Method and equipment for separating magnetic substances from silicon-based negative electrode materials

Abstract

The present invention provides a method and device for separating magnetic substances in silicon-based negative electrode materials. The method for separating magnetic substances in silicon-based negative electrode materials of the present invention comprises the following steps: S1, obtaining powder to be separated; S2, crushing the powder by airflow blowing; S3, separating the magnetic substance in the powder by electromagnetic adsorption; S4, obtaining the separated powder, and circulating S2 and S3 to separate and process the powder multiple times. The method for separating magnetic substances in silicon-based negative electrode materials of the present invention can completely eliminate the agglomeration phenomenon in the powder, expose the magnetic substances, improve the effective adsorption rate of the magnetic substances, and further improve the accuracy of quantitative analysis and testing of magnetic substances.

Description

Technical Field

[0001] The present invention relates to the technical field of battery safety assessment, and in particular to a method for separating magnetic substances in silicon-based negative electrode materials. The present invention also relates to a separation device for implementing the separation method. Background Art

[0002] In lithium battery production, magnetic foreign matter in electrode materials will affect the thermal stability and consistency of lithium batteries. Excessive content of magnetic foreign matter will reduce the safety performance of the battery. At present, when testing the magnetic foreign matter in electrode materials, based on the characteristics of electrode materials (silicon-based negative electrode powder) such as lipophilicity and hydrophobicity, easy agglomeration and low density, magnetic substances are generally extracted and processed from silicon-based negative electrode powder by magnetic separation, and then the magnetic substances are quantitatively analyzed and tested.

[0003] The existing magnetic separation method is generally: fully disperse the silicon-based negative electrode powder in a prefabricated dispersion system to fully expose the magnetic foreign matter, and then use a magnetic rod to absorb the magnetic foreign matter to achieve the purpose of separating the magnetic foreign matter from the negative electrode powder.

[0004] However, the existing prefabricated dispersion systems mostly use conventional dispersion systems composed of pure water, ethanol and NMP (N-methylpyrrolidone). The interaction force between silicon-based negative electrode powder particles is mainly gravity, and the agglomeration phenomenon is significant. Some magnetic foreign matter is not completely exposed. The effective adsorption rate during magnetic separation is low, and the dispersion effect is biased, resulting in inaccurate subsequent test results. In addition, the magnetic substances separated by the above method will also produce a large amount of suspended waste liquid with high treatment costs during the testing process, and the testing cost is high. Summary of the invention

[0005] In view of this, the present invention aims to propose a method for separating magnetic substances in silicon-based negative electrode materials, so as to effectively separate and extract the magnetic substances and improve the accuracy of quantitative analysis and testing of the magnetic substances.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A method for separating magnetic substances from silicon-based negative electrode materials comprises the following steps:

[0008] S1, obtaining powder to be separated;

[0009] S2, crushing the powder by blowing air;

[0010] S3, separating the magnetic substance in the powder by electromagnetic adsorption;

[0011] S4, obtaining the separated powder, and circulating S2 and S3 to separate and process the powder multiple times.

[0012] Furthermore, the following steps are included: S5, respectively collecting and storing the powder and the magnetic substance after multiple separation treatments in S4 to obtain a powder collection system and a magnetic substance collection system.

[0013] Furthermore, the following steps are included between S4 and S5: S401, washing the magnetic material after multiple separation treatments in S4 with a cleaning agent; the powder collection system includes the solid powder and the powder dispersed in the cleaning agent.

[0014] Furthermore, step S402 is also included between S401 and S5: eliminating the electromagnetic adsorption operation on the magnetic substance, and infiltrating the magnetic substance with the cleaning agent to obtain the cleaning agent that disperses the magnetic substance to obtain the magnetic substance collection system; and / or the cleaning agent includes at least one of ethanol and pure water.

[0015] Furthermore, in S4, when the separated powder obtained reaches a circulation threshold, S2 and S3 are circulated; and / or, the ambient humidity in S1 to S4 is below 40%.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The method for separating magnetic substances in silicon-based negative electrode materials described in the present invention can improve the dispersion of powder by crushing the powder by airflow blowing, and can separate the magnetic substances from the powder by adsorption by electromagnetic adsorption. At the same time, by circulating airflow blowing and electromagnetic adsorption, the agglomeration phenomenon can be completely eliminated, the magnetic substances are exposed, and the effective adsorption rate of the magnetic substances is improved, thereby improving the accuracy of quantitative analysis and testing of magnetic substances.

[0018] Another object of the present invention is to provide a device for separating magnetic substances in silicon-based negative electrode materials, comprising:

[0019] A pulverizing chamber having a feeding port for feeding powder;

[0020] An air blowing device, comprising an air blowing portion connected to the pulverizing chamber, the air blowing portion being used to provide air flow to the pulverizing chamber to blow away the powder;

[0021] A separation device, comprising a spiral flow channel connected to the pulverizing chamber, and an electromagnetic adsorption portion arranged near the spiral flow channel, wherein the axis of the spiral flow channel is arranged along the height direction, and the electromagnetic adsorption portion is used to adsorb magnetic substances in the powder flowing in the spiral flow channel and trap the magnetic substances in the spiral flow channel;

[0022] The transfer device includes a transfer chamber connecting the spiral flow channel and the crushing chamber, and a transfer platform arranged in the transfer chamber. The transfer platform can receive the separated powder and transport the powder to the crushing chamber, and under the blowing of the blowing part, the separated powder can be transported to the spiral flow channel.

[0023] Furthermore, the electromagnetic adsorption portion includes a support seat, and an electromagnet disposed on the support seat; and / or the spiral flow channel encloses a columnar space, and the electromagnetic adsorption portion has an electromagnet located in the columnar space.

[0024] Furthermore, the transfer chamber is extended along the height direction and has an upper chamber and a lower chamber arranged vertically, and the transfer platform is slidably disposed between the upper chamber and the lower chamber; the blowing part is connected to the crushing chamber through the upper chamber, and / or the transfer device also includes a water supply part connected to the lower chamber, and the water supply part is used to supply water to the lower chamber and drive the transfer platform to move up and down.

[0025] Furthermore, the transfer platform is provided with a detection unit for detecting the weight of the powder; and / or the blowing part is connected to the grinding chamber through a purge pipeline, and a heating unit for heating the airflow is provided on the purge pipeline.

[0026] Furthermore, it also includes a cleaning device connected to the crushing chamber, the cleaning device is used to transport a cleaning agent into the crushing chamber to clean the crushing chamber and the spiral flow channel; and / or, it also includes a collecting device connected to the transfer chamber, the collecting device has a first storage part for storing the powder on the transfer platform, and a second storage part for storing the magnetic material.

[0027] The device for separating magnetic substances in silicon-based negative electrode materials described in the present invention can break up powder by means of airflow blowing through a blowing portion, and can extract the magnetic substances in the powder by means of electromagnetic adsorption through the coordinated arrangement of a spiral flow channel and an electromagnetic adsorption portion. At the same time, in combination with the coordinated use of a rotating chamber and a transfer platform, cyclic crushing and cyclic adsorption of the powder can be achieved to completely eliminate agglomeration, expose the magnetic substances, and improve the effective adsorption rate of the magnetic substances, thereby improving the accuracy of quantitative analysis and testing of the magnetic substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 Schematic diagram of a process for separating magnetic substances from silicon-based negative electrode materials according to an embodiment of the present invention;

[0030] Figure 2 It is a structural schematic diagram of a device for separating magnetic substances in silicon-based negative electrode materials according to an embodiment of the present invention;

[0031] Description of reference numerals:

[0032] 1. Feed hopper; 2. Crushing chamber; 3. Transfer chamber; 4. Cleaning pipeline; 5. Purge pipeline; 6. Stop valve; 7. Water drive pipeline; 8. Heating unit; 9. Pure water storage tank; 10. Base; 11. Central console; 12. Ethanol storage tank; 13. Electromagnet; 14. Transfer platform; 15. Spiral flow channel; 16. Collecting device; 17. Support seat; 18. Gate valve; 19. Transparent protective cover;

[0033] 301, upper chamber; 302, lower chamber. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0036] The present embodiment relates to a method for separating magnetic substances in silicon-based negative electrode materials, which can completely eliminate agglomeration, expose the magnetic substances, effectively adsorb and extract the magnetic substances, and thus improve the accuracy of quantitative analysis and testing of the magnetic substances.

[0037] In terms of overall design concept, as a preferred implementation method, Figure 1 As shown, the method for separating magnetic substances from silicon-based negative electrode materials in this embodiment mainly includes the following steps:

[0038] S1, obtaining powder to be separated.

[0039] S2, crushing the powder by air blowing.

[0040] S3, separate the magnetic substances in the powder by electromagnetic adsorption.

[0041] S4, obtaining the separated powder, and circulating S2 and S3 to separate and process the powder multiple times.

[0042] Based on the above overall introduction, as a preferred implementation form, the separation method of this embodiment also includes the following steps: S5, respectively collecting and storing the powder and magnetic substance after multiple separation treatments in S4 to obtain a powder collection system and a magnetic substance collection system.

[0043] In the specific implementation, in this embodiment, as a preferred implementation form, the following steps are further included between S4 and S5: S401, the magnetic material after multiple separation treatments in S4 is rinsed with a cleaning agent, and at the same time, the powder collection system includes solid powder and powder dispersed in the cleaning agent. In this way, the powder and the magnetic material can be effectively separated.

[0044] Furthermore, as a preferred implementation, the separation method of this embodiment further includes step S402 between S401 and S5: eliminating the electromagnetic adsorption operation on the magnetic substance, and infiltrating the magnetic substance with a cleaning agent to obtain a cleaning agent that disperses the magnetic substance to obtain a magnetic substance collection system.

[0045] At the same time, as a preferred embodiment, the cleaning agent of this embodiment includes at least one of ethanol and pure water, and in the specific implementation, the type of cleaning agent and the order of use can be selected according to the actual cleaning needs. For example, the adsorbed magnetic material can be rinsed with pure water first, then rinsed with ethanol, and finally rinsed with pure water to completely wash away the powder mixed in the magnetic material. Or in order to completely collect the magnetic material, ethanol can be used for immersion first, and then pure water can be used for rinsing to collect the magnetic material.

[0046] In addition, in S4 of this embodiment, as a preferred implementation, when the separated powder material reaches the cycle threshold, S2 and S3 are cycled. The cycle threshold here can be set and adjusted accordingly according to the powder material crushing requirements, for example, it can be a value between 30% and 50%, such as 30%, 40% or 50%, so as to obtain the best cycle crushing effect.

[0047] Secondly, also as a preferred implementation, the environmental humidity in the embodiments S1 to S4 is below 40%, for example, specifically 40%, 30% or 20%, to avoid powder agglomeration caused by excessive humidity and affect the powder crushing effect.

[0048] It is worth mentioning that the powder in this embodiment refers to electrode powder containing magnetic substances, such as powder composed of silicon-based negative electrode materials, and its average particle size can be between 0.5μm and 50μm. It should also be noted that silicon-based negative electrode materials are a general term for a large category including silicon oxide, silicon carbide, etc., that is, the raw materials of silicon-based negative electrodes are mainly composed of silicon materials and graphite.

[0049] Among them, silicon-based negative electrodes mainly include two categories: 1) single-element silicon negative electrode, whose theoretical specific capacity is as high as 4.200mAh / g, which is more than 10 times that of graphite negative electrode; 2) silicon oxide negative electrode, whose theoretical specific capacity is 2.600mAh / g, which is also much higher than graphite negative electrode.

[0050] Therefore, silicon-based negative electrodes have the advantages of high energy density, wide distribution of raw materials and suitable discharge platform. Silicon-based negative electrodes have obvious advantages, no hidden dangers of lithium precipitation, better safety than graphite negative electrode materials, and abundant reserves and low cost. Silicon-based negative electrodes can provide channels for lithium ion embedding and extraction from all directions, and have excellent fast charging performance. They are the most promising next-generation lithium battery negative electrode materials.

[0051] In the separation method of this embodiment, step S401 and step S402 can be circulated when necessary to purify and collect the magnetic substance. In this embodiment, the method of crushing the powder by circulating airflow blowing and electromagnetic adsorption can effectively solve the agglomeration and sedimentation phenomenon, so that the magnetic substance can be completely exposed and extracted, thereby solving the problem of deviation between the quantitative analysis test results of the magnetic substance and the true value, compared with the conventional dispersant composed of pure water, ethanol and NMP (N-methylpyrrolidone) in the prior art.

[0052] In addition, based on the airflow blowing method and electromagnetic adsorption method, it can also avoid the generation of a large amount of suspended waste liquid with high treatment costs during the test process, and solve the problem of high costs of consumables such as dispersants and cleaning agents.

[0053] The separation method of the present invention can improve the dispersion of powder by crushing powder with air flow blowing, and can adsorb magnetic substances from powder by combining with electromagnetic adsorption. At the same time, through circulating air flow blowing and electromagnetic adsorption, agglomeration can be completely eliminated to expose magnetic substances, thereby improving the effective adsorption rate of magnetic substances, and thus improving the accuracy of quantitative analysis and testing of magnetic substances.

[0054] In addition, the present invention also relates to a separation device for magnetic substances in silicon-based negative electrode materials, which can implement the above-mentioned separation method to achieve separation and purification of magnetic substances, thereby improving the accuracy of subsequent quantitative analysis and testing of magnetic substances.

[0055] In terms of overall structure, Figure 2 As shown, the separation device of this embodiment includes a crushing chamber 2, a blowing device, a separation device and a transfer device. The crushing chamber 2 has a feeding port for feeding powder. The blowing device includes a blowing part connected to the crushing chamber 2, and the blowing part is used to provide airflow to the crushing chamber 2 to blow away the powder.

[0056] The separation device includes a spiral flow channel 15 connected to the crushing chamber 2, and an electromagnetic adsorption portion arranged near the spiral flow channel 15. The axis of the spiral flow channel 15 is arranged along the height direction, and the electromagnetic adsorption portion is used to adsorb the magnetic substance in the powder flowing in the spiral flow channel 15 and retain the magnetic substance in the spiral flow channel 15.

[0057] The transfer device includes a transfer chamber 3 connecting the spiral flow channel 15 and the crushing chamber 2, and a transfer platform 14 arranged in the transfer chamber 3. The transfer platform 14 can receive the separated powder and transport the powder to the crushing chamber 2, and under the blowing of the blowing part, the separated powder can be transported to the spiral flow channel 15.

[0058] As a preferred exemplary structure, the electromagnetic adsorption part of this embodiment includes a support seat 17, and an electromagnet 13 disposed on the support seat 17. At the same time, in this embodiment, as a preferred implementation form, the spiral flow channel 15 encloses a columnar space, and the electromagnet 13 in the electromagnetic adsorption part is located in the columnar space.

[0059] In specific implementation, the electromagnet 13 can be preferably set to a cylindrical shape and arranged coaxially with the axis of the spiral flow channel 15 to facilitate determining a better adsorption effect, and the axis here refers to the spiral axis of the spiral flow channel 15. Of course, in addition to setting the electromagnet 13 to a cylindrical shape, the electromagnet 13 can also be set to other shapes such as a spiral shape that matches the spiral flow channel 15 to facilitate obtaining the best electromagnetic adsorption effect.

[0060] Meanwhile, as a preferred implementation form, in this embodiment, the transfer chamber 3 is extended in the height direction and has an upper chamber 301 and a lower chamber 302 arranged vertically, and the transfer platform 14 is slidably disposed between the upper chamber 301 and the lower chamber 302. The blowing part is connected to the crushing chamber 2 through the upper chamber 301, and the transfer device further includes a water supply part connected to the lower chamber 302, which is used to supply water to the lower chamber 302 and drive the transfer platform 14 to move up and down.

[0061] In this configuration, water can be supplied to the lower chamber 302 through the water supply part to drive the transfer platform 14 to receive the separated powder at the lower chamber 302, and transport the powder to the upper chamber 301, and the powder is purged by the blowing part in the upper chamber 301, and then transported to the crushing chamber for crushing again. In the specific structure, the water supply part here can be connected to the lower chamber 302 through the water drive pipeline 7.

[0062] In order to realize the cyclic crushing of powder, in this embodiment, as a preferred implementation form, a detection unit for detecting the weight of powder is provided on the transfer platform 14, so that when the above-mentioned circulation threshold is detected, the transfer platform 14 transports the powder between the lower chamber 302 and the upper chamber 301.

[0063] Furthermore, in order to ensure the accuracy of subsequent quantitative analysis tests of magnetic materials, the separation equipment of this embodiment needs to be dried before use. Based on this, as a preferred implementation form, the blowing part is connected to the crushing chamber 2 through a purge pipe 5, and a heating unit 8 for heating the airflow is provided on the purge pipe 5.

[0064] The heating unit 8 here and the above-mentioned detection unit can both adopt related equipment products commonly used by technical personnel in this field. For example, the heating unit 8 can adopt a heating wire, and the detection unit can adopt a weighing sensor or a pressure sensor.

[0065] In addition, as a preferred implementation form, the separation equipment of this embodiment also includes a cleaning device connected to the crushing chamber 2, and the cleaning device is used to transport a cleaning agent into the crushing chamber 2 to clean the crushing chamber 2 and the spiral flow channel 15.

[0066] In order to collect powder or magnetic material, as a preferred implementation form, the separation equipment of this embodiment also includes a collecting device 16 connected to the transfer chamber 3, and the collecting device 16 has a first storage part for storing powder on the transfer platform 14, and a second storage part for storing magnetic material.

[0067] It is worth mentioning that the specific structural form of the cleaning device in this embodiment can be designed according to actual cleaning needs. For example, it includes a pure water storage tank 9 and an ethanol storage tank 12, and a cleaning pipeline 4 is connected between the pure water storage tank 9 and the crushing chamber 2, and between the ethanol storage tank 12 and the crushing chamber 2.

[0068] In this embodiment, the first storage part may include a first collecting tank for collecting solid powder and a second collecting tank for collecting powder dispersed in the cleaning agent, and the second storage part includes a third collecting tank for collecting magnetic substances dispersed in the cleaning agent.

[0069] Moreover, the spiral flow channel 15 of this embodiment is preferably a transparent spiral tube, and the separation device is preferably configured to include a transparent protective cover 19 covering the spiral flow channel 15, so as to protect the separation device and the operator while facilitating the operator to observe the adsorption situation in the spiral flow channel 15.

[0070] Based on the overall installation and layout requirements of the separation equipment of this embodiment, a base 10 can also be provided to install and support related equipment such as the crushing chamber 2, the blowing device, the separation device and the transfer device. In order to achieve an integrated design, the water source of the water supply unit can directly use a pure water storage tank 9, and a central console 11 with a control unit is provided on the base 10. The control unit is connected to the blowing device, the separation device, the transfer device, the water supply unit and other devices that need to be controlled, so as to control the operation of the entire equipment.

[0071] At the same time, in order to facilitate the feeding of the powder to be separated, the pulverizing chamber 2 is connected to the feed hopper 1. A stop valve 6 is provided between the spiral flow channel 15 and the lower cavity, and a gate valve 18 is provided between the collecting device 16 and the lower cavity, so as to control the on-off between the spiral flow channel 15 and the lower cavity and between the collecting device 16 and the lower cavity.

[0072] As for the various structures not mentioned in the constituent devices of the separation equipment such as the crushing chamber 2, the blowing device, the separation device and the transfer device in this embodiment, they can all refer to the common related structural parts in the prior art and will not be described in detail here.

[0073] The separation device of the present invention can be provided with a blowing part to break up the powder by means of airflow blowing, and through the coordinated setting of the spiral flow channel 15 and the electromagnetic adsorption part, the magnetic substance in the powder can be extracted by means of electromagnetic adsorption. At the same time, combined with the coordinated use of the rotating chamber and the transfer platform 14, the cyclic crushing and cyclic adsorption of the powder can be realized to completely eliminate the agglomeration phenomenon, expose the magnetic substance, and improve the effective adsorption rate of the magnetic substance, thereby improving the accuracy of the quantitative analysis test of the magnetic substance.

[0074] In addition, in order to facilitate understanding of the implementation process of the method for separating magnetic substances in silicon-based negative electrode materials, the present invention also describes the separation method in detail in combination with the separation equipment. For example, before use, the overall air tightness of the equipment must be checked first, and the transfer chamber 3 and the spiral flow channel 15 must be demagnetized. The ambient humidity is controlled below 40% by a dehumidifier to prevent moisture carried in the air from wetting the powder, affecting the crushing of the original agglomerates and causing the fluidization of the powder. And when the present invention is used, the work content is cleaning process-drying process-circulation crushing process-cleaning process-collection process-drying process, and the specific details are as follows:

[0075] In the cleaning process, the stop valve 6 and the gate valve 18 are always open, the transfer platform 14 is at the bottom of the transfer chamber 3 (lower chamber 302), flush with the collection pipeline of the collection device 16, and the central control console 11 starts the cleaning device. First, 50ml of ethanol (provided by the ethanol storage tank 12) is output through the cleaning pipeline 4 to wet the impurities remaining in the equipment (the impurities include the powder remaining from the last use), and it is left to stand for 2 minutes so that the ethanol can fully wet the powder, and then 500ml of pure water (provided by the pure water storage tank 9) is output. Relying on the strong shear force of pure water in a turbulent state, the impurities attached to the crushing chamber 2 and the spiral flow channel 15 are cleaned, and finally 50ml of ethanol is output to rinse the pure water attached to the inner wall of the equipment, so that it is convenient to blow out the hot drying equipment through the blowing part and the heating wire, and the waste liquid generated by the cleaning is collected in the waste collection bottle. In addition, the cleaning condition of the equipment can be observed. If there are obvious solid impurities attached, the cleaning process is repeated several times under the control of the central control console 11 until the cleaning condition of the equipment meets the standard.

[0076] During the drying process, the gate valve 18 and the cleaning pipeline 4 are closed, and the stop valve 6 is maintained in an open state. The transfer platform 14 is at the bottom of the transfer chamber 3 (lower chamber 302) and is flush with the collection pipeline of the collection device 16. The central control console 11 opens the blowing part and the heating wire to heat the air and purge it into the equipment through the purge pipeline 5 for 15 minutes.

[0077] In the cyclic crushing process - cleaning process - collection process, the pre-weighed silicon-based negative electrode powder is added to the feed hopper 1, and 30% to 50% of the weighed silicon-based negative electrode powder is preset as the cycle threshold of the weighing sensor signal output, and the number of cycles of the circulation process, the number of cycles of the cleaning process and the number of cycles of the collection process are set on the central control console 11. At this time, the transfer platform 14 is at the bottom of the transfer chamber 3 (lower chamber 302), and the central control console 11 starts the circulation process, opens the stop valve 6, the electromagnet 13 and the blowing part, and the powder enters the spiral flow channel 15. The magnetic substance in the powder is trapped inside the spiral flow channel 15 under the action of the magnetic field of the electromagnet 13, and the remaining powder is accumulated on the transfer platform 14 until the cycle threshold of the weighing sensor signal output is reached;

[0078] Secondly, the central control panel 11 closes the stop valve 6 and opens the water supply part. The central control panel 11 outputs a fixed volume of pure water to the lower chamber 302, drives the transfer platform 14 to move to the upper chamber 301, and the powder enters the crushing chamber 2 under the blowing action of the blowing part, and the original agglomerates in the powder are depolymerized and dispersed under the shear force of the airflow, and the magnetic material is completely exposed and enters the spiral flow channel 15 again for magnetic separation. After that, the process is circulated to a preset number of cycles. When the cycle is completed, the central control panel 11 opens the gate valve 18, and the powder separated by magnetic separation enters the collection pipeline and is collected in the first collection tank;

[0079] Subsequently, the first collecting tank is replaced with the second collecting tank, the stop valve 6 and the gate valve 18 are both normally open, the transfer platform 14 is at the bottom of the transfer chamber 3, flush with the collection pipeline of the second collecting tank, and the central control console 11 starts the cleaning process (similar to the above cleaning process). The cleaning device first outputs 50ml of ethanol to wet the powder remaining in the equipment, and stands for 2 minutes so that the ethanol can fully wet the powder, and then outputs 500ml of pure water. Relying on the strong shear force of pure water in a turbulent state, the powder attached to the crushing chamber 2 and the spiral flow channel 15 is cleaned, and finally 50ml of ethanol is output to rinse the pure water attached to the inner wall of the equipment, so that it is convenient to blow out the hot drying equipment through the blowing part and the heating wire, and the cleaning waste liquid is collected in the second collecting tank. Similarly, the cyclic cleaning process presets the number of cycles, and the cleaning condition of the equipment can be observed. If there are obvious solid impurities attached, the cleaning process is repeated under the control of the central control console 11 until the cleaning condition of the equipment meets the standard;

[0080] When the cycle is finished, the second collection tank is replaced with the third collection tank, the electromagnet 13 is turned off, the stop valve 6 and the gate valve 18 are both normally open, the transfer platform 14 is at the bottom of the transfer chamber 3, flush with the collection pipeline, the central control console 11 opens the cleaning pipeline 4, first outputs 50ml of ethanol to wet the magnetic material in the spiral flow channel 15, and let it stand for 2 minutes so that the ethanol can fully wet the magnetic material, and then outputs 50ml of pure water. Relying on the strong shear force of pure water in a turbulent state, the magnetic material attached to the equipment is cleaned, and the magnetic material is collected in the third collection tank. Here, the collection process can also be cycled to a preset number of cycles to thoroughly collect the magnetic material and avoid any residue in the third collection tank.

[0081] In the final drying process, close the gate valve 18 and the cleaning pipeline 4, maintain the stop valve 6 in the open state, and the transfer platform 14 is at the bottom of the transfer chamber 3, flush with the collection pipeline. At this time, the central control console 11 opens the blowing part and the heating wire, heats the air and blows it into the equipment through the purge pipeline 5 for 15 minutes.

[0082] It should be noted that the relevant technical parameters in this embodiment can be set and adjusted according to the actual implementation requirements of the corresponding process. For example, the output of pure water can be set to 800 ml in addition to 500 ml, the output of ethanol can be set to 60 ml or 80 ml in addition to 50 ml, the ethanol infiltration time is between 2 and 10 minutes, and the purge time of heated air in the drying process is between 15 and 20 minutes.

[0083] As for the subsequent quantitative analysis test method of magnetic substances, common test methods in the field can be used. For example, a magnetic rod is placed in a magnetic substance collection system, fully in contact with the magnetic substance in the collection system for 15 minutes, and then the magnetic rod is taken out and transferred to a digestion tube, and digested with 50% aqua regia for 60 minutes. After the obtained solution is diluted, the magnetic substance content is quantitatively analyzed by ICP-OES (inductively coupled plasma optical emission spectrometer).

[0084] The separation method and separation equipment of this embodiment, when in use, can replace the traditional liquid phase dispersion method by a pneumatic crushing method and a method of cycling the pneumatic crushing method and the electromagnetic adsorption method, so as to achieve the purpose of effectively separating the magnetic material by magnetic separation, and only produce a small amount of cleaning waste liquid, which is green and environmentally friendly.

[0085] At the same time, only the materials need to be added manually and the collection tank in the collection device needs to be replaced, which greatly reduces the number of manual repetitive processes and effectively reduces labor costs. The cleaning process - drying process - cycle crushing process - cleaning process - collection process - drying process are integrated into one device as a whole, with high integration and conducive to the realization of equipment automation.

[0086] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for separating magnetic substances in silicon-based negative electrode materials, characterized in that: include: A grinding chamber having a feeding port for feeding powder; An air blowing device, comprising an air blowing portion connected to the pulverizing chamber, the air blowing portion being used to provide air flow to the pulverizing chamber to blow away the powder; A separation device, comprising a spiral flow channel connected to the pulverizing chamber, and an electromagnetic adsorption portion arranged near the spiral flow channel, wherein the axis of the spiral flow channel is arranged along the height direction, and the electromagnetic adsorption portion is used to adsorb magnetic substances in the powder flowing in the spiral flow channel and trap the magnetic substances in the spiral flow channel; The transfer device comprises a transfer chamber connecting the spiral flow channel and the pulverizing chamber, and a transfer platform arranged in the transfer chamber, wherein the transfer platform can receive the separated powder and transfer the powder to the pulverizing chamber, and can transfer the separated powder to the spiral flow channel under the blowing of the blowing part; The transfer chamber is extended in the height direction and has an upper chamber and a lower chamber arranged up and down, and the transfer platform is slidably arranged between the upper chamber and the lower chamber; The blowing part is connected to the crushing chamber through the upper chamber, and / or the transfer device further includes a water supply part connected to the lower chamber, the water supply part is used to supply water into the lower chamber and drive the transfer platform to move up and down; It also includes a cleaning device connected to the pulverizing chamber, and the cleaning device is used to transport a cleaning agent into the pulverizing chamber to clean the pulverizing chamber and the spiral flow channel.

2. The device for separating magnetic substances in silicon-based negative electrode materials according to claim 1, characterized in that: The electromagnetic adsorption part includes a support seat and an electromagnet disposed on the support seat; and / or the spiral flow channel encloses a columnar space, and the electromagnetic adsorption part has an electromagnet located in the columnar space.

3. The device for separating magnetic substances in silicon-based negative electrode materials according to claim 1, characterized in that: The transfer platform is provided with a detection unit for detecting the weight of the powder; and / or, The air blowing part is connected with the pulverizing chamber through a purge pipeline, and a heating unit for heating air flow is arranged on the purge pipeline.

4. The device for separating magnetic substances in silicon-based negative electrode materials according to any one of claims 1 to 3, characterized in that: It also includes a collecting device connected to the transfer chamber, wherein the collecting device has a first storage part for storing the powder on the transfer platform, and a second storage part for storing the magnetic substance.

5. A method for separating magnetic substances from silicon-based negative electrode materials, characterized in that: A separation device for magnetic substances in a silicon-based negative electrode material according to any one of claims 1 to 4, wherein the separation method comprises the following steps: S1, obtaining powder to be separated; S2, crushing the powder by blowing air; S3, separating the magnetic substance in the powder by electromagnetic adsorption; S4, obtaining the separated powder, and circulating S2 and S3 to separate and process the powder multiple times.

6. The method for separating magnetic substances in silicon-based negative electrode materials according to claim 5, characterized in that: The following steps are also included: S5, respectively collecting and storing the powder and the magnetic substance after multiple separation treatments in S4 to obtain a powder collection system and a magnetic substance collection system.

7. The method for separating magnetic substances in silicon-based negative electrode materials according to claim 6, characterized in that: The following steps are also included between S4 and S5: S401, washing the magnetic material after multiple separation treatments in S4 with a cleaning agent; The powder collecting system includes the solid powder and the powder dispersed in the cleaning agent.

8. The method for separating magnetic substances in silicon-based negative electrode materials according to claim 7, characterized in that: Between S401 and S5, step S402 is also included: eliminating the electromagnetic adsorption operation on the magnetic substance, and infiltrating the magnetic substance with the cleaning agent to obtain the cleaning agent that disperses the magnetic substance, so as to obtain the magnetic substance collection system; and / or, The cleaning agent includes at least one of ethanol and pure water.

9. The method for separating magnetic substances in silicon-based negative electrode materials according to any one of claims 5 to 8, characterized in that: In S4, when the separated powder obtained reaches a circulation threshold, S2 and S3 are circulated; and / or the ambient humidity in S1 to S4 is below 40%.

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