High-purity graphite powder continuous purification system and method

Abstract

The invention discloses a high-purity graphite powder continuous purification system and method.The high-purity graphite powder continuous purification system comprises a purification system, the purification system comprises a purification bin, a heater and a heat preservation felt are installed outside the purification bin, an air supply assembly is installed at the bottom of the purification bin, a porous graphite disc is installed in the purification bin, and a filter I is installed at the top of the purification bin; a backflushing air inlet valve I is mounted at the top of the purification bin; the feeding system comprises a feeding tank, a material supply assembly and an air inlet valve I; the discharging system comprises a discharging tank, a discharging assembly and an air inlet valve II; the vacuum system is mounted at the top of the purification bin; and the control system is used for controlling the operation of the whole device. According to the invention, continuous purification of graphite powder is realized, cooperative linkage of a feeding system, a purification system and a discharging system is realized, a stable operation environment is continuously maintained in cooperation with a vacuum system, frequent shutdown for switching processes is not needed, the operation intermittent time is greatly reduced, and the purification capacity is improved.

Description

Technical Field

[0001] This invention relates to the field of graphite purification and processing technology for new energy anode materials, and in particular to a continuous purification system and method for high-purity graphite powder. Background Technology

[0002] my country's vigorous development of the new energy battery industry is a strategic decision with far-reaching significance. Firstly, my country has a high dependence on oil; developing electric vehicles can significantly reduce oil consumption in the transportation sector, decrease dependence on foreign oil, and achieve energy self-sufficiency and control. Secondly, by taking the lead in new energy battery technology, China can strive to have a greater say in the formulation of future global technology standards and market rules, seizing the commanding heights of future economy and technology. In the new energy battery industry, natural flake graphite plays a crucial role in the field of anode materials due to its unique layered structure, high theoretical capacity, and abundant resource reserves. The purity requirement for graphite powder in new energy battery anodes is 99.95%, but the purity of graphite obtained from graphite ore through reagent flotation is only 94%-95%. To achieve the 99.95% purity requirement for anode materials, high-purity purification of natural graphite powder is necessary. Currently, common high-purity purification methods include the alkaline-acid method, hydrofluoric acid method, chlorination roasting method, high-temperature method, and physicochemical purification method.

[0003] Alkali-acid method: Graphite is mixed with sodium hydroxide and reacted at 650°C to produce a water-insoluble hydroxide compound and a partially water-soluble product. Some impurities are removed by washing with water. Then, the product after alkali fusion is mixed with a certain concentration of hydrochloric acid solution and reacted at 60-90°C to convert the impurities into soluble chlorides. After washing with water, the product is dried to obtain a high-purity graphite product.

[0004] Hydrofluoric acid process: This method utilizes hydrofluoric acid to react with impurities in the raw ore, producing water-soluble fluorides and fluorosilicic acids. The impurities are then removed by washing with water, yielding high-grade graphite. This process is highly efficient at removing impurities, produces high-grade products, has minimal impact on graphite product performance, and consumes little energy. However, hydrofluoric acid is highly toxic and corrosive, requiring a strict wastewater treatment system during production, resulting in significant environmental investment.

[0005] Chlorination roasting method: This method involves mixing graphite with a certain amount of reducing agent, roasting it at 1000℃ under a specific atmosphere, and introducing chlorine gas to react with it. This causes the valuable metals in the material to transform into chlorides and complexes in the gaseous or condensed phases with lower melting and boiling points, which then escape and separate from the remaining components, thus purifying the graphite. This method has low energy consumption, high purification efficiency, high recovery rate, and low cost. However, chlorine gas is toxic and severely corrosive to metal products; leaks can cause serious environmental pollution.

[0006] High-temperature purification method: This method utilizes the fact that the melting point of graphite (3850℃) is much higher than the boiling point of the impurities it contains. Graphite is heated to above 2700℃, causing the impurities in the graphite to vaporize and escape first, thus achieving the purpose of purification. This process can produce high-purity graphite products, but high-temperature purification equipment is expensive, consumes a lot of electricity, and limits the scale of production, resulting in low output.

[0007] Physicochemical purification method: The graphite product to be purified is placed in a vacuum furnace and heated. By increasing the vacuum level in the furnace, the impurities in the graphite product automatically volatilize when they reach their saturated vapor pressure. In addition, halogen gas is used to convert oxides with high melting and boiling points in the graphite impurities into halides with low melting and boiling points, thus achieving the purification effect. This method has a lower power consumption rate than the high-temperature purification method and has a certain cost advantage. However, since this method uses an intermittent vacuum furnace, heating and cooling are required when purifying graphite powder, which reduces the utilization rate of the equipment and is not as efficient as the alkaline-acid method.

[0008] Currently, the main purification method for natural graphite anode materials in industry is the alkaline-acid method. This method is technically mature, easy to operate, and has high production efficiency. However, the waste liquid generated is difficult to treat, and if the treatment does not meet the standards, it will face environmental pressure.

[0009] To address the aforementioned technical problems, this invention provides a continuous purification system and method for high-purity graphite powder. Summary of the Invention

[0010] The purpose of this invention is to provide a continuous purification system and method for high-purity graphite powder to solve the problems existing in the prior art.

[0011] To achieve the above objectives, the present invention provides the following solution: The present invention provides a continuous purification system for high-purity graphite powder, comprising: A purification system, comprising a purification chamber, a heater and insulation felt installed outside the purification chamber, an air supply component installed at the bottom of the purification chamber, a porous graphite disc installed inside the purification chamber, a filter I installed at the top of the purification chamber, and a backflushing air inlet valve I installed at the top of the purification chamber. The feeding system includes a feeding tank, a feeding assembly, and an air inlet valve I. The feeding assembly is used to feed material to the feeding tank, and the air inlet valve I is used to supply air to the feeding tank. A feeding pipe is installed on the feeding tank, and the feeding pipe is connected to the inlet of the purification chamber. A feeding air replenishment valve and the feeding valve I are installed on the feeding pipe. The discharge system includes a discharge tank, a discharge assembly, and an air inlet valve II. The discharge assembly is used to extract graphite powder from the discharge tank, and the air inlet valve II is used to supply air to the discharge tank. The discharge tank is equipped with a discharge pipe, which is connected to the purification chamber. The discharge pipe is equipped with a discharge air supply valve and a discharge valve I. A vacuum system is installed on top of the purification chamber and is connected to the feed tank and the discharge tank via vacuum pipeline I. A control system is used to control the operation of the overall device.

[0012] The high-purity graphite powder continuous purification system provided by the present invention includes, in which the gas supply component comprises: A funnel-shaped gas distribution plate, which is fixed to the bottom of the purification chamber; A process gas inlet pipe is fixed to the bottom of the funnel-shaped gas distribution plate, and a mass flow meter is installed on the process gas inlet pipe. Inlet valve III, wherein the inlet valve III is installed on the process gas inlet pipe; The other end of the process gas inlet pipe is a process gas inlet, and an argon inlet is provided on the side wall of the process gas inlet pipe. An argon inlet valve is installed on the argon inlet.

[0013] According to the high-purity graphite powder continuous purification system provided by the present invention, the purification chamber, the feed tank and the discharge tank are all equipped with a feed detector and a vacuum gauge, and the purification chamber is equipped with a pyrometer; the purification chamber, the feed tank and the discharge tank are respectively equipped with a feed observation window.

[0014] According to the high-purity graphite powder continuous purification system provided by the present invention, the feeding component includes a vacuum feeder, the output end of which is connected to the feed tank, and a feed valve II is installed on the output end of the vacuum feeder.

[0015] According to the high-purity graphite powder continuous purification system provided by the present invention, the discharge component includes a vacuum discharge machine, the input end of which is connected to the discharge tank, and a discharge valve II is installed at the input end of the vacuum discharge machine.

[0016] According to the high-purity graphite powder continuous purification system provided by the present invention, the vacuum system includes a vacuum pump, the pump port of the vacuum pump is connected to the top of the discharge tank through a vacuum pipeline II and the purification chamber, a gate valve I and a pressure regulating valve are installed on the vacuum pipeline II, and the output end of the vacuum pump is connected to the feed tank and the discharge tank through the vacuum pipeline I.

[0017] According to the high-purity graphite powder continuous purification system provided by the present invention, the vacuum pipeline I is equipped with a gate valve II, a filter II, and a backflush inlet valve II.

[0018] A continuous purification method for high-purity graphite powder includes the following steps: S1. The control system initiates self-checks of each system to check the connection and sealing of the purification system, feeding system, discharging system, and vacuum system. It confirms that the feeding valve I, discharging valve I, feeding air replenishment valve, discharging air replenishment valve, air inlet valve I, air inlet valve II, and backflushing air inlet valve I are in the closed state, the filter I is not blocked, the porous graphite disc is firmly installed, and the heater, insulation felt, air supply component, feeding component, and discharging component are operating normally. Then, the vacuum system is started. The vacuum degree parameter is set through the control system, and the corresponding valves on the vacuum pipeline I are opened to perform vacuum treatment on the feeding tank, discharging tank, and purification chamber respectively until the set vacuum degree is reached in each tank and purification chamber. The vacuum system is then maintained at a low speed to keep the vacuum environment stable. Subsequently, the heater of the purification system is started, and the control system controls the operation of the heater. At the same time, the insulation felt is used to keep the purification chamber warm, and the temperature in the purification chamber is gradually raised to the set purification temperature. During the heating process, the vacuum degree in the purification chamber is continuously maintained through the vacuum system to prevent air from entering and affecting the purification effect. S2, start the feeding component of the feeding system, add the graphite powder raw material to be purified into the feeding tank through the feeding component. After feeding is completed, close the corresponding feed port of the feeding component. Then open the air inlet valve I to introduce inert gas into the feeding tank and adjust the air inlet pressure to the set value. At the same time, open the feeding replenishment valve to replenish and stabilize the pressure of the feeding pipeline to ensure smooth feeding. After confirming that the temperature and vacuum degree in the purification chamber have reached the set values, open the feeding valve I through the control system. Under the combined action of inert gas pressure and vacuum suction, the graphite powder to be purified in the feeding tank enters the porous graphite disc in the purification chamber through the feeding pipeline. During the feeding process, the feeding amount is monitored in real time by the control system to ensure that the graphite powder loading on the porous graphite disc meets the set requirements. After feeding is completed, close the feeding valve I, the feeding replenishment valve, and the air inlet valve I in sequence. At the same time, the vacuum system is used to perform vacuum treatment again on the feeding pipeline and the feeding tank to prepare for the next feeding. S3. After feeding is completed, maintain the set temperature and vacuum in the purification chamber, start the gas supply component at the bottom of the purification chamber, and introduce process gas into the purification chamber. The process gas blows the graphite powder evenly through the pores of the porous graphite disc, and reacts chemically with the impurities in the graphite powder, turning the impurities in the graphite into gas. During the purification process, the impurity gas in the graphite powder rises to the top of the purification chamber and is discharged through filter I. Filter I can prevent graphite powder from being discharged outside the purification chamber. If filter I becomes clogged during the filtration process, the backflushing inlet valve I is opened through the control system to introduce backflushing gas into filter I to backflush and clean filter I. After cleaning, the backflushing inlet valve I is closed and filtration continues. Then, according to the set purification time, heating, heat preservation, vacuum maintenance and process gas intake operations are continuously performed to ensure that the impurities in the graphite powder are fully volatilized and reacted, and the graphite powder purification is completed.

[0019] S4. After purification, the discharge valve I, feed gas replenishment valve, and argon gas inlet valve are opened through the control system. The purified high-purity graphite powder enters the discharge tank from the purification chamber through the discharge pipe under the combined action of inert gas pressure and vacuum suction. During the discharge process, the discharge volume is monitored in real time by the control system to ensure smooth discharge. After the discharge is completed, the discharge valve I, feed gas replenishment valve, and argon gas inlet valve are closed in sequence, and the discharge component of the discharge system is started to extract the high-purity graphite powder in the discharge tank for collection and packaging. After the discharge is completed, the discharge component is closed, and the discharge tank is evacuated through the vacuum system to prepare for the next discharge.

[0020] S5: After the first discharge operation is completed and the feed tank has completed vacuum pretreatment, the feeding, purification, and discharge operations are repeated. The graphite powder is fed into the purification chamber again for purification and discharge, realizing continuous purification of graphite powder. During continuous purification, the control system monitors the operating parameters of each system in real time. If the parameters deviate, the operating status of each component is automatically adjusted in time to ensure that the purification process is stable and the purification effect meets the standards. At the same time, the filter I is backwashed and cleaned regularly, the sealing of each valve and pipeline is checked regularly, and the feeding component, discharge component, and heater are maintained regularly to avoid equipment failure affecting continuous operation.

[0021] S6. After the purification operation is completed, stop the heater operation through the control system. After the temperature in the purification chamber drops to room temperature, stop the operation of all equipment, including the vacuum system, gas supply components, feeding components, and discharging components. Then close all valves and clean the purification chamber, feeding tank, discharging tank, porous graphite disc, filter I, and all pipelines to remove residual graphite powder and impurities and ensure the equipment is clean. After cleaning, check the equipment status, make equipment maintenance records, and prepare for the next purification operation.

[0022] The present invention discloses the following technical effects: This invention enables continuous purification of graphite powder, with the feeding, purification, and discharging systems working in synergy. Combined with a vacuum system, it maintains a stable operating environment without the need for frequent shutdowns to switch processes, significantly reducing downtime and increasing purification capacity. At the same time, the gas replenishment and pressure stabilization design for feeding and discharging ensures smooth material transport, prevents graphite powder from clogging pipes, reduces the incidence of production failures, and is suitable for the needs of large-scale industrial production.

[0023] This invention offers high purification precision and stable results. The purification chamber is equipped with a heater and insulation felt, which can precisely control the temperature and maintain a constant temperature environment. The porous graphite disc allows inert gas to penetrate the graphite powder layer evenly. Combined with filter I to filter impurities and backflushing cleaning function, it effectively prevents graphite powder from entering the vacuum system and causing graphite powder waste. The vacuum environment avoids air interference and prevents graphite powder oxidation, ensuring consistent product quality.

[0024] This invention features a high degree of automation and convenient operation and maintenance. The control system coordinates the operation of all components, monitors key parameters such as temperature and vacuum in real time and adjusts them automatically, reducing manual intervention, operation difficulty and labor costs. The system structure is reasonably designed, and vulnerable parts such as valves and filters are easy to inspect and maintain. The equipment cleaning process is simple, which can effectively extend the service life of the equipment and reduce long-term production and maintenance costs. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of the high-purity graphite powder continuous purification system of the present invention.

[0027] The components include: 1. Purification chamber; 2. Heater; 3. Insulation felt; 4. Filter I; 5. Backflush inlet valve I; 6. Feed tank; 7. Inlet valve I; 8. Feed pipe; 9. Feed replenishment valve; 10. Feed valve I; 11. Discharge tank; 12. Inlet valve II; 13. Discharge pipe; 14. Discharge replenishment valve; 15. Discharge valve I; 16. Control system; 17. Funnel-shaped gas distribution plate; 18. Process gas inlet pipe; 19. Mass flow meter. 20. Inlet valve III; 21. Argon inlet; 22. Argon inlet valve; 23. Feed detector; 24. Vacuum gauge; 25. Pyrometer; 26. Feed observation window; 27. Vacuum feeder; 28. Feed valve II; 29. ​​Vacuum discharge machine; 30. Discharge valve II; 31. Vacuum pump; 32. Slide valve I; 33. Pressure regulating valve; 34. Slide valve II; 35. Filter II; 36. Backflush inlet valve II; 37. Porous graphite disc. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Reference Figure 1 This invention provides a continuous purification system for high-purity graphite powder, comprising: The purification system includes a purification chamber 1, a heater 2 and an insulation felt 3 installed outside the purification chamber 1, an air supply component installed at the bottom of the purification chamber 1, a porous graphite disc 37 installed inside the purification chamber 1, a filter I 4 installed at the top of the purification chamber 1, and a backflushing air inlet valve I 5 installed at the top of the purification chamber 1. The feeding system includes a feeding tank 6, a feeding assembly, and an air inlet valve I7. The feeding assembly is used to feed the feeding tank 6, and the air inlet valve I7 is used to supply air to the feeding tank 6. A feeding pipe 8 is installed on the feeding tank 6, and the feeding pipe is connected to the inlet of the purification chamber 1. A feeding air replenishment valve 9 and a feeding valve I10 are installed on the feeding pipe 8. The discharge system includes a discharge tank 11, a discharge assembly, and an air inlet valve II 12. The discharge assembly is used to extract graphite powder from the discharge tank 11, and the air inlet valve II 12 is used to supply air to the discharge tank 11. A discharge pipe 13 is installed on the discharge tank 11, and the discharge pipe 13 is connected to the purification chamber 1. A discharge air supply valve 14 and a discharge valve I 15 are installed on the discharge pipe 13. The vacuum system is installed on the top of the purification chamber 1 and is connected to the feed tank 6 and the discharge tank 11 through vacuum pipeline I. Control system 16 is used to control the operation of the overall device.

[0031] The solution has been further optimized, and the gas supply components include: Funnel-shaped gas distribution plate 17 is fixed at the bottom of purification chamber 1; Process gas inlet pipe 18 is fixed to the bottom of funnel-shaped gas distribution plate 17, and a mass flow meter 19 is installed on the process gas inlet pipe 18. Inlet valve III20 is installed on process gas inlet pipe 18; The other end of the process gas inlet pipe 18 is the process gas inlet. An argon gas inlet 21 is provided on the side wall of the process gas inlet pipe 18, and an argon gas inlet valve 22 is installed on the argon gas inlet 21.

[0032] The design was further optimized by installing a feed detector 23 and a vacuum gauge 24 on the purification chamber 1, the feed tank 6 and the discharge tank 11, and a pyrometer 25 on the purification chamber 1; and a feed observation window 26 on the purification chamber 1, the feed tank 6 and the discharge tank 11 respectively.

[0033] The scheme is further optimized. The feeding component includes a vacuum feeder 27. The output end of the vacuum feeder 27 is connected to the feed tank 6. A feed valve II 28 is installed on the output end of the vacuum feeder 27.

[0034] The design is further optimized so that the discharge assembly includes a vacuum discharge machine 29, the input end of which is connected to the discharge tank 11, and a discharge valve II 30 is installed at the input end of the vacuum discharge machine 29.

[0035] Further optimization of the scheme: the vacuum system includes a vacuum pump 31. The pump port of the vacuum pump 31 is connected to the top of the discharge tank 11 through a vacuum pipeline II and to the purification chamber 1. A slide gate valve I 32 and a pressure regulating valve 33 are installed on the vacuum pipeline II. The output end of the vacuum pump 31 is connected to the feed tank 6 and the discharge tank 11 through the vacuum pipeline I.

[0036] The scheme has been further optimized by installing a slide gate valve II34, a filter II35, and a backflush inlet valve II36 on vacuum line I.

[0037] A continuous purification method for high-purity graphite powder includes the following steps: S1, via control system 16, initiate self-checks of each system, checking the connection and sealing of the purification system, feeding system, discharging system, and vacuum system. Confirm that feeding valve I10, discharging valve I15, feeding air supply valve 9, discharging air supply valve 14, air supply valve I7, air supply valve II12, and backflushing air supply valve I5 are closed; filter I4 is unblocked; porous graphite disc 37 is securely installed; and heater 2, insulation felt 3, air supply assembly, feeding assembly, and discharging assembly are operating normally. Then, start the vacuum system, setting the vacuum parameters via control system 16. Open the corresponding valves on vacuum pipeline I to evacuate the feed tank 6, discharge tank 11 and purification chamber 1 respectively until the set vacuum degree is reached in each tank and purification chamber 1. Then maintain the vacuum system at low speed to keep the vacuum environment stable. Then start the heater 2 of the purification system. The control system 16 controls the operation of the heater 2. At the same time, use the heat insulation felt 3 to keep the purification chamber 1 warm and gradually raise the temperature in the purification chamber 1 to the set purification temperature. During the heating process, the vacuum degree in the purification chamber 1 is continuously maintained through the vacuum system to prevent air from entering and affecting the purification effect. S2, start the feeding component of the feeding system, and add the graphite powder raw material to be purified into the feeding tank 6 through the feeding component. After feeding is completed, close the corresponding feed port of the feeding component, then open the air inlet valve I7 to introduce inert gas into the feeding tank 6, and adjust the air inlet pressure to the set value. At the same time, open the feed replenishment valve 9 to replenish and stabilize the pressure of the feed pipeline 8 to ensure a smooth feeding process. After confirming that the temperature and vacuum degree in the purification chamber 1 have reached the set values, open the feed valve I10 through the control system 16 to feed the tank. Under the combined action of inert gas pressure and vacuum suction, the graphite powder to be purified in 6 enters the porous graphite box in the purification chamber 1 through the feed pipe 8. During the feeding process, the feed rate is monitored in real time by the control system 16 to ensure that the graphite powder loading on the porous graphite disc 37 meets the set requirements. After the feeding is completed, the feed valve I10, the feed gas replenishment valve 9, and the gas inlet valve I7 are closed in sequence. At the same time, the vacuum system is used to re-vacuum the feed pipe 8 and the feed tank 6 to prepare for the next feeding. S3. After feeding, maintain the set temperature and vacuum in the purification chamber 1, start the gas supply component at the bottom of the purification chamber 1, and introduce process gas into the purification chamber 1. The process gas blows the graphite powder evenly through the pores of the porous graphite disc 37, and reacts chemically with the impurities in the graphite powder, turning the impurities in the graphite into gas. During the purification process, the impurity gas in the graphite powder rises to the top of the purification chamber 1 and is discharged through filter I4. Filter I (4) can prevent the graphite powder from being discharged outside the purification chamber (the graphite powder will be adsorbed by filter I). If filter I4 becomes blocked during the filtration process, the backflushing inlet valve I5 is opened through the control system 16 to introduce backflushing gas into filter I4 to backflush and clean filter I4. After cleaning, the backflushing inlet valve I5 is closed and filtration continues. Then, according to the set purification time, heating, heat preservation, vacuum maintenance and process gas inlet operations are continuously carried out to ensure that the impurities in the graphite powder are fully volatilized and reacted, and the graphite powder purification is completed.

[0038] S4. After purification, the discharge valve I15, feed gas valve (9), and argon gas inlet valve (22) are opened through the control system 16. The purified high-purity graphite powder enters the discharge tank 11 from the purification chamber 1 through the discharge pipe 13 under the combined action of inert gas pressure and vacuum suction (the discharge chamber is vacuum). During the discharge process, the discharge volume is monitored in real time by the control system 16 to ensure smooth discharge. After the discharge is completed, the discharge valve I15, feed gas valve (9), and argon gas inlet valve (22) are closed in sequence. The discharge component of the discharge system is started to extract the high-purity graphite powder in the discharge tank 11 for collection and packaging. After the discharge is completed, the discharge component is closed and the discharge tank 11 is vacuumed through the vacuum system to prepare for the next discharge.

[0039] S5, after the first discharge operation is completed and the vacuum pretreatment of the feed tank 6 is completed, the feeding, purification and discharge operations are repeated to feed into the purification chamber 1 again for purification and discharge, so as to realize the continuous purification operation of graphite powder. During the continuous purification process, the control system 16 monitors the operating parameters of each system in real time. If the parameters deviate, the operating status of each component is automatically adjusted in time to ensure the stability of the purification process and the purification effect meets the standards. At the same time, the filter I4 is backwashed and cleaned regularly, the sealing of each valve and pipeline is checked regularly, and the feeding component, discharge component and heater 2 are maintained regularly to avoid equipment failure affecting continuous operation.

[0040] S6. After the purification operation is completed, the heater 2 is stopped by the control system 16. After the temperature in the purification chamber 1 drops to room temperature, the operation of all equipment, including the vacuum system, gas supply components, feeding components, and discharging components, is stopped. Then, all valves are closed, and the purification chamber 1, feeding tank 6, discharging tank 11, porous graphite disc 37, filter I4, and all pipelines are cleaned to remove residual graphite powder and impurities, ensuring that the equipment is clean. After cleaning, the equipment status is checked, and equipment maintenance records are made to prepare for the next purification operation.

[0041] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0042] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A continuous purification system for high-purity graphite powder, characterized in that, include: A purification system, comprising a purification chamber (1), a heater (2) and an insulation felt (3) installed outside the purification chamber (1), an air supply assembly installed at the bottom of the purification chamber (1), a porous graphite disc (37) installed inside the purification chamber (1), a filter I (4) installed at the top of the purification chamber (1), and a backflushing air inlet valve I (5) installed at the top of the purification chamber (1). The feeding system includes a feeding tank (6), a feeding assembly and an air inlet valve I (7). The feeding assembly is used to feed the feeding tank (6), and the air inlet valve I (7) is used to supply air to the feeding tank (6). The feeding tank (6) is equipped with a feeding pipe (8), which is connected to the inlet of the purification chamber (1). The feeding pipe (8) is equipped with a feeding air replenishment valve (9) and a feeding valve I (10). The discharge system includes a discharge tank (11), a discharge assembly and an air inlet valve II (12). The discharge assembly is used to extract graphite powder from the discharge tank (11). The air inlet valve II (12) is used to supply air to the discharge tank (11). The discharge tank (11) is equipped with a discharge pipe (13). The discharge pipe (13) is connected to the purification chamber (1). The discharge pipe (13) is equipped with a discharge air supply valve (14) and a discharge valve I (15). A vacuum system is installed on the top of the purification chamber (1), and the vacuum system is connected to the feed tank (6) and the discharge tank (11) respectively through vacuum pipeline I; The control system (16) is used to control the operation of the overall device.

2. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The gas supply assembly includes: A funnel-shaped gas distribution plate (17) is fixed at the bottom of the purification chamber (1); Process gas inlet pipe (18), the process gas inlet pipe (18) is fixed at the bottom of the funnel-shaped gas distribution plate (17), and a mass flow meter (19) is installed on the process gas inlet pipe (18). Inlet valve III (20), said inlet valve III (20) is installed on the process gas inlet pipe (18); The other end of the process gas inlet pipe (18) is the process gas inlet. An argon gas inlet (21) is provided on the side wall of the process gas inlet pipe (18), and an argon gas inlet valve (22) is installed on the argon gas inlet (21).

3. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The purification chamber (1), the feed tank (6) and the discharge tank (11) are each equipped with a feed detector (23) and a vacuum gauge (24), and the purification chamber (1) is equipped with a pyrometer (25); the purification chamber (1), the feed tank (6) and the discharge tank (11) are each equipped with a feed observation window (26).

4. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The feeding assembly includes a vacuum feeder (27), the output end of which is connected to the feed tank (6), and a feed valve II (28) is installed on the output end of the vacuum feeder (27).

5. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The discharge assembly includes a vacuum discharge machine (29), the input end of which is connected to the discharge tank (11), and a discharge valve II (30) is installed at the input end of the vacuum discharge machine (29).

6. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The vacuum system includes a vacuum pump (31). The pump port of the vacuum pump (31) is connected to the top of the discharge tank (11) through a vacuum pipeline II and to the purification chamber (1). A slide gate valve I (32) and a pressure regulating valve (33) are installed on the vacuum pipeline II. The output end of the vacuum pump (31) is connected to the feed tank (6) and the discharge tank (11) through the vacuum pipeline I.

7. The continuous purification system for high-purity graphite powder according to claim 1, characterized in that, The vacuum line I is equipped with a slide gate valve II (34), a filter II (35), and a backflush inlet valve II (36).

8. A method for continuous purification of high-purity graphite powder, based on the continuous purification system for high-purity graphite powder according to any one of claims 1-7, characterized in that, Includes the following steps: S1, start the self-test of each system through the control system (16), check the connection and sealing of the purification system, feeding system, discharging system and vacuum system, confirm that the feeding valve I (10), discharging valve I (15), feeding air replenishment valve (9), discharging air replenishment valve (14), air inlet valve I (7), air inlet valve II (12) and backflushing air inlet valve I (5) are in the closed state, the filter I (4) is not blocked, the porous graphite disc (37) is installed firmly, and the heater (2), insulation felt (3), air supply component, feeding component and discharging component are operating normally. Then start the vacuum system and set the vacuum degree parameter through the control system (16). Open the corresponding valve on vacuum pipeline I and vacuum the feed tank (6), discharge tank (11) and purification chamber (1) respectively until the set vacuum degree is reached in each tank and purification chamber (1). Then maintain the vacuum system running at low speed to keep the vacuum environment stable. Then start the heater (2) of the purification system and control system (16) to control the operation of the heater (2). At the same time, use the heat insulation felt (3) to keep the purification chamber (1) warm and gradually raise the temperature in the purification chamber (1) to the set purification temperature. During the heating process, the vacuum degree in the purification chamber (1) is continuously maintained through the vacuum system to avoid air entering and affecting the purification effect. S2, start the feeding component of the feeding system, add the graphite powder raw material to be purified into the feeding tank (6) through the feeding component, close the corresponding feed port of the feeding component after feeding is completed, then open the air inlet valve I (7) to introduce inert gas into the feeding tank (6), adjust the air inlet pressure to the set value, and at the same time open the feed replenishment valve (9) to replenish and stabilize the pressure of the feeding pipeline (8) to ensure smooth feeding process. After confirming that the temperature and vacuum degree in the purification chamber (1) have reached the set value, open the feed valve I (10) through the control system (16) to feed the graphite powder raw material to be purified into the feeding tank (6). Under the combined action of inert gas pressure and vacuum suction, the graphite powder to be purified enters the porous graphite disc (37) in the purification chamber (1) through the feed pipe (8). During the feeding process, the feed amount is monitored in real time by the control system (16) to ensure that the graphite powder loading on the porous graphite disc (37) meets the set requirements. After the feeding is completed, the feed valve I (10), the feed gas replenishment valve (9), and the gas inlet valve I (7) are closed in sequence. At the same time, the feed pipe (8) and the feed tank (6) are vacuumed again by the vacuum system to prepare for the next feeding. S3. After feeding, maintain the set temperature and vacuum in the purification chamber (1), start the gas supply component at the bottom of the purification chamber (1), and introduce process gas into the purification chamber (1). The process gas blows the graphite powder evenly through the pores of the porous graphite disc (37), reacts chemically with the impurities in the graphite powder, and turns the impurities in the graphite into gas. During the purification process, the impurity gas in the graphite powder rises to the top of the purification chamber (1) and is discharged through filter I (4). Filter I (4) can prevent the graphite powder from being discharged outside the purification chamber. If filter I (4) becomes blocked during the filtration process, the backflushing inlet valve I (5) is opened through the control system (16) to introduce backflushing gas into filter I (4) to backflush and clean the filter I (4). After cleaning, the backflushing inlet valve I (5) is closed and filtration continues. Then, according to the set purification time, heating, heat preservation, vacuum maintenance and process gas inlet operations are continuously carried out to ensure that the impurities in the graphite powder are fully volatilized and reacted, and the graphite powder purification is completed. S4. After purification, the discharge valve I (15), feed gas valve (9), and argon gas inlet valve (22) are opened through the control system (16). The purified high-purity graphite powder enters the discharge tank (11) from the purification chamber (1) through the discharge pipe (13) under the combined action of inert gas pressure and vacuum suction. During the discharge process, the discharge volume is monitored in real time through the control system (16) to ensure smooth discharge. After the discharge is completed, the discharge valve I (15), feed gas valve (9), and argon gas inlet valve (22) are closed in sequence. The discharge component of the discharge system is started to extract the high-purity graphite powder in the discharge tank (11) for collection and packaging. After the discharge is completed, the discharge component is closed and the discharge tank (11) is vacuumed through the vacuum system to prepare for the next discharge. S5. After the first discharge operation is completed and the feed tank (6) has completed vacuum pretreatment, the feeding, purification and discharge operations are repeated. Feed, purify and discharge into the purification chamber (1) again to achieve continuous purification of graphite powder. During the continuous purification process, the control system (16) monitors the operating parameters of each system in real time. If the parameters deviate, the operating status of each component is automatically adjusted in time to ensure that the purification process is stable and the purification effect meets the standards. At the same time, the filter I (4) is backflushed and cleaned regularly, the sealing of each valve and pipe is checked regularly, and the feeding component, discharge component and heater (2) are maintained regularly to avoid equipment failure affecting continuous operation. S6. After the purification operation is completed, the heater (2) is stopped by the control system (16). After the temperature in the purification chamber (1) drops to room temperature, the operation of all equipment, including the vacuum system, gas supply components, feeding components, and discharge components, is stopped. Then, all valves are closed, and the purification chamber (1), feeding tank (6), discharge tank (11), porous graphite disc (37), filter I (4), and all pipelines are cleaned to remove residual graphite powder and impurities and ensure that the equipment is clean. After cleaning, the equipment status is checked, and equipment maintenance records are made to prepare for the next purification operation.

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