JP5980006B2 - Container used for firing graphite material, firing container, and firing method - Google Patents

Description

  The present invention relates to a vessel used for firing a graphite material, a firing container, and a method for firing a graphite material using the same.

The graphite material is manufactured according to the following process.
(1) Primary crushing step for obtaining a raw material coke pulverized raw material (2) Kneading step for obtaining a kneaded product of pitch and raw material coke (3) Secondary pulverizing step for pulverizing the kneaded material to obtain a forming raw material (4) Molding step of forming a molded body (5) Graphite that heats the molded body to remove volatile matter and obtain a fired body (6) Heat treatment of the fired body at a temperature higher than that of the firing step to graphitize The baking step (5) carbonizes the binder while slowly removing volatile components from the binder such as pitch. The binder is carbonized and becomes part of the graphite material. In order to prevent oxidation of the binder and the pulverized raw material, the compact is fired by using a filling powder (packing material) or in a fired can (fired box, fired container).

In Patent Document 1, when a molded body of a carbon material is fired in a firing furnace, the inside of the firing furnace is maintained in a non-oxidizing atmosphere without filling the periphery of the molded body, and the temperature rises at 10 ° C. or more per hour. A method for producing a carbon material is disclosed in which the compact is heated and fired at a speed.
In Patent Document 2, a plurality of inner boxes with lids containing powder compacts are stacked, and a decomposition gas equivalent to or similar to the powder compact is generated by firing in the outer upper or uppermost inner box of the inner box. A method for firing a powder compact is disclosed, in which a substance to be placed is placed, loaded into an outer box, covered, packed in a firing furnace, and fired in a non-oxidizing atmosphere.

JP-A-60-54909 JP-A-4-238771

In the firing process of the graphite material, it is treated at a high temperature in order to remove volatile components and carbonize the binder. As described in Patent Documents 1 and 2, conventionally, a firing container has been used to prevent oxidation of a graphite material molded body.
The firing container described in Patent Document 1 or 2 has a structure in which a vessel for containing contents is covered and fired. In such a baking container with a structure simply having a lid on the body, when used in a baking furnace, an oxidizing gas such as air enters from the outside, and the graphite material inside the baking container is easily oxidized. Become. In particular, as the size of the molded body is increased, the heating rate of the baking is reduced and the number of days required for the baking is also increased. When the number of days for firing becomes longer, the oxidizing gas is more likely to enter.
An object of the present invention is to provide a vessel, a firing container, and a firing method for preventing oxidation of a fired product using the same.

The present invention is an instrument body having an opening in the upward direction and used for firing a graphite material by placing a lid on the opening,
The container has a groove for supporting the lid along the outer periphery or inner periphery of the opening. The present invention preferably has the following aspects.
1a) The groove has a width of 10 to 100 mm.
2a) The groove has a depth of 10 to 150 mm.
3a) The container is made of metal.
4a) The metal is stainless steel.
5a) The vessel is a rectangular parallelepiped.
6a) It has the reinforcement part which is formed in a grid | lattice form and consists of a rib in the outer surface of the said container.
Moreover, this invention is a baking container characterized by including the said container and the lid | cover which has a frame part further fitted in the said groove | channel.
Furthermore, the present invention places a molded body of graphite material in the vessel body, closes the lid frame so as to sink the frame portion of the lid, and fills the groove with a powdery or granular filler material, There is provided a method for producing a graphite material, characterized by firing the molded body.
The present invention preferably has the following aspects.
1b) The filler filled in the groove is further covered with a coating material made of an inorganic paste.
2b) The covering material is mortar.
3b) The graphite material molded body in the firing container is sunk into a filling powder and fired.
4b) A gas generator that generates a non-oxidizing gas by heating is provided in the baking container.
5b) The gas generator is an organic substance.

  According to the present invention, it is possible to provide a structure and method in which the outside air of the firing container does not easily enter the container, so that the graphite material (molded body) in the firing container can be hardly oxidized. In the present invention, the graphite material can be fired by a simple means without requiring a low-oxygen atmosphere furnace, so that the equipment for the firing process can be simplified.

(A) It is a schematic diagram explaining the baking container of embodiment of this invention. The figure shows a cross section by a vertical surface, but the line shows a cross section of a plate having a predetermined thickness. (B) is a schematic diagram which shows an example of the use condition of the baking container of (a). It is a schematic diagram explaining the baking container of embodiment of this invention, and is the perspective view drawn using the same line as FIG. It is a schematic diagram explaining the baking container of embodiment of this invention, and is the perspective view drawn using the same line as FIG. It is a perspective view of the baking container of other embodiment of this invention.

In this invention, a baking container consists of a container and a lid | cover, a container shows the member which accommodates the molded object of a graphite material, and a cover shows the member which covers and uses the said container. The firing container integrally using the container body and the lid of the present invention functions to prevent intrusion of outside air (oxidizing gas) and to prevent oxidation of the formed graphite material as the content.
The container of the present invention has an opening in the upward direction, and is a container used for firing a graphite material by placing a lid on the opening, and the container is along the outer periphery or inner periphery of the opening, A groove for supporting the lid; This vessel has a graphite material accommodating portion, and forms a closed space by closing the opening with a lid. The accommodating portion is formed of a side wall and a bottom portion, and the groove is provided on the side wall along the outer periphery or inner periphery of the upper opening. The groove has a groove bottom portion having a predetermined width and a groove side portion having a predetermined depth. The region including at least the groove bottom portion extending outwardly in the side wall direction of the housing portion is coupled to the side wall of the housing portion, and the side wall can bear all or part of one side of the groove side portion. The side wall of the housing part that is coupled to the side wall to form a groove may be inside, outside, or both of the housing part.

The groove used in the present invention has a function of holding a powdery or granular filler and a function of closing an opening by holding a lid. In the specification of the present application, “powdered” means that the average equivalent circle diameter is less than 0.1 mm, and “granular” means that the average equivalent circle diameter is 0.1 to 20 mm.
The average equivalent circle diameter indicates the projected area equivalent circle diameter, and indicates the diameter of a circle having the same area as the projected area of the particles.
The groove used in the present invention sinks the frame portion of the lid at the time of firing, and can hold a powdery or granular filler in all or at least a part thereof. Since the filler filled in the grooves in this way can slow the gas diffusion rate, it can make it difficult for the oxidizing gas outside the firing vessel to enter. Moreover, since the internal pressure of the firing can can be increased by using a gas generator that generates a non-oxidizing gas by heating inside the firing container, it is possible to further prevent the invasion of the oxidizing gas. it can.
Hereinafter, it will be described that the temperature raising process of firing is more sensitive to oxidation than the temperature lowering process, and the gas generator works effectively.
The graphite material has a low strength at the molded body stage before firing, low thermal conductivity, and large shrinkage during firing in the heating process, so the temperature is increased slowly. The fired graphite material after reaching the maximum temperature has high strength and thermal conductivity, and the amount of heat shrinkage during the cooling process is small, so that it can be quickly cooled. In addition, the binder exists as an organic substance that is easily combined with oxygen in the temperature rising process, and the binder is carbonized in the cooling process after firing, and the reactivity with oxygen is reduced. That is, it is important to prevent oxidation of the graphite material particularly during the temperature rising process, by comparing the reactivity between the temperature rising process and the cooling process and the time required for the temperature rising or cooling. Since the gas generator increases the internal pressure of the firing container during the temperature rising process, it effectively functions to prevent oxidation of the graphite material.

  In the present invention, the graphite material is placed in the housing portion of the container, and the lid is covered and baked. However, by closing the frame portion of the lid in this groove, the closure of the lid can be improved, and the above oxidizing property The effect of preventing gas intrusion can be exhibited.

In the present invention, the space shape of the groove and the shape of the material constituting the groove are basically arbitrary as long as the above functions can be exhibited.
The groove has a width and a depth. As described above, the width and depth are determined by the structure and material thickness of the groove bottom and groove side portions. The width and depth are not particularly limited as long as the structure of the groove is not adversely affected even if the firing container is deformed by repeated temperature changes, but each is usually a constant width or depth. It is preferable from the viewpoints of handleability, designability, cost and the like. The width is an inner distance between the groove side portions, and the depth is a distance from the inner surface of the bottom portion to the groove opening.
The width is preferably 10 to 100 mm. If it is less than 10 mm, the lid tends to be hard to fit even if the lid is slightly thermally deformed, and the container may not be used for a long time. If it exceeds 100 mm, the outer dimensions of the vessel will increase, and the packing efficiency into the firing furnace will deteriorate.
The depth is preferably 10 to 150 mm. If it is less than 10 mm, the amount of the filler spilled due to oxidation or movement will decrease, and the outside air tends to easily enter the firing container. When it exceeds 150 mm, the effectiveness of the outside air blocking property of the filler becomes constant, and the packing powder is wasted. If it exceeds 150 mm, it will be difficult to remove foreign matter when it falls into the groove, and if the lid is placed with the foreign matter remaining, the lid will not be completely closed and the outside air blocking property will deteriorate.

In addition, the constituent material and overall shape of the firing container (container, lid) of the present invention are basic as long as the groove can be formed and the heat resistance and mechanical strength capable of firing the graphite material are ensured. Arbitrarily.
As said constituent material, metal is preferable.
The graphite material is increased in size, and the firing container is required to be larger than that.
The metal can be integrally formed by welding or the like, and the strength of the seam portion such as a welded portion is high, so that a high outside air blocking property and a high strength firing container can be obtained at the same time.
In addition, the baking container is repeatedly subjected to thermal strain by heating and cooling. If the firing container is made of metal, the metal can be easily elastically deformed and plastically deformed, so that it can be made difficult to break.
Examples of the metal include iron, tungsten, platinum, copper and a copper alloy, aluminum and an aluminum alloy, stainless steel, and the like, and stainless steel is particularly preferable. SUS304, SUS316, etc. can be used as the stainless steel. Since stainless steel forms an oxide film, the progress of surface oxidation can be slowed even when used in an oxidizing atmosphere such as a combustion furnace, and the life of the vessel can be extended.
Moreover, although the thickness of a constituent material is fundamentally arbitrary, when it is metal, 3-15 mm is preferable normally. When it is 3 mm or more, a high-strength vessel is obtained, and when it is 15 mm or less, the weight of the entire vessel can be reduced.

  The overall shape of the firing container or vessel of the present invention is arbitrary as described above, and is not particularly limited as long as it does not adversely affect the structure of the housing portion by repeated firing, but is usually a simple three-dimensional A structure is preferable from the viewpoints of handling, design, cost, and the like. Examples of the three-dimensional structure include prisms such as prisms and cylinders, and a rectangular parallelepiped is preferable because a plurality of graphite materials can be packed efficiently.

  Moreover, it is preferable to have the reinforcement part which is formed in a grid | lattice form and consists of a rib in the outer surface of the container of this invention. The rib is formed by welding a metal flat bar having a width of about 30 to 80 mm so as to be substantially perpendicular to the outer surface. The size of the lattice is not particularly limited, but for example, one side is 50 to 300 mm. Although there is no restriction | limiting in particular in the structure of a reinforcement part, It couple | bonds by welding etc. so that it may become the said shape on the said outer surface by metal plate materials etc. During firing, the inside of the firing container is exposed to a reducing atmosphere, and an oxidizing atmosphere is allowed outside. Repeated use tends to carburize the inner surface and oxidize the outer surface. For this reason, warpage is likely to occur because a difference in thermal expansion occurs. If there is a reinforcing part, even if warpage occurs, it is only deformed in one lattice, and therefore, there is an effect that deformation to the whole baking container hardly occurs. Since warpage is likely to occur in a plane portion, it is particularly effective in a rectangular parallelepiped vessel whose side wall is a plane.

It is preferable that the firing container of the present invention includes a container and a lid having a frame portion that fits into the groove.
The structure and shape of the lid are basically arbitrary as long as it has a frame portion having a function of covering the opening of the vessel. The frame portion can be dropped into the groove.
For example, the frame portion may be provided continuously around the top plate of the lid so that the extension of the flat plate material is bent in the vertical direction, or is provided in the inner region of the top plate of the lid by welding or the like. It may be.
The frame portion is usually provided so as to be positioned in the groove, but may be used alone or in combination so as to be positioned in a groove side portion 2b1, a groove side portion 2b2, and the like described later.
The fitting relationship between the frame part and the groove including the time of firing is not particularly limited as long as the function of basically covering the opening is exhibited. The fitting relationship between the frame portion and the groove is preferably designed so that there is play. Further, the end portion of the frame portion may or may not be in contact with the surface of the groove bottom portion. In this case, the frame portion and the end portion of the side wall may or may not be in contact with each other, but it is preferable that they are not in contact with each other. If it is not in contact, the firing container will not easily close even if it is thermally deformed if it is repeatedly used.

  In the present invention, the graphite material is not particularly limited as long as it usually includes a molded body formed from a carbon material and the fired product of the molded body can be graphitized. The firing container of the present invention is suitable for firing a graphite material, but is not particularly limited to a graphite material as long as it can be used for this firing container, and can be used for firing any material.

  In the method for producing a graphite material according to the present invention, a graphite material molded body is placed in the container, and the lid is closed so that the frame of the lid is submerged in the groove of the container, and the groove is filled with powder or particles. Filling the material and firing the shaped body.

In the method for producing a graphite material of the present invention, the firing container is composed of a vessel body and a lid, and the vessel body indicates a member that accommodates a molded body of the graphite material, and the lid is used by covering the vessel body. The member to perform is shown. The firing container integrally using the container body and the lid of the present invention functions to prevent intrusion of outside air (oxidizing gas) and to prevent oxidation of the formed graphite material as the content.
The container of the manufacturing method of the present invention has an opening in the upward direction and is used for firing graphite material by placing a lid on the opening, and the container is on the outer periphery or inner periphery of the opening. Along the groove is a groove that supports the lid. This vessel has a graphite material accommodating portion, and forms a closed space by closing the opening with a lid. The accommodating portion is formed of a side wall and a bottom portion, and the groove is provided on the side wall along the outer periphery or inner periphery of the upper opening. The groove has a groove bottom portion having a predetermined width and a groove side portion having a predetermined depth. The region including at least the groove bottom portion extending outwardly in the side wall direction of the housing portion is coupled to the side wall of the housing portion, and the side wall can bear all or part of one side of the groove side portion. The side wall of the housing part that is coupled to the side wall to form a groove may be inside, outside, or both of the housing part.

The groove | channel of the container used for the manufacturing method of this invention has the function to hold | maintain a powdery or granular filler, and the function to close opening by hold | maintaining a lid | cover.
In the production method of the present invention, the groove of the container is covered with a lid, and all or at least a part of the groove is filled with a powdery or granular filler. Such a filler can slow the gas diffusion rate, and therefore can make it difficult for the oxidizing gas outside the firing vessel to enter.
Any powdery or granular filler in the production method of the present invention can be used. Coke pulverized into powder or granule, various ceramics pulverized into powder or granule, etc. can be used. Sand or gravel may be used.

In the production method of the present invention, it is desirable to further cover the filler with a coating material made of an inorganic paste.
In addition, there is no limitation on the method of applying the covering material to the filler, but specifically, the frame portion provided on the lid is closed by fitting it into the groove of the container, and then the filler is placed in the groove. Is placed so that the end of the frame is hidden, and the filler is covered with a covering material. Alternatively, after filling the groove with a filler and closing the lid, if necessary, the filler is further put into a gap between the groove and the frame of the lid, and then covered with a covering material.
By covering with the covering material, the filler can be prevented from being scattered by the airflow circulating in the firing furnace. Further, when a combustible material such as coke is used as the filler, it is possible to prevent direct contact with the outside air of the firing container, so that the oxidation consumption of the coke can be reduced. Although there is no restriction | limiting in particular in a coating | covering material, For example, what contains mortar or powders, such as silica, an alumina, a zirconia, silicon carbide, inorganic binders, such as aluminum phosphate, and liquids, such as water and ethanol, can be illustrated.

  Of these, it is desirable to use mortar. Since mortar is easily available and solidifies after firing, it is highly effective in preventing the filler from being oxidized or scattered. Further, since the mortar is solidified after firing, it can be easily separated by sieving, and the filler can be easily reused.

In the production method of the present invention, it is desirable to sinter the compact of the graphite material in the firing container into the filling powder. By submerging the graphite material compact in the packing powder, it is difficult for the oxidizing gas outside the firing container to enter the firing container and reach the graphite material compact, making the graphite material difficult to oxidize. it can.
The filling powder may be the same as or different from the filling material filling the groove of the container. It is more preferable that the combination of the filler and the filling powder is the same so that there is no problem even if they are mixed at the time of recovery. As the filling powder, as with the filler, coke pulverized into a powder or granule, various ceramics pulverized into a powder or granule, and the like can be used. Sand, gravel, etc. can be used.

The production method of the present invention preferably includes a gas generator that generates a non-oxidizing gas by heating in a baking container.
In the production method of the present invention, it is preferable that oxygen is as little as possible in the container during firing. Therefore, it is preferable that the container is replaced with a non-oxidizing gas, for example, a gas molecule other than oxygen during firing. As the non-oxidizing gas, a reducing gas such as hydrogen, carbon monoxide or hydrocarbon, or an inert gas such as nitrogen or argon can be used. These non-oxidizing gas atmospheres can be obtained by providing a gas generator that generates a non-oxidizing gas by heating in a firing container. Examples of such a gas generator include raw coke, hard pitch, coal such as tar, petroleum-related products, natural fibers such as paper, wood, and pulp, and various synthetic resins. These gas generators generate hydrogen, carbon monoxide, carbon dioxide, hydrocarbon gas, and the like by heating.
In addition, sodium hydrogen carbonate, calcium carbonate, and the like that generate carbon dioxide by heating can be used. Moreover, sodium azide etc. which generate | occur | produce nitrogen gas by heating can also be utilized.
Among them, it is preferable to use coal or petroleum related products such as raw coke, hard pitch and tar, natural fibers such as paper, wood and pulp, and organic substances such as various synthetic resins as the gas generator. These organic substances are preferable because the residue is carbonaceous and does not corrode the baking container. Among them, especially coal or petroleum-related products such as raw coke, hard pitch, and tar are a mixture of many substances, so that the temperature range for thermal decomposition is wide and can be suitably used as a gas generator.

In the manufacturing method of the present invention, since the firing container is closed by the groove and the lid of the container, the inside of the firing container is protected against the outside air by the non-oxidizing gas generated from the graphite material and the gas generator during firing. It becomes a positive pressure and effectively prevents the oxidizing gas such as the atmosphere from diffusing into the firing container.
As described above, the temperature raising process of firing is more sensitive to oxidation than the temperature lowering process, and the gas generator works effectively as described above, but this is repeated here.
The graphite material has a low strength at the molded body stage before firing, low thermal conductivity, and large shrinkage during firing in the heating process, so the temperature is increased slowly. The fired graphite material after reaching the maximum temperature has high strength and thermal conductivity, and the amount of heat shrinkage during the cooling process is small, so that it can be quickly cooled. In addition, the binder exists as an organic substance that is easily combined with oxygen in the temperature rising process, and the binder is carbonized in the cooling process after firing, and the reactivity with oxygen is reduced. In particular, it is important to prevent oxidation of the graphite material during the temperature rising process from the comparison of the reactivity between the temperature rising process and the cooling process and the time required for the temperature rising or cooling. Since the gas generator increases the internal pressure of the firing container during the temperature rising process, it effectively functions to prevent oxidation of the graphite material.

In the production method of the present invention, it is most important to use the firing container (container and lid) of the present invention for firing a graphite material. From the temperature in the firing furnace during firing and the firing container, the graphite material, etc. The gas composition such as oxygen concentration, the gas composition such as oxygen concentration, each gas partial pressure and the like are basically arbitrary, and can be appropriately set in consideration of the composition of the graphite material, the quality of the desired fired product, and the like.
The firing furnace is not particularly limited as long as it has a space in which the firing container can be taken in and out, and heating means, and those equipped with control means for temperature, gas pressure, etc., if desired. Can be mentioned.

The firing container is sealed by covering at the time of firing, but the structure of the lid and the mode of sealing are not particularly limited as described above.
Furthermore, after filling the groove with a filler, covering the filler with a covering material further suppresses the diffusion of the oxidizing gas into the accommodating portion, and can effectively maintain the non-oxidizing atmosphere in the accommodating portion. . The covering with the covering material may be the whole or a part of the boundary region with the outside air of the exposed filling powder.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to these embodiments.
In FIG. 1 (a), the firing container 1 of the present invention comprises a container 1a and a lid 10. The container 1a has a groove 2 and is formed of a metal plate having a desired thickness, which includes a housing part 3, a bottom part 4, a side wall 5, and an opening 6. The lid 10 includes a top plate portion 10a and a frame portion 10b.
The groove 2 includes a groove bottom portion 2a and groove side portions 2b1 and 2b2, and has a groove opening 2c. The groove side part 2b2 is formed as a part of the side wall 5 by joining the end part of the groove bottom part 2a of the L-shaped plate member to the side wall 5 by welding. The opening 6 is covered with the top plate portion 10 a and the frame portion 10 b is fitted into the groove 2.
FIG. 1 (b) shows the graphite material 11, the packing powder 12, the filler 13, and the covering material 14 when the graphite material 11 is placed in a firing device and fired using the firing container 1. The cross section of the aspect of arrangement | positioning is shown typically. As shown in the figure, the graphite material 11 is embedded in the filling powder 12, and when the lid 10 is put and the filler 13 is put into the groove 2, the groove opening 2c formed by the frame portion 10b and the groove side portion 2b1. Of these, the region 2 c 1 where the filler 13 is exposed may be blocked by the covering material 14. The covering material 14 may be applied to the groove side portion 2b1 and the top plate portion 10a.

  The shape of the firing container 1 shown in FIG. 1A is basically arbitrary as described above, and includes the rectangular parallelepiped shape of FIG. 2 and the cylindrical shape of FIG.

  The firing container 1 of FIG. 4 has a lattice-shaped reinforcing portion 7 on the surface of the bottom portion 4 and the side wall 5. The hanging tool 8 is used when the firing container 1 is moved.

  Examples of the present invention will be described below, but it is clear that the present invention is not limited thereto.

[Example 1]
The manufacturing method of the graphite material of this invention is demonstrated according to the following order.
(1) Primary crushing step for obtaining a raw material coke pulverized raw material (2) Kneading step for obtaining a kneaded product of pitch and raw material coke (3) Secondary pulverizing step for pulverizing the kneaded material to obtain a forming raw material (4) Molding step of forming a molded body (5) Graphite that heats the molded body to remove volatile matter and obtain a fired body (6) Heat treatment of the fired body at a temperature higher than that of the firing step to graphitize Process <Primary grinding process>
In the primary pulverization step, the aggregate of the graphite material is adjusted. As the aggregate, calcined pitch coke is used. The calcined pitch coke is pulverized by a roller mill so that the average particle diameter is about 15 μm to obtain a pulverized raw material. In addition, the kind of coke which is an aggregate, and an average particle diameter are not specifically limited, What kind of thing can be utilized.
<Kneading process>
The pulverized raw material obtained in the primary pulverization step is mixed with pitch and kneaded with a kneader while applying heat at 250 ° C. to obtain a kneaded product. The mixing ratio is 60 parts by weight with respect to 100 parts by weight of the pulverized raw material. The kneading temperature and pitch input amount are not particularly limited, and any conditions can be used.
<Secondary grinding process>
The kneaded product obtained in the kneading step is pulverized with a pin mill to obtain a forming raw material. The molding raw material has an average particle size of about 30 μm. The average particle size is not particularly limited, and any average particle size can be used.
<Molding process>
The molding raw material obtained in the secondary pulverization step is packed in a rubber bag and cold isostatic pressing (CIP: Cold Isostatic Press) to obtain a molded body. The molding pressure is 100 MPa. The size of the molded body is 400 × 600 × 1000 mm. The molding pressure is not particularly limited, and any apparatus and pressure such as extrusion molding and uniaxial molding can be used.

<Baking process>
The graphite material compact obtained in the above step is fired. First, prepare the body. The container has a shape as shown in FIG. 4 and has a reinforcing portion. The container has an opening of 1100 × 800 and a depth of 900 mm. As shown in FIG. 4, the shape has a groove that supports the lid along the outer periphery of the opening. The depth and width of the groove are 50 mm each. First, spread powder on the bottom of the container. The filling powder is about 3 cm thick. Next, the graphite material compact is placed in the container. Insert so that the direction of 600 mm is the height. Further, the filling material is covered so as to cover the graphite material compact, and the compact is submerged in the powder. Spread the packing powder to a thickness of 50 mm. The filling powder functions as a gas generator. Here, the filling powder is granular calcined coke (raw coke). The particle size of granular calcined coke is 6 mm.
Next, after placing the lid having the frame portion so as to drop into the groove of the container, the filler is filled over the entire circumference of the groove. The filler is the same calcined coke as the packing powder. Further, cover the entire circumference of the groove with mortar so as to cover the filler. The mortar functions as a coating material.
The baking container prepared in this way has an embodiment as shown in FIG. 1B and is installed in a baking furnace. The firing furnace is a gas furnace, and a combustion flame of natural gas and air is introduced into the furnace and heated. A circulation fan is provided in the furnace so that the combustion flame does not hit locally. The firing furnace is slowly heated at a rate of 3 ° C./h. As the temperature rises, hydrocarbon gas or the like is continuously released from a gas generator such as packing powder in the baking container. The released hydrocarbon gas or the like increases the internal pressure in the firing container, and releases excess gas to the outside through the gap between the groove and the lid of the container, thereby reducing the oxygen concentration in the firing container. Since the groove of the container is filled with granular filler (calcined coke), excess gas forms a one-way flow from the inside of the firing container to the outside, and the flow of the gas in the reverse direction is Less likely to occur. Furthermore, in this embodiment, the mortar is covered as a covering material. Since the mortar is cured by firing, it functions as a weight so that the filler is not spilled by the air flow of the circulation fan. Further, since the mortar is nonflammable, the filler (calcined coke) is not directly exposed to the outside air, and the oxidation of the filler can be delayed. Even if the filler is oxidized, the function of preventing the gas from entering can be maintained as long as the filler remains.
After the firing is completed, the fired body of graphite material is taken out from the packing powder of the container.
<Graphitization process>
The fired body obtained in the firing step is graphitized. Graphitization is performed in an Acheson furnace. The processing temperature is 2600 ° C. In particular, the graphitization method and the processing temperature are not limited.

  The method for producing a graphite material of the present invention provides a firing method, and any type of graphite material may be used. Moreover, the fired body obtained by the method for producing a graphite material of the present invention may be graphitized by any method and is not particularly limited.

DESCRIPTION OF SYMBOLS 1 ... Baking container, 1a ... Container body, 2 ... Groove, 2a ... Groove bottom part, 2b1 ... Groove side part, 2b2 ... Groove side part, 2c ... Groove opening, 2c1 ... Area where filler is exposed, 3 ... Accommodating Part, 4 ... bottom part, 5 ... side wall, 6 ... opening, 7 ... lattice-shaped reinforcing part, 8 ... hanging tool, 10 ... lid, 10a ... top plate part, 10b ... frame part, 11 ... graphite material, 12 ... packing Powder, 13 ... filler, 14 ... covering material.

Claims (9)

  A method for producing a graphite material in which a molded body of a graphite material is placed on a container body, a lid is placed on the opening of the container body, and the container body is closed and fired,
  The vessel body is made of metal and has a groove along the outer periphery or inner periphery of the opening,
  The lid has a frame portion made of metal and fitted into the groove,
  Closing the frame of the lid in the groove of the container, filling the groove with a powdery or granular filler, and covering the filler with a coating material made of mortar that is an inorganic paste,
  A method for producing a graphite material, comprising firing the molded body.   The method for producing a graphite material according to claim 1, wherein the molded body of the graphite material is immersed in a filling powder and fired.   3. The method for producing a graphite material according to claim 1, wherein a gas generating body that generates a non-oxidizing gas by heating is provided in a firing container including the container body and a lid.   The method for producing a graphite material according to claim 3, wherein the gas generator is an organic substance.   The method for producing a graphite material according to any one of claims 1 to 4, wherein the groove has an inner width of 10 to 100 mm.   The method for producing a graphite material according to claim 1, wherein the groove has a depth of 10 to 150 mm.   The said metal is stainless steel, The manufacturing method of the graphite material of any one of Claims 1-6 characterized by the above-mentioned.   The said container is a rectangular parallelepiped shape, The manufacturing method of the graphite material of any one of Claims 1-7 characterized by the above-mentioned.   The method for producing a graphite material according to any one of claims 1 to 8, further comprising a reinforcing portion made of ribs formed in a lattice shape on an outer surface of the container.

Images