Electromagnetic induction heating fluidized bed, heat and energy storage system and heat exchange method of fluidized bed

Abstract

The invention belongs to the technical field of energy storage devices, and particularly relates to an electromagnetic induction heating fluidized bed, a heat storage and energy storage system and a heat exchange method of the fluidized bed. The electromagnetic induction heating coil is arranged on the fluidized bed body and is used for heating a heat storage material in an inner cavity of the fluidized bed body; the cooling gas circuit passes through the electromagnetic induction heating coil, the cooling gas circuit is used for cooling the electromagnetic induction heating coil, and an outlet of the cooling gas circuit is communicated with an inner cavity of the fluidized bed body. Heat storage materials in the inner cavity of the fluidized bed body can be heated, Joule heat generated by the electromagnetic induction heating coil is fully utilized, natural heat which is absorbed by the electromagnetic induction heating coil and comes from the fluidized bed body is recycled, and the overall energy utilization efficiency of the heat storage system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage devices, and in particular to an electromagnetic induction heating fluidized bed, a heat storage energy storage system and a heat exchange method for a fluidized bed. Background Art

[0002] Thermal energy storage is a key technology that can achieve long-term and large-scale energy storage, and includes a variety of technical routes. One of the main energy storage media used in current thermal energy storage technology is molten salt. When molten salt is used as an energy storage medium, since the temperature resistance of conventional molten salt does not exceed 600°C, the molten salt will decompose after exceeding this temperature, resulting in the energy storage temperature of the thermal energy storage system using molten salt as the energy storage medium being difficult to continue to increase, affecting the total energy storage of the thermal energy storage system. In addition, molten salt is relatively expensive and has a high cost, resulting in a relatively high investment cost for the thermal energy storage system.

[0003] In addition to using molten salt heat storage for energy storage, some heat storage systems also use solid heat storage media for energy storage. Solid heat storage media are mainly magnesium oxide bricks, pebbles and other various high-temperature resistant powder materials. The temperature of solid heat storage media can reach above 750°C. At present, heat storage systems that use solid heat storage media for energy storage usually use resistance heating and electromagnetic induction heating coil heating. Since the power density and life of the resistance heating monomer are low, and high voltages above 10kV cannot be directly used, the resistance heating method has the problem of being difficult to apply on a large scale. When electromagnetic induction heating coils are used for heating, a cooling device is usually provided at the electromagnetic induction heating coil to cool the electromagnetic induction heating coil to avoid affecting the heating efficiency of the electromagnetic induction heating coil due to the excessive resistance of the electromagnetic induction heating coil. The current cooling device is usually liquid-cooled or air-cooled. The cooling efficiency of the air-cooled cooling device is low and it is difficult to meet the cooling requirements of the electromagnetic induction heating coil. The liquid-cooled cooling device has a good cooling effect, but it will absorb a lot of heat, and the liquid cooling device will also consume extra energy, resulting in a decrease in the overall energy utilization efficiency of the heat storage system. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide an electromagnetic induction heating fluidized bed, a heat storage and energy storage system and a heat exchange method of a fluidized bed, so as to solve the problem of low overall energy utilization efficiency of the heat storage and energy storage system in the prior art.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides an electromagnetic induction heated fluidized bed, comprising:

[0006] A fluidized bed body, wherein the fluidized bed body has an inner cavity for containing heat storage materials,

[0007] An electromagnetic induction heating coil, wherein the electromagnetic induction heating coil is disposed on the fluidized bed body and is used to heat the heat storage material in the inner cavity of the fluidized bed body;

[0008] A cooling gas path passes through the electromagnetic induction heating coil and is used to pass a gas medium to cool the electromagnetic induction heating coil. The outlet of the cooling gas path is connected to the gas inlet of the fluidized bed body to pass the heat-absorbed gas medium into the inner cavity of the fluidized bed body.

[0009] Optionally, the temperature range of the electromagnetic induction heating coil itself is 70°C to 400°C.

[0010] Optionally, in the cooling gas path, the temperature of the gas medium after cooling the electromagnetic induction heating coil is 150° C. to 240° C.

[0011] Optionally, the winding wire of the electromagnetic induction heating coil is in a hollow tubular shape, and the gas medium in the cooling gas path flows through the inner cavity of the winding wire.

[0012] Optionally, the cooling air circuit includes an air inlet pipeline and an air return pipeline, the air inlet end of the air inlet pipeline is used to receive the gas medium, and the air outlet end of the air inlet pipeline is connected to the head end of the winding wire.

[0013] The end of the winding wire is connected to the air inlet end of the return air pipeline, and the air outlet end of the return air pipeline is connected to the gas inlet of the fluidized bed body. The gas medium flowing through the winding wire is introduced into the fluidized bed body through the return air pipeline.

[0014] Optionally, the winding wire is coated with a heat-resistant and heat-insulating material, and the heat-resistant temperature of the heat-resistant and heat-insulating material is greater than 400°C.

[0015] Optionally, the electromagnetic induction heating fluidized bed further comprises a gas circulation pipeline, the two ends of which are respectively connected to the gas inlet of the fluidized bed body and the gas outlet of the fluidized bed body, and the gas in the gas circulation pipeline circulates to fluidize the heat storage material in the inner cavity of the fluidized bed body.

[0016] The present invention also provides a heat and energy storage system, comprising the electromagnetic induction heating fluidized bed as described above.

[0017] Optionally, the heat storage and energy storage system includes an energy accumulator, which is used to absorb thermal energy in the exhaust gas of the electromagnetic induction heating fluidized bed, the air inlet of the energy accumulator is connected to the gas outlet of the fluidized bed body, and the exhaust port of the energy accumulator is connected to the gas inlet of the fluidized bed body.

[0018] Optionally, the energy accumulator includes a plurality of energy storage units and bypass pipelines arranged in one-to-one correspondence with the energy storage units, the bypass pipelines are provided with on-off valves, the energy storage units are connected in series in sequence, and the bypass pipelines are connected in parallel with the corresponding energy storage units.

[0019] Optionally, the air inlet of each of the energy storage units is respectively connected to the gas outlet of the fluidized bed body, and the exhaust port of each of the energy storage units is respectively connected to the gas outlet of the fluidized bed body.

[0020] Optionally, a heat release pipeline is further included, and the heat release pipeline passes through the inner cavity of the energy storage device and / or the fluidized bed body.

[0021] Optionally, the heat storage and energy storage system also includes a heat release pipeline, on which a first heat exchanger is arranged, and a first heat exchange pipeline is connected between the air inlet of the energy accumulator and the exhaust port of the energy accumulator, and the first heat exchange pipeline passes through the first heat exchanger and exchanges heat with the heat release pipeline.

[0022] Optionally, the heat storage and energy storage system also includes a heat release pipeline, a second heat exchanger is arranged on the heat release pipeline, a second heat exchange pipeline is connected between the gas inlet of the fluidized bed body and the gas outlet of the fluidized bed body, and the second heat exchange pipeline passes through the second heat exchanger and exchanges heat with the heat release pipeline.

[0023] Optionally, the heat storage and energy storage system includes a hot storage tank, a heat radiator, a cold storage tank and a heat release pipeline, wherein the material outlet of the hot storage tank is connected to the material inlet of the heat radiator, and the material outlet of the heat radiator is connected to the material inlet of the cold storage tank.

[0024] The material inlet of the hot storage tank is communicated with the material outlet of the fluidized bed body, and the material outlet of the cold storage tank is communicated with the material inlet of the fluidized bed body.

[0025] A third heat exchange pipeline is connected between the gas inlet of the heat emitter and the gas outlet of the heat emitter. A third heat exchanger is arranged on the heat release pipeline. The third heat exchange pipeline passes through the third heat exchanger and exchanges heat with the heat release pipeline.

[0026] Optionally, the heat release pipeline passes through the heat release device and absorbs heat from the heat storage material in the heat release device. In the flow direction of the medium in the heat release pipeline, the heat release device is arranged after the third heat exchanger.

[0027] Optionally, the exothermic device is an exothermic fluidized bed.

[0028] Optionally, the exhaust port of the energy storage device is also connected to the inlet of the cooling air circuit.

[0029] Optionally, it comprises a hot storage tank, a heat release device, a cold storage tank and a heat release pipeline, the material outlet of the hot storage tank is communicated with the material inlet of the heat release device, the material outlet of the heat release device is communicated with the material inlet of the cold storage tank, the material inlet of the hot storage tank is communicated with the material outlet of the fluidized bed body, and the material outlet of the cold storage tank is communicated with the material inlet of the fluidized bed body.

[0030] The heat release pipeline passes through the heat release device and absorbs heat from the heat storage material in the heat release device.

[0031] The present invention also provides a heat exchange method for an electromagnetic induction heated fluidized bed, comprising the following steps:

[0032] The electromagnetic induction heating coil is used to heat the heat storage material in the fluidized bed cavity.

[0033] The electromagnetic induction heating coil is cooled by a gas medium,

[0034] The gas medium that absorbs heat at the electromagnetic induction heating coil is introduced into the inner cavity of the fluidized bed to heat and fluidize the heat storage material in the inner cavity of the fluidized bed.

[0035] As described above, the electromagnetic induction heating fluidized bed, the heat storage and energy storage system and the heat exchange method of the fluidized bed of the present invention have the following beneficial effects:

[0036] Since the outlet of the cooling gas path in the present invention is connected to the inner cavity of the fluidized bed body, the gas medium in the cooling gas path is introduced into the inner cavity of the fluidized bed body after absorbing the heat of the electromagnetic induction heating coil, and can heat the heat storage material in the inner cavity of the fluidized bed body, making full use of the Joule heat generated by the electromagnetic induction heating coil, and recovering the natural heat dissipation from the fluidized bed body absorbed by the electromagnetic induction heating coil, thereby improving the overall energy utilization efficiency of the heat storage system. At the same time, since the gas in the cooling gas path can recover the heat of the electromagnetic induction heating coil, the electromagnetic induction heating coil can work in a higher resistance state, which will not affect the overall heating effect of the fluidized bed body. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Shown is a schematic diagram of the structure of an electromagnetic induction heating fluidized bed in an embodiment of the present invention;

[0038] Figure 2 Shown is a first structural schematic diagram of a heat and energy storage system according to an embodiment of the present invention;

[0039] Figure 3 Shown is a second structural schematic diagram of a heat and energy storage system according to an embodiment of the present invention;

[0040] Figure 4 The third structural schematic diagram of the heat and energy storage system in the embodiment of the present invention is shown;

[0041] Figure 5 Shown is the fourth structural schematic diagram of the heat and energy storage system in an embodiment of the present invention.

[0042] Explanation of the reference numerals: inner cavity 1, electromagnetic induction heating coil 2, cooling gas path 3, gas-material separator 4, air distribution chamber 5, primary air distribution plate 6, secondary air distribution plate 7, thermal insulation layer 8, gas circulation pipeline 9, fluidized bed body 10, hot storage tank 11, heat release device 12, cold storage tank 13, first heat exchange pipeline 14, first heat exchanger 15, second heat exchange pipeline 16, second heat exchanger 17, third heat exchange pipeline 18, third heat exchanger 19, energy accumulator 20, energy storage unit 21, heat using device 30, heat release pipeline 31. DETAILED DESCRIPTION

[0043] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0044] It should be noted that the diagram provided in the present embodiment only illustrates the basic concept of the present invention in a schematic manner, so the diagram only shows the components related to the present invention rather than drawing according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be a random change, and the component layout type may also be more complicated. The structure, ratio, size, etc. illustrated in the drawings of the present specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that the present invention can implement, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effect that the present invention can produce and the purpose that can be achieved. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of narration, and are not used to limit the scope of the present invention. The change or adjustment of its relative relationship should also be regarded as the scope of the present invention without substantially changing the technical content.

[0045] See also Figure 1 to Figure 5 The present embodiment provides an electromagnetic induction heating fluidized bed, including a fluidized bed body 10, wherein the fluidized bed body 10 has an inner cavity 1 for containing heat storage materials. An electromagnetic induction heating coil 2 is disposed on the fluidized bed body 10, and the electromagnetic induction heating coil 2 is used to heat the heat storage materials in the inner cavity 1 of the fluidized bed body 10.

[0046] In actual situations, the electromagnetic induction heating coil 2 generates an alternating magnetic field, the inner wall of the inner cavity 1 of the fluidized bed body 10 is located in the magnetic field generated by the electromagnetic induction heating coil 2 and cuts the alternating magnetic lines of force, and an alternating current is generated in the inner wall of the inner cavity 1 of the fluidized bed body 10. The alternating current causes the inner wall of the inner cavity 1 of the fluidized bed body 10 to generate heat, and the heated inner wall transfers the heat to the heat storage material in the inner cavity 1, thereby heating the heat storage material.

[0047] At the same time, the gas medium is continuously introduced into the fluidized bed body 10. When the gas medium passes through the fluidized bed body 10, the granular heat storage material in the inner cavity 1 of the fluidized bed body 10 is in a suspended motion state, so that it can have good contact with the inner cavity 1 of the fluidized bed body 10, thereby improving the heat exchange efficiency between the inner cavity 1 of the fluidized bed body 10 and the heat storage material, and facilitating the electromagnetic induction heating coil 2 to heat the heat storage material.

[0048] In this embodiment, the fluidized bed body 10 also includes a cooling gas path 3 for cooling the electromagnetic induction heating coil 2. The cooling gas path 3 passes through the electromagnetic induction heating coil 2. The Joule heat generated by the electromagnetic induction heating coil 2 itself and the natural heat dissipated from the fluidized bed body 10 absorbed by the electromagnetic induction heating coil 2 can be carried away by the gas medium in the cooling gas path 3, thereby cooling the electromagnetic induction heating coil 2.

[0049] At the same time, in this embodiment, the outlet of the cooling gas path 3 is connected to the inner cavity 1 of the fluidized bed body 10. After absorbing the heat of the electromagnetic induction heating coil 2, the gas medium in the cooling gas path 3 can be passed into the inner cavity 1 of the fluidized bed body 10 to fluidize and heat the heat storage material in the inner cavity 1 of the fluidized bed body 10, so as to make full use of the resistance heat generated by the electromagnetic induction heating coil 2 and recover the natural heat dissipation from the fluidized bed body 10 absorbed by the electromagnetic induction heating coil 2, which is beneficial to improve the overall energy utilization efficiency of the heat storage system. Since the gas medium in the cooling gas path 3 recovers the heat of the electromagnetic induction heating coil 2, the electromagnetic induction heating coil 2 can work in a higher resistance state, and will not affect the overall heating effect of the electromagnetic induction heating coil 2 on the fluidized bed body 10.

[0050] Specifically, in this embodiment, the cooling gas circuit 3 includes an air inlet pipeline and an air return pipeline. The air inlet end of the air inlet pipeline is used to receive the gas medium, and the air outlet end of the air inlet pipeline is connected to the head end of the winding wire. The end of the winding wire is connected to the air inlet end of the air return pipeline, and the air outlet end of the air return pipeline is connected to the gas inlet of the fluidized bed body 10. The gas medium flowing through the winding wire is passed into the fluidized bed body 10 through the air return pipeline.

[0051] In this embodiment, the gas outlet of the fluidized bed body 10 is arranged at the top of the fluidized bed body 10, and the gas inlet of the fluidized bed body 10 is arranged at the bottom of the fluidized bed body 10. The inner wall of the fluidized bed body 10 is wrapped with an insulation layer 8 made of insulation material, and the electromagnetic induction heating coil 2 is wound around the insulation layer 8. The outer wall temperature of the insulation layer 8 should be lower than 100°C to reduce the heat loss of the fluidized bed as a whole.

[0052] In the inner cavity 1 of the fluidized bed body 10, a primary air distribution plate 6 and a secondary air distribution plate 7 are sequentially arranged from bottom to top. The primary air distribution plate 6 and the secondary air distribution plate 7 separate the inner cavity 1 of the fluidized bed body 10. There is an air distribution chamber 5 between the primary air distribution plate 6 and the secondary air distribution plate 7, and there is a fluidized bed layer above the secondary air distribution plate 7.

[0053] In this embodiment, the heat storage material in the fluidized bed body 10 can be selected from ceramic granular materials such as quartz sand and magnesium oxide, and the particle diameter thereof is between 10 μm and 3 mm. The air distribution chamber 5 is filled with coarse particles, and the fluidized bed layer is filled with fine particles. The filling height of the fine particles in the fluidized bed layer is about 3 times the diameter of the fluidized bed body 10.

[0054] Specifically, in this embodiment, a plurality of ribs are arranged on the inner wall of the fluidized bed, each of which extends along the axial direction of the fluidized bed body 10, and the position of the ribs in the height direction of the fluidized bed body 10 should be appropriate to correspond to the electromagnetic induction heating coil 2. The protruding height of the ribs is between 10 mm and 50 mm, and the spacing between adjacent ribs should be between 10 mm and 50 mm. The spacing between adjacent ribs can be shortened as much as possible, so as to arrange as many ribs as possible on the inner wall of the fluidized bed to increase the heat exchange area between the fluidized bed and the heat storage material.

[0055] In this embodiment, the electromagnetic induction heating coil 2 adopts an adjustable voltage of 0 to 10 kV, and its power density is 0 to 60 kW / m 2 Adjustable to suit heating power requirements.

[0056] In this embodiment, a gas-material separator 4 is provided between the fluidized bed layer and the gas outlet of the fluidized bed body 10 to separate the heat storage material in the exhaust gas of the fluidized bed body 10 and reduce the amount of heat storage material carried out in the exhaust gas of the fluidized bed body 10. In this embodiment, the gas-material separator 4 is a cyclone separator. The cyclone separator relies on the tangential introduction of the airflow to cause the airflow to rotate. During the rotation of the airflow, solid particles with large inertia are thrown to the outer wall and separated from the gas. The cyclone separator has the advantages of simple structure, high separation efficiency, easy maintenance and low price. The cyclone separator can be set to two or more stages to ensure the separation effect of the heat storage material. The separated heat storage material is returned to the fluidized bed layer to maintain the high stability of the heat storage material in the fluidized bed layer.

[0057] In actual situations, the height of the electromagnetic induction heating coil 2 should be arranged appropriately, and the lower edge of the electromagnetic induction heating coil 2 should be sufficiently higher than the secondary air distribution plate 7, so as to prevent abnormal heating of the components at the bottom of the fluidized bed body 10. Specifically, the heat release distance of the lower edge of the electromagnetic induction heating coil 2 above the secondary air distribution plate 7 should reach 1 / 5 of the inner diameter of the electromagnetic induction heating coil 2.

[0058] At the same time, the upper edge of the electromagnetic induction heating coil 2 should be consistent with the height of the heat storage material in the inner cavity 1 of the fluidized bed body 10 to maximize the heating area of ​​the electromagnetic induction heating coil 2 and avoid overheating caused by insufficient heat exchange of the electromagnetic induction heating coil 2.

[0059] In this embodiment, the inner wall of the inner cavity 1 of the fluidized bed body 10 can be made of conductive, wear-resistant and chemically stable materials with a temperature resistance of more than 1100°C, such as high-temperature alloys, high-temperature resistant austenitic stainless steel, etc. The inner wall of the inner cavity 1 of the fluidized bed body 10 can also be made of conductive, wear-resistant and chemically stable materials with a temperature resistance of more than 1600°C, such as SiC, graphite, etc. When the inner wall of the inner cavity 1 of the fluidized bed body 10 is made of easily oxidized materials such as SiC and graphite, atmosphere protection should be used.

[0060] In this embodiment, the temperature range of the electromagnetic induction heating coil 2 itself is 70° C. to 400° C. In this embodiment, after heat exchange with the electromagnetic induction heating coil 2 , the temperature of the gas medium in the cooling gas path 3 is 150° C. to 240° C.

[0061] The temperature of the conventional electromagnetic induction heating coil 2 cannot exceed 70°C to maintain a low resistance. When cooling, cooling water is used, and the water temperature does not exceed 60°C. The electromagnetic induction heating coil 2 in this embodiment uses gas cooling instead, and the heat carried by the gas medium can be utilized. The temperature of the electromagnetic induction heating coil 2 itself can be controlled within 400°C, and the temperature of the gas medium can be increased to 240°C. The increase in the temperature of the gas medium is conducive to the outward heat dissipation of the gas medium, which is convenient for recycling the heat carried by the gas medium.

[0062] In some embodiments, a shell is disposed outside the electromagnetic induction heating coil 2, the electromagnetic induction heating coil 2 is disposed in the shell, and a cooling gap is left between the electromagnetic induction heating coil 2 and the shell. The gas medium can flow in the cooling gap to contact and exchange heat with the electromagnetic induction heating coil 2, thereby cooling the electromagnetic induction heating coil 2.

[0063] In this embodiment, the winding wire of the electromagnetic induction heating coil 2 is tubular, and the gas medium in the cooling gas path 3 flows through the cavity inside the winding wire, that is, the electromagnetic induction heating coil 2 is wound with a hollow tubular conductive material, and the interior thereof is ventilated. The gas medium in the cooling gas path 3 passes through the cavity inside the winding wire to cool the winding wire, which has the advantages of short cooling distance and good cooling effect. In this embodiment, the winding wire is a copper tube, which has excellent electrical and thermal conductivity and is suitable for use as the winding wire of the electromagnetic induction heating coil 2.

[0064] In this embodiment, the electromagnetic induction heating coil 2 should be well insulated to ensure that the withstand voltage of the electromagnetic induction heating coil 2 is above 25 kV. The insulating material of the electromagnetic induction heating coil 2 can be polyimide, ceramic fiber tape or knotted material.

[0065] In this embodiment, the winding wire of the electromagnetic induction heating coil 2 is also coated with a heat-resistant insulation material, and the heat-resistant insulation material has a heat-resistant temperature greater than 400° C. Specifically, the heat-resistant insulation material can be selected from inorganic materials such as polyimide, ceramic materials, etc. with a temperature resistance exceeding 400° C.

[0066] like Figure 1 As shown, in this embodiment, the electromagnetic induction heating fluidized bed also includes a gas circulation pipeline 9, the two ends of the gas circulation pipeline 9 are respectively connected to the gas inlet of the fluidized bed body 10 and the gas outlet of the fluidized bed body 10, and the gas in the gas circulation pipeline 9 circulates to fluidize the heat storage material in the inner cavity 1 of the fluidized bed body 10.

[0067] A circulation fan is provided on the gas circulation pipeline 9, which drives the gas in the gas circulation pipeline 9 to flow, enter the fluidized bed body 10 through the gas inlet of the fluidized bed body 10, and then return to the gas circulation pipeline 9 from the gas outlet of the fluidized bed body 10 to complete the cycle.

[0068] In this embodiment, the gas outlet end of the gas circulation pipeline 9 is connected to the gas inlet of the fluidized bed body 10. In the cooling gas circuit 3, the gas inlet end of the gas inlet pipeline and the gas outlet end of the gas return pipeline are both connected to the gas outlet end of the gas circulation pipeline 9. In the flow direction of the gas medium in the gas circulation pipeline 9, the connection position between the gas inlet end of the gas inlet pipeline and the gas circulation pipeline 9 is located upstream of the connection position between the gas outlet end of the gas return pipeline and the gas circulation pipeline 9. At the same time, structures such as one-way valves can also be respectively provided on the gas inlet pipeline and the gas return pipeline to prevent the gas medium in the cooling gas circuit 3 from backflowing.

[0069] In this embodiment, the insulating pipe at the connection between the winding conductor and the gas circulation pipeline 9 should be made of a material with a temperature resistance exceeding 250° C., such as polytetrafluoroethylene, fluororubber, silicone rubber, polyether polyketone, polyphenylene sulfide and various ceramic materials.

[0070] like Figure 2 to Figure 5 As shown, this embodiment also provides a heat storage and energy storage system, including the electromagnetic induction heating fluidized bed as above.

[0071] In this embodiment, the heat storage energy storage system includes an energy accumulator 20, which is used to absorb the heat energy in the exhaust gas of the electromagnetic induction heating fluidized bed. The air inlet of the energy accumulator 20 is connected to the gas outlet of the fluidized bed body 10, and the exhaust port of the energy accumulator 20 is connected to the gas inlet of the fluidized bed body 10.

[0072] Specifically, in this embodiment, the energy storage device 20 includes a plurality of energy storage units 21 and bypass pipelines arranged in one-to-one correspondence with the energy storage units 21, each energy storage unit 21 is connected in series in sequence, and each bypass pipeline is connected in parallel with the corresponding energy storage unit 21. In this embodiment, a stop valve is arranged on the bypass pipeline, and the flow path of the gas medium in the energy storage device 20 can be adjusted by opening or closing the stop valve on the bypass pipeline.

[0073] The air inlet of each energy storage unit 21 is respectively connected to the gas outlet of the fluidized bed body 10, and the exhaust port of each energy storage unit 21 is respectively connected to the gas inlet of the fluidized bed body 10. Each bypass pipeline is provided with a valve to control the connection between each energy storage unit 21 and the gas outlet of the fluidized bed body 10.

[0074] In this embodiment, the energy storage unit 21 is a fixed bed, and the heat storage material in the fixed bed is consistent with the heat storage material in the fluidized bed body 10. The fixed bed can adopt a box-type structure, including an air inlet and an exhaust port. After the high-temperature air discharged from the fluidized bed body 10 passes through the fixed bed, the temperature is reduced, and the energy is transferred to the heat storage material in the high-temperature state in the fixed bed. In this embodiment, the fixed bed is configured in steps to fully absorb the heat of the high-temperature air discharged from the fluidized bed body 10, so that the temperature of the high-temperature air discharged from the fluidized bed body 10 after passing through the energy storage device 20 is lower than 150°C.

[0075] In some embodiments, the heat storage system further includes a heat release pipeline 31, which passes through the inner cavity 1 of the energy storage device 20 and / or the fluidized bed body 10. A heat-using device 30 such as a steam turbine can be arranged on the heat release pipeline 31 to convert thermal energy into other forms of energy such as mechanical energy for utilization. Figure 2 As shown, the heat release pipeline 31 can pass through the energy accumulator 20 and the inner cavity 1 of the fluidized bed body 10 at the same time, and absorb heat from the energy accumulator 20 and the fluidized bed body 10 respectively. It has a simple structure and high heat absorption efficiency.

[0076] In existing thermal energy storage systems using fluidized beds, the high-temperature gas discharged from the fluidized bed is usually recovered using a heat exchanger, and the use of a heat exchanger is equivalent to a heat release process, that is, the heat storage process and the heat release process in the existing thermal energy storage system are coupled. When the heat storage process and the heat release process of the thermal energy storage system need to be separated, the existing thermal energy storage system cannot implement this process.

[0077] In this embodiment, the heat storage energy storage system includes an energy storage device 20. The energy storage device 20 can independently store heat without recovering energy in a heat release manner, thereby achieving decoupling of heat storage and heat release.

[0078] like Figure 3 As shown, in some embodiments, the heat storage and energy storage system also includes a heat release pipeline 31, on which a first heat exchanger 15 is provided, and a first heat exchange pipeline 14 is connected between the air inlet of the energy accumulator 20 and the exhaust port of the energy accumulator 20, and the first heat exchange pipeline 14 passes through the first heat exchanger 15 and exchanges heat with the heat release pipeline 31. The high-temperature gas discharged from the energy accumulator 20 is transferred to the heat release pipeline 31 through the first heat exchange pipeline 14, thereby supplying energy to the outside. In this embodiment, a first heat release fan is provided on the first heat exchange pipeline 14 to drive the gas in the first heat exchange pipeline 14 to circulate in the first heat exchange pipeline 14 and the energy accumulator 20.

[0079] Specifically, one end of the first heat exchange pipeline 14 is connected to the exhaust port of each energy storage unit 21, and the other end of the first heat exchange pipeline 14 is connected to the air inlet of each energy storage unit 21. The high-temperature gas discharged from each energy storage unit 21 can flow through the first heat exchange pipeline 14 independently, thereby realizing independent heat release of each energy storage unit 21.

[0080] like Figure 3 As shown, a second heat exchanger 17 may also be provided on the heat release pipeline 31, and a second heat exchange pipeline 16 is connected between the gas inlet of the fluidized bed body 10 and the gas outlet of the fluidized bed body 10, and the second heat exchange pipeline 16 passes through the second heat exchanger 17 and exchanges heat with the heat release pipeline 31. The second heat exchanger 17 allows the gas discharged from the fluidized bed body 10 to directly exchange heat with the medium in the heat release pipeline 31, shortening the heat exchange path, which is beneficial to improving the overall efficiency of the heat storage system in supplying energy to the outside.

[0081] like Figure 4As shown, in some embodiments, the heat storage energy storage system includes a hot storage tank 11, a heat emitter 12, a cold storage tank 13, and also includes a heat release pipeline 31. The material inlet of the hot storage tank 11 is connected to the material outlet of the fluidized bed body 10, and the material outlet of the hot storage tank 11 is connected to the material inlet of the heat emitter 12. The heat storage material heated by the fluidized bed body 10 can enter the hot storage tank 11 for storage. The heat storage tank 11 is provided with an insulation layer 8 outside to reduce the heat loss of the heat storage material in the hot storage tank 11. When the heat storage material in the heat emitter 12 is insufficient, the heat storage material in the hot storage tank 11 can enter the heat emitter 12 for heat release.

[0082] The material outlet of the heat radiator 12 is connected with the material inlet of the cold storage tank 13, and the heat storage material after heat release and cooling in the heat radiator 12 can enter the cold storage tank 13 for storage. The material outlet of the cold storage tank 13 is connected with the material inlet of the fluidized bed body 10. When the heat storage material in the fluidized bed body 10 enters the heat storage tank for storage, or when the height of the heat storage material in the fluidized bed body 10 decreases due to excessive heat storage material brought out by the airflow, the heat storage material in the cold storage tank 13 can be supplemented to the fluidized bed body 10 to keep the height of the heat storage material in the fluidized bed body 10 stable.

[0083] In this embodiment, the material inlet of the fluidized bed body 10 is arranged at the upper part of the fluidized bed body 10 , and the material outlet of the fluidized bed body 10 is arranged at the lower part of the fluidized bed body 10 , which is conducive to heat exchange of stored materials in the fluidized bed body 10 .

[0084] The third heat exchange pipeline 18 is connected between the gas inlet of the radiator 12 and the gas outlet of the radiator 12, and the third heat exchanger 19 is arranged on the heat release pipeline 31. The third heat exchange pipeline 18 passes through the third heat exchanger 19 and exchanges heat with the heat release pipeline 31. The gas circulates in the third heat exchange pipeline 18 and the radiator 12, and the gas releases heat to the medium in the heat release pipeline 31 through the third heat exchanger 19, thereby realizing energy release.

[0085] like Figure 5 As shown, in some embodiments, the heat release pipeline 31 also passes through the heat release device 12 and absorbs heat from the heat storage material in the heat release device 12. In the flow direction of the medium in the heat release pipeline 31, the heat release device 12 is arranged after the third heat exchanger 19. The heat release device 12 can directly heat the medium in the heat release pipeline 31 to improve the heating efficiency. The first heat exchanger 15 and the third heat exchanger 19 can preheat the medium in the heat release pipeline 31, increase the final temperature of the medium flowing out of the heat release pipeline 31, and facilitate the utilization of the heat in the heat release pipeline 31.

[0086] Specifically, in this embodiment, the heat release device 12 is a heat release fluidized bed. The fluidized bed has the advantages of high heat exchange efficiency, easy maintenance of uniform temperature in the bed, and convenient transportation of heat storage materials.

[0087] In this embodiment, the exhaust port of the energy accumulator 20 is also connected to the inlet of the cooling gas path 3 , and the gas exhausted from the energy accumulator 20 can enter the cooling gas path 3 to cool the electromagnetic induction heating coil 2 .

[0088] In this embodiment, a heat exchange fluid flows in the heat release pipeline 31, and a heat exchange fluid pump is provided on the heat release pipeline 31 to drive the heat exchange fluid to flow in the heat release pipeline 31. In this embodiment, water is used as the heat exchange fluid in the heat release pipeline 31. Water has the advantages of high specific heat capacity, wide source, low cost, etc. Figure 4 As shown, in some embodiments, a circulating fan may be separately provided on the first heat exchange pipeline 14. Figure 5 As shown, in this embodiment, the first heat exchange pipeline 14 and the gas circulation pipeline 9 share the same circulation fan to simplify the structure of the heat storage and energy storage system and save costs.

[0089] exist Figure 1 to Figure 5 In the figure, the cooling gas circuit 3 is represented by a thin dotted line, the first heat exchange pipeline 14, the second heat exchange pipeline 16, the third heat exchange pipeline 18 and the gas circulation pipeline 9 are represented by a thin solid line, the heat release pipeline 31 is represented by a thick solid line, and the circulation pipeline of the heat storage material is represented by a thick dotted line.

[0090] This embodiment also provides a heat exchange method for an electromagnetic induction heated fluidized bed, comprising the following steps:

[0091] The electromagnetic induction heating coil 2 is used to heat the heat storage material in the inner cavity 1 of the fluidized bed body 10.

[0092] The electromagnetic induction heating coil 2 is cooled by the gas medium.

[0093] The gas medium that absorbs heat at the electromagnetic induction heating coil 2 is introduced into the inner cavity 1 of the fluidized bed body 10 , and is used for heating and fluidizing the heat storage material in the inner cavity 1 of the fluidized bed body 10 .

[0094] Specifically, Figure 5For example, in actual situations, during the energy storage stage, the circulating fan drives the gas medium in the gas circulation pipeline 9 to flow into the fluidized bed body 10, and part of the gas medium enters the fluidized bed body 10 to directly fluidize the heat storage material in the fluidized bed body 10. The rest of the gas medium enters the cooling gas path 3 and flows through the winding wire of the electromagnetic induction heating coil 2 to absorb heat and cool the electromagnetic induction heating coil 2. The gas after the electromagnetic induction heating coil 2 absorbs heat enters the fluidized bed body 10. The gas medium that directly enters the fluidized bed body 10 in the gas circulation pipeline 9 and the gas medium that absorbs the heat of the electromagnetic induction heating coil 2 in the cooling gas path 3 together keep the heat storage material in the fluidized bed body 10 in a fluidized state, so as to enhance the heat transfer effect between the heat storage material and the wall surface of the inner cavity 1 of the fluidized bed body 10, and make the temperature of each part of the heat storage material uniform.

[0095] During the energy storage stage, the valves on the first heat exchange pipeline 14 and the third heat exchange pipeline 18 need to be closed to prevent the high-temperature gas from flowing through the first heat exchanger 15 and the third heat exchanger 19 .

[0096] At the same time, in the energy storage device 20, by controlling the valve on the bypass line, the energy storage units 21 are connected in series in sequence, and the high-temperature gas discharged from the gas outlet of the fluidized bed body 10 can flow through each fixed bed in sequence. After the high-temperature gas flows through each fixed bed, it is cooled to below 150°C. As the energy storage time increases, when the temperature of the fixed bed closest to the gas outlet of the fluidized bed body 10 reaches the upper limit, the valve on the corresponding bypass line of the fixed bed closest to the gas outlet of the fluidized bed body 10 is opened to open the bypass line, and the high-temperature air discharged from the gas outlet of the fluidized bed body 10 is directly introduced into the next fixed bed through the bypass line. By performing the same operation, the remaining fixed beds can gradually exit the energy storage process and the temperature will no longer rise. Gas temperature stability and system stability are achieved by configuring fixed beds in a step-by-step manner and switching related valves.

[0097] After the heat storage material is heated to a preset temperature in the fluidized bed body 10, it can enter the hot storage tank 11 through the discharge port at the bottom of the fluidized bed body 10, that is, the material outlet. In the heat release stage, the hot storage tank 11 can gradually discharge the high-temperature heat storage material to the heat release fluidized bed, and the high-temperature heat storage material can enter the cold storage tank 13 after gradually cooling down in the heat release fluidized bed. After the heated heat storage material enters the hot storage tank 11 from the induction heating fluidized bed, the corresponding cold heat storage material should be supplemented from the cold storage tank 13 to enter the fluidized bed body 10 to ensure the high stability of the heat storage material in the fluidized bed body 10.

[0098] In the heat release stage, firstly, all the high-temperature heat storage materials in the fluidized bed body 10 are placed into the heat storage tank 11 through the discharge port at the bottom of the fluidized bed body 10, waiting to enter the heat release fluidized bed for heat release. Close the valve on the gas circulation pipeline 9, so that the fluidized bed body 10 enters the furnace insulation state, waiting to be loaded with cold heat storage materials before energy storage begins. Open the valve on the first heat exchange pipeline 14, and under the drive of the circulation fan, the low-temperature gas enters the energy storage device 20 and is heated, taking away the heat.

[0099] The heated gas enters the first heat exchanger 15. In the first heat exchanger 15, the low-temperature fluid in the heat release pipeline 31 is in the tube side, and the heated gas is in the shell side. After the gas releases heat and cools down, it returns to the circulation fan again, and enters the energy storage device 20 again under the action of the circulation fan to continue to take away the heat stored in the fixed bed.

[0100] The low-temperature heat exchange fluid in the heat release pipeline 31 is preheated in the first heat exchanger 15 under the drive of the heat exchange fluid pump, and then enters the second heat exchanger 17 to heat exchange and heat up with the high-temperature gas discharged from the fluidized bed body 10, and then enters the coil heat exchanger in the fluidized bed body 10, and further increases the temperature under the dual effects of radiation and convection to obtain a high-temperature heat exchange fluid. The high-temperature heat exchange fluid finally enters a heat-using device 30 such as a steam generation and superheating system, a heat user heat transfer fluid system, etc., to heat steam or other heat transfer fluids. The cooled heat exchange fluid returns to the heat exchange fluid pump and enters the next cycle under the drive of the heat exchange fluid pump.

[0101] In summary, the electromagnetic induction heating fluidized bed, heat storage and energy storage system and heat exchange method of the fluidized bed provided in this embodiment, since the outlet of the cooling gas path 3 is connected to the inner cavity 1 of the fluidized bed body 10, the gas in the cooling gas path 3 can be introduced into the inner cavity 1 of the fluidized bed body 10 after absorbing the heat of the electromagnetic induction heating coil 2, thereby heating the heat storage material in the inner cavity 1 of the fluidized bed body 10, so as to make full use of the Joule heat generated by the electromagnetic induction heating coil 2, and recover the natural heat dissipation from the fluidized bed body 10 absorbed by the electromagnetic induction heating coil 2, thereby improving the overall energy utilization efficiency of the heat storage system. At the same time, since the gas in the cooling gas path 3 can recover the heat of the electromagnetic induction heating coil 2, the electromagnetic induction heating coil 2 can work in a higher resistance state, and will not affect the overall heating effect of the fluidized bed body 10.

[0102] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An electromagnetic induction heated fluidized bed, characterized in that: include: A fluidized bed body, wherein the fluidized bed body has an inner cavity for containing heat storage materials, An electromagnetic induction heating coil, wherein the electromagnetic induction heating coil is disposed on the fluidized bed body and is used to heat the heat storage material in the inner cavity of the fluidized bed body; A cooling gas path passes through the electromagnetic induction heating coil and is used to pass a gas medium to cool the electromagnetic induction heating coil. The outlet of the cooling gas path is connected to the gas inlet of the fluidized bed body to pass the heat-absorbed gas medium into the inner cavity of the fluidized bed body.

2. The electromagnetic induction heating fluidized bed according to claim 1, characterized in that: The temperature range of the electromagnetic induction heating coil itself is 70°C to 400°C.

3. The electromagnetic induction heating fluidized bed according to claim 2, characterized in that: In the cooling gas path, the temperature of the gas medium after cooling the electromagnetic induction heating coil is 150°C to 240°C.

4. The electromagnetic induction heating fluidized bed according to claim 1, characterized in that: The winding wire of the electromagnetic induction heating coil is in a hollow tubular shape, and the gas medium in the cooling gas path flows through the hollow inner cavity of the winding wire.

5. The electromagnetic induction heating fluidized bed according to claim 4, characterized in that: The cooling air circuit includes an air inlet pipeline and an air return pipeline. The air inlet end of the air inlet pipeline is used to receive the gas medium, and the air outlet end of the air inlet pipeline is connected to the head end of the winding wire. The air inlet end of the air return pipeline is connected to the end of the winding wire, and the air outlet end of the air return pipeline is connected to the gas inlet of the fluidized bed body. The gas medium flowing through the winding wire is introduced into the fluidized bed body through the air return pipeline.

6. The electromagnetic induction heating fluidized bed according to claim 2, characterized in that: The electromagnetic induction heating coil is coated with a heat-resistant heat-insulating material, and the heat-resistant temperature of the heat-resistant heat-insulating material is greater than 400°C.

7. The electromagnetic induction heating fluidized bed according to claim 1, characterized in that: The electromagnetic induction heating fluidized bed also includes a gas circulation pipeline, the two ends of which are respectively connected to the gas inlet of the fluidized bed body and the gas outlet of the fluidized bed body. The gas in the gas circulation pipeline circulates to fluidize the heat storage material in the inner cavity of the fluidized bed body.

8. A heat and energy storage system, characterized in that: It comprises the electromagnetic induction heating fluidized bed as described in any one of claims 1 to 7.

9. The heat and energy storage system according to claim 8, characterized in that: The heat storage and energy storage system also includes an energy accumulator, which is used to absorb thermal energy in the exhaust gas of the electromagnetic induction heating fluidized bed. The air inlet of the energy accumulator is connected to the gas outlet of the fluidized bed body, and the exhaust port of the energy accumulator is connected to the gas inlet of the fluidized bed body.

10. The heat and energy storage system according to claim 9, characterized in that: The energy accumulator includes a plurality of energy storage units and bypass pipelines arranged one by one corresponding to the energy storage units, the bypass pipelines are provided with on-off valves, the energy storage units are connected in series in sequence, and the bypass pipelines are connected in parallel with the corresponding energy storage units.

11. The heat and energy storage system according to claim 9, characterized in that: The heat and energy storage system further comprises a heat release pipeline, and the heat release pipeline passes through the inner cavity of the energy storage device and / or the fluidized bed body.

12. The heat and energy storage system according to claim 9, characterized in that: It also includes a heat release pipeline, on which a first heat exchanger is arranged, and a first heat exchange pipeline is connected between an air inlet of the energy accumulator and an exhaust port of the energy accumulator, and the first heat exchange pipeline passes through the first heat exchanger and exchanges heat with the heat release pipeline.

13. The heat and energy storage system according to claim 9, characterized in that: It also includes a heat release pipeline, on which a second heat exchanger is arranged, a second heat exchange pipeline is connected between the gas inlet of the fluidized bed body and the gas outlet of the fluidized bed body, and the second heat exchange pipeline passes through the second heat exchanger and exchanges heat with the heat release pipeline.

14. The thermal energy storage system according to any one of claims 9 to 13, characterized in that: The exhaust port of the energy storage device is also communicated with the inlet of the cooling air path.

15. The thermal energy storage system according to any one of claims 8 to 10, characterized in that: It comprises a hot storage tank, a heat release device, a cold storage tank and a heat release pipeline, wherein the material outlet of the hot storage tank is communicated with the material inlet of the heat release device, the material outlet of the heat release device is communicated with the material inlet of the cold storage tank, the material inlet of the hot storage tank is communicated with the material outlet of the fluidized bed body, and the material outlet of the cold storage tank is communicated with the material inlet of the fluidized bed body. The heat release pipeline passes through the heat release device and absorbs heat from the heat storage material in the heat release device.

16. A heat exchange method for electromagnetic induction heating fluidized bed, characterized in that: The electromagnetic induction heating coil is used to heat the heat storage material in the fluidized bed cavity. The electromagnetic induction heating coil is cooled by a gas medium, The gas medium that absorbs heat at the electromagnetic induction heating coil is introduced into the inner cavity of the fluidized bed to heat and fluidize the heat storage material in the inner cavity of the fluidized bed.

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