Fine-particle-size graphite batch spheroidizing equipment

Abstract

The invention relates to batch spheroidizing equipment for fine-particle-size graphite. The batch spheroidizing equipment comprises a shell with a spheroidizing cavity, a grinding disc structure and a grading cage type impeller are arranged in the spheroidizing cavity, and the grading cage type impeller comprises a rotating shaft, a top frame, a chassis and a shunting fence; the rotating shaft is fixedly connected with the chassis, and the lower end of the rotating shaft extends out of the chassis and is connected with an auxiliary blade assembly and a flow guide part; the auxiliary blade assembly comprises a plurality of auxiliary blades and can enable airflow to form vortex; an annular grading flow guide assembly is arranged at the position, close to the inner wall of the spheroidizing cavity, of the periphery of the grading cage type impeller, the grading flow guide assembly comprises a plurality of flow guide blades arranged in the circumferential direction at intervals, and the plate face of each flow guide blade inclines relative to the corresponding radial direction in the spheroidizing cavity and is the same in inclination direction. According to the characteristics of the fine-particle-size graphite, the problems that in the existing fine-particle-size graphite spheroidizing process, the flow is complex, energy consumption is high, production efficiency is low, and product quality is low are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of natural graphite deep processing, in particular to a batch spheroidizing device for fine-grained graphite. Background Art

[0002] The raw material for natural graphite spheroidization is flake graphite. Due to its lamellar structure, it requires multiple spheroidization equipment to be used together, resulting in a large number of machines involved in the spheroidization process, high energy consumption, and high cost. Therefore, this equipment adopts a batch spheroidization method with one device to reduce the number of machines.

[0003] At present, the particle size of spherical graphite products shows a trend of multi-level development. There are certain differences in the balling mechanism of coarse-grained and fine-grained natural graphite. This is because fine-grained natural graphite and coarse-grained natural graphite have different volume forces, so they have different movement trajectories and residence times in the shell of the spheroidizing chamber. In the crushing process, fine-grained graphite is different from coarse-grained graphite, and the efficiency of plastic deformation is low; in the classification process, the difference between fine-grained natural graphite and coarse-grained natural graphite is also particularly obvious. Due to the different centrifugal forces on fine-grained natural graphite and coarse-grained natural graphite, the fine-grained natural graphite is subject to a smaller centrifugal force at the same rotation radius, and has a greater probability of entering the inside of the grading wheel rotor under the action of negative pressure, and being collected as tailings through the tail powder discharge port. In view of the difference between fine-grained natural graphite and coarse-grained natural graphite, adjusting the speed of the classifying impeller and the air volume parameters of the fan can improve the situation. If the particle size of the crushed particles is reduced by simply increasing the speed of the classifying impeller, the higher classification speed will inevitably increase the resistance of the impeller flow channel and block the classifying impeller, thereby increasing the output power of the fan, which may seriously damage the equipment. Therefore, it is not possible to simply adjust the parameters on the original spheroidizing equipment. It is necessary to design a high-efficiency batch spheroidizing equipment specifically for fine-grained natural graphite to solve the above technical problems.

[0004] The "background technology" section is only used to help understand the content of the present invention. Therefore, the content recorded in the "background technology" section may contain some common knowledge that is not known to those skilled in the art. The content recorded in the "background technology" section does not mean that the content or the problems to be solved by one or more embodiments of the present invention have been known or recognized by those skilled in the art before the application of the present invention. Summary of the invention

[0005] The purpose of the present invention is to develop a batch spheroidizing equipment for fine-grained graphite, which can effectively solve the problems of complex process, high energy consumption, low production efficiency and low product quality in the existing spheroidizing process of fine-grained graphite.

[0006] The object of the present invention is achieved in this way. A fine-grained graphite batch spheroidizing device includes a shell with a spheroidizing cavity; a rotatable grinding disc structure and a rotatable graded cage impeller are respectively provided at the bottom and top of the spheroidizing cavity, and the graded cage impeller includes a rotating shaft, a top frame and a bottom plate spaced apart from each other, and a diverter fence connected between the top frame and the bottom plate; the rotating shaft is fixedly connected to the bottom plate, and its lower end extends out of the bottom plate and is connected to an auxiliary blade assembly and a guide member arranged up and down, the auxiliary blade assembly includes a plurality of auxiliary blades arranged on the rotating shaft at circumferential intervals and can form a vortex in the airflow; an annular graded guide assembly is provided at the outer periphery of the graded cage impeller and close to the inner wall of the spheroidizing cavity, the graded guide assembly includes a plurality of guide blades arranged at circumferential intervals, and the plate surface of each guide blade is inclined relative to the corresponding radial direction in the spheroidizing cavity.

[0007] In a preferred embodiment of the present invention, the flow guide adopts a streamlined design, and is a teardrop-shaped structure with a rounded lower end and a gradually narrowed upper end.

[0008] In a preferred embodiment of the present invention, the guide vane is a rectangular plate body with a vertically arranged plate surface, and the inclination angle of the plate surface of the guide vane relative to the corresponding radial direction in the spheroidizing cavity is in the range of 66-75°.

[0009] In a preferred embodiment of the present invention, the diverter fence includes a plurality of diverter rods evenly spaced circumferentially, with both ends of the diverter rods respectively connected to the outer edge positions of the top frame and the bottom plate; the graded cage impeller is an inverted cone structure with an outer diameter gradually increasing from bottom to top.

[0010] In a preferred embodiment of the present invention, the rotation speed of the graded cage impeller is less than or equal to 3000 r / min.

[0011] In a preferred embodiment of the present invention, the cross-section of the shell is circular, and the inner wall of the shell includes a first cylindrical surface, a conical surface whose diameter increases from bottom to top, and a second cylindrical surface connected in sequence from bottom to top, the grinding disc structure is arranged opposite to the first cylindrical surface, and the graded cage impeller is arranged opposite to the second cylindrical surface.

[0012] In a preferred embodiment of the present invention, a feed pipe and a finished product discharge pipe can be connected in an on-off manner at a position on the side of the shell corresponding to the area between the grading cage impeller and the grinding disc structure, and an air outlet is provided at a position on the top of the shell directly opposite the grading cage impeller, and a tail powder discharge pipe can be connected in an on-off manner; a discharge valve is provided on the finished product discharge pipe, and the discharge valve can automatically open after a preset time of material spheroidization to complete the discharge; an induced draft fan is also connected to the tail powder discharge pipe, and an air supply port that can be connected to the spheroidization cavity is also provided at the bottom of the shell.

[0013] In a preferred embodiment of the present invention, a hopper is connected to the end of the feed pipe away from the shell, the hopper is connected to the first end of the screw conveyor, the second end of the screw conveyor is connected to the silo, the lower part of the silo is a cone with an inner diameter gradually tapering downward, and an air disc is provided on the inner wall of the cone.

[0014] In a preferred embodiment of the present invention, the grinding disc structure includes at least two layers of graphite spheroidizing discs arranged at intervals in the upper and lower directions, and a plurality of grinding blocks are circumferentially arranged on the top surface of the graphite spheroidizing disc; an annular gear ring is provided on the inner wall of the spheroidizing cavity facing the grinding disc structure.

[0015] In a preferred embodiment of the present invention, the cross-section of the grinding block is a parallelogram, and a plurality of annular grooves are provided on the outer wall of the grinding block from top to bottom. Part of the grinding block extends out of the outer peripheral edge of the graphite spheroidizing disk and leaves a gap with the gear ring.

[0016] In a preferred embodiment of the present invention, an impeller driving device is also provided on the top of the shell, which can be connected to the rotating shaft and used to drive the graded cage impeller to rotate; a grinding disc driving device is provided at the bottom of the shell, which can be connected to the grinding disc structure and used to drive the grinding disc structure to rotate.

[0017] As described above, the fine-grained graphite batch spheroidizing equipment of the present invention only needs one device to perform batch spheroidizing treatment on fine-grained graphite, making its shape more spherical, simplifying the process and reducing the cost. Compared with the existing equipment, which does not have a specific equipment distinction for the spheroidization of fine-grained and coarse-grained graphite, this equipment aims at the difference between fine-grained graphite and coarse-grained graphite. In the grading process, a guide piece is set to guide the rising airflow and reduce the impact of the airflow; a grading cage impeller is set, and its rotation speed and the gap of the diverter fence are adjusted to reduce the fine-grained graphite being sucked into the tail powder; auxiliary blades are set to generate vortices for the rising airflow as the grading cage impeller rotates at high speed, and the flow direction of the material in the rising process is guided to the periphery, so as to better enter the annular area, and agglomerated tail powder or finer graphite and tail powder or finer graphite attached to fine graphite are dispersed; guide blades are set to change the velocity field distribution in the annular area, so as to disperse agglomerated tail powder or finer graphite and tail powder or finer graphite attached to fine graphite. Furthermore, through the coordination of the grading cage impeller, the guide piece, the auxiliary blades and the guide blades, the grading of the materials in the spheroidizing process of the spheroidizing chamber can be made more refined; it can effectively avoid the situation that the fine-grained graphite is misclassified into tail powder, thereby reducing the ball formation rate; it can also effectively avoid the agglomeration of tail powder or finer-grained graphite and being treated as fine-grained graphite and mixed into the fine-grained graphite product, and avoid the tail powder or finer-grained graphite attached to the fine-grained graphite and then entering the spheroidizing zone for curling and compacting and being mixed into the fine-grained finished product, thereby causing the fine-grained spherical graphite product to have low tap density, large specific surface area, irregular morphology, low finished product qualification rate and failure to meet product specification requirements. The qualified ball formation rate of fine-grained graphite products is effectively improved, and the production efficiency and product quality are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings are intended only to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0019] Figure 1 This is a schematic structural diagram of the fine-grained graphite batch spheroidizing equipment provided by the present invention.

[0020] Figure 2 A schematic structural diagram of the graded cage impeller provided by the present invention.

[0021] Figure 3 The structure diagram of the graded cage impeller and guide vane provided by the present invention is shown in FIG. Figure 1 .

[0022] Figure 4 The structure diagram of the graded cage impeller and guide vane provided by the present invention is shown in FIG. Figure 2 .

[0023] Figure 5a A top view of the graphite spheroidizing disk and one of the grinding blocks provided by the present invention.

[0024] Figure 5b A three-dimensional diagram of the grinding block provided by the present invention.

[0025] Figure 5c This is a schematic diagram of the cooperation between the graphite spheroidizing disc, grinding block and gear ring provided by the present invention.

[0026] Figure 6 The present invention provides a schematic structural diagram of a spherical graphite batch spheroidizing device connected to an induced draft fan, a tail powder dust collector, and a finished product dust collector.

[0027] Figure 7 This is a schematic structural diagram of the silo provided by the present invention.

[0028] Figure 8 The scanning electron microscope image of the raw material used in the experiment provided by the present invention is: Figure 8 The scale bar is 50 μm.

[0029] Fig. 9 The second scanning electron microscope image of the raw material used in the experiment provided by the present invention is Fig. 9 The scale bar is 4 μm.

[0030] Fig.10 The scanning electron microscope image 1 of the product obtained after the raw material provided by the present invention is tested according to the test parameter a, Fig.10 The scale bar is 50 μm.

[0031] Fig.11 The second scanning electron microscope image of the product obtained after the raw material provided by the present invention is tested according to the test parameter a. Fig.11 The scale bar is 5 μm.

[0032] Fig.12 The scanning electron microscope image 1 of the product obtained after the raw material provided by the present invention is tested according to the test parameter b, Fig.12 The scale bar is 50 μm.

[0033] Fig.13 The second scanning electron microscope image of the product obtained after the raw material provided by the present invention is tested according to the test parameter b, Fig.13 The scale bar is 5 μm.

[0034] Description of Figure Numbers:

[0035] 1. Shell; 11. Spheroidizing cavity; 121. First cylindrical surface; 122. Conical surface; 123. Second cylindrical surface; 13. Feed pipe; 131. Hopper; 132. Feed valve; 14. Finished product discharge pipe; 15. Air outlet; 16. Tail powder discharge pipe; 17. Air supply port; 18. Base frame; 19. Gear ring;

[0036] 2. Grinding disc structure; 21. Graphite spheroidizing disc; 22. Grinding block; 221. Annular groove; 222. Edges and corners; 23. Driven pulley; 24. Transmission shaft; 25. Support cylinder; 26. Bearing; 27. Diverter ring;

[0037] 3. Grading cage impeller; 31. Top frame; 32. Chassis; 33. Diverter fence; 34. Rotating shaft; 35. Auxiliary blades; 36. Flow guide; 37. Flow guide blades; 38. Impeller drive device; 381. Impeller drive motor;

[0038] 4. Silo; 41. Air disc for flow assistance; 42. Screw conveyor; 5. Vacuum conveyor;

[0039] 6. Induced draft fan; 7. Tail powder dust collector; 8. Finished product dust collector. DETAILED DESCRIPTION

[0040] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0041] like Figures 1 to 13 As shown, this embodiment provides a fine-grained graphite batch spheroidizing device, including a housing 1 with a spheroidizing chamber 11; a rotatable grinding disc structure 2 and a rotatable grading cage impeller 3 are respectively provided at the bottom and top of the spheroidizing chamber 11, and the grading cage impeller 3 includes a rotating shaft 34, a top frame 31 and a bottom plate 32 spaced apart from each other, and a diverter fence 33 connected between the top frame 31 and the bottom plate 32; the rotating shaft 34 is fixedly connected to the bottom plate 32, and its lower end extends out of the bottom plate 32 and is connected to the top and bottom arranged Auxiliary blade assembly and guide 36, the auxiliary blade assembly includes a plurality of auxiliary blades 35 arranged on the rotating shaft 34 at circumferential intervals and can make the airflow form a vortex to disperse the graphite material to the periphery; an annular graded guide assembly is provided at the periphery of the graded cage impeller 3 and close to the inner wall of the spheroidizing chamber 11, the graded guide assembly includes a plurality of guide blades 37 arranged at circumferential intervals, and the plate surface of each guide blade 37 is inclined relative to the corresponding radial direction in the spheroidizing chamber 11 and the inclination direction is the same.

[0042] Natural spherical graphite is a potato-like spherical graphite product obtained by continuously crushing and spheroidizing natural flake graphite (lamellar structure) as raw material. Spherical graphite products can be divided into fine-grained graphite products and coarse-grained graphite products according to particle size. In the prior art, a large number of devices are required to crush and spheroidize the flake graphite raw materials. The front multiple devices mainly crush the raw materials, and irregular fine-grained graphite is obtained after classification. The back multiple devices are connected in series to perform joint spheroidization on the fine-grained graphite, so that the fine-grained graphite reaches a certain sphericity and tap density, and obtains fine-grained spherical graphite products, which requires more equipment. In this embodiment, a batch spheroidization device for fine-grained graphite is used to replace multiple devices for spheroidizing fine-grained graphite, which can effectively simplify the spheroidization process.

[0043] The entire batch spheroidizing equipment is mainly used to spheroidize fine-grained graphite. The raw material is fine-grained graphite with irregular morphology. During production, the raw material is added into the spheroidizing cavity 11 for internal circulation, and the material is discharged according to the preset time to obtain fine-grained spherical graphite products. In the spheroidizing chamber 11, from bottom to top, it is divided into a shaping zone, a transition zone and a grading zone. The shaping zone is arranged opposite to the grinding disc structure 2, and the grading zone is arranged opposite to the grading cage impeller 3. After the raw material is shaped by kneading, compacting, curling, etc. in the shaping zone by the grinding disc structure 2, it flows upward under the action of negative pressure suction and is sucked to the annular zone between the grading cage impeller 3 and the inner wall of the spheroidizing chamber 11 in the grading zone. During this ascending process, the guide member 36 can guide the airflow, and the auxiliary blades 35 and the guide blades 37 can make the material more dispersed. The graphite material with very fine particle size (generally referred to as tail powder) enters the grading cage impeller 3 and is sucked away and discharged. The graphite material with a larger particle size is not sucked away and falls on the grinding disc structure 2 for secondary shaping, and circulates continuously in the spheroidizing chamber 11.

[0044] Therefore, the fine-grained graphite batch spheroidization equipment in this embodiment only needs one device to perform batch spheroidization on fine-grained graphite with irregular morphology, which simplifies the process and reduces costs. Compared with the existing equipment that does not specifically distinguish between fine-grained and coarse-grained graphite spheroidization, this equipment is specifically for the spheroidization of fine-grained graphite. During the grading process, a guide member 36 is set to guide the rising airflow and reduce the impact of the airflow; a grading cage impeller 3 is set, and its rotation speed and the gap of the diverter fence 33 are adjusted to reduce the fine-grained graphite being sucked into the tail powder; an auxiliary blade 35 is set, which can generate vortexes for the rising airflow as the grading cage impeller 3 rotates at high speed, and guides the flow direction of the material in the rising process to the periphery, so that it can better enter the annular area, and can disperse the agglomerated tail powder or finer-grained graphite and the tail powder or finer-grained graphite attached to the fine-grained graphite; a guide blade 37 is set to change the velocity field distribution of the annular area, and can disperse the agglomerated tail powder or finer-grained graphite and the tail powder or finer-grained graphite attached to the fine-grained graphite.

[0045] Furthermore, through the cooperation of the grading cage impeller 3, the guide member 36, the auxiliary blades 35 and the guide blades 37, the grading of the materials in the spheroidizing process of the materials in the spheroidizing chamber 11 can be made more refined; it can effectively avoid the situation where the fine-grained graphite is misclassified into tail powder, thereby reducing the ball formation rate; it can also effectively avoid the agglomeration of tail powder or finer-grained graphite and being treated as fine-grained graphite and mixed into the fine-grained graphite product, and avoid the tail powder or finer-grained graphite attached to the fine-grained graphite and then entering the spheroidizing zone for curling and compacting and being mixed into the fine-grained finished product, thereby causing the fine-grained spherical graphite product to have low tap density, large specific surface area, irregular morphology, low finished product qualification rate and failure to meet product specification requirements. The qualified ball formation rate of fine-grained graphite products is effectively improved, and the production efficiency and product quality are improved.

[0046] It should be noted that the particle size volume distribution of the fine-grained spherical graphite product (i.e., fine-grained graphite finished product) mentioned in this embodiment satisfies the median particle size D 50 The particle size volume distribution of coarse-grained spherical graphite products meets the median particle size D 50 >23 μm. The specific classification of the particle size of fine-grained spherical graphite products and coarse-grained spherical graphite products shall be based on the range known in the industry. It can be understood that the spherical graphite products mentioned in this article are not completely standard spheres, but may also refer to ellipsoids or quasi-spheres. The graphite in this case mainly refers to natural graphite. Finer-grained graphite can also be called fine powder, and its particle size is smaller than that of fine-grained graphite and larger than that of tail powder.

[0047] Furthermore, the guide member 36 preferably adopts a teardrop-shaped structure with a rounded lower end and a gradually narrowed upper end.

[0048] Reference Figure 2 and Figure 3 The guide member 36 is arranged at the bottom end of the rotating shaft 34 and is coaxially arranged with the rotating shaft 34. The water drop-shaped structure is a structure whose diameter gradually increases from top to bottom and then gradually decreases, and whose outer surface has a smooth transition and is very gentle, and whose shape is similar to that of a water drop. The water drop-shaped structure, due to its unique streamlined design, can effectively guide the flow direction of the rising airflow rising from the lower end, reduce eddy currents and resistance, improve flow efficiency, and make the rising airflow and the materials in the rising process flow upward more smoothly; at the same time, the water drop-shaped structure can reduce stress concentration, and at the same time, the stress concentration can be further reduced through geometric shapes such as rounding, thereby improving the durability of the water drop-shaped structure.

[0049] The graded flow guide assembly is arranged in the annular area and close to the inner wall of the spheroidizing cavity 11. A plurality of flow guide blades 37 are evenly spaced along the circumference of the graded flow guide assembly. The specific number of flow guide blades 37 is determined according to actual needs. For example, a total of 75 flow guide blades 37 are arranged in this embodiment.

[0050] Each guide blade 37 is of the same size and is a rectangular plate. The plate surface of each guide blade 37 is vertically arranged, and the length direction of each guide blade 37 is arranged along the vertical direction. The width direction of each guide blade 37 is inclined relative to the corresponding radial direction in the graded guide assembly and the inclination direction is the same. Specifically, it is arranged to be inclined relative to the corresponding radial direction of the spheroidizing cavity 11 according to the rotation direction from the inside of the spheroidizing cavity 11 to the outside toward the graded cage impeller 3; for example, in this embodiment, the graded cage impeller 3 rotates clockwise, and the width direction of each guide blade 37 is inclined relative to the corresponding radial direction on the cross section of the spheroidizing cavity 11 from the inside of the spheroidizing cavity 11 to the outside in the clockwise direction and is inclined at a preset angle.

[0051] If the preset inclination angle is too small, the movement speed of the material in the classification area will be reduced, and the movement of the material will be blocked, thereby reducing the classification accuracy; if the preset inclination angle is too large, the stability of the flow field in the classification area will be destroyed, and the flow diversion effect will not be achieved, which is not conducive to the classification of the material. Therefore, in this embodiment, the inclination angle range of the plate surface of the guide blade 37 relative to the corresponding radial direction in the spheroidizing cavity 11 is preferably 66-75°. Under this parameter, it can be more conducive to the dispersion of the material, more conducive to the fine classification of the material, and more conducive to improving the qualified balling rate of fine-grained spherical graphite products, thereby improving product quality.

[0052] The internal flow state of the spheroidizing cavity 11 is of medium intensity turbulence. Due to the inherent dissipative characteristics of turbulence, in the turbulent flow field of the classification zone, the largest scale eddy will dissipate energy into smaller and smaller eddies until the energy is lost as heat into the fluid at the smallest scale. The turbulence dissipation of the guide vane 37 is smaller than that of the guide vane 37, and the smaller turbulence dissipation rate is more conducive to the stability of the flow field and the reduction of energy consumption in the production process of fine-grained natural graphite, so as to improve the classification efficiency.

[0053] Further, see Figure 2 The diverter fence 33 includes a plurality of diverter rods evenly spaced circumferentially, and the two ends of the diverter rods are respectively connected to the outer edge positions of the top frame 31 and the bottom plate 32; the graded cage impeller 3 is an inverted cone structure with an outer diameter gradually increasing from bottom to top.

[0054] The bottom plate 32 is a disc structure, the top frame 31 can be a hollow circular frame or a ring structure, the outer diameter of the top frame 31 is larger than the outer diameter of the bottom plate 32, and the entire graded cage impeller 3 forms an inverted cone structure with a large top and a small bottom. The diverter rod can be a wear-resistant steel rod, and the specific number can be determined according to needs. For example, in this embodiment, a total of 70 diverter rods are provided. The diverter rod can be a cylindrical rod, or it can be arranged in accordance with Figure 2 Shown in FIG. 1 are relatively thin rectangular rods.

[0055] In this embodiment, for the spheroidization of fine-grained graphite, a guide member 36, an auxiliary blade 35 and a guide blade 37 are specially provided in the device, which can make the material more dispersed and is more conducive to improving the classification effect of the material. Therefore, the rotation speed of the classification cage impeller 3 does not need to be so high. In this embodiment, the rotation speed of the classification cage impeller 3 is less than or equal to 3000r / min, and more preferably 1500-2500r / min. At this relatively low rotation speed, the fine-grained graphite can be prevented from being sucked away and becoming tail powder, thereby improving the yield rate.

[0056] Further, see Figure 1 The cross section of the shell 1 is circular, and the inner wall of the shell 1 includes a first cylindrical surface 121, a conical surface 122 and a second cylindrical surface 123 which are sequentially connected from bottom to top, the grinding disc structure 2 is arranged opposite to the first cylindrical surface 121, and the graded cage impeller 3 is arranged opposite to the second cylindrical surface 123.

[0057] The parts of the shell 1 corresponding to the shaping zone and the grading zone are both cylindrical shells, and the part of the shell 1 corresponding to the transition zone is an inverted cone shell, and the transition zone can guide the airflow. The area between the grading cage impeller 3 and the grinding disc structure 2 in the spheroidizing cavity 11 (i.e., the transition zone) is a hollow cavity, and no other components are set, which will not affect the circulation effect of the airflow in the spheroidizing cavity 11. Compared with other components in the transition zone, the feeding amount is more and the production capacity is higher.

[0058] Reference Figure 1 and Figure 6 A feed pipe 13 and a finished product discharge pipe 14 can be connected in an on-off manner at a position on the side of the shell 1 corresponding to the area between the grading cage impeller 3 and the grinding disc structure 2. An air outlet 15 is provided at a position on the top of the shell 1 facing the grading cage impeller 3, and a tail powder discharge pipe 16 can be connected in an on-off manner.

[0059] The feed pipe 13 and the finished product discharge pipe 14 are located on both sides of the transition zone of the shell 1. The feed pipe 13 is used to add fine-grained graphite with irregular morphology, and the finished product discharge pipe 14 is used to output fine-grained graphite products. A discharge valve is provided on the finished product discharge pipe 14 and is electrically connected to a control device. The discharge valve can be controlled to automatically open and close according to the system preset or actually required spheroidization time of the fine-grained spherical graphite product.

[0060] The air outlet 15 is opened at the top center position of the shell body 1, facing the top frame 31 of the grading cage impeller 3. The first end of the tail powder discharge pipe 16 is arranged on the top of the shell body 1 and is connected with the air outlet 15. The tail powder sucked into the grading cage impeller 3 enters the inner cavity surrounded by the diversion fence 33, and then flows upward from the top frame 31 through the air outlet 15 into the tail powder discharge pipe 16.

[0061] The tail powder discharge pipe 16 is also connected to an induced draft fan 6 , and an air supply port 17 that can communicate with the spheroidizing cavity 11 is also provided at the bottom of the shell 1 .

[0062] The induced draft fan 6 is connected to the second end of the tail powder discharge pipe 16. Under the action of the induced draft fan 6, negative pressure suction can be generated at the air outlet 15, and the particles spheroidized by the grinding disc structure 2 flow upward under the action of the negative pressure suction. The air supply port 17 is located below the grinding disc structure 2, generally arranged on the bottom side wall of the shell 1, and a total of two air supply ports 17 can be set. The air supply port 17 has a square cross-section, and a plug plate is provided in the air supply port 17, so that the opening and closing size can be manually adjusted. The air supply port 17 can increase the residence time of fine-grained natural graphite in the annular area, and will have the effect of dispersing materials to a certain extent, thereby reducing the misclassification of fine-grained spherical graphite products.

[0063] Furthermore, one end of the feed pipe 13 away from the shell 1 is also connected to a hopper 131 , the hopper 131 is connected to a first end of a screw conveyor 42 , and a second end of the screw conveyor 42 is connected to a silo 4 .

[0064] The axis of the feed pipe 13 is generally arranged to be inclined downward from the hopper 131 to the shell 1, and a feed valve 132 is installed on the feed pipe 13 to control the on and off here. The screw conveyor 42 is arranged above the hopper 131, and the silo 4 can be a metering silo. When the batch spheroidizing device is in the spheroidizing state, the feed valve 132 is in a closed state. When the batch spheroidizing device completes the spheroidization and the finished product is discharged, the feed valve 132 is in an open state, and the fine-grained graphite with irregular weight and morphology set according to the metering silo enters the spheroidizing cavity 11 from the feed pipe 13 for internal circulation.

[0065] Reference Figure 7 The lower part of the silo 4 is a conical body with an inner diameter tapering downward, and a flow-assisting air disc 41 is provided on the inner wall of the conical body. The flow-assisting air disc 41 can play the role of flow-assisting and arch-breaking, so as to prevent the fine-grained graphite from hanging on the wall and forming an arch under the action of the surface tension and friction of the material after being stored in the silo 4 for a certain period of time due to its large surface tension, thereby causing the silo 4 to be blocked.

[0066] Further, see Figure 1 The grinding disc structure 2 includes at least two layers of graphite spheroidizing discs 21 arranged at intervals in the upper and lower directions, and a plurality of grinding blocks 22 are arranged at intervals in the circumferential direction on the top surface of the graphite spheroidizing disc 21; an annular gear ring 19 is arranged on the inner wall of the spheroidizing cavity 11 at a position facing the grinding disc structure 2. Each graphite spheroidizing disc 21 is connected and fixed to the transmission shaft 24 described below; the use of multiple layers of graphite spheroidizing discs 21 has a stronger spheroidizing ability and a higher spheroidizing efficiency.

[0067] As a preference, refer to Figure 5a , Figure 5b and Figure 5c The cross section of the grinding block 22 is a parallelogram, and a plurality of annular grooves 221 are provided on the outer wall of the grinding block 22 from top to bottom. Part of the grinding block 22 extends out of the outer peripheral edge of the graphite spheroidizing disk 21 and leaves a gap with the gear ring 19.

[0068] Specifically, the graphite spheroidizing disk 21 is a circular disk body, and the rotation direction of the graphite spheroidizing disk 21 is opposite to the rotation direction of the graded cage impeller 3. The grinding block 22 is arranged close to the outer peripheral edge of the graphite spheroidizing disk 21, and a part of the grinding block 22 extends out of the outer peripheral edge of the graphite spheroidizing disk 21 and is located in the space between the graphite spheroidizing disk 21 and the gear ring 19. A threaded hole is opened on the grinding block 22, which can be fixed to the graphite spheroidizing disk 21 by screws. The cross section of the grinding block 22 along the vertical direction is a parallelogram, and the parallelogram has an acute angle and an obtuse angle. When arranged, it is preferred that one of the acute angles and one of the adjacent obtuse angles of the parallelogram extend out of the outer peripheral edge of the graphite spheroidizing disk 21, and the sides between the acute angle and the obtuse angle extending out of the graphite spheroidizing disk 21 in the parallelogram are arranged in an inclined manner from the inside of the graphite spheroidizing disk 21 to the outside in the opposite direction of the rotation direction of the graphite spheroidizing disk 21 relative to the corresponding radial direction of the graphite spheroidizing disk 21, and the other set of opposite sides in the parallelogram are parallel to the corresponding radial direction of the graphite spheroidizing disk 21. For example, referring to Figure 5a , the graphite spheroidizing disk 21 rotates counterclockwise, the parallelogram has two acute angles and two obtuse angles, one of the acute angles A and one of the adjacent obtuse angles B extend out of the peripheral edge of the graphite spheroidizing disk 21, the side L1 between the acute angle A and the obtuse angle B is inclined clockwise from the inside of the graphite spheroidizing disk 21 to the outside relative to the corresponding radial direction of the graphite spheroidizing disk 21, and the two sides L2 adjacent to the side L1 in the parallelogram are parallel to the corresponding radial direction of the graphite spheroidizing disk 21. The component speed of the impact process between the graphite and the grinding block 22 can be directed to the gear ring 19, thereby improving the spheroidizing efficiency.

[0069] The annular gap between the grinding block 22 and the gear ring 19 is the area where the spheroidization process mainly occurs. If the gap between the end of the grinding block 22 and the gear ring 19 is larger, the graphite particles may fly too long after being impacted and fail to be fully impacted. On the contrary, if the number of collisions between the graphite particles and the end of the grinding block 22 and the ring gear 19 increases, the graphite particles may be broken; in this device, the gap between the two is limited to 3mm based on the product characteristics of fine-grained spherical graphite (specifically, the minimum gap between the grinding block 22 and the ring gear 19, that is, the gap between the farthest end of the grinding block 22 away from the center of the graphite spheroidizing disk 21 and the ring gear 19), so as to be suitable for the spheroidization of fine-grained graphite. The gap area is the main spheroidization area, and the graphite is rubbed and deburred in this area; the bottom side of the spheroidizing chamber 11 is provided with the above-mentioned air supply port 17. In order to maintain the negative pressure state in the spheroidizing chamber shell 1, the air supply port 17 is provided to ensure that there is a corresponding air intake mechanism to replenish the extracted gas, so as to maintain the pressure balance in the spheroidizing chamber 11.

[0070] In this embodiment, in view of the differences between fine-grained graphite and coarse-grained graphite during the spheroidization process, a multilayer graphite spheroidizing disk 21 is designed to enhance the spheroidization efficiency of fine-grained graphite; based on the fact that fine-grained graphite has fewer internal cracks and defects and the spheroidization efficiency of fine-grained graphite is low during plastic deformation, a parallelogram-shaped grinding block 22 is provided, the angle of the parallelogram is smaller and sharper, and the component velocity of the impact process between the graphite and the grinding block 22 points to the ring gear 19, the movement distance of the graphite particles to the ring gear 19 is shorter, thereby enhancing the spheroidization efficiency of the fine-grained graphite. An annular groove 221 is provided on the grinding block 22, which can make the contact surface between the graphite particles and the grinding block 22 larger. In the gap area between the grinding block 22 and the gear ring 19, the airflow direction is from bottom to top, and the corners 222 at the junction of the annular groove 221 and the outer surface of the grinding block 22 can produce a striking effect on the graphite particles, so that the efficiency of plastic deformation of fine-grained graphite is better improved during the process of graphite particles being driven by the airflow, and the spheroidization effect is improved. At the same time, according to the characteristics of fine particle size, the gap between the farthest end of the grinding block 22 away from the center of the graphite spheroidization disk 21 (that is, the sharp tip of the parallelogram located outside the graphite spheroidization disk 21) and the gear ring 19 is shortened and designed to be 3mm. This is more conducive to improving the characteristic that fine-grained graphite is not easy to be plastically deformed, and the spheroidization efficiency of fine-grained graphite is increased.

[0071] Further, see Figure 1 An impeller driving device 38 is also provided on the top of the shell 1, and the impeller driving device 38 can be connected to the rotating shaft 34 and used to drive the graded cage impeller 3 to rotate; a grinding disc driving device is provided at the bottom of the shell 1, and the grinding disc driving device can be connected to the grinding disc structure 2 and used to drive the grinding disc structure 2 to rotate.

[0072] The impeller driving device 38 includes an impeller driving motor 381, which is arranged on the top of the shell 1 and above the tail powder discharge pipe 16. The upper end of the rotating shaft 34 passes through the above-mentioned air outlet 15 and the tail powder discharge pipe 16 in sequence and is connected to the driving motor.

[0073] The grinding disc driving device includes a transmission assembly and a grinding disc driving motor. The transmission assembly includes an axially vertically arranged driving pulley and a driven pulley 23, an annular belt connected between the driving pulley and the driven pulley 23, and an axially vertical transmission shaft 24. The annular belt is tensioned in the horizontal direction. The lower end of the transmission shaft 24 is connected to the driven pulley 23. The upper end of the transmission shaft 24 passes through the bottom of the housing 1 and is connected to the graphite spheroidizing disk 21 at the bottom. Specifically, a keyway is provided on the upper end side wall of the transmission shaft 24, and the graphite spheroidizing disk 21 is connected to the transmission shaft 24 through a key. The grinding disc driving motor is connected to the driving pulley to drive the driving pulley to rotate, and then transmits power to the driven pulley 23 through the annular belt. The rotation of the driven pulley 23 drives the transmission shaft 24 to rotate, and the torque is transmitted from the transmission shaft 24 to the graphite spheroidizing disk 21 through the key to drive the graphite spheroidizing disk 21 to rotate.

[0074] A chassis 18 is also connected to the bottom of the housing 1 for supporting the ground, and the grinding disc drive motor is arranged on the chassis 18. A support cylinder 25 is also arranged at the bottom center of the housing 1, and the top of the support cylinder 25 extends into the housing 1. A bearing 26 is arranged in the support cylinder 25. The upper end of the transmission shaft 24 passes through the bearing 26 and then extends into the housing 1. The transmission shaft 24 provides support and bears the weight and force of the driven pulley 23. The bearing 26 significantly reduces the friction between the transmission shaft 24 and other components while bearing loads from all directions and fixing the position of the transmission shaft 24. A diverter ring 27 can also be arranged in the bottom of the housing 1 and below the grinding disc structure 2. The diverter ring 27 is fixed to the transmission shaft 24 through a threaded connection.

[0075] Of course, the impeller driving device 38 and the grinding disc driving device may also adopt other structural modes, as long as it is convenient to drive the graded cage impeller 3 to rotate and drive the grinding disc structure 2 to rotate. This embodiment is only for illustration.

[0076] A grading cage impeller 3 is provided in the spheroidizing chamber 11, and the grading cage impeller 3 is located above the graphite spheroidizing disk 21 and close to the top of the spheroidizing chamber 11, so that the tail powder with extremely fine particle size that can no longer be spheroidized can be discharged; the grading cage impeller 3 is connected to the impeller drive motor 381 through the rotating shaft 34, and the tail powder discharge pipe 16 is arranged between the grading cage impeller 3 and the impeller drive motor 381.

[0077] Generally, a tail powder dust collector 7 is connected to the middle of the tail powder discharge pipe 16, and a finished product dust collector 8 is connected to the end of the finished product discharge pipe 14 away from the housing 1. The discharge port of the finished product dust collector 8 is the outlet of the fine-grained spherical graphite product, and the ash discharge port of the finished product dust collector 8 is connected to the feed port of the tail powder dust collector 7 through a corresponding pipeline. A vacuum conveyor 5 can also be connected to the feed port at the top of the silo 4.

[0078] Further, the classification mechanism of fine-grained graphite is analyzed as follows:

[0079] Not only does the fineness of different flakes affect the spheroidization process, but the current particle size of spheroidized graphite products also shows a multipolar development trend. The reason is that the difference in the magnitude of the force on graphite of different particle sizes leads to different motion trajectories in the spheroidization chamber 11. When the batch spheroidization equipment is in operation, the induced draft fan 6 connected to the tail powder discharge pipe 16 generates negative pressure, forming an upward airflow inside the spheroidization chamber 11. After the material is fed from below and spheroidized through the spheroidization area where the graphite spheroidization disk 21, the grinding block 22, and the gear ring 19 are located, due to the different volume forces of materials of different particle sizes, the collision of coarse-grained graphite in the spheroidization area is very obvious, while fine-grained graphite only stays in the spheroidization area for a short time. After passing through the spheroidizing zone, the material continues to rise under the negative pressure of the induced draft fan 6 and the swirl generated by the high-speed rotation of the graphite spheroidizing disk 21, and enters the transition zone between the grading zone and the spheroidizing zone where the grading cage impeller 3 is located. There is no obvious boundary between the transition zone and the spheroidizing zone and the grading zone. The function of the transition zone is to make the particles flow back and forth in the spheroidizing cavity 11. After graphite of different particle sizes enters the transition zone with the airflow, the movement trajectory changes. Graphite with smaller particle size has better ability to follow the airflow, and the particle movement trajectory in the transition zone is smooth and the residence time in the transition zone is short; graphite with larger particle size has poor ability to follow the airflow, and the movement trajectory of coarse-grained graphite in the transition zone is disordered, and the movement trajectory of finer-grained graphite in the transition zone is longer, and the time of circling and staying in the transition zone is longer.

[0080] The difference in graphite ball formation is not only reflected in the different movement trajectories of graphite in the balling zone and the transition zone, but is also particularly evident in the classification process. The graphite entering the batch balling equipment and being classified is a probabilistic event. When the material rises from the transition zone to the classification zone, the material will be horizontally subjected to the outward centrifugal force generated by the high-speed rotation of the classification cage impeller 3. , whose expression is:

[0081]

[0082] In the formula, is the density of graphite particles, r is the rotation radius of the graphite particles in the grading zone, w is the angular velocity of the graphite particles, It is the diameter of spherical graphite particles with the same volume as graphite particles.

[0083] At the same time, the high-speed rotating airflow will generate a horizontal drag force (F Y ), whose expression is:

[0084]

[0085] In the formula, is the density of the gas around the graphite particles, V is the relative speed between the graphite particles and the surrounding gas, A is the projected area of ​​the graphite particles in the direction of motion (i.e., vertical direction), is the drag coefficient. The laminar flow zone, transition zone, and turbulent flow zone with different Reynolds numbers (Re) have different drag coefficient values. Since the flow state inside the spheroidizing cavity 11 is a medium-intensity turbulent flow, the turbulent flow zone =0.44.

[0086] In the vertical direction, the graphite in the classification area is subject to the gravitational force of the negative pressure of the induced draft fan 6 (ignoring the air volume loss), the suspension force of the graphite particles suspended in the air, and the gravity. The resultant force on the graphite particles is expressed as

[0087]

[0088] Where Q is the suction force of the induced draft fan 6, is the efficiency of the induced draft fan 6. The above formulas are all for the force analysis of a single graphite particle.

[0089] According to the force balance, F 离心 = F Y , the following classification particle size formula can be obtained:

[0090]

[0091] The classification particle size formula can be used to calculate the particle size (equivalent particle size) of the classified fine-grained graphite products.

[0092] Since the mass of fine-grained graphite is smaller than that of coarse-grained graphite, it can be seen from the above formula that the centrifugal force it is subjected to in the horizontal direction is small at the same rotation radius, and it has a greater probability of entering the interior of the grading cage impeller 3 under the action of the horizontal drag force, and entering the tail powder dust collector 7 through the air outlet 15 and the tail powder discharge pipe 16 for collection to become tail materials; graphite materials with larger particle sizes are subjected to greater centrifugal force at the same rotation radius, so they have a greater probability of being thrown out of the periphery of the grading cage impeller 3, falling into the transition zone and then passing through the spheroidization zone for re-spheroidization.

[0093] In view of the difference between coarse-grained and fine-grained spherical graphite, although adjusting the rotation speed of the grading cage impeller 3 and the air volume parameters of the induced draft fan 6 can improve the difference between coarse-grained and fine-grained graphite in the grading process, taking fine-grained graphite as an example, if the particle size of the crushed particles is reduced by simply increasing the rotation speed of the grading cage impeller 3, the higher grading speed will inevitably cause an increase in the impeller flow channel resistance, thereby leading to an increase in the output power of the induced draft fan 6.

[0094] In particular, the particle size of fine-grained spherical graphite is generally around 10μm. The finer the particle size, the larger the specific area and the greater the surface energy. The high surface energy causes the tail powder or finer-grained graphite to agglomerate into fine-grained spherical graphite agglomerates, or the tail powder or finer-grained graphite adheres to the fine-grained graphite; the fine-grained spherical graphite agglomerates of the tail powder or finer-grained graphite, or the tail powder or finer-grained graphite adhered to the fine-grained graphite, will be classified into the fine-grained product together, forming a "fishhook effect" in the Tromp curve, thereby causing the classification efficiency of the fine-grained graphite to decrease and affecting the product qualification rate. Due to the agglomeration of the tail powder or finer-grained graphite itself, or adhesion to spherical graphite of other particle sizes, the dispersion of the spherical graphite in the body becomes worse, which reduces the classification accuracy.

[0095] In this embodiment, by cooperating the grading cage impeller 3, the guide member 36, the auxiliary blades 35 and the guide blades 37 and setting the various structural parameters, the particle classification during the spheroidization treatment of the material in the spheroidization chamber 11 can be more refined, and the qualified spheroidization rate of fine-grained natural graphite is effectively improved.

[0096] In order to better reflect the effect of the equipment, some test data are provided below:

[0097] In order to explore the material properties and evolution law of the batch spheroidization equipment of this embodiment when spheroidizing fine-grained quasi-spheroidal graphite, the second-mouth material with a particle size distribution of 8-10μm was used as the raw material, and the batch spheroidization equipment was used to carry out experiments according to different test parameters, and the continuous operation was carried out under a single operating parameter. The particle size, tap density and partial morphology evolution results are shown in Tables 1 and Figure 8 and Fig.13 shown.

[0098] pass Figures 8 to 13 It can be seen from the SEM image that the surface of the fine-grained spherical graphite after crushing and spheroidizing by the batch spheroidizing equipment is very smooth, and there are no smaller tail powder particles attached to its surface, indicating that under the action of the guide member 36, the auxiliary blade 35 and the guide blade 37, the material adhering to the surface of the fine-grained spherical graphite due to its high surface energy can be broken up in the grading area to achieve fine grading.

[0099] Table 1 Test parameters and results of fine particle size two-port material entering the batch spheroidization equipment in this example

[0100]

[0101] Among them, the host frequency in Table 1 refers to the frequency of rotation of the grinding disc structure 2, the classification frequency refers to the frequency of rotation of the classification cage impeller 3, and the fan frequency refers to the frequency of the index fan 6. The yield is also the yield, that is, the ball formation rate, which is equal to the discharge amount / feed amount.

[0102] By analyzing the test results in Table 1, it can be seen that the product particle size did not further decrease, and the tap density of the product increased by about 0.4 g / cm after 10 minutes of batch spheroidization under the two test parameters. 3 , indicating that the fine-grained graphite is no longer broken in the equipment, and is mainly spheroidized, and the equipment has a good compaction effect. Under the action of the grading cage impeller 3, the material does not need to significantly increase the grading frequency, and the raw material can avoid a large amount of entering the tailings through the grading cage impeller 3. It repeatedly collides and embeds into a spheroidization cavity 11, and reaches a spheroidization rate of more than 70%. At the same time, the particle size distribution increases, the tap density increases, and the morphology is more regular. The results show that the spheroidization effect of the equipment of this embodiment dedicated to fine-grained graphite is good, and 20 kg of material can be processed in 2.5 minutes. Considering the single 1 minute material entry and discharge time, the single machine processing capacity can reach 340 kg / h, and the tap density of the spherical graphite product can be increased from 0.48 g / cm 3 Increased to 0.7 g / cm 3 The yield is kept above 75%.

[0103] In summary, the equipment of this embodiment is a highly efficient batch spheroidization equipment specially designed for fine-grained spherical graphite, and has the following advantages compared with the prior art:

[0104] (1) In the existing graphite spheroidization technology, there is no dedicated spheroidization equipment for fine-grained spheroidal graphite, resulting in insufficient classification in the process of batch spheroidization of fine-grained graphite, resulting in fine-grained spheroidal graphite being classified into tail powder, or tail powder or finer spherical graphite agglomerates and is regarded as fine-grained products, or tail powder or finer particles are attached to fine-grained spherical graphite and then enter the spheroidization zone, resulting in failure to meet product specifications, resulting in low qualified spheroidization rate of fine-grained spherical graphite products, and low yield. The equipment of this embodiment uses a grading cage impeller 3 to perform targeted classification of fine particles, reduces the fine-grained spherical graphite being sucked into tail powder, and disperses the agglomerated fine-grained spherical graphite through the guide member 36, the auxiliary blade 35, the guide blade 37 and the supplementary air, thereby improving the problem of low qualified spheroidization rate of fine-grained spherical graphite.

[0105] (2) In view of the difference between fine-grained graphite and coarse-grained graphite during the spheroidizing process, the equipment is designed with a multi-layer graphite spheroidizing disk 21, thereby enhancing the spheroidizing efficiency of fine-grained graphite. Based on the fact that fine-grained graphite has fewer internal cracks and defects and has low efficiency in the plastic deformation process, a parallelogram-shaped grinding block 22 is provided. An annular groove 221 is provided on the grinding block 22. The corners 222 corresponding to the annular groove 221 can better improve the efficiency of plastic deformation of fine-grained graphite. At the same time, in view of the characteristics of fine grains, the gap between the farthest end of the grinding block 22 away from the center of the graphite spheroidizing disk 21 and the gear ring 19 is shortened to 3 mm. The graphite spheroidizing disk 21 is driven to rotate at a high speed by the transmission component, so that the material passes through the feed pipe 13 and is hit by the grinding block 22 and the gear ring 19 installed on the graphite spheroidizing disk 21. Later, due to the high-speed swirling effect, the material is thrown up and circulated from top to bottom in the spheroidizing chamber shell 1. The large second-mouth material in the classified fine and irregular fine-grained graphite is spheroidized into fine-grained spherical graphite through a single device, and the fine lamellar scales are kneaded into a ball to form an elliptical or quasi-spherical graphite, and the yield is above 70%, realizing the reuse of the second-mouth material (since the raw material of this equipment is fine and irregular fine-grained graphite, which is the tail powder obtained by crushing, spheroidizing and grading by multiple previous equipment, it can also be called second-mouth material). In addition, since the equipment is a single machine, the length of the entire production line is reduced, the cost investment is reduced, and the ball formation rate of fine-grained spherical graphite is improved.

[0106] (3) In the currently available graphite spheroidization technology, multiple spheroidization equipment are often used in series for joint processing. This equipment uses a single device for batch spheroidization, which greatly reduces the number of machines and reduces the cost of the spheroidization process.

[0107] The above are only exemplary embodiments of the present invention and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A fine-grained graphite batch spheroidizing device, characterized in that: including a shell having a spheroidized cavity; A rotatable grinding disc structure and a rotatable grading cage impeller are respectively provided at the bottom and the top of the spheroidizing cavity, wherein the grading cage impeller comprises a rotating shaft, a top frame and a bottom plate spaced apart from each other, and a flow dividing fence connected between the top frame and the bottom plate; the rotating shaft is fixedly connected to the bottom plate, and its lower end extends out of the bottom plate and is connected to an auxiliary blade assembly and a flow guide arranged in an upper and lower manner, wherein the auxiliary blade assembly comprises a plurality of auxiliary blades spaced apart from each other on the rotating shaft in a circumferential manner and can cause the airflow to form a vortex; An annular graded flow guide component is provided on the outer periphery of the graded cage impeller and close to the inner wall of the spheroidizing cavity. The graded flow guide component includes a plurality of flow guide blades arranged at intervals in the circumferential direction, and a plate surface of each of the flow guide blades is inclined relative to a corresponding radial direction in the spheroidizing cavity and the inclination direction is the same.

2. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: The guide blade is a rectangular plate body with a plate surface vertically arranged, and the inclination angle range of the plate surface of the guide blade relative to the corresponding radial direction in the spheroidizing cavity is 66-75°.

3. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: The diverter fence includes a plurality of diverter rods evenly spaced circumferentially, and the two ends of the diverter rods are respectively connected to the outer edge positions of the top frame and the bottom plate; the graded cage impeller is an inverted cone structure with an outer diameter gradually increasing from bottom to top.

4. The fine-grained graphite batch spheroidizing equipment according to claim 3, characterized in that: The rotation speed of the graded cage impeller is less than or equal to 3000 r / min.

5. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: The guide member is a teardrop-shaped structure with a rounded lower end and a gradually narrowed upper end.

6. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: The cross section of the shell is circular, and the inner wall of the shell includes a first cylindrical surface, a conical surface with a diameter increasing from bottom to top, and a second cylindrical surface connected in sequence from bottom to top. The grinding disc structure is arranged opposite to the first cylindrical surface, and the graded cage impeller is arranged opposite to the second cylindrical surface.

7. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: A feed pipe and a finished product discharge pipe can be connected in a disconnectable manner at a position on the side of the shell corresponding to the area between the grading cage impeller and the grinding disc structure; an air outlet is provided at a position on the top of the shell facing the grading cage impeller, and a tail powder discharge pipe can be connected in a disconnectable manner; a discharge valve is provided on the finished product discharge pipe, and the discharge valve can be automatically opened after a preset time of material spheroidization to complete the discharge; The tail powder discharging pipe is also connected with an induced draft fan, and the bottom of the shell is also provided with an air supply port which can be communicated with the spheroidizing cavity.

8. The fine-grained graphite batch spheroidizing equipment according to claim 7, characterized in that: The end of the feed pipe away from the shell is also connected to a hopper, the hopper is connected to the first end of the screw conveyor, the second end of the screw conveyor is connected to a silo, the lower part of the silo is a cone with an inner diameter that tapers downward, and an air disc is provided on the inner wall of the cone.

9. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: The grinding disc structure comprises at least two layers of graphite spheroidizing discs arranged at intervals in the upper and lower directions, and a plurality of grinding blocks are arranged at intervals in the circumferential direction on the top surface of the graphite spheroidizing disc; an annular gear ring is arranged on the inner wall of the spheroidizing cavity at a position facing the grinding disc structure.

10. The fine-grained graphite batch spheroidizing equipment according to claim 9, characterized in that: The cross section of the grinding block is a parallelogram, and a plurality of annular grooves are arranged on the outer side wall of the grinding block from top to bottom. Part of the grinding block extends out of the outer peripheral edge of the graphite spheroidizing disk and leaves a gap with the gear ring.

11. The fine-grained graphite batch spheroidizing equipment according to claim 1, characterized in that: An impeller driving device is also provided on the top of the shell, and the impeller driving device can be connected to the rotating shaft and used to drive the graded cage impeller to rotate; a grinding disc driving device is provided at the bottom of the shell, and the grinding disc driving device can be connected to the grinding disc structure and used to drive the grinding disc structure to rotate.

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