JP5980005B2 - 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 steps.
(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 (graphite 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 at 10 ° C. per hour. A method for producing a carbon material is disclosed in which the molded body is heated and fired at the above temperature rising rate.
It is described that the heating rate is set to 10 ° C. or more per hour in order to prevent deformation of the molded body.

JP-A-60-54909

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 Document 1, conventionally, a firing container has been used to prevent oxidation of a graphite material compact.
In Patent Document 1, the temperature increase rate is described as 10 ° C. or more per hour in order to further prevent deformation, but the volume of the molded body used here is about 2000 cm ³ .
In recent years, the size of silicon wafers has increased in the single crystal pulling apparatus, which is used for graphite materials, and in the case of electric discharge machining electrodes, large graphite materials have been required, such as being used for the production of resin bumper molds. .
In recent years, a graphite material having a size of about 10 ⁶ cm ³ has been produced from such a demand. The firing rate described in Patent Document 1 is too fast for firing such a large graphite material, and the temperature difference generated inside the molded body is a thermal stress difference, dimensional shrinkage of the molded product, and a large amount from the molded product. The generation of cracked gas makes it easy to break and cannot be easily fired.
For these reasons, in recent large-sized graphite molded articles, the temperature rise rate is set so that the powder is put into a firing container and the temperature is slowly raised so as not to break. Although it becomes difficult to crack when the packing powder and the temperature rising rate are slowed down in the baking container, the longer the overall heat capacity is, the longer the baking takes, so that there is a detrimental effect on productivity and energy efficiency.
An object of the present invention is to provide a vessel, a firing container, and a production method capable of increasing the firing rate of a graphite material using the same, which can be used for firing a graphite material capable of increasing the temperature rising rate. And

The present invention relates to a container body that has an opening in the upper direction, closes the housing portion by placing a lid on the opening, and is used for firing graphite material, and the container body is a bottom wall of the container body And a space formed corresponding to the protrusion of the protrusion. The protrusion is formed so as to continuously protrude into the housing portion. The present invention preferably has the following aspects.
1a) The space is formed in a slit shape. 2a) The convex portion includes two parallel side walls, the space is provided between the two side walls, and the space between the two side walls is kept constant. 3a) The container is made of metal. 4a) The metal is stainless steel. 5a) On the outer surface of the container, there is a reinforcing portion made of ribs formed in a lattice shape. In addition, the firing container of the present invention includes the container described above and a lid, and the container further includes a groove for supporting the lid along the outer periphery or inner periphery of the opening, Is to have a frame portion that fits into the groove. The present invention preferably has the following aspects.
1b) The groove has an inner width of 10 to 100 mm. 2b) The groove has a depth of 10 to 150 mm. Further, the manufacturing method of the present invention includes a molded product of graphite material in the above-described container. Is closed so that the frame portion of the lid is submerged in the groove of the vessel body, and the groove is filled with a powdery or granular filler, and the molded body is fired. It is to be a method. The present invention preferably has the following aspects.
1c) Covering the filling material filled in the groove with a covering material made of an inorganic paste 2c) The covering material is a mortar 3c) Sintering a molded product of the graphite material in the firing container into a filling powder and firing To do

  Since the container and the firing container of the present invention have a space formed so as to continuously protrude from the bottom wall of the container into the accommodating portion, the heat of the outside air is transmitted through the space to heat the graphite material from both sides. be able to. For this reason, it becomes difficult to crack and the temperature elevation rate can be increased. In addition, since a plurality of graphite materials can be put in one container, the concentration of the outside air that has entered the firing container can be made less likely to increase compared to the case where the graphite materials are individually put in the container. It can be made difficult to oxidize. For this reason, this invention can be comprised by a simple means, and can provide the graphite material excellent in quality at low cost.

Fig.1 (a)-FIG.1 (e) are each perspective views explaining the container of embodiment of this invention. Fig.2 (a) is a figure which shows typically the cross section along the AA line of the container of Fig.1 (a). The line in the figure 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 container of (a). It is a perspective view of the container of other embodiments of the present invention. It is a figure which shows typically the cross section along the BB line of the baking container which equips the container of FIG. 3 with the lid | cover (not shown in FIG. 3) with the lid | cover. FIG. 4 shows a cross section by a vertical surface, and a line shows a cross section of a plate member having a predetermined thickness.

In the present invention, the firing container is composed of a container body and a lid, and the container body is a member made of a wall having a predetermined thickness for accommodating a molded body of graphite material, and the lid is used by covering the container 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 present invention relates to a container body that has an opening in the upper direction, closes the housing portion by placing a lid on the opening, and is used for firing graphite material, and the container body is a bottom wall of the container body And a space formed corresponding to the protrusion of the protrusion is provided.
This vessel has a graphite material accommodating portion, and forms a closed space by closing the opening with a lid.
Hereinafter, the inside of the container or firing container is indicated by the term “inside”, and the outside of the container or firing container is indicated by the term “outside”.
The container is provided with a convex part formed so as to continuously protrude from the bottom wall of the container into the accommodating part, and a space formed corresponding to the protrusion of the convex part. The convex portion functions as a wall that defines the space and forms a part of the accommodating portion. Hereinafter, this space is also referred to as a recess. The concave portion may be formed of a curved surface, a flat surface, or a combination thereof. Moreover, although a recessed part may be a continuous space or a discontinuous space, the former is preferable from the viewpoint of temperature control.
The outer surface of the convex part forms a concave part (space) and has a function of communicating (contacting) with the space outside the container body and transferring heat to the inside of the container body. The inner surface of the convex part is inside the container body. It is an element that communicates (contacts) the space and transmits the heat to the inside of the container and forms a part of the housing portion. Due to the spatial structure of the housing part described above, the graphite material placed on the housing part is more efficiently and effectively transmitted from both the convex part and the wall of the vessel other than the convex part. It is difficult for the temperature difference to occur inside, and the above effects can be exhibited.
The container housing part is composed of a bottom wall and a side wall, and the side wall is composed of a first side wall constituting a part of the convex part and a second side wall not constituting a part of the convex part. It is preferable.
And it is preferable that the said convex part is a wall element which comprises the accommodating part in which a graphite material is mounted, and has a function divided into at least 2 or more rooms.
A plurality of concave portions or convex portions used in the present invention can be provided in the container.

  The recess (space) of the present invention is preferably formed in a slit shape. Since the concave portion is formed in a slit shape from the bottom wall of the container, it is possible to form an air flow that flows from the bottom of the slit to the side, so heat exchange between the first side surface of the convex portion and the outside air is efficient. Can be done well.

  It is preferable that the convex part of the present invention includes two parallel side walls, a concave part (space) is provided between the two side walls, and a reinforcing member is provided to keep the distance between the two side walls constant. Such a convex part divides or partitions the lower side of the container into two. For this reason, it becomes easy to apply stress to the convex part of the container. For this reason, the stress concerning a convex part can be made small by putting a reinforcement member. It is preferable that the reinforcing member is partially formed so as to form a flow path connecting from the bottom of the recess to the side. By being formed partially, an airflow flowing from the bottom to the side can be formed.

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 constructed integrally by welding, etc., and the strength of the seam part such as the welded part is high. A complicated shape can be easily obtained.
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 prismatic bodies such as prisms and cylinders, and a rectangular parallelepiped is preferable because a plurality of graphite materials can be efficiently packed even if they have convex portions or concave portions.

  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.

A firing container according to the present invention includes the container described above and a lid, and the container further includes a groove that supports the lid along an outer periphery or an inner periphery of the opening. It is preferable to have a frame portion that fits into the groove.
The structure and shape of the lid are basically arbitrary as long as the lid has a frame portion having a function of covering the opening of the container. 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 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.

  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 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 the inner distance between the groove side portions, and the depth is the distance from the inner surface of the groove bottom 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 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 firing method of the present invention, a graphite material compact is placed in the container of the present invention, and the lid frame is closed so that the frame of the lid is submerged in the container, and a powdery or granular filler is placed in the groove. It is a method for producing a graphite material, which is filled and fired.
In the manufacturing method of the present invention, the firing container includes a container and a lid, and the container indicates a member that accommodates a molded body of graphite material, and the lid is a member that is used by covering the container. Show. 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 upper direction, a cover is placed on the opening to close the accommodating portion, and the container is used for firing the graphite material. It has this recessed part (space).
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.
The container 1 of the present invention has a convex portion 2A, a concave portion (space) 2B, and is formed of a plate material having a desired thickness, which includes an accommodating portion 3, a bottom wall 4, a second side wall 5, and an opening 6. Yes. A container body 1 shown in FIGS. 1 (a) and 2 (a) includes a convex part 2A formed so as to continuously protrude from the bottom wall 4 of the container body 1 into the housing part 3, and the convex part 2A. A recess (space) 2B formed corresponding to the protrusion of the portion 2A is provided, and the recess (space) 2B is formed in a slit shape. The convex portion 2A includes first side walls 2a and 2b and a wall 2c perpendicular to the side walls. These three walls represent walls communicating with (in contact with) the inside of the body 1 or the outside of the body 1, have a certain thickness and form a part of the body 1, the bottom wall 4, and the second side wall 5. In addition, the housing portion 3 is formed, and the convex portion 2A and the concave portion (space) 2B are formed. The container body 1 is divided or partitioned into two or more accommodating portions by the presence of the convex portion 2A and the concave portion (space) 2B (in FIG. 1A and FIG. 2 to 4 or 5 storage units in (c), 4 storage units in (d), 3 storage units in (e). It is obvious that the bottom wall 4 and the second side wall 5 are also walls that communicate (contact) with the inside of the vessel 1 or the outside of the vessel 1 similar to the convex portion 2A. Usually, one graphite material is placed in one housing portion, but a plurality of graphite materials can be placed in one housing portion according to the shape of the graphite material and the shape of the room.

The convex portion 2A and the concave portion (space) 2B in FIG. 1B is a wall 2d, whereas the bottom wall 4 direction of the convex portion 2A and concave portion (space) 2B in FIG. The space between the surface of the wall 2d that communicates with the interior of the container and the surface of the bottom wall 4 that communicates with the interior of the container is a part of the accommodating portion 3.
The convex portion 2A and the concave portion (space) 2B in FIG. 1C are a space where the concave portion (space) 2B in FIG. The difference is that the space 2B) is formed. The configuration and function of the wall 2e are the same as 2d and the like.
The convex part 2A and the concave part (space) 2B in FIG. 1D are the same as the convex part 2A and the concave part (space) 2B in FIG. The number of the accommodating parts 3 is four. The two recessed portions (spaces) 2B that intersect may be a continuous space or may be a space that is intermittent between the intersecting portions.
The convex part 2A and the concave part (space) 2B in FIG. 1 (e) are formed in parallel with two convex parts 2A and concave parts (spaces) 2B in FIG. . Such a thing is the same also about Drawing 1 (b)-(d), or it can choose suitably from the mode of Drawing 1 (a)-(d), and can also use it together.
Since the concave part (space) 2B is formed in the container 1 as described above, the air flow outside the container is easily convected in the concave part, and the first side walls 2a and 2b of the container and the second side wall 5 is heated from both sides, so heat transfer to the graphite material can be performed smoothly.

Fig.2 (a) is a figure which shows typically the cross section along the AA line of the container of Fig.1 (a), and the line of the figure has shown the cross section of the board | plate material which has predetermined | prescribed thickness. . In FIG. 2 (a), the container 1 of the present invention has the convex portion 2A and the concave portion (space) 2B as described above, and the accommodating portion 3, the bottom wall 4, the second side wall 5, and the opening 6. It is formed with the metal plate material of desired thickness provided.
The convex portion 2A includes first side walls 2a, 2b, and a wall 2c, and forms a concave portion (space) 2B.
FIG.2 (b) is a schematic diagram which shows an example of the use condition of the container 1 of Fig.2 (a).
The vessel body 1 is covered with a lid 10 as shown in FIG. The lid 10 includes a top plate portion 10a and a frame portion 10b.
Further, in FIG. 2A, the vessel 1 further has a groove 5a as shown in FIG. The groove 5a includes groove side parts 5a1, 5a3 and a groove bottom part 5a1. The groove side portion 5a3 is formed as a part of the second side wall 5 by joining the end portion of the bottom portion 5a1 of the plate member having an L-shaped cross section to the second side wall 5 by welding. The opening 6 is covered with the top plate portion 10a, and the frame portion 10b is fitted into the groove 5a.
FIG. 2B shows the graphite material 11, the packing powder 12, the filler 13, and the coating material 14 when the graphite material 11 is placed in a firing device and fired using the firing container 100. 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 in the groove 5a, the groove opening 5a4 formed by the frame portion 10b and the groove side portion 5a2. Of these, the region 5 a 41 where the filler 13 is exposed may be blocked by the covering material 14. The coating | covering material 14 may be given to the groove | channel side part 5a2 and the top-plate part 10a.

Moreover, in the aspect of the container of FIG. 3, the reinforcing member 2f which keeps a fixed space | interval is inserted between the 1st side walls 2a and 2b of 2 A of convex parts. By this reinforcing member, the convex portion 2A and by extension the concave portion (space) 2B are not easily deformed, and the heat transfer performance can be maintained.
The container body 1 has lattice-like ribs 7 on the surfaces of the bottom wall 4 and the second side wall 5. The hanging tool 8 is used when the firing container 100 is moved.
Further, a groove 5 a is provided along the opening 6. As shown in FIGS. 3 and 4, the groove 5a is composed of a groove bottom part 5a1, groove side parts 5a2, 5a3, and has a groove opening 5a4, as in FIG. 2B. The groove side portion 5a3 is formed by joining the end portion of the groove bottom portion 5a1 of the L-shaped plate material to the second side wall 5 by welding. The opening 6 is covered with a lid 10, specifically, a top plate portion 10a, and the frame portion 10b is fitted in the groove 5a.
As shown in FIG. 2B, when the filler is put into the groove 5a, the region where the filling powder is exposed in the groove opening 5a4 formed by the frame portion 10b and the groove side portion 5a2 is covered with the covering material. It may be blocked. The covering material may be applied to the groove side portion 5a2 and the lid 10.

  In the above specific embodiment, an example in which the accommodating portion and the concave portion have a rectangular parallelepiped shape has been described. However, the accommodating portion and the concave portion may be cylindrical or the like, and the graphite material may be a donut-shaped column or the like. Moreover, it is clear from the above that the shapes of the accommodating portion and the recess are not limited to the above.

  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 can be used under any conditions.
<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 350 × 600 × 1000 mm. The molding method and molding pressure are 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. 3 and has a reinforcing portion. As shown in FIG. 3, the shape of the vessel has an opening of 1100 × 900 and a depth of 900 mm. The accommodating part is divided into two by a recess having a height of 800 mm and a width of 50 mm. The internal dimensions of the individual accommodating portions are 1100 × 425 × 900 h. (900h is the height direction.) The vessel has a groove for supporting 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 firing container prepared in this way has an embodiment as shown in FIG. 2B and is installed in a firing 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. The heated gas emitted from the burner is transferred from the outside of the firing container (container) including the recesses and from the inside of the firing container (container) including the projections to the housing portion, and the graphite compact is formed from both sides. Heated. 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 ... Container body, 2A ... Convex part, 2B ... Concave part (space), 2a, 2b ... 1st side wall, 2c, 2d, 2e ... Wall, 2f ... Reinforcement member, 3 ... Accommodating part, 4 ... Bottom wall, 5 2nd side wall, 5a ... groove, 5a1 ... groove bottom, 5a2 ... groove side, 5a3 ... groove side, 5a4 ... groove opening, 5a41 ... area where filler is exposed, 5b ... hanging tool, 6 DESCRIPTION OF SYMBOLS ... Opening, 7 ... Rib, 10 ... Lid, 10a ... Top plate part, 10b ... Frame part, 11 ... Graphite material, 12 ... Packing powder, 13 ... Filling material, 14 ... Covering material, 100 ... Firing container.

Claims (10)

  A method for producing a graphite material in which a molded body of a graphite material is placed in a container housing portion, submerged in a filling powder, and then fired by placing the lid on the opening of the vessel body and closing the vessel body,
  The container is made of metal, and the container is divided into two or more by a convex part including two parallel side walls formed so as to continuously protrude from the bottom wall of the container into the container. , A molded body of graphite material is disposed in each of the two or more divided accommodating portions,
  A method for producing a graphite material, comprising: a reinforcing member that maintains a constant interval between the two side walls in a slit-like space formed corresponding to the protrusion of the convex portion.   The method for producing a graphite material according to claim 1, wherein the outer surface of the vessel body has reinforcing portions formed in a lattice shape and made of ribs.   The vessel further has a groove for supporting the lid along the outer periphery or inner periphery of the opening,
  The method for producing a graphite material according to claim 1, wherein the lid has a frame portion that fits into the groove.   The method for producing a graphite material according to claim 3, wherein the groove is filled with a powdery or granular filler.   The method for producing a graphite material according to claim 4, wherein the filler filled in the groove is further covered with a coating material made of an inorganic paste.   The method for producing a graphite material according to claim 5, wherein the covering material is mortar.   The said groove | channel is a manufacturing method of the graphite material of any one of Claims 3-6 whose inner width is 10-100 mm.   The said groove | channel is a manufacturing method of the graphite material of any one of Claims 3-7 whose depth is 10-150 mm.   The said container is a manufacturing method of the graphite material of any one of Claims 1-8 which consists of stainless steel.   The method for producing a graphite material according to any one of claims 1 to 9, wherein the vessel body has a rectangular parallelepiped shape.

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