A high temperature method for purifying graphite with a main reactor structure with branch pipes

Abstract

This invention discloses a main reactor structure with branch pipes for high-temperature graphite purification, relating to the fields of high-temperature metallurgy and graphite purification technology. Specifically, it is a main reactor structure with branch pipes for high-temperature graphite purification, comprising a high-temperature plasma source, a double-layer water-cooled jacketed chamber, connecting pipes with branch pipes, and a multi-layer mesh perforated structure at the branch pipe bends. The high-temperature plasma source provides the heat source. The upper and lower ends of the double-layer water-cooled jacketed chamber are respectively connected to the heat source and the discharge, and its chamber wall is provided with spiral cooling water channels. The connecting pipes with branch pipes are located in the middle, extending into the chamber to form bends, and multi-layer mesh perforated structures are set at the bends, with their openings parallel to the direction of the plasma flame. This structure, by optimizing the branch pipe layout and mesh structure, effectively improves the mixing efficiency of high-temperature gas and graphite raw materials, enhances the impurity removal effect, and utilizes a water-cooling system to control the reaction temperature, thereby improving the graphite purification quality and equipment operational stability.

Description

Technical Field

[0001] This invention relates to the field of high-temperature metallurgy and graphite purification technology, specifically to a main reactor structure with branch pipes for high-temperature graphite purification. Background Technology

[0002] Graphite, as an allotrope of carbon, has become an indispensable key material in modern industry due to its excellent high-temperature resistance (melting point exceeding 3600℃), good electrical and thermal conductivity, chemical stability, and self-lubricating properties. Especially in new energy (such as lithium-ion battery anode materials requiring purity ≥99.95%), semiconductors (crucibles for single-crystal silicon growth requiring purity ≥99.99%), and the nuclear industry (high-temperature gas-cooled reactor moderators requiring impurity content controlled below ppm), extremely high purity requirements are placed on graphite. However, natural graphite ore (such as flake graphite and amorphous graphite) or artificial graphite usually contains a large number of impurities (such as silicates, aluminosilicates, iron and manganese oxides, sulfides, etc.). These impurities not only reduce the electrical properties and chemical stability of graphite but may also cause structural failure or contaminate the reaction system in high-temperature applications. Therefore, they must be removed through purification processes.

[0003] Traditional graphite purification methods mainly include flotation, alkaline-acid method, high-temperature roasting method, and chlorination roasting method, but all of them have significant limitations: Flotation can only remove some mineral impurities with large density differences, such as sulfides and quartz, from graphite. It is almost ineffective against impurities with similar density to graphite, such as silicates and metal oxides. The purity of the final product can usually only reach 90%-95%, which cannot meet the needs of high-end applications. The alkaline-acid method involves reacting strong alkali (such as NaOH) with acidic impurities (such as silicates) in graphite to generate soluble salts, which are then removed by acid washing. However, this method is ineffective at removing alkaline impurities (such as alumina and iron oxide), and the residual alkali metal ions may introduce new impurities. In addition, the use of strong acids and alkalis can cause serious environmental pollution and equipment corrosion problems. High-temperature roasting methods (such as the Atcheson furnace process) involve mixing graphite with coke and then introducing chlorine or air at 2500-3000℃ to volatilize impurities. However, this method relies on fossil fuels for heating, resulting in extremely high energy consumption (up to 5000-8000 kWh per unit product). Furthermore, the temperature control precision is low (±200℃), which can easily lead to partial oxidation or structural damage of the graphite itself. The purity after purification is generally only 99.0%-99.5%. Chlorination roasting involves reacting chlorinating agents (such as Cl2 and HCl) with impurities to generate volatile chlorides. However, the chlorination process may produce highly toxic gases (such as PCl5 and AsCl3), posing a significant threat to operator safety and the environment. Furthermore, the equipment requires extremely high corrosion resistance, limiting its industrial application.

[0004] In recent years, high-temperature plasma technology has gained popularity due to its high energy density (up to 10^6 kilometres per second). 6 -10 7 With its advantages of high heat capacity (W / m³), strong temperature controllability (precise adjustment from 1000-10000℃), and excellent reaction selectivity, graphite has gradually become a research hotspot for high-purity graphite purification. The principle involves using a high-frequency power supply to excite a working gas (such as argon or nitrogen) to generate a high-temperature plasma flame (temperatures can reach 8000-12000℃), heating the graphite raw material to a molten state. Simultaneously, impurities such as silicates and metal oxides are decomposed into gaseous compounds (such as SiO, FeO, Al₂O, etc.), which are ultimately carried out of the reactor by the gas flow. Graphite, due to the strong covalent bonds between carbon atoms (bond energy approximately 348 kJ / mol), remains solid at high temperatures, thus achieving the separation of impurities from graphite.

[0005] However, the core reactor of existing high-temperature plasma purification devices still faces many technical bottlenecks: Matching issues between heat source and reaction chamber: Traditional reactors often use a single plasma torch for direct heating, but the flame direction does not match the material distribution, resulting in local overheating (graphite melting and agglomeration) or local underheating (impurity residue), leading to low purification efficiency and poor product consistency. Low efficiency in separating airflow from impurities: The gaseous substances containing impurities generated in the reaction need to be quickly discharged and separated from solid graphite. However, the airflow channel design of the existing device is simple (such as straight pipe connection), which easily leads to the mixing of high-temperature airflow with unreacted particles, causing the cyclone separator to be overloaded or secondary entrainment, ultimately affecting the purity. Insufficient cooling and structural stability: The plasma flame temperature is extremely high (>8000℃), and the inner wall of the reactor needs to withstand extreme thermal shock (instantaneous temperature difference can reach more than 2000℃). If the cooling system is not designed properly (such as uneven distribution of cooling water channels), it can easily lead to local overheating deformation or even cracking of the chamber, which seriously affects the life and safety of the equipment. Discharge and continuous production are difficult: Solid residues after the reaction (such as unreacted impurity molten material and a small amount of graphite fragments) need to be discharged in time. However, the bottom of existing reactors is mostly flat, and the discharge port is easily blocked by the molten material. In addition, there is a lack of efficient connection structure with the downstream cyclone separator, making it difficult to achieve continuous purification production. Summary of the Invention

[0006] The purpose of this invention is to provide a main reactor structure with branch pipes for high-temperature graphite purification. By optimizing the connection method between the high-temperature plasma source and the double-layer water-cooled jacket, designing the connecting pipeline with branch pipes and the multi-layer mesh hollow elbow structure, and combining precise airflow guidance and cooling control, the invention effectively solves the technical pain points of traditional reactors, such as low heat source utilization, poor airflow separation efficiency, insufficient cooling stability, and difficulty in material discharge. This provides key equipment support for the industrial purification of high-purity graphite.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a main reactor structure with branch pipes for high-temperature graphite purification. The main reactor includes a heat source device for generating high-temperature plasma, located at the top of the reactor and connected to a reaction chamber with a double-layer structure and an internal cooling water circulation channel. The lower part of the reaction chamber is a double-layer inverted cone shape, with a connecting pipe with branch pipes inside. The connecting pipe is located in the middle of the reaction chamber and is used to separate and discharge the gas and solid particles generated during the reaction. At the same time, a multi-layer mesh elbow component with a hollow structure is provided at the branch part of the connecting pipe entering the reaction chamber. The central axis of the elbow component coincides with the central axis of the entire reactor, and the opening direction of its branch pipe is consistent with the direction of the high-temperature fluid jet generated by the heat source device.

[0008] Furthermore, the heat source device for generating high-temperature plasma is fixed to the upper part of the reaction chamber through a sealed connection structure. This sealed connection structure can effectively prevent high-temperature gas from leaking outward during the reaction process, ensuring the safety and stability of the reaction environment.

[0009] Furthermore, the reaction chamber with a double-layer structure and an internal cooling water circulation channel has a double-layer inverted cone design at the bottom, and an outlet is provided at the bottom of the inverted cone structure for discharging the purified product after the reaction is completed.

[0010] Furthermore, the cooling water circulation channels inside the double-layered walls of the reaction chamber are arranged in a spiral shape. This structural design can effectively improve the cooling effect and make the temperature distribution inside the reaction chamber more uniform, thereby improving the stability of the reaction process.

[0011] Furthermore, the main body of the connecting pipeline with branch pipes is firmly fixed to the outer wall of the middle part of the reaction chamber by welding to ensure the stability of the entire connecting structure and prevent loosening or deformation under high temperature and high pressure.

[0012] Furthermore, the connecting pipe with branch pipes has a main pipe section with a larger internal diameter than the branch pipe section. This design effectively balances the airflow between the main reactor and the subsequent separation device, ensuring smooth gas flow and separation effect.

[0013] Furthermore, the multi-layered mesh-like perforated structure set at the bend of the branch pipe is made of an alloy material that can withstand high temperatures. The structure has multiple uniformly arranged through holes to facilitate the separation and guidance of gas and solid particles.

[0014] Furthermore, the mesh components in the multi-layer mesh hollow structure are spaced appropriately apart. This spacing design can effectively control the airflow distribution and prevent blockage caused by particle accumulation during the reaction process.

[0015] Furthermore, the bending angle formed by the bend of the branch pipe is ninety degrees, so that the opening direction of the branch pipe is aligned with the direction of the high-temperature fluid jet generated by the heat source device, thereby improving the reaction efficiency and separation effect.

[0016] Furthermore, the reaction chamber with a double-layer structure and an internal cooling water circulation channel has an additional layer of insulation material on the outer side of its chamber wall. This insulation layer can effectively reduce heat loss during the reaction process, maintain the temperature inside the reactor in a stable state, and thus improve the efficiency and stability of the entire reaction process.

[0017] This invention provides a main reactor structure with branch pipes for high-temperature graphite purification, which has the following advantages: 1. The main reactor structure achieves continuous and stable heating under high-temperature conditions through a specially designed heat source supply device tightly integrated with the reaction chamber. The heat source device generates sufficiently high temperatures that directly act on the reactants, ensuring that the extreme temperature conditions required during graphite purification are precisely maintained. Simultaneously, the special construction of the reaction chamber concentrates and evenly distributes the high-temperature zone, avoiding localized overheating or underheating, thereby significantly improving reaction efficiency. This design not only optimizes energy utilization and reduces unnecessary heat loss but also ensures the continuity and controllability of the purification process, laying the foundation for large-scale industrial production.

[0018] The reaction chamber employs a double-layer water-cooled jacket design with spiral cooling water channels inside the chamber walls. This innovative structure significantly improves cooling efficiency. The cooling water evenly covers the entire chamber wall, promptly removing the large amount of heat generated during the reaction and effectively preventing equipment deformation or damage due to high temperatures. The spirally distributed cooling channels further enhance heat exchange capacity, ensuring uniform temperature distribution and avoiding the risk of localized overheating. Furthermore, the stable cooling system extends the equipment's lifespan, reduces maintenance frequency and costs, while ensuring operator safety and lowering the probability of production interruptions due to equipment failure.

[0019] Through the ingenious design of a multi-layered mesh-like perforated structure in the branch pipe bends, the main reactor achieves precise control over the high-temperature gas flow and reaction products. The branch pipes extend into the reaction chamber and form bends at specific angles, with their openings aligned with the heat source injection direction, ensuring smooth gas flow into the subsequent separation unit. The multi-layered mesh-like perforated structure not only evenly disperses the gas flow but also effectively filters large particulate impurities, reducing the burden on downstream separation equipment. This design significantly improves the separation efficiency of the gas flow and solid residues, allowing for rapid extraction of pure products while reducing the risk of blockage and ensuring smooth operation of the entire purification process.

[0020] The heat source unit is tightly connected to the reaction chamber via a sealed connection structure (such as a flange), ensuring that the high-temperature gas is completely contained within the reaction area and avoiding the risk of leakage. This design not only protects the health of operators but also prevents the high-temperature gas from damaging the surrounding environment. Simultaneously, the double-layered structure and robust materials of the reaction chamber can withstand extreme pressure and temperature changes, further enhancing the overall safety of the equipment. This combination of sealing and structural strength enables the reactor to operate stably in harsh industrial environments, reducing the probability of accidents and meeting the high standards of modern safe production.

[0021] A dedicated discharge port at the bottom of the reaction chamber facilitates rapid cleaning of solid residues after the reaction, reducing downtime. Meanwhile, the structural design of the branch pipes and connecting pipelines prioritizes ease of operation. For example, the difference in inner diameter between the main pipe and branch pipes optimizes airflow balance, while the detachable design of the multi-layered mesh perforated structure facilitates regular maintenance and replacement. These detailed design features significantly reduce the operational complexity of the equipment, enabling staff to easily perform daily inspections, cleaning, and maintenance. The overall human-centered design not only improves production efficiency but also reduces labor costs, providing significant convenience for industrial applications. Attached Figure Description

[0022] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the main reactor structure of the present invention; Figure 2 This is a vector diagram showing the temperature distribution and velocity under different branch pipe configurations within the main reactor of this invention. Figure 3 The diagram shows the streamlines of the main reactor of this invention under different branch pipe configurations. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses consistent with some aspects of this disclosure as detailed in the appended claims.

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Example 1 This embodiment focuses on the practical application scenario of a main reactor structure with branch pipes for high-temperature graphite purification, emphasizing the collaborative operation process of the high-temperature plasma source and the double-layer water-cooled sandwich chamber.

[0027] During the preparation phase, the graphite raw material to be purified must first be introduced through the top opening of the double-layered water-cooled jacketed chamber 2. Then, the high-temperature plasma source 1 is sealed to the upper end of the double-layered water-cooled jacketed chamber 2 via a flange structure to ensure that high-temperature gas does not leak. After the connection is completed and confirmed to be correct, the high-temperature plasma source 1 is activated. This plasma source generates a high-temperature flame, with temperatures reaching several thousand degrees Celsius. Immediately afterwards, the graphite raw material is introduced along with the carrier gas through the inlet pipe of the high-temperature plasma source 1. The high-temperature flame directly acts on the graphite raw material, causing impurities inside the graphite, such as silicates and metal oxides, to volatilize or decompose under high-temperature conditions.

[0028] The double-layered water-cooled sandwich chamber 2 has spirally distributed cooling water channels inside its walls, through which cooling water continuously circulates throughout the reaction process. This design effectively absorbs heat generated by the high temperatures on the inner walls of the chamber, thus protecting the structural stability. Furthermore, it prevents external overheating, reducing safety risks.

[0029] The main body of the connecting pipe 3 with branch pipes is welded to the outer wall of the middle section of the double-layer water-cooled jacket 2. The inner diameter of the main pipe is larger than that of the branch pipe; this design ensures a pressure balance between the high-temperature gas flow in the main reactor and the cyclone separator. When the plasma flame acts on the graphite, the resulting gaseous impurities (such as volatile compounds) and unreacted fine particles rise with the gas flow. Part of this gas flow enters the cyclone separator through the branch pipe of the connecting pipe 3. The bends in the branch pipe are designed at 90 degrees, and their axes are aligned with the axis of the main reactor, with the opening direction parallel to the flame direction of the high-temperature plasma source 1. This design allows the gas flow to be directly guided to the branch pipe along the flame jet path, thereby reducing turbulence interference.

[0030] The branch pipe elbow's multi-layered mesh perforated structure 4 is made of high-temperature resistant alloy material. Uniformly spaced through holes are arranged between its multi-layered mesh structure. These through holes not only filter large particulate impurities but also effectively control the uniformity of airflow distribution, preventing pressure imbalance within the reactor caused by localized blockages.

[0031] After the reaction is complete, the double-layered inverted conical discharge port at the bottom of the double-layered water-cooled jacket 2 opens, allowing the remaining pure graphite solids (with impurities having volatilized or deposited) to be discharged under gravity. Throughout the process, the insulation layer on the outside of the chamber reduces heat loss and maintains the stability of the high-temperature environment inside the reactor; simultaneously, the spiral distribution of the cooling water channels ensures temperature uniformity and prevents damage to the equipment due to localized overheating.

[0032] Example 2 This embodiment focuses on the practical verification of the cooling system design and impurity removal mechanism of the double-layer water-cooled sandwich chamber 2. The cooling water channels within the walls of the double-layer water-cooled sandwich chamber 2 are arranged in a spiral pattern. Cooling water is injected from the inlet at the top of the chamber and flows downwards along the spiral path to the outlet at the bottom, forming a continuous circulation. This design ensures full contact between the cooling water and the chamber walls, not only quickly removing the heat transferred from the high-temperature plasma source 1 to the chamber (the measured outer wall temperature of the chamber is consistently below 80°C), but also preventing material deformation caused by localized high temperatures through uniform temperature distribution. When the high-temperature plasma source 1 is operating, the flames generated at thousands of degrees Celsius directly act on the graphite raw materials inside the chamber. Without effective cooling measures, the chamber may crack due to thermal stress concentration. The spiral cooling channels in this design rapidly dissipate heat from the highest temperature area (the top of the chamber near the plasma source), ensuring the long-term reliability of the chamber structure.

[0033] The discharge port at the bottom of the double-layered inverted conical structure is the only outlet for the solid residue after the reaction. During the purification process, impurities in the graphite raw material (such as metal oxides like iron and aluminum) are converted into gaseous or microparticles at high temperatures. These particles are intercepted by the multi-layered mesh structure 4 of the branch pipe bend or enter the cyclone separator with the main airflow. The pure graphite solid, due to its high melting point and low volatility, eventually settles in the conical area at the bottom of the chamber. Operators can control the valve at the discharge port to discharge the finished graphite product at set times after the reaction. It is worth noting that the design of the discharge port matches the inverted conical structure of the double-layered water-cooled jacketed chamber—the conical inner wall allows solid particles to slide naturally to the central discharge port, avoiding material accumulation; at the same time, the insulation layer of the chamber wall reduces heat loss during the discharge process and prevents low-temperature gas from entering and causing the residual graphite to re-adsorb impurities.

[0034] This embodiment verifies the effectiveness of the cooling system through measured data: during continuous 8 hours of high-temperature operation, the temperature difference between the inlet and outlet of the cooling water in the chamber remained stable within the range of 15-20℃, and the highest temperature of the outer wall of the chamber was only about 10℃ higher than the ambient temperature. No structural deformation or weld cracking caused by thermal stress was observed. The impurity discharge process was smooth, and there was no blockage at the discharge port, demonstrating the dual advantages of the double-layer water-cooled sandwich chamber 2 in high-temperature reaction and material management.

[0035] Example 3 This embodiment describes the airflow control function of the connecting pipe 3 with branch pipes and the multi-layer mesh hollow structure 4 of the branch pipe elbows, focusing on its role in balancing the air pressure between the main reactor and the cyclone separator and optimizing impurity separation efficiency. The main body of the connecting pipe 3 with branch pipes is welded and fixed to the outer wall of the middle part of the double-layer water-cooled jacket 2. The inner diameter of the main pipe is larger than that of the branch pipe (e.g., the inner diameter of the main pipe is 50 mm, and the inner diameter of the branch pipe is 20 mm). This differentiated design ensures the air pressure balance between the mainstream path of the high-temperature airflow in the main reactor (through the main pipe) and the impurity airflow (containing volatile substances and fine particles) guided by the branch pipe. If the inner diameter of the branch pipe is too large, it may lead to insufficient air pressure in the main reactor, affecting the stability of the plasma flame; if the inner diameter of the branch pipe is too small, the impurity airflow is prone to backflow into the chamber due to excessive resistance. The proportions of this design have been optimized through fluid simulation to maintain the air pressure in the main reactor at a slightly negative pressure state of -50 to -100 Pa (relative to the outside), which ensures both the concentrated jetting of the plasma flame and avoids the leakage of harmful gases.

[0036] The bends in the branch pipe section are 90 degrees, and their opening direction is strictly parallel to the flame direction of the high-temperature plasma source 1. This allows the impurity gas flow rising from the middle of the chamber (which naturally diffuses towards the periphery of the flame due to the thermal buoyancy of the flame) to directly enter the branch pipe along the bend axis without the need for an additional power unit. The multi-layered mesh-like perforated structure 4 of the branch pipe bend is made of a high-temperature resistant alloy (such as Inconel 600). Its multi-layered mesh structure contains 5-8 layers of evenly distributed through holes (the diameter of a single through hole is 1-2 mm, and the spacing between layers is 5 mm). This structure can intercept coarse particles larger than 2 mm in diameter (such as incompletely reacted graphite fragments) while allowing gaseous impurities and small particles (such as metal vapor) to pass through. The spacing design between the multi-layered structure (leaving a 3-5 mm gap between layers) further prevents the through holes from becoming blocked due to carbon buildup or metal deposition. When a small amount of impurities adheres to the surface of the mesh layer, the subsequent airflow can bypass the obstacle through the through holes of the adjacent layer, maintaining overall air permeability.

[0037] In actual operation, the flow rate of the impurity gas can be controlled by adjusting the power and feed rate of the high-temperature plasma source 1. When the feed rate is relatively fast, the multi-layer mesh design of the branch pipe elbow multi-layer mesh hollow structure 4 can dynamically adapt to changes in airflow, ensuring that the impurity separation efficiency is not less than 90% (the solid particle content in the gas flow discharged into the cyclone separator is less than 0.1 g / m³), while the plasma flame intensity in the main reactor remains stable (the fluctuation range of flame length and diameter is less than 5%). This embodiment achieves synergistic optimization of airflow control, impurity interception, and reaction stability through structural innovation and material selection.

[0038] Example 4 This embodiment demonstrates the linkage mechanism and actual effect of each component in the high-temperature purification of graphite, combined with a specific operation process. First, the operator puts the graphite raw material to be purified (containing about 15wt% impurities) into the feed port at the top of the double-layer water-cooled jacketed chamber 2. Then, the high-temperature plasma source 1 is sealed to the upper end of the chamber through a flange structure (the sealing gasket is made of high-temperature resistant graphite material to ensure no gas leakage). Before starting, the cooling water system of the double-layer water-cooled jacketed chamber 2 is checked - the inlet pressure is maintained at 0.3-0.5MPa, and the water temperature is controlled at 25-30℃ to ensure that the spiral distribution of the cooling water channel can evenly cover the inner side of the chamber wall. Next, the high-temperature plasma source (1) is turned on. The high-temperature flame (temperature about 8000-10000K) generated by it directly acts on the surface of the graphite raw material, causing the silicate impurities in it to decompose into gaseous silicon dioxide, and the metal oxides (such as Fe2O3, Al2O3) to vaporize into metal vapor.

[0039] As the reaction proceeds, gaseous impurities and fine particles rise to the center of the chamber due to the thermal buoyancy of the flame. Some of them enter the multi-layered mesh structure 4 of the branch pipe bend through the branch pipe section of the connecting pipe 3 with branch pipes. The axis of this structure is consistent with the axis of the main reactor, and the opening direction is parallel to the flame direction, allowing the airflow to enter the branch pipe smoothly without turbulence caused by abrupt changes in direction. The multi-layered mesh structure 4 of the branch pipe bend intercepts most of the coarse particles (such as unreacted graphite powder), while gaseous impurities and small particles enter the branch pipe through the through holes and eventually flow to the cyclone separator for further separation. At the same time, the cooling water in the double-layered water-cooled jacket chamber 2 is continuously circulated, and the temperature on the outside of the chamber wall is always below 60°C. The insulation layer (such as ceramic fiber felt) controls the internal heat loss rate to within 10%, maintaining the stability of the high-temperature environment required for the reaction.

[0040] After the reaction is complete, the high-temperature plasma source 1 is shut off. Once the chamber temperature drops to a safe range (below 100°C), the discharge port at the bottom of the double-layered inverted conical structure is opened, and the pure graphite solid (with impurity content reduced to below 0.5 wt%) is discharged by gravity. Collection components (such as the dust collection bag downstream of the cyclone separator) can recover useful components from the gaseous impurities (such as high-purity metal powder after condensation of metal vapor). Throughout the operation, all components (high-temperature plasma source, double-layered water-cooled jacketed chamber, branch pipe structure) work collaboratively, achieving not only efficient graphite purification but also ensuring operational safety through the cooling system and sealing design, thus verifying the practicality and reliability of this structure.

[0041] Example 5 This embodiment details the advantages of the structural innovations of the double-layer water-cooled jacketed chamber 2 (especially the double-layer inverted conical bottom and insulation layer design) in actual production. The double-layer inverted conical structure is one of the key designs of this reactor: its upper part smoothly transitions to the cylindrical chamber, while the lower part gradually tapers towards the discharge port. This shape utilizes gravity to allow the pure graphite solids deposited after the reaction to naturally slide down to the central discharge port. Compared to traditional flat-bottomed chambers, the inverted conical structure eliminates dead zones for material accumulation, avoiding secondary contamination caused by residual impurities. The discharge port is controlled by a stainless steel ball valve, which can maintain a complete seal during the reaction (preventing high-temperature gas leakage) and can also be quickly opened during discharge (discharge time not exceeding 2 minutes), improving production efficiency.

[0042] The insulation layer on the outer side of the chamber (50-100mm thick, made of high-alumina refractory fiber) is another key design element for maintaining stable internal reactor temperature. During continuous operation of the high-temperature plasma source 1, the internal temperature of the chamber needs to be maintained at 3000-5000℃ (depending on the graphite purification process requirements). The insulation layer, with its low thermal conductivity (≤0.1W / (m·K)) and high temperature resistance (long-term operating temperature ≥1200℃), reduces heat radiation loss from the chamber surface by more than 70%. Actual measurement data shows that at an ambient temperature of 25℃, the outer wall temperature is only 40-50℃ (compared to over 300℃ without the insulation layer). This not only improves the safety of the operating environment (avoiding the risk of burns) but also reduces the load on the cooling water system—due to reduced external heat dissipation, the required cooling water flow rate is reduced by approximately 20%, thereby lowering energy consumption.

[0043] Furthermore, the cooling water channels within the double-layer water-cooled sandwich chamber 2 employ a double-layer structure (forming an annular channel between the inner and outer chamber walls), further enhancing cooling uniformity. Cooling water is injected from the upper part of the outer channel, flows through the annular space, and enters the lower part of the inner channel, forming a composite cooling mode of "outer layer pre-cooling - inner layer precise temperature control." This design ensures that the temperature gradient (the difference between the highest and lowest temperature points) on the inner wall of the chamber is less than 50°C, avoiding material fatigue cracks caused by localized overheating. This embodiment, through the synergistic effect of the inverted conical discharge structure, insulation layer, and composite cooling channels, achieves comprehensive optimization of high-temperature reaction, material management, energy consumption control, and operational safety, providing a reliable technical solution for industrial-grade graphite purification.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A main reactor structure with branch pipes for high-temperature graphite purification, characterized in that, The main reactor includes: a high-temperature plasma source (1) to provide a heat source for graphite purification; a double-layer water-cooled jacketed chamber (2) whose upper end is connected to the high-temperature plasma source (1) and whose lower end is a double-layer inverted conical structure, and cooling water channels are provided in the chamber walls of the double-layer water-cooled jacketed chamber (2); a connecting pipe (3) with branch pipes, which is located in the middle of the double-layer water-cooled jacketed chamber (2) to connect the main reactor with the cyclone separator; and a multi-layer mesh hollow structure (4) of branch pipe bends located inside the double-layer water-cooled jacketed chamber (2); wherein, the branch pipe portion of the connecting pipe (3) with branch pipes extends into the double-layer water-cooled jacketed chamber (2) and forms a bend, the multi-layer mesh hollow structure (4) of the branch pipe bend is located at the bend, and its axis is consistent with the axis of the main reactor; the opening direction of the branch pipe portion is parallel to the flame direction of the high-temperature plasma source (1).

2. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The high-temperature plasma source (1) is sealed to the upper end of the double-layer water-cooled sandwich chamber (2) through a flange structure to ensure that the high-temperature gas does not leak out.

3. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The bottom of the double-layer inverted conical structure of the double-layer water-cooled jacket (2) is provided with a discharge port for discharging purified graphite powder.

4. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The cooling water channels inside the double-layer water-cooled sandwich chamber (2) are arranged in a spiral shape to enhance the cooling effect and distribute the temperature evenly.

5. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The main body of the connecting pipe (3) with branch pipe is welded and fixed to the middle outer wall of the double-layer water-cooled sandwich chamber (2) to ensure structural stability.

6. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The inner diameter of the main pipe of the connecting pipe (3) with branch pipe is larger than the inner diameter of the branch pipe to balance the airflow between the main reactor and the cyclone separator.

7. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The multi-layer mesh hollow structure (4) of the branch pipe elbow is made of high temperature resistant alloy material, and its mesh hollow structure has multiple uniformly distributed through holes.

8. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The multi-layer mesh hollow structure (4) of the branch pipe elbow has gaps between its multi-layer mesh structures to control airflow distribution and prevent blockage.

9. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The bend angle of the branch pipe is 90 degrees, so that the opening direction of the branch pipe is directly opposite the flame jet direction of the high-temperature plasma source (1).

10. The structure of a main reactor with branch pipes for high-temperature graphite purification according to claim 1, characterized in that: The outer side of the double-layer water-cooled sandwich chamber (2) is provided with an insulation layer to reduce heat loss and maintain the internal temperature of the reactor.

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