An assembled sagger structure

Abstract

The application discloses an assembled sagger structure, which comprises a sagger body, a sagger cover and accessories, wherein the sagger body is composed of separable upper and lower sagger bodies; the upper sagger body comprises a graphite shell and a partition plate, the graphite shell is in a columnar shape, air exchange holes are formed in the lateral wall of the graphite shell, and a heat buffer interlayer is formed between the partition plate and the graphite shell; the upper sagger body is closed by the sagger cover at the top surface and is integrated with the lower sagger body at the bottom surface; the lower sagger body is integrally formed by graphite, the top surface of the lower sagger body is matched with the bottom surface of the upper sagger body, and a bottom lining structure is arranged at the outer edge of the lower sagger body; the top surface of the bottom lining structure is provided with a lower concave splicing groove, which is matched with the staggered stepped structure of the heat buffer interlayer, so that the splicing can be conveniently positioned; and a plurality of through holes are formed in the annular surface of the bottom lining structure, which are used as high-temperature flue gas channels. The application can improve the heat efficiency and graphitization quality of carbon products during graphitization treatment in an Acheson graphitization furnace, is convenient to form and maintain, and can effectively reduce the production cost and resource consumption.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of auxiliary production equipment for carbon products, in particular to an assembled saggar structure suitable for Acheson graphitization furnace. BACKGROUND

[0002] Currently, there are mainly two types of graphitization furnaces on the market for refining lithium battery graphite negative materials: series-connected furnaces with internal heating design and Acheson graphitization furnaces with external heating design. Compared with series-connected furnaces with internal heating design, Acheson graphitization furnaces have been the preferred thermal equipment for carbon industry graphitization production enterprises for a long time due to their simple structure and convenient operation.

[0003] Considering that graphite materials have high temperature resistance, excellent thermal conductivity and excellent thermal shock resistance, the corresponding graphite crucibles or graphite saggars are ideal heating containers for Acheson graphitization furnaces. Among them, the crucible structure has limited loading capacity and poor heat preservation performance than the saggar, and is usually a one-time sintering tool, so it is mostly used for small batch sintering operations. In addition, the graphitization furnace is a high-energy consumption device, and the crucible is usually cylindrical. The space between them must be left to accommodate the circular shape, which results in the need to reserve more circular cutting space between adjacent crucibles. These spaces need to be filled with a large amount of resistance material during heat treatment, but this approach not only increases additional power consumption and reduces the thermal efficiency of the graphitization furnace, but also easily causes uneven temperature distribution in the furnace, thereby affecting the quality of graphitization. The saggar has excellent high temperature resistance, chemical corrosion resistance and thermal stability, and also has the advantages of large loading capacity, easy operation and reusability; it can also effectively reduce the amount of resistance material filling and unnecessary power consumption, and can adapt to large batch production operations. However, the traditional saggar structure has some problems in use, for example, since the saggar is usually made of a single material, its thermal expansion coefficient does not match other components inside the graphitization furnace, which easily generates thermal stress at high temperatures, causing the saggar to deform or even be damaged. In addition, the traditional saggar has the disadvantages of uneven temperature at the same cross section in the baking area and large temperature difference at different cross sections, which leads to low product quality or uneven performance of the sintered product, affecting the quality of graphitization.

[0004] In view of the above problems, the applicant proposed a saggar for carbon product baking in the previous application (the structure of the saggar is as shown in Figure 1The shown), aiming at solving these technical problems. However, the forming difficulty of the sagger in the actual production process is relatively large, especially the sagger body 2, as a carbon structure, the forming process of the sagger body 2 is usually based on the graphite sagger forming process commonly used in the industry, mainly including mechanical processing forming and integral compression forming two methods, the mechanical processing forming first manufactures a whole graphite blank, and then forms on the basis of the whole graphite blank through the mechanical processing method, but the disadvantage of this method is that the effective utilization rate of the graphite blank is low, a large amount of graphite chips and waste are generated, resulting in waste of resources. In addition, the heat buffer cavity 10 in the tapered bottom part of the sagger body 2 has great difficulty in processing, and has the problem of low yield. Although the integral compression forming process improves the utilization rate of the graphite blank and has low forming difficulty, it has the defects of huge equipment investment and complicated process, resulting in high production cost, and the blank after compression forming is easy to crack in the high-temperature sintering process, also has the problem of low yield.

[0005] Therefore, the present application provides a new assembled sagger structure, which aims to overcome the shortcomings of the prior art and improve the use performance and production efficiency of the sagger. SUMMARY

[0006] The technical problem solved by the present application is to provide an assembled sagger structure to solve the defects in the above technical background.

[0007] The technical problem solved by the present application is solved by the following technical scheme:

[0008] An assembled sagger structure, comprising a sagger body, a sagger cover and accessories, the sagger body is composed of an upper sagger body and a lower sagger body which can be separated;

[0009] The upper sagger body comprises a graphite shell and a partition plate, the graphite shell is a cylindrical shape with a circular or square ring cross-section, the graphite shell is formed by machining a whole graphite blank, and air exchange holes are uniformly machined on the side wall; the partition plate is concentrically arranged on the inner side of the graphite shell, and a heat buffer interlayer is separated between the partition plate and the graphite shell, and the heat buffer interlayer is filled with porous refractory material;

[0010] The heat buffer interlayer and the partition plate form a staggered step structure on the lower bottom surface of the upper sagger body, and the bottom surface plane of the partition plate is located above the bottom surface plane of the heat buffer interlayer;

[0011] The top surface and the bottom surface of the upper sagger body are both open surfaces, the top surface opening is closed by the sagger cover with matching size, and the bottom surface opening is closed by the combination and splicing of the lower sagger body;

[0012] The lower pot body is an integral graphite structure formed by integral mold pressing, which is a hollow cone with a large top and a small bottom; the top surface of the lower pot body matches the bottom surface of the upper pot body, and a bottom lining structure is formed on the outer edge of the top surface; the bottom surface of the bottom lining structure is attached to the inner wall of the cone and is formed as an integral part; the top surface of the bottom lining structure has a width greater than the sum of the thickness of the thermal buffer layer and the partition plate; a lower concave splicing groove is formed on the top surface of the bottom lining structure, which corresponds to the orthographic projection profile of the thermal buffer layer and the partition plate, and matches the thermal buffer layer and the partition plate lower surface staggered step structure to facilitate the alignment and splicing of the upper pot body and the lower pot body.

[0013] A plurality of through holes are uniformly formed on the annular surface of the bottom lining structure as high-temperature flue gas passages, which are arranged obliquely along the inclined surface of the cone of the lower pot body and communicate with the hollow cavity of the lower pot body and the bottom of the thermal buffer layer.

[0014] As a further limitation, the volume ratio of the upper pot body to the volume part of the lower pot body is controlled between 1:1 and 3:1 to ensure the thermal stability and strength of the overall structure of the sagger.

[0015] As a further limitation, the top surface of the partition plate is below the plane of the top surface of the upper pot body, and the sagger cover has a staggered cover step matching the top surface of the upper pot body; after the sagger cover is covered on the top surface of the upper pot body, a gap height of 1 / 10 to 1 / 8 of the height of the sintering space is left between the top surface of the partition plate and the bottom surface of the cover plate, and the minimum value of the gap height is 10 cm.

[0016] The thermal buffer layer is closed to the top surface plane of the partition plate at the top by using high thermal conductivity filler, which is one or a combination of aluminum silicate fiber, ceramic fiber, refractory brick, refractory mortar, and rock wool.

[0017] As a further limitation, the ventilation holes on the surface of the graphite shell are round holes, the hole diameter of the ventilation holes is 5-30 mm, and the hole diameter of the lower position ventilation hole is smaller than that of the upper position ventilation hole.

[0018] As a further limitation, the porosity of the porous refractory material is 30%-40%.

[0019] As a further limitation, the thickness ratio of the graphite shell to the thermal buffer layer in the upper pot body is between 1:1 and 1:3, and the thickness of the partition plate does not exceed half the thickness of the graphite shell.

[0020] As a further limitation, a matching protrusion and groove are formed on the bottom of the thermal buffer layer and the bottom surface of the lower concave splicing groove of the bottom lining structure. The combination of the protrusion and the groove is used for the alignment and splicing of the upper pot body and the lower pot body.

[0021] As a further limitation, the accessory includes a structural support for standing and holding the lower pot body, a placing plate for placing materials in the sagger, and a positioning pad placed on the placing plate for positioning the carbon product to be processed.

[0022] Beneficial effects: The assembled sagger structure of the present application adopts an assembled design, which effectively solves the problems of great forming difficulty, serious resource waste, and low yield rate in the overall production process of traditional sagger structures by adopting mechanical forming and overall molding to manufacture the graphite shell of the upper pot body and the body of the lower pot body. Thanks to the independent forming design of the upper pot body and the lower pot body, the production process is significantly simplified, the forming difficulty is reduced, the production cost is reduced, the efficiency is improved, and the maintenance and repair work also become more convenient.

[0023] The staggered stepped structure design of the upper pot body and the lower pot body ensures the stability of the assembled sagger during high-temperature sintering, effectively avoiding the generation and development of cracks.

[0024] The multi-combination layer structure of the upper pot body can not only effectively reduce thermal stress and reduce deformation and damage of the sagger at high temperature, but also improve the temperature uniformity inside the sagger, thereby improving the quality and performance consistency of the graphitization product.

[0025] By filling the thermal buffer interlayer with porous refractory material and optimizing the design of the air exchange hole and the high-temperature flue gas channel to control the escape and release of volatile gas components, the thermal stress can be effectively reduced, the thermal stability of the sagger can be enhanced, the good gas exchange capacity during sintering can be ensured, and the adverse effects of thermal stress on the sagger structure can be reduced, thereby improving the overall service life of the sagger. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic diagram of the sagger structure of the prior art.

[0027] Figure 2 It is a schematic diagram of the sagger structure of the preferred embodiment of the present application.

[0028] 1, sagger cover; 2, sagger body; 3, porous refractory filler; 4, air exchange hole; 5, partition; 6, roasting space; 7, positioning pad; 8, placing plate; 10, thermal buffer cavity; 11, refractory material block; 13, high thermal conductivity filler; 14, graphite shell; 15, bottom lining structure; 16, high-temperature flue gas channel; 17, lower pot body. DETAILED DESCRIPTION

[0029] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0030] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0031] Referring to Figure 2 A preferred embodiment of an assembled saggar structure in the present embodiment is a technical solution for Figure 1 The technical improvement of the present application is a further improvement of the invention patent: A saggar for carbon product baking (Patent No. ZL202011196337.6). The technical improvement makes the saggar with the corresponding conical bottom heat buffer cavity 10 structure easier to form, improves the yield and reduces the preparation cost, while meeting the demand of large-scale production. In addition, when this improved saggar is applied in an Acheson graphitization furnace, it can improve the temperature distribution inside the saggar, reduce the difference in graphitization quality caused by uneven temperature, ensure the uniformity of the graphitization process, and thus improve the quality of the graphitized products. In addition, this structure design also allows quick replacement or repair according to actual needs during the use of the saggar, significantly improving production efficiency and equipment reliability.

[0032] The assembled saggar structure includes a saggar body, a saggar cover 1 and accessories. In different embodiments, the cross section of the saggar body can be a circular ring or a square ring, which can be selected according to actual production needs.

[0033] In the present embodiment, the saggar body is composed of a separable upper saggar body and a lower saggar body 17, the upper saggar body includes a graphite shell 14 and a partition plate 5, the graphite shell 14 is a hollow cylindrical shape as a whole, and the cross section of the graphite shell 14 can be selected as a circular ring or a square ring according to the cross section shape of the saggar body; and the lower saggar body 17 is an integrated graphite structure manufactured by integral molding process.

[0034] The inner volume of the upper pot body is the roasting space 6, and the inner volume of the lower pot body 17 is the heat buffer cavity 10. Through experiments, when the volume ratio of the roasting space 6 to the heat buffer cavity 10 is controlled between 1:1 and 3:1, the heat stability and strength of the overall structure of the sagger are in a relatively optimal state, and when the volume ratio of the roasting space 6 to the heat buffer cavity 10 is controlled at 2.25:1, the overall structure of the sagger has the best heat stability and strength.

[0035] The graphite shell 14 is formed by machining in this embodiment. Specifically, a graphite blank with a size slightly larger than the graphite shell 14 is selected, the top surface is cut, the corresponding shell blank is cut out, and the air exchange holes 4 are uniformly machined on the side wall of the shell blank. In this embodiment, the air exchange holes 4 are replaced with circular holes with better machining performance and stability. The diameters of the air exchange holes 4 are 5-30 mm, and the diameters of the lower air exchange holes 4 are smaller than those of the upper air exchange holes 4. These air exchange holes 4 not only serve as air exchange channels to help the exchange of gases inside the sagger, but also promote the discharge of volatile gases during sintering, thereby reducing the internal pressure and preventing the sagger from being damaged due to excessive internal pressure. The graphite shell blank with air exchange holes 4 is further finely machined using a machining device to ensure the dimensional accuracy and surface finish of the graphite shell 14.

[0036] The intermediate block cut out during the top surface cutting process is equivalent to peeling off only one layer of skin after the shell blank is cut out, and still has a relatively complete size. Therefore, the remaining material still has good secondary machining performance and can be used to machine smaller graphite shells 14 or other graphite products. Compared with other types of leftover materials with irregular shapes, the material utilization rate is higher.

[0037] The partition plate 5 is concentrically arranged inside the graphite shell 14 to separate a sandwich space between the partition plate 5 and the graphite shell 14 as a heat buffer sandwich. In order to realize the heat buffer function, the heat buffer sandwich is uniformly filled with porous refractory filler material 3 with a porosity of 30%-40%. The porous refractory filler material 3 can be formed by using the high-temperature resistant filler material with good high-temperature resistance performance in the prior art.

[0038] In this embodiment, the thickness ratio of the graphite shell 14 in the upper pot body to the thermal buffer interlayer should be kept within the range of 1:1 to 1:3, and the thickness of the partition plate 5 should not exceed half the thickness of the graphite shell 14. Such a thickness design ensures that the effect of the thermal buffer interlayer in absorbing and dispersing heat by using the porous refractory filler 3 filled therein is optimal, while maintaining the stability of the overall structure of the upper pot body, which not only ensures that the pot has sufficient mechanical strength in the face of high-temperature environments and chemical corrosion, but also guarantees its own good physical structural stability.

[0039] At the top position in the upper pot body, the top surface plane of the partition plate 5 is designed to be lower than the top surface plane of the graphite shell 14, forming a staggered step surface. Correspondingly, the outer edge of the pot cover 1 is also equipped with a staggered cover closing step that matches the top surface of the graphite shell 14. When the pot cover 1 is tightly closed with the top surface of the upper pot body, a height difference gap will be formed between the top surface of the partition plate 5 and the bottom surface of the pot cover 1. This gap is set to be 1 / 10 to 1 / 8 of the height of the roasting space, and the minimum height should not be less than 10 cm. Such a structural design plays a key role in the graphitization process, allowing auxiliary pressure relief through the height difference gap at the upper part of the partition plate 5. This design effectively prevents the gas pressure from being too high when there is too much volatile matter, thereby avoiding the situation where the pot cover 1 is blown off by the gas pressure, and also preventing the carbon material to be heat treated or the partition plate 5 from being plastically deformed due to excessive internal gas pressure.

[0040] In actual application, considering that the refractory lining block 11 may be deformed due to the combined action of volatile matter and thermal stress, the refractory lining block 11 must have a certain thermal expansion coefficient. In addition, as shown in Figure 1 The top surface of the refractory lining block 11 can be filled and closed with high thermal conductivity fillers 13 corresponding to the position of the partition plate 5. These high thermal conductivity fillers 13 can be one or a combination of aluminum silicate fiber, ceramic fiber, refractory brick, refractory mortar, and rock wool, closed below the top surface plane of the partition plate 5 to adapt to the temperature fluctuations in the graphitization furnace and reduce the impact of thermal stress on the stability of the overall structure of the upper pot body.

[0041] At the bottom position in the upper pot body, the lower bottom surface of the porous refractory filler 3 in the thermal buffer interlayer and the lower bottom surface of the partition plate 5 form a staggered step structure with the lower bottom surface of the partition plate 5 being lower than the lower bottom surface of the porous refractory filler 3.

[0042] As shown in Figure 1The lower pot body 17 in the embodiment is shown as a hollow inverted cone structure with a top wider than the bottom, and the overall molding process adopted ensures the integrity and strength of the conical structure. The top of the lower pot body 17 is designed with a connecting structure that fits the bottom of the upper pot body. Specifically, the top of the lower pot body 17 fits the bottom of the upper pot body, and a ring of bottom lining structure 15 is formed at the edge of the top of the lower pot body 17. The bottom of the bottom lining structure 15 is in close contact with and integrated with the conical inner wall, and the top width exceeds the total thickness of the thermal buffer layer and the partition plate 5. On the top surface of the bottom lining structure 15, a concave splicing groove is designed, which is adapted to the staggered stepped structure of the porous refractory filler 3 and the partition plate 5, so that the lower pot body 17 can be precisely spliced with the bottom of the upper pot body Figure 1 The precise butt joint splicing is shown.

[0043] In another embodiment, to further improve the matching performance of the upper pot body and the lower pot body 17, matching protrusions and grooves can be formed on the bottom of the porous refractory filler in the thermal buffer layer and the bottom surface of the lower concave splicing groove of the bottom lining structure 15. The combination of these protrusions and grooves can further optimize the precise butt joint splicing of the upper pot body and the lower pot body 17, ensure that the assembled pot structure remains stable due to the thermal expansion and contraction principle of the structure during high-temperature sintering, and ensure that the pot does not shift or deform during high-temperature sintering. It can also help improve the sealing performance of the splicing position.

[0044] The annular surface of the bottom lining structure 15 is uniformly distributed with a plurality of through holes as high-temperature flue gas passages 16, which are arranged obliquely along the conical slope of the lower pot body 17 and are respectively connected to the thermal buffer cavity 10 of the lower pot body 17 and the bottom of the thermal buffer layer at both ends. The design of the high-temperature flue gas passages 16 enables the high-temperature flue gas generated inside the pot to flow smoothly, thereby improving the heat exchange efficiency. These high-temperature flue gas passages 16 not only help to discharge flue gas, but also to some extent adjust the temperature distribution inside the pot, ensuring the uniformity of the sintering process. In addition, the oblique configuration of the high-temperature flue gas passages 16 significantly reduces the direct impact of flue gas flow on the pot structure, effectively solving the problems of mechanical strength reduction and easy deformation and damage caused by the hole-making or split detachable structure of the traditional split pot, which not only improves the actual reuse rate of the pot, but also significantly prolongs its service life.

[0045] In this embodiment, the use of the pot first requires positioning through the bottom lining structure 15 at the center of the lower pot body 17, and then placing and fixing the placement plate 8; then, the positioning pad 7 for placing the carbon products to be processed is arranged at the center of the placement plate 8, and then the upper pot body is spliced with the lower pot body 17 as Figure 1The shown patterns are spliced together, and after splicing, the bottom surface is supported and fixed in position using refractory blocks 11, ensuring the stability and levelness of the sagger body 2 when placed on the trolley. At this time, the upper part of the placement plate 8 and the inner side of the partition plate 5 form a baking space, and the evenly distributed air holes on the placement plate 8 are in communication with the heat buffer cavity 10.

[0046] During the execution of the graphitization process, only the carbon products to be treated need to be fixed on the positioning pad 7. The heat buffer cavity 10 can form a thermal stress buffer zone during the baking process, allowing the temperature difference section to move down into the heat buffer cavity 10. Through the large top and small bottom conical structure of the heat buffer cavity 10, the temperature difference fluctuation in the baking space can be effectively reduced. During the execution of the graphitization process, the combination of the sandwich structure and the porous refractory filler material 3 can form a heat preservation layer on the outside of the baking space. In addition, the porous refractory filler material 3 with a specific porosity can form an exhaust and pressure relief path with the high-temperature flue gas channel 16 and the air exchange hole 4, allowing excess volatile substances generated during the baking process to be discharged from the air exchange hole 4 through the gaps in the porous refractory filler material 3 without affecting the temperature of the baking space.

[0047] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. An assembled saggar structure, characterized by, The invention relates to a graphite saggar, which comprises a saggar body, a saggar cover and an accessory. The upper saggar body comprises a graphite shell and a partition plate, the graphite shell is a cylinder with a circular or square cross section, the graphite shell is formed by machining a whole graphite blank, and air exchange holes are uniformly machined on the sidewall of the graphite shell; the partition plate is concentrically arranged on the inner side of the graphite shell, a thermal buffer layer is formed between the partition plate and the graphite shell, and a porous refractory material is filled in the thermal buffer layer; The thermal buffer layer and the partition plate form a staggered step structure on the lower bottom surface of the upper saggar body, and the bottom surface of the partition plate is located above the bottom surface of the thermal buffer layer; The top surface and the bottom surface of the upper saggar body are both open surfaces, the top surface is closed by the saggar cover, and the bottom surface is closed by the combination of the lower saggar body. The lower saggar body is an integrated graphite structure formed by integral mold pressing, and has a shape of a hollow cone with a large upper part and a small lower part; the top surface of the lower saggar body is matched with the bottom surface of the upper saggar body, and a bottom lining structure is formed on the outer edge of the top surface, the bottom surface of the bottom lining structure is attached to the inner wall of the cone and formed as a whole, and the top surface of the bottom lining structure has a width greater than the sum of the thicknesses of the thermal buffer layer and the partition plate; a lower recessed splicing groove is formed on the top surface of the bottom lining structure, the lower recessed splicing groove is formed at the position corresponding to the orthographic projection of the thermal buffer layer and the partition plate, and is matched with the staggered step structure of the lower surfaces of the thermal buffer layer and the partition plate, so as to facilitate the alignment and splicing of the upper saggar body and the lower saggar body; A plurality of through holes are uniformly formed on the annular surface of the bottom lining structure as high-temperature flue gas passages, the through holes are arranged obliquely along the inclined surface of the cone of the lower saggar body, and are connected with the hollow cavity of the lower saggar body and the bottom of the thermal buffer layer; The top surface of the partition plate is located below the plane of the top surface of the upper saggar body, the saggar cover has a staggered cover closing step matched with the top surface of the upper saggar body; after the saggar cover is closed on the top surface of the upper saggar body, a gap height of 1 / 10~1 / 8 of the height of the firing space is left between the top surface of the partition plate and the bottom surface of the saggar cover, and the minimum value of the gap height is 10 cm; The air exchange holes formed on the surface of the graphite shell are circular holes, the diameters of the air exchange holes are 5~30 mm, and the diameters of the air exchange holes formed on the lower part of the surface of the graphite shell are smaller than the diameters of the air exchange holes formed on the upper part of the surface of the graphite shell; A matching protrusion and groove are formed on the bottom of the thermal buffer layer and the bottom surface of the lower recessed splicing groove of the bottom lining structure, and the combination of the protrusion and the groove is used for the alignment and splicing of the upper saggar body and the lower saggar body.

2. The assembled saggar structure of claim 1, wherein, The volume ratio of the volume of the upper saggar body to the volume of the volume part of the lower saggar body is controlled to be between 1:1 and 3:

1.

3. The assembled saggar structure of claim 1, wherein, The top part of the thermal buffer layer is closed below the top surface of the partition plate by using high-thermal-conductivity fillers, the high-thermal-conductivity fillers are one or a combination of aluminum silicate fiber, ceramic fiber, refractory brick, refractory mortar and rock wool.

4. The assembled saggar structure of claim 1, wherein, The porosity of the porous refractory material is 30%~40%.

5. The assembled saggar structure of claim 1, wherein, The thickness ratio of the graphite shell to the thermal buffer layer in the upper saggar body is between 1:1 and 1:3, and the thickness of the partition plate does not exceed half of the thickness of the graphite shell.

6. The assembled saggar structure of claim 1, wherein, The accessory comprises a structural support for the upright positioning and retention of the crucible, a setting plate for the positioning of the material inside the crucible and a positioning mat placed on the setting plate for the positioning of the carbon product to be treated.

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