Multi-stage and multi-mode fluidized bed heating system

Abstract

The invention provides a multi-stage and multi-mode fluidized bed heating system, and belongs to the technical field of energy storage devices. The problems that temperature gradient exists when the fluidized bed is heated by multistage resistors, and electromagnetic induction heating dynamic power adjustment cannot be well matched with the complex use condition of the fluidized bed are solved. A multi-stage and multi-mode fluidized bed heating system comprises a heating cavity, a heating plate and a heating coil. The heating cavity comprises a plurality of stages of heating cavities which are distributed in a spatial sequence and are different in heating power, and the heating cavities are used for heating materials entering the heating cavity stage by stage; the cavity wall of the heating cavity is the heating plate; the heating coil is electrically connected with a control unit, and the control unit is used for selecting a heating mode so as to adjust the heating power of the heating plate. The heating cavities of different levels have different heating powers, so that the heating process can be more accurately controlled, and the energy efficiency ratio is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage devices, in particular to a multi-stage and multi-mode fluidized bed heating system. BACKGROUND

[0002] In the field of electric heating of conventional fluidized beds, traditional heating methods face many challenges. When using resistance heating, the structural design is extremely complex. Resistance heating elements need to be carefully laid out to ensure that heat can be uniformly transferred to the materials in the fluidized bed, which not only involves complex circuit design, but also needs to consider the adaptability of the heating element to the fluidized bed cavity, as well as stability and reliability in high-temperature and high-wear environments, making the structure of the entire system cumbersome and difficult to maintain.

[0003] When different types of fluids or different flow rates of the same fluid are heated by electromagnetic induction in a fluidized bed, the corresponding power needs to be set according to the specific working conditions, so that the fluid can be heated to a specified temperature, and it cannot be universal. SUMMARY

[0004] In view of the above problems existing in the prior art, the present application provides a multi-stage and multi-mode fluidized bed heating system to solve the problems of temperature gradient in the existing multi-stage resistance heating fluidized bed and dynamic power adjustment of electromagnetic induction heating that cannot be well adapted to the complex use of the fluidized bed.

[0005] The specific application content is as follows: In a first aspect, the present application provides a multi-stage and multi-mode fluidized bed heating system, comprising a heating cavity, a heating plate and a heating coil; The heating cavity comprises a plurality of temperature rising cavities that are spatially sequentially distributed and have different heating powers, for heating the material entering the heating cavity step by step; The cavity wall of the temperature rising cavity is the heating plate, and the heating plate and the heating coil are spaced apart and oppositely arranged, and the heating plate heats the material under the action of the heating coil; The heating coil is electrically connected with a control unit, and the control unit is used to select a heating mode and adjust the heating power of the heating plate.

[0006] Optionally, at least one of the thickness, cross-sectional area and material of the heating plate in different temperature rising cavities is different, so that the heating plates in different temperature rising cavities have different resistances.

[0007] Optionally, the system further comprises an outer cavity; The outer cavity is arranged outside the heating cavity and communicates with the heating cavity, and is used to store the material to be heated; The heating coil is arranged in the outer cavity, and is used for preheating the material in the outer cavity by using the heat generated by the heating coil.

[0008] Optionally, the wall of the heating cavity and the outer cavity is provided with at least one of a heat preservation layer and a heating layer.

[0009] Optionally, in the vertical direction of the spatial distribution direction of the heating cavity, a gap is arranged between the heating plate and the chamber wall of the heating cavity, and the gap is used to allow the material to flow between the plurality of heating cavities.

[0010] Optionally, the heating cavity is divided into a plurality of heating cavities by a plurality of heating plates, the adjacent gaps are arranged in a staggered manner, and the surface of the heating plate is further provided with a plurality of groups of fin plates for heat transfer.

[0011] Optionally, the heating coil comprises a plurality of coils corresponding to the plurality of heating cavities, and the plurality of coils are independent of each other.

[0012] Optionally, a plurality of groups of heating cavities are arranged, the heating cavities are independently arranged, and the heating cavities are provided with a communication pipeline for communicating adjacent heating cavities.

[0013] According to the technical scheme, the heating cavities are arranged separately, the heating power of each heating area is accurately controlled, the heating cavities are connected through the communication pipeline, and the material can flow smoothly between the heating cavities, thereby avoiding problems such as blockage.

[0014] Optionally, the heating plate comprises a first chamber wall and a second chamber wall arranged oppositely in the arrangement direction of the heating cavities. One end of the first chamber wall is in contact with the chamber wall of the heating cavity, and the other end has a gap with the chamber wall of the heating cavity. One end of the second chamber wall has a gap with the chamber wall of the heating cavity, and the other end has a gap with the second chamber wall of the heating cavity.

[0015] According to the technical scheme, the specific layout of the first chamber wall and the second chamber wall takes into account the requirements of material flow, which not only ensures sufficient contact area, but also leaves necessary channel space.

[0016] Optionally, the resistivity of the heating coil is less than or equal to the resistivity of the heating plate.

[0017] According to the technical scheme, the effective conversion of electric energy into heat energy is ensured, and energy loss is reduced.

[0018] In a second aspect, the present application provides a heating method for the multi-stage and multi-mode fluidized bed heating system. S1: Buffer preheating: The material is passed into the outer cavity to absorb the heat generated by the heating coil for preheating; S2: Step-by-step heating: The material in the outer cavity is made to overflow into the temperature rising cavities which are heated step by step to complete the heating; S3: After the heating is completed, the material is passed out of the fluidized bed through the discharge port.

[0019] Optionally, the heating mode of the heating coil includes a medium frequency induction heating mode, a high-voltage power frequency heating mode, a low-voltage variable frequency heating mode, a high frequency induction heating mode and a pulse heating mode; and the heating coil is further provided with a power regulating module for accurately controlling the heating process.

[0020] By adopting the technical scheme, the flexible and efficient heating solution is provided by including the steps of buffer preheating, step-by-step heating and the like, in combination with various heating modes (such as medium frequency induction heating, high-voltage power frequency heating and the like), and is suitable for the heating requirements of different types of materials. The existence of the power regulating module ensures the accurate controllability of the heating process.

[0021] Compared with the prior art, the present application has the following advantages: The multi-stage and multi-mode fluidized bed heating system provided by the present application can realize step-by-step heating of the material. The temperature rising cavities of different levels have different heating powers, which helps to more accurately control the heating process and improve the energy efficiency ratio; it also helps to set different heating powers according to specific application conditions to ensure heating to the target temperature with less additional energy consumption. The flexible and efficient heating solution is provided by including the steps of buffer preheating, step-by-step heating and the like, in combination with various heating modes (such as medium frequency induction heating, high-voltage power frequency heating and the like), and is suitable for the heating requirements of different types of materials. The existence of the power regulating module ensures the accurate controllability of the heating process. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor.

[0023] Figure 1 The working principle schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the present application is shown; Figure 2 The top view structural schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the present application is shown; Figure 3 The perspective structural schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the present application is shown; Figure 4 Fig. 1 shows a top view of a multi-stage, multi-mode fluidized bed heating system according to an embodiment of the present application; Figure 5 Fig. 2 shows a front view of a multi-stage, multi-mode fluidized bed heating system according to an embodiment of the present application; Figure 6 Fig. 3 shows a structural view of a multi-stage, multi-mode fluidized bed heating system according to an embodiment of the present application; Figure 7 Fig. 4 shows a structural view of a multi-stage, multi-mode fluidized bed heating system according to an embodiment of the present application; Figure 8 Fig. 5 shows a structural view of a multi-stage, multi-mode fluidized bed heating system according to an embodiment of the present application.

[0024] In the drawings, the following reference signs apply: 1, outer cavity; 2, heating cavity; 3, heating coil; 4, temperature rising cavity; 5, heating plate. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way limiting on the application or its applications or uses. Based on the embodiments in the present application, any person skilled in the art, based on the inspiration of the present application or combining the present application with other prior art features, obtains any product same or similar to the present application, which falls within the protection scope of the present application. Also, all other embodiments obtained by the person skilled in the art without carrying out creative labor fall within the protection scope of the present application.

[0026] The specific experimental steps or conditions not mentioned in the embodiments can be carried out according to the conventional experimental steps or conditions described in the prior art in the field. The reagents and other instruments not mentioned by the manufacturer are all conventional reagent products that can be obtained by purchase. In addition, the drawings are only schematic diagrams of the embodiments of the present application, and are not necessarily drawn to scale. The same reference signs in the drawings represent the same or similar parts, and thus repeated description thereof will be omitted. Some block diagrams shown in the drawings are functional entities, which do not necessarily correspond to physically or logically independent entities.

[0027] The techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the specification of the present application under appropriate circumstances.

[0028] In the description of the present application, it should be understood that the use of the words "first", "second" and the like words to qualify parts is merely for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the present application.

[0029] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0030] Before the multi-stage, multi-mode fluidized bed heating system provided by the present application is described in detail, it is necessary to make the following description of the related art: In the field of electric heating of conventional fluidized beds, the traditional heating method faces many challenges. When using resistance heating, the structural design is extremely complex. The resistance heating element needs to be carefully laid out to ensure that the heat can be uniformly transmitted to the material in the fluidized bed, which not only involves complex circuit design, but also needs to consider the adaptability of the heating element to the fluidized bed cavity, as well as the stability and reliability in high temperature and high wear environment, making the structure of the entire system cumbersome and difficult to maintain.

[0031] And if electromagnetic induction heating is used, although there is a certain advantage in heating efficiency, but it comes with the problem of large coil loss. Electromagnetic induction heating relies on the coil to generate an alternating magnetic field, which in turn causes the inductor to generate an induced current and heat. However, in this process, the coil itself will generate a large energy loss due to resistance and alternating magnetic field, which not only reduces the energy utilization efficiency, but also increases the operating cost and maintenance frequency.

[0032] And the heating of the fluid in the fluidized bed, the specific heat capacity of different fluids is different; the same fluid has different flow rates and different flow rates, so electromagnetic heating needs to set different heating powers for different fluids and different flow rates so that the fluid can be heated to a specified temperature.

[0033] The existing multi-stage electromagnetic heating system is mostly heated by multiple groups of coils, and in the actual application of the fluidized bed, there are many problems, such as the distribution of multiple groups of coils in the fluidized bed, the separation of fluid in the fluidized bed, etc.

[0034] In order for those skilled in the art to more clearly understand the present application, the multi-stage, multi-mode fluidized bed heating system described in the present application will now be described in detail through the following embodiments.

[0035] In a first aspect, Figure 1 The working principle schematic diagram of the multi-stage, multi-mode fluidized bed heating system provided by the embodiment of the present application is shown, and the dashed line in the figure is the flow direction of the material;Figure 2 A schematic top view of the structure of a multi-stage, multi-mode fluidized bed heating system provided by an embodiment of the present invention is shown; Figure 3 The perspective structural diagram of the multi-stage, multi-mode fluidized bed heating system provided by the embodiment of the present invention is shown as follows: Figures 1-3 As shown, the embodiment of the present invention proposes a multi-stage, multi-mode fluidized bed heating system, including a heating chamber 2, a heating plate 5 and a heating coil 3; The heating chamber 2 includes several levels of heating chambers 4 with different heating powers and distributed in a spatial order, which are used to heat the material entering the heating chamber 2 step by step; The cavity wall of the heating chamber 4 is the heating plate 5. There is a gap between the heating plate 5 and the heating coil 3, and they are arranged opposite to each other. The heating plate 5 heats the material under the action of the heating coil 3. The heating coil 3 is electrically connected to a control unit, and the control unit is used to select a heating mode and further adjust the heating power of the heating plate.

[0036] The heating chamber 2 is connected to the material to be heated, and the material is transported and heated therein. An insulation layer and a heating layer can be optionally provided to facilitate additional heating and insulation of the material therein, thereby reducing heat loss and ensuring the temperature distribution of the material in the fluidized bed.

[0037] The heating coil 3 is used to generate a magnetic field when energized, thereby heating the heating plate 5 therein. The heating plate 5 is made of metal or inorganic conductive material, etc., so as to form eddy currents inside under the action of the magnetic field and the closed loop, thereby generating heat on the heating plate 5, thereby heating the material. The heating coil 3 and the heating plate 5 can be made of the same material or different materials; according to the operating temperature, the heating coil 3 can be made of metal or inorganic conductive ceramics such as SiC, ZrB2, etc., and can be used in different atmospheres.

[0038] The heating plates 5 can be assembled to form a cavity, and different assembly methods can form isometric or non-isometric cavities. The heating plates 5 are in close contact with the inner wall of the device, thereby separating the interior of the device into small fluidized beds with different heating temperatures. The heating cavities 4 are the heating plates 5 that form a closed loop, and the small cavities formed relative to the overall heating cavity 2 are arranged according to the order of the heating cavities 4 in space. The heating cavities 4 can be divided into low-temperature cavities, medium-temperature cavities, and high-temperature cavities. The greater the temperature difference between the material in the low-temperature cavities and the heating plates 5, the easier the material is heated, the higher the material heating rate, and the higher the heating power required by the heating plates 5. In the medium-temperature cavities and the high-temperature cavities, the temperature difference between the material and the heating plates 5 gradually decreases, the heating rate slows down, and the heating power required by the heating plates 5 also decreases. Therefore, the resistance of the heating plates 5 in different heating cavities 4 can be adjusted to adjust the heating power. The number of different heating cavities 4 is also set, for example, the low-temperature cavities with high heating power and fast heating speed can be set to be fewer, and the number of medium-temperature cavities and high-temperature cavities can be increased as the heating power gradually decreases, to ensure that the heating temperature is reached and the energy efficiency ratio is improved.

[0039] By designing the heating cavity 2, the heating plate 5, and the heating coil 3, the system can realize step-by-step heating of the material. Different levels of heating cavities 4 have different heating powers, which helps to more accurately control the heating process and improve the energy efficiency ratio, and also helps to set different heating powers according to specific application conditions to ensure heating to the target temperature with less additional energy consumption.

[0040] In some embodiments, at least one of the thickness, cross-sectional area, and material of the heating plates 5 in different heating cavities 4 is different, so that the heating plates 5 in different heating cavities 4 have different resistances. Figure 1 As shown in the figure, the magnetic field generated by the heating coil 3 vertically passes through the heating coil 3 upward or downward, and the change of magnetic flux causes the heating plate 5 to generate current in the horizontal direction. The cross-sectional area is the cross-sectional area of the heating plate 5 in the vertical direction.

[0041] By this technical solution, at least one of the thickness, cross-sectional area, or material of the heating plates 5 in different heating cavities 4 is different, to adjust the resistance value, so that the heating power of the heating plates 5 in each heating cavity 4 is different. This method can better adapt to the heating needs of materials at different stages and optimize the entire heating process.

[0042] In this embodiment, according to the use, the inner wall can be regarded as a heating plate 5 to heat the material in the fluidized bed, or the inner and outer walls are made of heat-insulating materials to separate the device into fluidized beds with different temperature distributions, reduce heat loss, and ensure the temperature distribution of the material in the fluidized bed.

[0043] In an embodiment, Figure 1 A working principle schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the present application is shown; Figure 2 A top view structural schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the present application is shown; as Figure 1 and Figure 2 As shown in the embodiment, an outer cavity 1 is further included. The outer cavity 1 is arranged outside the heating cavity 2 and communicates with the heating cavity 2, and is used to store the material to be heated, in combination with Figure 1 As shown in the figure, the dashed line is the flow path direction of the material, the outer cavity 1 is a layer of outer wall arranged outside the heating cavity 2 and the heating coil 3, and a cavity is formed outside the heating cavity 2, the material first enters the outer cavity 1 for preheating, and then enters the heating cavity 2 through the outer cavity 1 for sufficient heating. The heating coil 3 is arranged in the outer cavity 1, and is used to preheat the material in the outer cavity 1 by using the heat generated by itself.

[0044] By adopting the technical scheme, the outer cavity 1 is used to store the material to be heated, and the additional heat generated by the heating coil 3 is used to preheat the material, so that the energy utilization rate of the system is further improved.

[0045] In the embodiment, the wall surface of the heating cavity 2 and the outer cavity 1 is provided with a heat preservation layer and a heating layer, the heating layer can be made of the same material as the heating plate 5 or a different material, and is arranged to form a closed circuit and generate an electric current under a magnetic field to heat.

[0046] By adopting the technical scheme, the heat loss is effectively reduced, further heating is achieved, and the overall heating efficiency is improved.

[0047] In the embodiment, a gap is arranged between the heating plate 5 and the upper and lower chamber walls of the heating cavity 2 in the vertical direction of the spatial distribution direction of the heating cavity 2, and the gap is used to allow the material to flow between the multiple temperature rising cavities 4, as Figure 1 As shown in the figure, the heating cavity 2 is spatially distributed along the positive direction of the Y axis, the upper and lower chamber walls of the heating cavity 2 refer to the top surface and the bottom surface of the heating cavity 2, and the gap is the gap between the heating plate 5 and the top surface and the bottom surface. Among them, the top surface and the bottom surface are the top surface and the bottom surface in the Z axis direction.

[0048] By adopting the technical scheme, the gap between the heating plate 5 and the chamber wall allows the material to flow freely between the multiple temperature rising cavities 4, prolongs the flow path, prolongs the heating time, and promotes uniform heating.

[0049] In the embodiment, the heating cavity 2 is divided into a plurality of the heating cavities 4 by a plurality of the heating plates 5, the adjacent gaps are staggered, and the heating plate 5 is further provided with a plurality of groups of fin plates for heat transfer. Figure 1 As shown in the figure, the heating plate 5 includes two groups, Figure 1 In the embodiment, the left gap of the heating cavity 4 is the inlet, the right gap is the outlet, the left gap is the gap between the heating plate 5 and the bottom surface of the heating cavity 2, and the material flows into from the lower gap; the right gap is the gap between the heating plate 5 and the top surface of the heating cavity 2, and the material flows out from the upper gap, and after flowing down under the action of gravity, continues to enter the inlet of the next group of heating cavities 4.

[0050] By adopting the technical scheme, the gaps of the heating cavities 4 divided by the heating plate 5 are staggered, and the heat transfer fin plates are additionally arranged on the surface, so that the heat transfer area is increased, and the heat transfer effect is enhanced.

[0051] In another embodiment, please refer to Figure 4 and Figure 5 As shown in the figure, Figure 4 The figure shows a top view structural schematic diagram of another embodiment of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the application; Figure 5 The figure shows a front view structural schematic diagram of another embodiment of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the application; as Figure 4 and Figure 5 As shown in the figure, each heating plate 5 is separately matched with a heating coil 3; the heating plate 5 and the heating coil 4 are made of different materials; The heating coil 3 is arranged inside the heating plate 5; the heating plate 5 is in close contact with the outer wall of the equipment, so as to separate different cavities, and the heating coil 3 includes a plurality of coils corresponding to a plurality of heating cavities 4, and the plurality of heating coils 3 are independent of each other.

[0052] By adopting the technical scheme, each heating cavity 4 is matched with an independent heating coil 3, so that the heating power of each heating area can be accurately controlled, and the complex heating requirements can be met.

[0053] In another embodiment, please refer to Figure 6 As shown in the figure, Figure 6 The figure shows a structural schematic diagram of the multi-stage and multi-mode fluidized bed heating system provided by the embodiment of the application; as Figure 6 As shown in the figure, in the embodiment, a plurality of groups of heating cavities 2 can be arranged, the heating cavities 2 are independently arranged, the heating cavities 2 are provided with a communication pipeline for communicating adjacent heating cavities 2; a single heating cavity 4 is arranged in each group of heating cavities 2, and each group of heating cavities 4 is provided with a single heating coil 3.

[0054] According to the technical scheme, the heating cavities 2 are separately arranged in multiple groups, the temperature raising cavities 4 are also separately arranged, the heating power of each temperature raising area is accurately controlled, the heating cavities 2 are connected through the communication pipes, and the smooth flow of the materials between the heating cavities 2 is ensured, so that the problems such as blockage are avoided.

[0055] In yet another embodiment, referring to Figure 7 and Figure 8 , a front view of the heating cavity of the multi-stage and multi-mode fluidized bed heating system is shown. Figure 7 Figure 8 A perspective structural schematic view of the heating cavity of the multi-stage and multi-mode fluidized bed heating system is shown, as shown in Figure 7 and Figure 8 , the heating plate 5 includes the oppositely arranged first cavity wall 51 and second cavity wall 52 in the arrangement direction of the temperature raising cavity 4. The one end of the first cavity wall 51 is in contact with the bottom cavity wall of the heating cavity 2, and the other end has a gap with the top cavity wall of the heating cavity 2. The one end of the second cavity wall 52 has a gap with the bottom cavity wall of the heating cavity 2, and the other end has a gap with the top cavity wall of the heating cavity 2.

[0056] In the embodiment, as shown in Figure 7 , the second cavity wall 52 also has a gap with the top wall of the heating cavity 2, and the gap between the second cavity wall 52 and the top cavity wall is smaller than the gap between the first cavity wall 51 and the top cavity wall, so that the direction of the material flowing out of the outlet is towards the next group of heating cavities 2 on the right side in the figure.

[0057] According to the technical scheme, the specific layout of the first cavity wall 51 and the second cavity wall 52 takes into account the requirements of the material flow, as shown in Figure 7 , the material flows in from the gap below the left side of the temperature raising cavity 4 in the figure and flows out from the gap above the right side of the temperature raising cavity 4 in the figure, so that the gravity is fully utilized, sufficient contact area is ensured, and necessary channel space is left.

[0058] In the embodiment, as shown in Figure 7 , the heating coil 3 generates a magnetic field while heating the material in the temperature raising cavity 4 through self-heating, that is, the resistance heating + electromagnetic induction heating mode is adopted. According to the technical scheme, the heating coil undertakes two functions at the same time, and the resistance heating element and the electromagnetic heating device do not need to be separately arranged; the equipment volume is reduced, the equipment integration is improved, and the heating efficiency is improved.

[0059] In the embodiment, the resistivity of the heating coil is less than or equal to the resistivity of the heating plate. ​

[0060] Adopting the technical scheme, the heating coil 3 generates a changing magnetic field, and the heating plate 5 in the magnetic field generates a current to heat the heating plate 5 itself, thereby heating the material, and therefore the resistivity of the heating coil 3 is set to be less than the resistivity of the heating plate 5, so that the effective conversion of electric energy into heat energy is ensured, and energy loss is reduced.

[0061] In still another embodiment, as shown in Figure 8 The heating plate 5 is powered to heat the material in a resistance heating mode, and the heating plate 5 of the heating cavity 4 in different heating cavities 2 is provided with different resistances and heating powers.

[0062] Adopting the technical scheme, resistance heating is used, which is simple to set and has lower cost; by setting different resistances and heating powers, efficient and stable heating during the temperature rising process is ensured.

[0063] In still another embodiment, as shown in Figures 6-8 As shown in Figure 8 The heating plate 5 of the heating cavity 2 corresponding to a lower heating temperature is provided with a resistance heating heating plate 5 as shown in Figure 6 and 7 The heating plate 5 of the heating cavity 2 corresponding to a higher temperature is provided with a combination of electromagnetic induction heating and resistance heating as shown in

[0064] Adopting the technical scheme, resistance heating is used in the low-temperature region, and for the heating cavity 2 required to be heated at a lower temperature, resistance heating can meet the requirements, and has moderate heating rate, simple control and lower energy consumption; composite heating is used in the high-temperature region, and when a higher temperature is required, resistance heating has low efficiency and slow temperature rising, while electromagnetic induction heating has the advantages of fast temperature rising and fast thermal response. The combination of the two can ensure high efficiency while realizing stable temperature control. In the low-temperature region, excessive heating needs to be avoided, and if electromagnetic induction heating is used in all heating cavities 2, local overheating in the low-temperature region may occur, affecting the quality of the material or the stability of the equipment; in the high-temperature region, the uniformity of heat and the response speed are enhanced, electromagnetic induction heating can provide faster and more concentrated energy input, and combined with resistance heating to maintain a constant basic temperature, it helps to reduce heat fluctuation and improve the stability of the system.

[0065] As shown in Figure 1 The dashed line in the figure is the flow direction of the material; the embodiment of the application also provides a heating method for the multi-stage and multi-mode fluidized bed heating system, comprising the following steps: S1: buffering and preheating: the material is passed into the outer cavity 1 to absorb heat generated by the heating coil 3 for preheating; S2: step-by-step heating: the material in the outer cavity 1 is made to flow into the temperature rising cavities 4 for heating by overflow; S3: after the heating is completed, the material is discharged from the fluidized bed through the discharge port.

[0066] In Figure 3 , Figure 4 and Figure 5 embodiments shown, the material flows into the independent heating cavity 2, and completes the stage heating under the heating of the heating coil 3 and the heating cavity 4, and then enters the next stage heating cavity 2 through the connecting pipeline to perform the subsequent heating.

[0067] In Figure 6 and Figure 7 embodiments shown, the material flows into the independent heating cavity 2, and completes the stage heating under the heating of the heating coil 3 and the heating cavity 4, and then enters the next stage heating cavity 2 through the connecting pipeline to perform the subsequent heating.

[0068] In Figure 8 embodiments shown, the material flows into the independent heating cavity 2, and completes the stage heating under the heating of the heating coil 3 and the heating cavity 4, and then enters the next stage heating cavity 2 through the connecting pipeline to perform the subsequent heating.

[0069] In the embodiment, the heating mode of the heating coil 3 includes the medium-frequency induction heating mode, the high-voltage power frequency heating mode, the low-voltage variable frequency heating mode, the high-frequency induction heating mode and the pulse heating mode; the heating coil 3 is further provided with a power regulating module for accurately controlling the heating process; in the embodiment, the fluidized bed equipment can be used in series and in parallel; the heating coil 3 in the fluidized bed can adopt the high-voltage power frequency, the low-voltage medium / high frequency with gear power regulating, the stepless power regulating mode and the like.

[0070] By adopting the technical solution, the heating mode can be flexibly switched according to the characteristics (conductivity, magnetic permeability, particle size and the like) of different materials, and the heating efficiency and uniformity are improved. In combination with the power regulating module, the stepless or gear type power regulation is realized, and the control ability on the heating rate and the constant temperature precision is enhanced. For example, the medium / high frequency is used for rapid heating, the pulse heating is used for preventing local overheating, and the high-voltage power frequency is used for high-power stable heating.

[0071] In the embodiment, the outer wall surface of the equipment and the inner wall surface of the equipment form a cavity (the outer cavity 1), the heating coil 3 is installed in the cavity, and the material is first heated in the cavity to recover the heat of the heating coil 3; the heating coil 3 is electrified to form a changing magnetic field, so that the heating plate 5 generates heat under the action of the magnetic field, thereby heating the material.

[0072] By adopting the technical solution, the heating coil 3 is arranged in the outer cavity 1 formed by the outer wall surface of the equipment and the inner wall surface of the equipment, so that the material is preheated before entering the main heating area; the lost heat generated during the operation of the heating coil 3 is recovered to realize energy recycling; the alternating magnetic field generated by the heating coil 3 makes the heating plate 5 generate heat by induction, thereby further heating the material and improving the overall thermal efficiency.

[0073] In the embodiment, the inner wall of the device and the heating plate 5 form different heating cavities 4, each of which corresponds to a different working temperature; each heating cavity 4 is interconnected, and the material enters the heating cavity 4 from the outer cavity 1; the material can smoothly pass through the different heating cavities 4 through the height difference between the heating cavities.

[0074] According to the technical solution, each heating cavity 4 can be set to different temperatures to realize stepwise heating; the material flows through each heating cavity in turn to ensure sufficient heating; the material receives different intensities of heating at different stages to avoid local overheating or non-heating; the number of heating cavities can be increased or decreased according to the production capacity demand, which is suitable for industrialization.

[0075] In the embodiment, the material flows between different heating cavities 4 by overflow, so different cavities can be set to different or the same heights.

[0076] According to the technical solution, the material flows naturally by gravity and height difference, reducing the complexity of the device; the feeding and discharging can be synchronized, which is suitable for continuous production; the overflow method is not easy to cause material accumulation, especially for powder or granular materials; different residence times and temperature distributions can be achieved by adjusting the heights of the cavities.

[0077] The system operation principle is shown in Figure 1 . The material enters the outer cavity 1; the heating coil 3 generates a changing magnetic field while generating heat to heat the material; The height of the outer cavity 1 is greater than or equal to the height of the heating cavity 2 (the height of the inner wall of the device is lower than or equal to the height of the outer wall of the device); the material in the outer cavity 1 can enter the heating cavity 2 by overflow, that is, the height of one side of the inner wall of the device (close to the low-temperature side of the heating cavity 2) is lower than the height of the outer wall of the device; The heating plate 5 in the heating cavity 2 generates heat under the action of the magnetic field to heat the fluidized bed material; according to different working temperatures, the heating cavity 2 can be divided into different heating cavities 4; as shown in Figure 1 , the material flows from left to right, and the temperature distribution is from the low-temperature zone to the high-temperature zone; the greater the temperature difference between the material and the heating plate 5, the easier the material is heated, so fewer low-temperature zone cavities can be set; for the area where the temperature difference between the material and the heating plate 5 is small, the height / material / thickness of the heating body can be adjusted to strengthen the heat transfer effect.

[0078] The material leaves the fluidized bed heater through the discharge port provided in the heating cavity 4.

[0079] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in the specification.

[0080] For the method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should know that the present application is not limited by the order of the described actions, because according to the present application, certain steps can be performed in other order or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification are all preferred embodiments, and the actions and components involved are not necessarily necessary for the present application.

[0081] The above describes in detail the multi-stage and multi-mode fluidized bed heating system provided by the present application, and the principles and implementation manners of the present application are described by applying specific examples. The above embodiment description is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation manner and application range will have changes, and the above description should not be understood as a limitation of the present application.

Claims

1. A multi-stage, multi-mode fluidized bed heating system, characterized in that: It comprises a heating chamber (2), a heating plate (5) and a heating coil (3); The heating chamber (2) comprises a plurality of levels of temperature-raising chambers (4) distributed in a spatial sequence and having different heating powers, for heating the material entering the heating chamber (2) step by step; The cavity wall of the temperature-raising cavity (4) is the heating plate (5), and there is a gap between the heating plate (5) and the heating coil (3), and the heating plate (5) and the heating coil (3) are arranged relative to each other. The heating plate (5) heats the material under the action of the heating coil (3); The heating coil (3) is electrically connected to a control unit, and the control unit is used to select a heating mode and thereby adjust the heating power of the heating plate (5).

2. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: At least one of the thickness, cross-sectional area and material of the heating plates (5) located in different heating chambers (4) is different, so that the heating plates (5) located in different heating chambers (4) have different resistances.

3. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: The system further comprises an outer chamber (1); The outer chamber (1) is arranged outside the heating chamber (2) and is connected to the heating chamber (2), and is used to store materials that need to be heated; The heating coil (3) is arranged in the outer cavity (1) and is used to preheat the material in the outer cavity (1) by utilizing its own heat.

4. The multi-stage, multi-mode fluidized bed heating system according to claim 3, characterized in that: The walls of the heating cavity (2) and the outer cavity (1) are provided with at least one of a heat-insulating layer and a heating layer.

5. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: In a direction perpendicular to the spatial distribution direction of the heating chamber (2), a gap is provided between the heating plate (5) and the chamber wall of the heating chamber (2), and the gap is used to allow material to flow between the plurality of temperature-raising chambers (4).

6. The multi-stage, multi-mode fluidized bed heating system according to claim 5, characterized in that: The heating chamber (2) is divided into a plurality of temperature-raising chambers (4) by a plurality of heating plates (5), and adjacent gaps are arranged in a staggered manner. The surfaces of the heating plates (5) are also provided with a plurality of groups of fins for heat transfer.

7. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: The heating coil (3) comprises coils corresponding to the plurality of temperature-raising chambers (4), respectively, and the plurality of coils are independent of each other.

8. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: The heating chambers (2) can be arranged in multiple groups, and the heating chambers (2) are independently arranged. The heating chambers (2) are provided with connecting pipes for connecting adjacent heating chambers (2).

9. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: The heating plate (5) comprises a first chamber wall (51) and a second chamber wall (52) arranged opposite to each other in the arrangement direction of the temperature rising chamber (4); One end of the first chamber wall (51) is in contact with the chamber wall of the heating chamber (2), and a gap exists between the other end and the chamber wall of the heating chamber (2); There is a gap between one end of the second chamber wall and the chamber wall of the heating chamber (2), and there is a gap between the other end of the second chamber wall and the second chamber wall (52) of the heating chamber (2).

10. The multi-stage, multi-mode fluidized bed heating system according to claim 1, characterized in that: The resistivity of the heating coil (3) is less than or equal to the resistivity of the heating plate (5).

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