Demagnetizing machine with drying system and control method thereof

Abstract

The invention discloses a demagnetizing machine with a drying system and a control method of the demagnetizing machine. The demagnetizing machine comprises a sealing shell (13) and a plurality of coils (7) installed in the sealing shell, a material channel (2) is arranged in the middle of the sealing shell, a screen (1) is installed in the material channel, an oil inlet (10) and an oil outlet (11) are formed in the sealing shell, a cooling channel (14) filled with heat conduction oil is arranged between the sealing shell and the coils, and the cooling channel (14) is communicated with the oil inlet (10) and the oil outlet (11). A flow guide channel is arranged between the cooling channel and the material channel, the oil inlet, the cooling channel, the flow guide channel and the oil outlet are sequentially communicated, and the oil inlet is communicated with a conveying oil pump (F101) through a first oil guide pipe (G301). The material drying system is integrated, and waste heat generated by the demagnetizer system can be effectively utilized to achieve material drying.

Description

Technical Field

[0001] The invention relates to a demagnetizer, in particular to a demagnetizer with a drying system and a control method thereof. Background Art

[0002] The processing and preparation of negative electrode materials is an important part of the lithium battery industry, and the quality of the finished negative electrode materials has a significant impact on the performance, service life, safety and stability of lithium battery products. In comparison, the impact of the magnetic impurity content in the negative electrode material on the performance, service life and safety and stability of lithium battery products is more prominent, because the magnetic impurity particles in the negative electrode material may pierce the battery diaphragm during the charging and discharging process of the lithium-ion battery, causing an internal short circuit in the battery, thereby causing rapid self-discharge, affecting the safety performance of the battery, and seriously reducing the service life of the battery. Therefore, the demagnetization process to reduce the magnetic impurities in the negative electrode material is an essential step in the processing of negative electrode materials.

[0003] The key equipment used in the demagnetization process is the demagnetizer, which intermittently generates a magnetic field in the screen through the principle of electromagnetism to separate the target components and magnetic impurities in the negative electrode material, thereby improving the purity and quality of the negative electrode material. The degree of agglomeration of the material has a decisive influence on the demagnetization ability of the demagnetizer, and the water content of the material is one of the key factors affecting the degree of agglomeration of the material. Therefore, reducing the water content of the material is very necessary to improve the demagnetization effect of the negative electrode material.

[0004] As shown in Chinese patent CN117920572A, the traditional demagnetizer includes an electromagnetic body, a cylinder, a material channel, a screen, a separation valve in the form of a three-way assembly, and a frame. The material enters the demagnetizer through the feed end of the material channel, passes through the screen to separate the magnetic impurities from the non-magnetic material, and then leaves the demagnetization system through the discharge end of the material channel. Obviously, this demagnetizer does not have a material drying system. When in use, the material itself contains a certain amount of moisture, and there are more non-dry surfaces and areas in the demagnetizer. These surfaces and areas contain higher moisture, which further increases the moisture content of the material entering the demagnetizer. Excessive moisture content in the material will cause the target component to agglomerate with the magnetic impurities and adhere to the screen structure when the material passes through the screen, resulting in a reduction in the screen flow area, which in turn leads to a reduction in the material flow rate, the system demagnetization capacity, and the yield, greatly affecting the demagnetization performance.

[0005] At present, some demagnetizers also use an external independent drying system to dry the material, that is, a set of independent drying equipment is added in front of or above the demagnetizer equipment. The material is first dried by the drying equipment and then enters the demagnetizer system for demagnetization. However, in this case, the material channel, screen and separation valve of the demagnetizer body are still non-drying surfaces and areas. The moisture on these surfaces and areas will increase the moisture content of the material entering the demagnetizer, and these external drying equipment are often large in size and require a certain amount of installation space, which increases the space resource load of the production line platform. What's more, an independent drying system means a sharp increase in equipment costs.

[0006] In addition, the independent drying system fails to utilize the waste heat resources generated by the demagnetizer itself and can only realize its functions by consuming other energy sources, which increases energy costs. At the same time, the increase in equipment leads to increased system complexity, and the failure rate increases, resulting in higher maintenance costs. As the number of objects contacted by the material increases, the amount of material retained due to van der Waals forces or electrostatic forces will also increase, resulting in a decrease in yield. Summary of the invention

[0007] The technical problem to be solved by the present invention is that, in view of the deficiency that the existing demagnetizer cannot fully dry the material, the present invention provides a demagnetizer and a control method thereof which can utilize the waste heat of the demagnetizer to dry the material.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A demagnetizer with a drying system comprises a sealed shell and a plurality of coils installed in the sealed shell, a material channel is provided in the middle of the sealed shell, a screen is installed in the material channel, an oil inlet and an oil outlet are provided on the sealed shell, a cooling channel filled with heat transfer oil is provided between the sealed shell and the coil, a guide channel is provided between the cooling channel and the material channel, the oil inlet, the cooling channel, the guide channel and the oil outlet are connected in sequence, and the oil inlet is connected to an oil delivery pump via a first oil guide pipe.

[0010] In this way, the present invention integrates a drying system inside the sealed housing of the demagnetizer, and converts the waste heat generated by the demagnetizer coil into a heat source for the drying system. Specifically, the present invention combines a heat transfer oil circuit system formed by a sequentially connected oil delivery pump, an oil inlet, a cooling channel, a flow guide channel, and an oil outlet with a material channel, and utilizes the high-temperature oil formed by the collected coil waste heat to flow through the flow guide channel outside the material channel, and directly transfers the waste heat to the material channel, thereby heating the screen and the material, thereby achieving drying of the material. This design not only saves space resources, reduces energy costs, simplifies the system, reduces maintenance costs, but also improves the demagnetization effect.

[0011] Preferably, a supplementary heating module is installed in the diversion channel, and the supplementary heating module includes an auxiliary heating coil, which is connected to a periodically changing current and generates a changing magnetic field, and the direction of the magnetic field generated by the auxiliary heating coil is the same as the direction of the magnetic field generated by the coil. In this way, the present invention can also use the induction supplementary heating module to directly heat the material channel, screen, screen shaft and other structures in contact with the material, reduce the non-dry surface and area in the material channel, further reduce the moisture content of the material, and enhance the dispersion of the material; at the same time, the supplementary heating module can generate an oscillating magnetic field in the same direction as the coil magnetic field, which can further strengthen the central magnetic field strength, improve the adsorption capacity of magnetic impurities, and further improve the demagnetization effect.

[0012] Preferably, the guide channel includes a first guide channel and a second guide channel, the cooling channel, the first guide channel, the second guide channel and the oil outlet are connected in sequence, and the auxiliary heating coil is installed in the second guide channel.

[0013] Preferably, a first sensor for detecting the temperature of the auxiliary heating module is installed in the second flow guiding channel.

[0014] Preferably, a second sensor for detecting the temperature of the material channel is installed in the material channel.

[0015] Preferably, the oil outlet is connected to the heat medium inlet of the heat exchanger via the second oil guide pipe, and the oil delivery pump is connected to the refrigerant outlet of the heat exchanger to fully utilize the waste heat.

[0016] Preferably, the sealed housing is also provided with an oil filling port so as to fill the sealed housing with heat transfer oil before the demagnetizer is started.

[0017] Based on the same inventive concept, the present invention also provides a control method for the demagnetizer, which comprises the following steps:

[0018] Start the oil pump, and the heat transfer oil will continue to flow into the oil inlet, cooling channel, heat transfer channel, material channel in sequence through the oil pump, and then flow out from the oil outlet. At the same time, the coil is energized to generate a background magnetic field at the screen.

[0019] When the material channel temperature is monitored to meet the preset standard, the material channel starts to feed, otherwise the supplementary heating module is turned on, and the material feeding is started after the material channel temperature reaches the preset standard;

[0020] The material continuously enters the screen from the feed end of the material channel, and is dried by the waste heat collected by the heat transfer oil and / or the induction heat generated on the screen after the auxiliary heating coil is energized. At the same time, it is demagnetized by the magnetic field generated in the screen. Finally, the material is dried and demagnetized and discharged from the discharge end of the material channel.

[0021] Preferably, the preset standard of the material channel temperature is 100-150°C.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1) The present invention adds a drying system that utilizes waste heat for heating and an induction heating screen to the demagnetization system to heat the material channel, the screen and other structures that are in main contact with the material, thereby reducing the non-drying surface and area in the material channel, reducing the degree of agglomeration of the material due to excessive moisture, reducing the moisture content in the material, enhancing the dispersion of the material, and improving the flow effect and demagnetization effect of the demagnetization system.

[0024] 2) The present invention combines structures or systems such as a heat transfer oil circuit system, a coil, and a material channel, and designs a heat transfer oil circuit flow area on the periphery of the material channel, so that high-temperature oil flows out through the oil circuit on the periphery of the material channel, thereby utilizing the waste heat of the demagnetization system to heat the material channel and the material in the material channel, thereby reducing energy costs.

[0025] 3) The present invention combines the heat transfer oil circuit system and the material channel, that is, the heat transfer oil circuit system is designed between the material channel and the coil as the oil outlet of the high-temperature oil, so that the material channel is heated to 60-100°C under the action of the high-temperature oil, and the material channel then transfers the heat to the screen and the material, thereby heating and drying the material; at the same time, since the temperature of the heat transfer oil in the initial feeding and demagnetization stage is relatively low, the drying effect at this time is unstable, so a group of supplementary heat modules are designed between the material channel and the coil. The supplementary heat modules are composed of an induction heating system, and the supplementary heat modules directly act on the material channel and the screen to realize the supplementary heat function of the material channel. During the entire demagnetization process, the supplementary heat modules work intermittently to ensure the continuous operation of the drying function. In addition, the auxiliary heat coil of the supplementary heat module can generate a magnetic field in the same direction as the coil magnetic field, which increases the final magnetic field strength in the screen, thereby improving the demagnetization effect.

[0026] 4) The scheme of the present invention adopts an integrated method to save installation space resources, and the system is simple and the maintenance cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic diagram of the structural cross-section of the present invention.

[0029] Figure 2 It is the work flow chart of the present invention.

[0030] In the figure: 1-screen, 2-material channel, 201-feed end, 202-discharge end, 3-screen shaft, 4-first flow guide channel, 5-auxiliary heating coil, 6-second flow guide channel, 7-coil, 8-first sensor, 9-second sensor, 10-oil inlet, 11-oil outlet, 12-oil filling port, 13-sealed housing; 14-cooling channel; F101-oil delivery pump, F102-heat exchanger, G301-first oil guide pipe, G302-second oil guide pipe. DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0032] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] See also Figure 1 An embodiment of a demagnetizer with a drying system of the present invention is mainly composed of a drying demagnetization system and a pumping cooling system, wherein the drying demagnetization system is mainly composed of a screen 1, a material channel 2, a feed end 201, a discharge end 202, a screen shaft 3, an auxiliary heat coil 5, an oil isolation channel 1, a first flow guide channel 4, a second flow guide channel 6, a coil 7, a first sensor 8, a second sensor 9, an oil inlet 10, an oil outlet 11, an oil filling port 12, a sealed shell 13, etc.; the pumping cooling system is mainly composed of an internal heat conduction oil circuit of the demagnetizer, an oil delivery pump F101, a heat exchanger F102, a first flow guide pipe G301 and a second flow guide pipe G302.

[0035] A plurality of coils 7 are installed in the sealed housing 13, and cooling channels 14 filled with heat transfer oil are arranged between the coils 7 and between the coils and the sealed housing 13. A material channel 2 is arranged in the middle of the sealed housing 13, and the upper end of the material channel 2 is arranged as a feed end 201, and the lower end is arranged as a discharge end 202. A screen 1 and a screen shaft 3 for adsorbing magnetic materials are installed in the material channel 2.

[0036] An oil inlet 10, an oil outlet 11 and an oil filling port 12 are arranged on the sealed shell 13, and a guide channel is arranged between the cooling channel 14 and the material channel 2, and the guide channel includes a first guide channel 4 and a second guide channel 6 arranged from the outside to the inside, and the oil inlet 10, the cooling channel 14, the first guide channel 4, the second guide channel 6, and the oil outlet 11 are connected in sequence, and a heat supplement module is installed in the second guide channel 6, and the heat supplement module includes an auxiliary heat coil 5, and the auxiliary heat coil 5 is connected to a periodically changing current and generates a changing magnetic field, and the direction of the magnetic field generated by the auxiliary heat coil 5 is the same as the direction of the magnetic field generated by the coil 7, the oil inlet 10 is connected to the oil delivery pump F101 through the first oil guide pipe G301, the oil outlet 11 is connected to the heat medium inlet of the heat exchanger F102 through the second oil guide pipe G302, and the oil delivery pump F101 is connected to the refrigerant outlet of the heat exchanger F102.

[0037] In order to facilitate temperature monitoring, a first sensor 8 for detecting the auxiliary heating temperature is installed in the second guide channel 6, and a second sensor 9 for detecting the material channel temperature is installed in the material channel 2.

[0038] Working principle of the present invention: Based on the demagnetization technology of the traditional demagnetizer, the present invention sets a cooling channel 14 filled with heat transfer oil between the sealed shell 13 and the coil 7 and between adjacent coils, and sets a first guide channel 4 and a second guide channel 6 in sequence from the outside to the inside on the periphery of the material channel 2. The cooling channel 14, the first guide channel 4, and the second guide channel 6 are connected in sequence, so that the heat transfer oil circuit system in the demagnetization system and the material channel 2 are combined. Not only is an oil circuit designed between the material channel 2 and the coil 7 as an oil outlet circuit for high-temperature oil, but the material channel 2 is also heated to 60-100°C under the action of the high-temperature oil, and the material channel 2 then transfers the heat to the screen 1 and the material , thereby playing the role of preheating the material; at the same time, since the temperature of the heat transfer oil in the initial feeding and demagnetization stage is low, the material drying effect is unstable at this time, so a group of supplementary heating modules are designed between the material channel 2 and the coil 7, and the auxiliary heating coil of the supplementary heating module is connected to the periodic changing current and generates a changing magnetic field, and the direction of the magnetic field generated by the auxiliary heating coil is the same as the magnetic field generated by the coil, so that the total magnetic field in the material channel 2 changes periodically, and then an induced current is generated in the screen 1, and it is heated, that is, the heating effect generated by the supplementary heating module directly acts on the screen 1, so that the final working temperature of the material channel 2 and the screen 1 is 100-150°C, realizing the drying and heating function of the material and the screen 1. In this way, the present invention adopts an integrated method to solve the drying problem of non-dry surfaces and areas in materials and material channels, which can save installation space resources, and the system is simple and has low maintenance costs. It not only realizes the utilization of waste heat from the demagnetization system and reduces energy costs, but also reduces non-dry surfaces and areas in the material channel 2 under the action of heating, reduces the moisture content in the material, and enhances the dispersion of the material. At the same time, under the action of the auxiliary heating coil 5, the overall magnetic field is enhanced. Under the action of the drying effect and the magnetization effect, the demagnetization effect of the demagnetization system is improved.

[0039] like Figure 2As shown, the process of the present invention starts with the opening of the oil filling port 12, so that the external heat transfer oil flows into the demagnetization oil circuit system (cooling channel 14). After the oil volume reaches the standard, the oil filling port 12 is closed, and the pumping cooling system is started at the same time, and the heat transfer oil enters the delivery oil pump F101. Subsequently, the heat transfer oil continues to flow under the action of the delivery oil pump F101, and enters the cooling channel 14 in the sealed housing 13 through the first oil guide pipe G301. In the cooling channel 14, the heat transfer oil absorbs the heat generated by the coil 7 due to its resistance, and flows through the first guide channel 4 and the second guide channel 6 in turn. At this time, the high-temperature heat transfer oil contacts the material channel 2 and transfers the heat to the material channel 2 to play a heating role. When the cooling oil flows through the second guide channel 6 and is full, it enters the second oil guide pipe G302 through the oil outlet 11. Then, the high-temperature oil enters the heat exchanger F102 for cooling to generate low-temperature cooling oil. At the same time, the coil 7 is energized to generate a background magnetic field at the screen 1, and resistance heat is generated in the coil 7. The heat-conducting oil after absorbing heat heats the material channel 2, and the material channel 2 transfers the heat to the screen 1. If the second sensor 9 detects that the temperature meets the preset standard, the material channel 2 starts to be fed; otherwise, the supplementary heat module is turned on, that is, an oscillating current in the same direction as the coil 7 is passed to the auxiliary coil 5, and the auxiliary coil 5 will generate a positive changing magnetic field in the same direction as the coil 7 in the screen 1, and the screen 1 will generate an induced current and induced heat under the action of the positive changing magnetic field, until the material channel temperature reaches the preset standard, and then the feeding begins. The material continues to enter from the feed end 201 of the material channel 2, and the material is discharged through the discharge end 202 after the material is dried and demagnetized.

[0040] The above is only a specific implementation scheme of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the art can make many possible changes and modifications to the technical scheme of the present invention by using the technical content disclosed above without departing from the scope of the technical scheme of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical scheme of the present invention should fall within the protection scope of the technical scheme of the present invention.

Claims

1. A demagnetizer with a drying system, comprising a sealed housing (13) and a plurality of coils (7) installed in the sealed housing, wherein a material channel (2) is provided in the middle of the sealed housing, and a screen (1) is installed in the material channel, characterized in that: An oil inlet (10) and an oil outlet (11) are provided on the sealed housing; a cooling channel (14) filled with heat-conducting oil is provided between the sealed housing and the coil; a flow guide channel is provided between the cooling channel and the material channel; the oil inlet, the cooling channel, the flow guide channel and the oil outlet are connected in sequence, and the oil inlet is connected to an oil delivery pump (F101) via a first oil guide pipe (G301).

2. The demagnetizer with a drying system according to claim 1, characterized in that: A heat supplement module is installed in the guide channel, the heat supplement module comprising an auxiliary heat coil (5), the auxiliary heat coil is connected to a periodically changing current and generates a changing magnetic field, and the direction of the magnetic field generated by the auxiliary heat coil is the same as the direction of the magnetic field generated by the coil.

3. The demagnetizer with a drying system according to claim 2, characterized in that: The flow guide channel comprises a first flow guide channel (4) and a second flow guide channel (6); the cooling channel, the first flow guide channel, the second flow guide channel and the oil outlet are connected in sequence; and the auxiliary heating coil is installed in the second flow guide channel.

4. The demagnetizer with a drying system according to claim 3, characterized in that: A first sensor (8) for detecting the auxiliary heating temperature is installed in the second flow guiding channel.

5. The demagnetizer with a drying system according to claim 3, characterized in that: A second sensor (9) for detecting the temperature of the material channel is installed in the material channel.

6. The demagnetizer with a drying system according to claim 1, characterized in that: The oil outlet is connected to the heat medium inlet of the heat exchanger (F102) through the second oil guide pipe (G302), and the oil delivery pump is connected to the refrigerant outlet of the heat exchanger.

7. The demagnetizer with a drying system according to claim 1, characterized in that: The sealed housing is also provided with an oil filling port (12).

8. A control method for a demagnetizer according to any one of claims 2 to 7, characterized in that: The following steps are involved: Start the oil pump, and the heat transfer oil will continue to flow into the cooling channel, heat transfer channel, and material channel in sequence through the oil pump, and then flow out from the oil outlet. At the same time, the coil is energized to generate a background magnetic field at the screen. When the material channel temperature is monitored to meet the preset standard, the material channel starts to feed, otherwise the supplementary heating module is turned on, and the material feeding is started after the material channel temperature reaches the preset standard; The material continuously enters the screen from the feed end of the material channel, and is dried by the waste heat collected by the heat transfer oil and / or the induction heat generated on the screen after the auxiliary heating coil is energized. At the same time, it is demagnetized by the magnetic field generated in the screen. Finally, the material is dried and demagnetized and discharged from the discharge end of the material channel.

9. The control method of the demagnetizer according to claim 8, characterized in that: The preset standard of the material channel temperature is 100-150°C.

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