JP2003292376A - Device for manufacturing graphite block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for manufacturing a graphite block which reduces the cost of a graphitization process and shortens its lead time by stopping the filling a packing powder which causes a variety of undesirable phenomena in applying a direct energization method. <P>SOLUTION: This device for manufacturing the graphite block comprises the steps of: forming an original block by firing a carbon material aggregate, a binder and a catalyst contained therein to accelerate the graphitization; holding and pressurizing the original block directly to an electrode so that the block can be energized; heating by energization the original block by directly focusing on the original block in vacuum or in an inert gas atmosphere without existing the packing powder around the raw block and the electrode; thereby forming a high density graphitized part inside the block and a precipitated catalyst element part on the surface part; and forming the graphite block by removing the precipitated catalyst element part by grinding, or the like. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a graphite block manufacturing apparatus.

[0002]

2. Description of the Related Art In a graphitizing furnace, a raw block obtained by firing a material composed of a carbon material aggregate, a binder and a catalyst or a graphite crucible is arranged alternately with a packing powder made of coke, and further, a packing powder made of coke is placed around them. An indirect energization method is known in which graphitization is performed by energizing electrodes placed on both sides by filling with.

Japanese Examined Patent Publication No. 54-3682 discloses a high-density graphite molded body obtained by adding boric acid as a sintering accelerator to amorphous carbon powder or artificial graphite powder containing no binder and firing it under pressure. Is described.

Further, Japanese Patent Laid-Open No. 5-78111 discloses that
A method for producing a graphite material is described, in which a plurality of fired bodies are bonded together, a packing powder is filled in a graphitization furnace, and the fired bodies are electrically heated to be graphitized under pressure from electrodes at both ends.

Further, Japanese Patent Laid-Open No. 5-78112 discloses that
A plurality of carbon fired bodies having carbonaceous slurries applied to both end faces are arranged in a straight line in the longitudinal direction of the graphitization furnace through the carbonaceous slurries with the end faces facing each other, and the graphite furnace is filled with powdered powder. It describes a method for producing a graphite material which is filled and graphitized by electrically heating the fired body under pressure from electrodes on both ends of the fired body.

[0006] Further, in Japanese Patent Laid-Open No. 2000-73105, there is a front chamber in which a powder material introduced through an inlet door is placed in a vacuum atmosphere, and a powder which is downstream from the front chamber and is conveyed from the front chamber. An energizing hot press chamber in which the raw material is taken into a mold surrounded by a heat insulating material by a grabber and an energizing heating device and a resistance heating device enclosing the mold are used to pressurize and heat at the same time to form a pressure-molded material. A cooling chamber that is located downstream of the hot press chamber and that cools the pressure-formed material that has been heated from the energizing hot press chamber to a predetermined temperature, and a processing chamber that is located downstream of the cooling chamber and that is carried from the cooling chamber. A rear chamber that returns the pressure-formed material from the vacuum state to the atmosphere and carries it out from the outlet door, a conveying device that sequentially conveys the powder raw material or the pressure-formed material to the front chamber to the rear chamber, and the front chamber to the rear chamber. Airtight at each entrance and exit It describes a continuous heat pressing apparatus to place the partition door with.

[0007]

As described above, as described above,
When the original block is formed by firing and graphitized by high-temperature heat treatment, coke or other filling powder is filled around the bonded multiple original blocks, or the original block and coke or other filling powder are arranged alternately. However, there is known an electrically heating type graphitization method and apparatus in which a packing powder such as coke is further arranged around these and electricity is applied between the electrodes. In this method and device, an electric current is applied to the fired body that is the original block to heat the fired body itself to perform graphitization treatment (direct energization method). Is a system for heating and heating as a heating body and for keeping heat and preventing oxidation, and is characterized in that the temperature is raised to around 3000 ° C. with the help of the filled powder. Therefore, according to this method and apparatus, a large amount of input power is required to heat the packing powder, and a large amount of packing powder is removed and disposed of after the high temperature treatment, which is an obstacle to improvement of operability due to continuity. There is. In addition, it is difficult to make the resistance value of the filling powder portion filled around the sintered body constant, the current in the furnace is biased, partial temperature rise easily occurs, and the electrode resistance is high in the temperature rise portion. A decrease causes a large amount of current to flow, further raising the temperature of that portion, which causes a temperature difference in the fired body, which causes cracking.

In view of the above, the present invention aims at reducing the cost of the graphitization process and shortening the lead time by stopping the filling of the packing powder which causes the above-mentioned various undesirable phenomena when adopting the direct energization method. An object of the present invention is to provide a graphite block manufacturing apparatus capable of manufacturing the graphite block.

According to the present invention, a graphite block is produced by using an original block formed by firing containing an aggregate that is a carbon material, a binder, and a catalyst that promotes graphitized crystals. An object of the present invention is to provide an apparatus for producing a graphite block, in which the precipitation portion is limited and surface finishing is easy. Another object of the present invention is to provide a graphite block manufacturing apparatus that enables continuous graphitization.

[0010]

According to the present invention, coke powder, coal tar pitch, and optional catalyst (for example, metals such as iron, nickel, titanium, silicon and boron, their carbides and oxides). ) Is heated and kneaded, crushed,
It is molded and fired to form a raw block (carbon block), and graphitization is performed in the absence of packing powder to directly form a graphitized block or a graphite block. The generated graphite block is subjected to processing such as powder treatment, if necessary. As described above, the absence of the packing powder is an important matter for the present invention, but the presence of the powder under the situation where the effect as the packing powder cannot be expected is not excluded. As a matter of course, due to the absence of dust, the surrounding area of the original block becomes a space.

The present invention solves one or more of the above problems with a graphite block manufacturing apparatus described below. The present invention relates to a graphitizable carbon molded product, for example, a graphite block manufacturing apparatus that performs graphitization by high temperature heat treatment of an original block containing at least a carbon material aggregate and a binder and fired, A pair of electrodes for energizing and holding the original block, a vacuum forming device or an inert gas charging device, and a pressurizing device for pressing the held original block in the electrode direction via the electrodes,
And a current-carrying device for supplying current to the electrode, and a high-temperature heat treatment device for performing graphitization treatment by the heat generated in the raw block itself in the absence of packing powder around the electrode and the raw block, that is, with the surrounding space. An apparatus for manufacturing a graphite block having the above is provided.

The present invention is an apparatus for producing a graphite block in which at least a carbon material aggregate, a binder, and a catalyst that promotes graphitization are contained and fired, and the raw block thus formed is graphitized by high-temperature heat treatment. A pair of electrodes for energizing and holding the original block (including the case where it is directly sandwiched between the electrodes and arranged in parallel), a vacuum forming device or an inert gas charging device, and the electrodes And a high-temperature heat treatment apparatus equipped with a pressurizing device for pressurizing the held original block in the electrode direction, and an energizing device for energizing the electrode, and a high-density graphite inside by a graphitization treatment by the high-temperature heat treating device Provided is a graphite block manufacturing apparatus, which comprises a surface finishing device for surface-finishing a catalyst component precipitation portion formed on a surface portion of a chemical conversion portion by grinding or the like.

The present invention makes it possible to energize a single original block in a graphite block manufacturing apparatus for graphitizing by high temperature heat treatment of an original block formed by firing containing an aggregate of carbon material and a binder. A pair of electrodes for holding the same, a vacuum forming device or an inert gas charging device, a pressurizing device for pressurizing the held original block in the electrode direction through the electrodes, and an energizing device for energizing the electrodes. A high-temperature heat treatment apparatus for performing graphitization treatment by the heat generated in the original block by collecting current concentrated in the original block through the electrode in the absence of a packing powder around the electrode and the original block, And a transfer space chamber provided with another vacuum forming device or an inert gas charging device and a transfer device for transferring the loaded original block to the high temperature heat treatment device. To provide a manufacturing apparatus of a graphite block, characterized in.

According to the present invention, the high-temperature heat treatment apparatus is further positioned adjacent to the high-temperature heat treatment apparatus on the other side of the transfer space chamber so as to be flush with the high-temperature treatment apparatus and the transfer space chamber. Provided is a graphite block manufacturing apparatus provided with a surface finishing chamber equipped with a surface finishing device by grinding a catalyst component precipitation portion formed on a surface portion of a high-density graphitized portion inside by chemical treatment.

The present invention further provides a graphite block manufacturing apparatus in which a heat reflection plate is provided around the original block with a gap interposed. The present invention further provides a graphite block manufacturing apparatus in which a carbon sheet is disposed between an electrode and an original block.

As the raw material of the above-mentioned carbon molded body, there are generally a graphitizable carbon molded body or a graphitizable carbon molded body containing a catalyst for promoting graphitization. Specifically, (A) A two-component system containing an aggregate which is a carbon material and (B) a binder, (A) an aggregate, (B) a binder and (when a component other than a catalyst is contained, it may be treated as a two-component) (C) There are three-component systems that include a catalyst that promotes graphitized crystals (if other components are included, they may be treated as three-component). The above (A) and (B) or (A), (B) and (C) produces an original block that is a graphitizable carbon compact.

Examples of aggregates include cokes obtained from coal and petroleum, oil smoke, carbon black artificial graphite obtained by firing a phenolic resin-based or rubber-based polymer, and natural graphite. The particle size of these aggregates is 0.1 to 3
00 μm is preferable, and 1 to 50 μm is particularly preferable.
When the particle size of the aggregate is less than 0.1 μm, the aggregate particles are secondarily aggregated to deteriorate the kneading property, and when it exceeds 300 μm, the desired effects of electric properties and sliding properties may not be obtained.

Examples of the binder include tar pitch, coal tar, synthetic resins such as phenol resins and melamine resins, and rubber polymers such as butadiene and urethane. Examples of the catalyst include iron, nickel,
Examples thereof include metals such as titanium, silicon and boron, and their carbides and oxides.

In an embodiment of the present invention, the above (A)
The mixing ratio of the aggregate and the (B) binder is 100
The binder is preferably 10 to 300 parts by weight, more preferably 70 to 150 parts by weight, based on parts by weight. If the amount of the binder is less than 10 parts by weight, the adhesion between the aggregates is not sufficient, and a good block molded product may not be obtained. Also,
If the amount of the binder exceeds 300 parts by weight, the desired electric characteristics and sliding characteristics may not be obtained.

When the raw material is a three-component system, the mixing ratio of (A) aggregate and (B) binder and (C) catalyst, the mixing ratio of aggregate and binder are the above two-component system mixing ratio. The amount of the catalyst is preferably 1 to 50 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the aggregate. When the amount of the catalyst is less than 1 part by weight, graphitization becomes non-uniform and the desired crystalline graphite may not be obtained. Catalyst is 5
If it exceeds 0 part by weight, the catalyst may not be efficiently deposited on the surface of the block molded article during firing, and the desired effects of electrical characteristics and sliding characteristics may not be obtained.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a graphite block manufacturing apparatus 1 used in an embodiment of the present invention. In the figure, a graphitization treatment chamber 2 includes a carry-in space chamber 4 that is an inlet portion of an original block 3 and a high-temperature heat treatment apparatus 6 located in the center.
And a carry-out space chamber 8 accommodating the graphitized graphitization block 7. Carrying out space room 8
A surface finishing chamber 9 in which a cutting device such as a grinder 10 is placed is arranged adjacent to the. Therefore, the carry-in space chamber 4 and the carry-out space chamber 8 are arranged so as to face each other with the high-temperature heat treatment chamber 5 as the center. Carry-in space room 4, high temperature heat treatment room 5,
The carry-out space chamber 8 and the surface finishing chamber are arranged in series, and are arranged on a uniform horizontal plane.

In FIG. 1, the graphitization processing chamber 2 has a double-part chamber with the central chamber serving as the high-temperature heat treatment chamber 5, but may be constructed as separate chambers. Graphitization treatment room 2
Vacuum pumps 12 and 13, which are vacuum forming devices, are connected to the high temperature heat treatment chamber 5 and the high temperature heat treatment chamber 5, respectively. In the present invention, “vacuum” refers to a dilute gas state in which the pressure is lower than normal atmospheric pressure, and does not refer to a virtual state in which gas molecules do not exist at all.

An inert gas charging device (not shown) is provided instead of or in parallel with the vacuum pumps 12 and 13 to supply the inert gas into the graphitization processing chamber 2 and the high temperature heat treatment chamber 5. To be able to.

A plurality of original blocks carried by the trolley 15 are carried into the carry-in space chamber 4 by a carrying-in device such as a robot (not shown) or by an operator, and the original blocks are conveyed one by one to the conveyor 16 or the like. It is carried into the high temperature heat treatment chamber 5 by the transfer device. Of course, the worker may do it. The carry-in space chamber is a first vacuum or inert gas atmosphere chamber, and the high temperature heat treatment chamber 5 is a second vacuum or inert gas atmosphere chamber. The high temperature heat treatment chamber 5 has an inlet 17 and an outlet 18.

The high temperature heat treatment apparatus 6 disposed in the high temperature heat treatment chamber 5 is provided with two electrodes 21 and 22, which are horizontally (face-to-face or in any other direction) and face each other, and electrodes 21 and 22, respectively. Pressurizing devices 23 and 24 (pressurizing devices 23 and 24) that are movable in the horizontal electrode direction.
Also has a function as a holding device for holding the electrodes 21 and 22), and further, an energization device 25 that energizes the electrodes 21 and 22, and a computer device 2 that controls power-on.
6 (control device). The electrodes 21 and 22 may be energized by direct current or alternating current.

The original block 3 is held by being sandwiched between the electrodes 21 and 22, and is pressed by the pressure devices 23 and 24, so that the electrode 2
Make sure that the contact with 1, 22 is sufficient. Here, the original block 3 is directly held by both electrodes 21 and 22. Direct holding includes holding by the electrodes 21 and 22 and holding by interposing a carbon sheet having good conductivity as will be described later. In such a case,
It may be regarded as an electrode including the carbon sheet. Therefore, the term "directly energize" includes the case of energizing through a material having good conductivity such as a carbon sheet.

The high temperature heat treatment apparatus 6 does not need to fill the raw block 3 and the electrodes 21 and 22 with packing powder such as coke. In short, electricity is applied to the surroundings of the original block 3 and the electrodes 21 and 22 in the absence of the dust as described later.

A reflection plate (not necessarily a flat plate) 27 is arranged around the original block 3 in the vertical direction and / or the horizontal direction with a gap. The reflection plate 27 has a function as a heat reflection plate and has a function of returning the heat radiated from the original block 3 to the original block 3.

When the electrodes 21 and 22 are energized by the energizing device 25, electricity is concentrated and collected in the original block 3 because there is no clogging in the surroundings and flows. By this concentrated power input, the heat generated in the original block 3 itself causes the original block 3 to move to 3
The temperature is raised to around 000 ° C. Since there is no packing powder in the surroundings, the current can be made to flow uniformly in the original block 3. It is important to make the current flow to the original block 3 evenly in order to manufacture a uniform product. When the packing powder is present in the surroundings, the current also flows in the packed packing, so that the current does not flow evenly. This is one of the reasons why the packing is not filled around the original block 3, that is, the processing is performed in the absence of the packing.

Further, the action of the reflection plate 27 returns heat to the original block 3 to help maintain 3000 ° C.

FIG. 3 illustrates the current flow in this embodiment as a comparative example using an Acheson furnace as a conventional graphitizing furnace. In the present embodiment, one original block is sandwiched between the electrodes, and since no packing powder is present around the electrodes, the current flows to the original block and does not flow to the other parts. On the other hand, in the Acheson furnace, as shown in the figure, the electric current flows not only into a plurality of raw blocks arranged in parallel but also into the packing powder such as coke, resulting in a large loss.

In the present embodiment, it is not necessary to fill at least the stuffing powder, and the most desirable form is to be in a spatial state. This also means that the current is concentrated in the original block 3 as shown in FIG. The electric current supplied by this is effectively used for temperature rise, that is, graphitization.

FIG. 4 illustrates the state of deposition of catalyst components in the case of the structure shown in FIG. In this example, the graphitization catalyst component is deposited on the surface of the original block. still,
As a matter of course, if no catalyst is used in the original block, no precipitate is formed. When an Acheson furnace is used, graphitization catalyst deposits adhere to the packing powder of coke, etc., and the processing of the packing powder after the graphitization treatment requires a great deal of cost and labor, which is an obstacle to continuity. .

FIG. 5 shows a comparison of heating and cooling times. In this embodiment, heating up to around 3000 ° C. is performed within 5 minutes (min), and cooling is performed within 10 minutes. Especially, this time setting is important when the graphite block is used for a battery. Even in the case of other uses, it is desirable to carry out the treatment within 30 minutes. That is, rapid heating and rapid cooling are performed. Therefore, the high-temperature heat treatment chamber 5 can be called a high-speed high-temperature heat treatment chamber, and the term "high-speed" here means a treatment within 30 minutes, preferably within 10 minutes. On the other hand, in the Acheson furnace, a plurality of original blocks are processed at one time, but the time required for this processing is 30 days (day), which makes management difficult. The raw block 3 can be graphitized by high temperature heat treatment to form a graphitized block.

When the original block 3 contains the three components as described above and contains the catalyst, the graphitized block is formed in the high density graphitized part of the inner part and the periphery of the graphitized part, that is, the surface part. It is composed of the deposited portion where the catalyst component is deposited.

In the direct energization method using the stuffing powder, the stuffing powder itself generates heat and is heated, so that the catalyst component is deposited on the stuffing powder. In the case of this embodiment, since the packing powder is absent, the catalyst component is deposited by forming a thin layer of 1 to 1.5 mm on the skin portion of the generated graphitized block, that is, the surface portion. This has important implications for the recovery and surface use together with the removal of the catalyst component.

In the present embodiment, the above catalyst is deposited and adhered to the surface of the molded article or volatilized in the firing furnace in the process of firing the block molded article for graphitization (conventional packing powder is used). According to the method used, as described above, deposits are deposited and adhere to the filling powder). Deposition on the surface of block moldings,
The attached catalyst component can be removed and collected by grinding. Further, the volatilized catalyst component can also be recovered by a means such as providing a cooling recovery device that is passed through the incinerator. For example, when silicon carbide is used as a catalyst, silicon carbide is deposited in the vicinity of the surface of a graphitized block molded product (the deposition thickness of silicon carbide is 5 to 30 mm for a block size of 300 mm × 200 mm × 150 mm), and block molding is performed. A graphite layer in a homogeneous state with almost no catalyst is formed inside the product. The silicon carbide ground and removed from the surface of the molded product can be regenerated and repeatedly used.

The formed graphitized block is carried out as the graphitized block 7 into the carry-out space chamber 8 by the transfer device such as the conveyor 31 and held therein. This graphitized block 7
Is appropriately transferred to the surface finishing chamber 9, and the above-mentioned deposit is removed by a cutting device such as a grinder 10 for surface finishing.

When the graphitized block 7 is surface-finished and is made of a binary component material without surface-finishing, the graphitized block 7 is used as it is (however, the deposit is removed) to form the graphite block 32. It is taken out of the surface finishing chamber 9 and transferred by the carriage 33. A dust collector 34 is attached to the surface finishing chamber 9 to clean the interior.

FIG. 2 shows a situation in which the original block 3 is sandwiched between the electrodes 21 and 22. The original block 3 is an electrode 21,
It is held via carbon sheets 41 and 42 arranged on the surface 22. Carbon sheet 4 before heat treatment
Although 1 and 42 are independent bodies, after the heat treatment, they adhere to the generated graphitized block, so handling including taking out is extremely easy.

A carbon cylinder 44 as a reflector is arranged around the original block 3 with a gap 43. Here, the carbon cylinder 44 will be collectively referred to as the reflection plate 17 in FIG.

The second embodiment of FIGS. 6 to 8 is shown in more detail than the previous embodiment. The same configurations as those of the previous embodiment are denoted by the same reference numerals and the description thereof may be omitted. The basic configuration is the same as that of the previous embodiment, and the description of the above embodiment applies to most of them. FIG. 6 is a plan view of the entire device of the second embodiment, FIG. 7 is an elevational view thereof, and FIG. 8 shows an electrode portion structure, which corresponds to FIG. 2 of the previous embodiment.

In these figures (FIGS. 5 to 8), on the introduction side of the original block 3 located in front of the carry-in space chamber 4,
An adhesive material application chamber 51 (hood for adhesive material application device) is provided.

A transfer device 52 is provided to horizontally penetrate through the adhesive material application chamber 51, the loading space chamber 4, the high temperature heat treatment chamber 5, the unloading space chamber 8 and the surface finishing chamber 9. Therefore, the original block 3, the graphitization block 7 and the graphite block 32 are transported on the transport device 52. The operation of the carrier device 52 is controlled by the carrier device controller 70.

In the adhesive material application chamber 51, an adhesive material application device 53 as an adhesive material application device 50, an air cylinder 54 for discharging a carbon sheet, a series of carbon sheet groups 55, and a carbon sheet extruding device are arranged along a conveying device 52. The air cylinder 56 is provided, and one carbon sheet (one sheet on one side and one sheet on the other side) extruded by these devices is bonded to both sides of the original block 3 and flows on the transport device 52.

In this example, copper members 61 and 62 are provided between the electrodes 21 and 22 and the pressurizing devices 23 and 24, and the pressurizing devices 23 and 24 have these copper members 61 and 62. 62
Then, the original block 3 sandwiched via the electrodes 21 and 22 is pressed via the. The pressurizing devices 23 and 24 are composed of air cylinders or hydraulic cylinders. The pressure devices 23 and 24 are provided with load cells 63 and 64.

A transformer 65 (either AC or DC) is connected to the copper members 61 and 62 by a wiring 67, and the input power is controlled by a power control board 66. This power control board 66 is the computer device 26 of the previous embodiment.
And the transformer 65 corresponds to the energization device 25. The electrodes 21 and 22 are provided with a pair of heat shields 68.
This has an effect equivalent to that of the reflector 27 of the previous embodiment.

An elevating device 69 for the original block 3 is provided on the lower side of the transport device 52, and the original block 3 is individually lifted between the electrodes 21 and 22 one by one.
Sandwiched by two. The heat shield device operating devices 61 and 62 are connected to the pair of heat shield portions 68, respectively.

The high temperature heat treatment chamber 5 has a door 63 on the inlet side of the heating chamber.
Further, the heating chamber outlet side door 64 is provided, the atmosphere introduction pipe 65 for high heat treatment is provided, and the atmosphere throttle valve 66 is provided in the atmosphere introduction pipe 65. Inert gas is introduced from the atmosphere introducing pipe 65. High temperature heat treatment chamber 5
An exhaust gas discharge pipe 67 for discharging the exhaust gas generated in the above is provided, and the impurity decomposition device 68 is provided in the exhaust gas discharge pipe 67.
And an exhaust pump 69.

An atmosphere throttle valve 71 and an exhaust pump 72 are provided in the carry-in space chamber 4 for atmosphere control in the same manner as described above. Further, the entrance door 73 is provided at the entrance of the carry-in space room 4.
However, an exit door 74 is provided at the exit of the carry-out space chamber 8.

The surface finishing chamber 9 is also a hood for collecting dust,
The dust collector 81 and the blower 82 are connected to collect dust.
In the surface finishing chamber 9, a cutter 93 and a surface finishing device 94 are provided along the transfer device 52.

In FIG. 8, electrodes 21, 22 are provided with replacement graphite electrodes 83, 84, and these replacement graphite electrodes 8 are provided.
The pair of carbon sheets 35 may be adhered and held by 3, 84. Electrodes 21, 22, copper member 6
Cooling water circulation pipes 85 and 86 are provided in the Nos. 1 and 62, respectively, and the cooling water flows to cool the electrodes 21 and 22 and the replacement graphite electrodes 83 and 84.

Next, the situation where the graphitization characteristics of the prototype are evaluated will be described. Table 1 shows an outline of the apparatus used for evaluation.

[0054]

[Table 1]

FIG. 9 shows a flow for energizing. In the figure, an original block and a carbon sheet are sandwiched between electrodes (S1), and the original block is surrounded by a carbon cylinder (S2). Secure the original block with a pressure device (13MP
a) (S3), the atmosphere is evacuated to 13 Pa (1.2
7 × 10 ⁻⁴ atm) (S4), replaced with an inert gas (argon or nitrogen) (S5), and set the atmospheric pressure to 6
The pressure was adjusted to 6 kPa (0.66 atm) (S6). After that, electricity was applied (S7). The test was performed on Samples 1 to 8 by changing the applied power and the applied time. The influence of the temperature rising rate on the graphitization characteristics of the graphite block manufactured by this was investigated. As a result, the temperature rise rate is 150 ℃
It was found that the graphitization characteristics were not affected even when the temperature was changed from / min to 500 ° C / min. 500 ° C / min
Is the average heating rate of the Acheson furnace, 2 ° C / mi
It is 300 times larger than n. It was found that the power consumption rate could be improved by further increasing the temperature rising rate.

The influence of the atmosphere was examined under the constant conditions of maximum input power (47 kW), holding time (about 6 min) and temperature rising rate (500 ° C./min). As a result, it was found that the graphitization characteristics were all good values and that the atmosphere did not affect the product characteristics.

FIG. 10 shows steps in evaluating graphitization characteristics. After trial manufacture, remove the surface deposits from the test piece and measure the weight reduction rate by weight measurement.
Outer cutting (thickness 1.0 to 1.5 mm) was performed, and ash content, specific resistance, lattice constant, etc. were measured and evaluated.

FIG. 11 shows the evaluation result. Good results could be obtained except for test piece No. 2 and test piece No. 6.
FIG. 12 shows a battery characteristic good range ◯ and a characteristic unachieved region × in relation to the maximum input power with respect to the maximum input power holding time. These tests have revealed that optimum graphitization conditions exist. Therefore, the conditions for producing graphite with this production apparatus are preferably as follows.

The larger the electric power and current value applied to the block molded product, the better the graphitization characteristics.
However, if the applied power is too high, bumping may occur inside the block material and damage may occur. On the other hand, graphitization does not proceed when the input power is below a predetermined power (current). Also,
The size of the block molding determines the range of input power and current required for graphitization. Therefore, as the block size, the cross-sectional area of the surface that contacts the electrode is 2,5
00 to 40,000 mm ² and a length of 200 to 50
Is preferably 0mm rectangular parallelepiped, the density of the molded article is preferably 1.0~1.8g / cm ^3, more preferably 1.3~1.6g / cm ^3. Input power and current vary depending on the block size, but in the above size, 500 to 1,300 kW
(Current of 15,000 to 50,000 A) is preferable. Specifically, the size of the block molded product is 100 mm × 10
In case of 0 mm x 300 mm, input power is 500 to 600
kW (current 15,000 to 25,000 A) is preferable. Also, the block size is 150 mm x 150 x 300
In case of mm, input power 900 to 1,100 kW (current 3
5,000 to 45,000 A) is preferable. When the block size is 100 mm × 100 mm × 400 mm, the input power is 700 to 800 kW (current 15,000 to
25,000 A) is preferred. Also, block size 1
In the case of 50 mm × 150 mm × 400 mm, the input power is 1,100 to 1300 kW (current 40,000 to 50,
000A) is preferred.

At this time, the shorter the time required to reach the graphitization temperature, the better the power efficiency. However, if the arrival time is too early, diffusion of volatile components and graphitization catalyst in the block molded product and sublimation of carbon instantaneously increase, and bumping may occur inside the block molded product. Therefore, the range of time required to reach the graphitization temperature is preferably 1 min to 10 min.
More preferably, it is 2 min to 4 min.

The longer the holding time after reaching the graphitization temperature, the better the graphitization characteristics. Conversely, the shorter the power efficiency, the better. Therefore, the range of the holding time after reaching the graphitization temperature is preferably 1 min to 10 min. More preferably, it is 2 min to 4 min.

If the atmosphere does not contain oxygen, graphitization can be carried out in an atmosphere of an inert gas such as argon or nitrogen and in vacuum. FIG. 11 shows the results of trial manufacture under two kinds of conditions of an argon gas atmosphere and a nitrogen gas atmosphere. In both cases, no difference in the graphitization characteristics was observed, and the graphitization characteristics were good.

The power equipment may use either an AC power supply or a DC power supply. When using an AC power supply,
A power factor improving capacitor is required. Further, when a DC power source is used, the power factor does not decrease, and therefore the power efficiency is improved. Therefore, it is preferable to use a DC power supply for the electric power equipment.

Any of the graphite powders produced in this example are
Various jigs, bearings, seals, crucibles, EDM electrode materials,
It can be used as a relatively high density special carbon graphite material used for heating elements, high temperature vessel linings, nuclear reactors, etc.

According to this embodiment, one block (individual)
It is possible to provide a technique of performing direct heating every time and graphitizing. By making the atmosphere a vacuum or an inert gas, graphitization without packing powder is possible. Further, continuous surface finishing can be further performed to reduce direct labor cost, electric power consumption rate and lead time. For example, the lead time of 30 days in the existing graphite furnace (Acheson furnace) can be shortened to 5 minutes by block continuous graphitization.

As described above, one raw block formed by firing containing the carbon raw material aggregate, the binder, and the catalyst for promoting the graphitization can be directly energized between the electrodes. In the vacuum or in an atmosphere of an inert gas, the original block is directly heated by electric current to form a high density graphitized part inside and a catalyst component precipitate part on the surface part, and An apparatus for manufacturing a graphite block is formed which removes the deposited portion by grinding or the like to form a graphite block.

Further, the raw block formed by firing containing the carbon material aggregate, the binder, and the catalyst for promoting the graphitization is directly pressure-held to the electrode so that it can be energized, and is kept in vacuum or In an atmosphere of an inert gas, and in the absence of packing powder in the surroundings of the raw block and the electrodes, the raw block is directly heated by electrical conduction to form a high density graphitized portion inside,
A graphite block manufacturing apparatus is formed in which a catalyst component precipitation portion is formed on the surface portion, and the catalyst precipitation portion is removed by grinding or the like to form a graphite block.

In addition, a plurality of raw blocks formed by firing containing a carbon material aggregate, a binder, and a catalyst that promotes graphitization are provided in a first vacuum or an inert gas atmosphere space. Carry in and individually carry the original block into the second vacuum or the atmosphere space of the inert gas, individually enable direct current conduction between the electrodes, pressurize and hold, and directly heat the original block directly To form a high-density graphitized portion inside, and to form a catalyst component precipitation portion on the surface portion, and carry out the formed graphitization block individually to a region where the precipitation portion is removed by grinding or the like, An apparatus for manufacturing a graphitized block is formed in which the precipitated portion is deleted in the region to form a graphite block.

The direct holding or energization between the electrodes means that a graphite block manufacturing apparatus for holding or energizing a carbon sheet is arranged on the electrode surface.

Further, the original block formed by containing at least the carbon material aggregate and the binder can be individually energized and directly held between the electrodes, and in a vacuum or an inert gas atmosphere, and A graphite block manufacturing apparatus for forming a graphite block by performing direct current heating to one original block to perform graphitization treatment in the absence of packing powder around the original block and the electrode is configured.

Further, the raw block formed by containing at least the carbon material aggregate and the binder is energized to be directly held between the electrodes, and the raw block is kept in vacuum or in an inert gas atmosphere. The graphite block manufacturing device is configured to form a graphite block by performing direct graphitization by direct current heating by applying electric power concentrated in one original block in the absence of packing material around the block and the electrode. To be done.

Further, a plurality of original blocks containing at least a carbon material aggregate and a binder are carried into a first vacuum or an inert gas atmosphere space, and the original blocks are individually separated into second blocks. It is carried in a vacuum or in an atmosphere of an inert gas, and the original block can be directly energized between the electrodes to hold it under pressure, and the original block and the surroundings of the electrode can be kept in the original state in the absence of packing powder. The graphite block manufacturing apparatus is configured to perform direct current heating by directing electric power concentrated in the blocks to perform graphitization treatment, thereby forming graphite blocks, and individually carrying out the formed graphite blocks.

[0073]

According to the present invention, a single original block is sandwiched between a pair of electrodes to perform graphitization treatment in the absence of packing powder, which results in the above-mentioned undesirable phenomena. It is possible to provide a graphite block manufacturing apparatus capable of canceling the filling of the packing powder that causes the above and generating a graphitization block or a graphite block by direct energization, which can reduce the cost and lead time of the graphitization process. . In particular, the non-use of the packing powder which has been conventionally required is extremely important in that the amount of waste materials is extremely reduced, the uniform flow of current to the original block is formed, and the uniform product is manufactured.
Further, when a carbon material, an aggregate, a binder, and a catalyst that promotes graphitized crystals are used, precipitation of the catalyst components can be formed on the surface of the graphitized block, which facilitates the generation of the graphite block by deletion. It can be carried out. In addition, it is possible to provide a graphitization technique by directly heating a continuous block one by one.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a partial detailed view of FIG.

FIG. 3 is a diagram showing how electric current flows.

FIG. 4 is a diagram showing the state of generation or adhesion of deposits.

FIG. 5 is a diagram showing heating / cooling time.

FIG. 6 is a plan view showing the configuration of a manufacturing apparatus of another embodiment.

7 is an elevation view of FIG.

FIG. 8 is a structural diagram of an electrode portion.

FIG. 9 is a flowchart for starting energization.

FIG. 10 is a diagram showing steps for performing graphitization property evaluation.

FIG. 11 is a test result diagram.

FIG. 12 is a diagram showing a power rising rate and required input power.

[Explanation of symbols]

1 ... Graphite block manufacturing apparatus, 2 ... Graphitization chamber, 3 ...
Raw block, 4 ... Loading space room, 5 ... High temperature heat treatment room, 6 ...
High temperature heat treatment equipment, 7 ... Graphitization block, 8 ... Carrying out space room, 9 ... Surface finishing room, 10 ... Grinding machine, 12, 13 ... Vacuum pump, 15, 33 ... Truck, 16, 31 ... Conveyor, 2
1, 22 ... Electrodes, 23, 24 ... Pressurizing device, 25 ... Conducting device, 26 ... Computer device, 27 ... Reflector (including carbon cylinder), 32 ... Graphite block.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3K058 AA34 AA86 BA19 FA02 FA04                 4G132 AA02 AA04 AA07 AA09 AA14                       AA18 AA32 AA46 AA61 AA62                       AA65 AA75 BA02 BA07 BA08                       BA13 BA26 GA25 GA38 GA43                 4G146 AA02 AB05 BA02 BA22 BA27                       BB03 BC06 BC44 BC45 BC46                       CB02 DA32 DA35

Claims (8)

[Claims] 1. A graphite block manufacturing apparatus for graphitizing a raw block which is a graphitizable carbon compact by high temperature heat treatment, and a pair of electrodes for energizing and holding a single raw block, and a vacuum forming apparatus. Alternatively, an inert gas charging device, a pressurizing device that pressurizes the held original block in the electrode direction through the electrode, and an energizing device that energizes the electrode, and the surroundings of the electrode and the original block are provided. An apparatus for producing a graphite block, comprising a high-temperature heat treatment apparatus for performing graphitization treatment by heat itself generated in an original block in the absence of a packing powder. 2. A graphite block manufacturing apparatus for graphitizing a raw block, which is a graphitizable carbon compact, by high-temperature heat treatment, and a pair of electrodes for energizing and holding a single raw block, and a vacuum forming apparatus. Alternatively, an inert gas charging device, a pressurizing device for pressurizing the held original block in the electrode direction through the electrode, and an energizing device for energizing the electrode are provided, and the surroundings of the electrode and the original block are provided. An apparatus for producing a graphite block, comprising a high-temperature heat treatment apparatus that performs graphitization treatment by the heat itself generated in the original block as a space state. 3. A graphite block manufacturing apparatus for performing graphitization by high-temperature heat treatment of an original block which is a graphitizable carbon compact, and a vacuum forming apparatus, and a pair of electrodes for energizing and holding a single original block. Alternatively, an inert gas charging device, a pressurizing device for pressurizing the held original block in the electrode direction through the electrode, and an energizing device for energizing the electrode are provided and concentrated from the electrode to the original block. An apparatus for producing a graphite block, comprising a high-temperature heat treatment apparatus for performing graphitization treatment by the heat itself generated in an original block by applying electricity. 4. A graphite block manufacturing apparatus for performing graphitization by high-temperature heat treatment of a raw block which is a graphitizable carbon compact containing a catalyst for promoting graphitization. A pair of electrodes, a vacuum forming device or an inert gas charging device, a pressurizing device for pressurizing the held original block in the electrode direction through the electrodes, and an energizing device for energizing the electrodes. A high-temperature heat treatment device, and a surface finishing device for performing surface finishing by grinding etc. on the catalyst component precipitation portion formed on the surface portion of the high-density graphitized portion inside by the graphitization treatment by the high-temperature heat treatment device. An apparatus for manufacturing a graphite block, which is characterized in that 5. A graphite block manufacturing apparatus for performing graphitization by high-temperature heat treatment of a raw block formed by firing containing a carbon material aggregate and a binder, wherein a single raw block is energized and held. A pair of electrodes, a vacuum forming device or an inert gas charging device, a pressurizing device for pressurizing the held original block in the electrode direction through the electrodes, and an energizing device for energizing the electrodes. A high-temperature heat treatment device for performing graphitization treatment by heat itself generated in the original block by collecting current concentrated in the original block through the electrode in the absence of packing powder around the electrode and the original block; A vacuum forming apparatus or an inert gas charging apparatus, and a transfer space chamber including a transfer apparatus for transferring the loaded original block to the high temperature heat treatment apparatus. Apparatus for producing a graphite block. 6. The high temperature heat treatment apparatus according to claim 5, wherein the high temperature heat treatment apparatus is located adjacent to the high temperature heat treatment apparatus on the other side of the transfer space chamber so as to be flush with the high temperature heat treatment apparatus. An apparatus for manufacturing a graphite block, characterized in that a surface finishing chamber equipped with a surface finishing device is provided by grinding the catalyst component precipitation portion formed on the surface portion of the high-density graphitized portion inside by the graphitization treatment by . 7. A graphite block manufacturing apparatus according to claim 1, wherein a heat reflecting plate is provided around the original block with a space interposed therebetween. 8. A graphite block manufacturing apparatus according to claim 1, wherein a carbon sheet is provided between the electrode and the original block.