed bed with heat. The fixed bed is filled with spherical phase change material particles with a particle size range of 20 to 40 mm. The fluidized bed is filled with sand for storing and transferring heat, and the sand particle size range is 50-150μm. The heat extraction tube bundle in the fluidized bed is in the form of a serpentine tube. When the sand is fluidized, the heat is transferred to the heat extraction tube bundle, and then the water in the heat extraction tube bundle is heated into steam, and the steam is connected to the steam turbine generator set for steam power generation.

[0066] In an embodiment of the present invention, the fixed bed in front of the fluidized bed can ensure the stability of the fluid working medium input into the fluidized bed. Even if the collected energy has problems such as intermittent and instability, the fluidized bed can achieve stable heat storage and heat release, thereby ensuring the stability of the steam application process.

[0067] Reference Figure 2 , showing a flow chart of steps of a heat storage and release method based on a fluidized bed heat storage system provided by an embodiment of the present invention, wherein the fluidized bed energy storage system comprises an energy supply unit, a fixed bed heat storage unit, a fluidized bed heat storage and release unit, a steam application unit and a circulation pipeline, the circulation pipeline circulates and connects the energy supply unit, the fixed bed heat storage unit and the fluidized bed heat storage and release unit in sequence, a fluid working medium circulates in the circulation pipeline, the fixed bed heat storage unit comprises a fixed bed and first particles filled in the fixed bed for heat exchange with the fluid working medium, the fluidized bed heat storage and release unit comprises a fluidized bed, second particles filled in the fluidized bed for heat exchange with the fluid working medium, and a heat extraction pipe buried in the second particles, the inlet of the heat extraction pipe is used for passing water; the outlet of the heat extraction pipe is connected to the steam application unit;

[0068] The energy supply unit is used to collect energy and use the energy to heat the fluid working medium in the circulation pipeline, and transport the heated fluid working medium to the fixed bed heat storage unit through the circulation pipeline;

[0069] The fixed bed heat storage unit is used to perform heat exchange processing with the first particles and the fluid working medium in the fixed bed, and transport the fluid working medium to the fluidized bed heat storage and release unit through a circulation pipeline;

[0070] The fluidized bed heat storage and release unit is used to use the second particles to exchange heat with the fluid working medium in the fluidized bed during the heat storage stage, and output the fluid working medium after heat exchange to the energy supply unit through a circulation pipeline for heating; in the heat release stage, the second particles and the fluid working medium in the fluidized bed are used to heat the heat energy stored in the heat exchange to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

[0071] The fluidized bed energy storage system based on the above fluidized bed energy storage system may specifically include the following steps:

[0072] Step 201, using an energy supply unit to collect energy, and using the energy to heat the fluid working medium in the circulation pipeline, and transporting the heated fluid working medium to the fixed bed of the fixed bed heat storage unit through the circulation pipeline;

[0073] In practical applications, the energy supply unit can collect energy, and the collected energy can be any one or more of solar energy, wind energy, and valley electricity. The collected energy can be converted into heat energy to heat the fluid working medium flowing through the energy supply unit. The fluid working medium carries the heat energy through the circulation pipeline to the fixed bed of the fixed bed heat storage unit for preliminary energy storage.

[0074] Step 202, after the first particles in the fixed bed are subjected to heat exchange treatment with the fluid working medium, the fluid working medium is transported to the fluidized bed of the fluidized bed heat storage and release unit through a circulation pipeline;

[0075] The fixed bed can be filled with first particles. After the fluid medium flows into the fixed bed, it can directly contact with the first particles in the fixed bed to perform heat exchange treatment. Specifically, the fluid medium can flow in from the upper part of the fixed bed and flow out from the lower part, so as to achieve full contact with the first particles. During the heat exchange between the first particles and the fixed bed, the temperature in the fixed bed decreases from top to bottom. Therefore, after the fluid medium exchanges heat, the temperature can be stabilized within a certain range, that is, the fixed bed has a certain temperature control effect. The output fluid medium tends to be stable and controllable. The stable and controllable fluid medium is then transported to the fluidized bed of the fluidized bed heat storage and release unit.

[0076] Step 203, when the fluidized bed heat storage and release unit is in the heat storage stage, the fluid working medium is heat exchanged with the second particles in the fluidized bed, and the fluid working medium after the heat exchange is transported to the energy supply unit for heating;

[0077] The fluidized bed heat storage and release unit can realize both heat storage and heat release.

[0078] In the heat storage stage, part of the pipeline in the circulation pipeline is located in the fluidized bed, and the outside of this part of the pipeline is filled with second particles. When the fluid working medium carries excess heat into the pipeline in the fluidized bed, heat is exchanged with the second particles through the pipeline, and the heat is stored in the second particles, that is, the second particles in the fluidized bed and the fluid working medium perform non-contact heat exchange.

[0079] After the fluid medium has been heat exchanged in the fluidized bed, it can be transported to the energy supply unit through the circulation pipeline for a new round of heat storage. Thus, the entire system can achieve continuous heat storage and heat release.

[0080] Step 204, when the fluidized bed heat storage and release unit is in the heat release stage, the heat energy stored by the second particles and the fluid working medium in the fluidized bed is used to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

[0081] In the heat release stage, the heat stored in the second particles during the fluidization time heats the water introduced into the heat extraction pipe to generate steam, which is then transported to the steam application unit.

[0082] In an embodiment of the present invention, the fixed bed in front of the fluidized bed can ensure the stability of the fluid working medium input into the fluidized bed. Even if the collected energy has problems such as intermittent and instability, the fluidized bed can achieve stable heat storage and heat release, thereby ensuring the stability of the steam application process.

[0083] 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.

[0084] 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 fluidized bed energy storage method as described above is implemented.

[0085] 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 fluidized bed energy storage method as described above is implemented.

[0086] 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.

[0087] Those skilled in the art will appreciate that the embodiments of the present invention may be provided as systems, methods, or computer program products. Therefore, the embodiments of the present invention may take the form of complete hardware embodiments, complete software embodiments, or embodiments combining software and hardware. Moreover, the embodiments of the present invention may take the form of computer program products 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] The above is a detailed introduction to a fluidized bed energy storage system and a heat storage and release method. 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 fluidized bed energy storage system, characterized in that: The fluidized bed energy storage system includes an energy supply unit, a fixed bed heat storage unit, a fluidized bed heat storage and release unit, a steam application unit and a circulation pipeline. The circulation pipeline circulates and connects the energy supply unit, the fixed bed heat storage unit and the fluidized bed heat storage and release unit in sequence. A fluid medium circulates in the circulation pipeline. The fixed bed heat storage unit includes a fixed bed and first particles filled in the fixed bed for heat exchange with the fluid medium. The fluidized bed heat storage and release unit includes a fluidized bed, second particles filled in the fluidized bed for heat exchange with the fluid medium, and a heat extraction pipe buried in the second particles. The inlet of the heat extraction pipe is used for passing water. The outlet of the heat extraction pipe is connected to the steam application unit. The energy supply unit is used to collect energy, and use the energy to heat the fluid working medium in the circulation pipeline, and transport the heated fluid working medium to the fixed bed heat storage unit through the circulation pipeline; The fixed bed heat storage unit is used to perform heat exchange processing with the first particles and the fluid working medium in the fixed bed, and transport the fluid working medium to the fluidized bed heat storage unit through the circulation pipeline; The fluidized bed heat storage and release unit is used to use the second particles to exchange heat with the fluid working medium in the fluidized bed during the heat storage stage, and output the fluid working medium after heat exchange to the energy supply unit through the circulation pipeline for heating; in the heat release stage, the second particles are used to store heat energy stored in the fluidized bed by heat exchange with the fluid working medium to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

2. A fluidized bed energy storage system according to claim 1, characterized in that: A circulation pump is arranged on the circulation pipeline between the fluidized bed heat storage and release unit and the energy supply unit. The circulation pump is used to control the fluid working medium in the circulation pipeline to circulate along a preset circulation path when it is turned on.

3. A fluidized bed energy storage system according to claim 1, characterized in that: The first particles are encapsulated phase change material particles, the second particles are high temperature resistant solid particles, and the size of the first particles is greater than that of the second particles.

4. A fluidized bed energy storage system according to claim 3, characterized in that: The first particles are spherical particles with a particle size ranging from 10 mm to 50 mm, and the second particles are particles with a particle size ranging from 0 μm to 200 μm.

5. A fluidized bed energy storage system according to claim 3, characterized in that: The working range of the first particles is 200°C to 600°C.

6. The fluidized bed energy storage system according to any one of claims 1 to 6, characterized in that: The fluidized bed heat storage and release unit also includes a gas inlet and a gas outlet. The fluidized bed heat storage and release unit is used to introduce gas into the fluidized bed from the gas inlet during the heat release stage, and the second particles are heated by the gas and the water in the heat absorption pipe to generate steam. During the heat storage stage, the gas supply to the fluidized bed is stopped.

7. A fluidized bed energy storage system according to claim 6, characterized in that: The gas velocity when passing gas through the fluidized bed is 2 to 10 times the minimum fluidization velocity of the second particles.

8. A fluidized bed energy storage system according to any one of claims 1 to 7, characterized in that: The specific heat capacity of the fluid working medium is greater than 2000 kJ / (kg·°C).

9. A fluidized bed energy storage system according to any one of claims 1 to 7, characterized in that: The fluidized bed is an adiabatic fluidized bed, and a shell of the fluidized bed is wrapped with a heat-insulating layer.

10. A heat storage and release method based on a fluidized bed heat storage system, characterized in that: Applied to the fluidized bed energy storage system according to any one of claims 1 to 9, the method comprises: The energy supply unit is used to collect energy, and the energy is used to heat the fluid working medium in the circulation pipeline, and the heated fluid working medium is transported to the fixed bed of the fixed bed heat storage unit through the circulation pipeline; After the first particles in the fixed bed are subjected to heat exchange treatment with the fluid working medium, the fluid working medium is transported to the fluidized bed of the fluidized bed heat storage and release unit through the circulation pipeline; When the fluidized bed heat storage and release unit is in the heat storage stage, the fluid working medium is heat-exchanged with the second particles in the fluidized bed, and the fluid working medium after the heat exchange is transported to the energy supply unit for heating; When the fluidized bed heat storage and release unit is in the heat release stage, the heat energy stored by the second particles in the fluidized bed through heat exchange with the fluid working medium is used to heat the water entering the heat extraction pipeline to generate steam, and the steam is transported to the steam application unit.

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