JP4677667B2 - Graphitization apparatus and graphitization method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a graphitization apparatus and a graphitization method for producing a graphite powder, and more particularly to a graphitization apparatus and a graphitization method for producing a graphite powder by heating carbon powder particles.
[0002]
[Prior art]
In general, as a method for industrially producing graphite powder, there is known a method of graphitizing carbon powder (raw material powder) such as carbon powder by, for example, heat treatment at about 3000 ° C. or more in an inert atmosphere. It has been. As an apparatus for graphitizing in this way, an Atchison furnace is used in which the raw material powder is indirectly heated and graphitized by Joule heat generated by energizing carbon powder particles.
[0003]
[Problems to be solved by the invention]
However, the conventional graphitization apparatus and the graphitization method as described above have the following problems.
Since heating to the carbon powder is performed by energization, the carbon powder needs to be conductive. However, although carbon powder particles exhibit conductivity at a temperature of 1000 to 1200 ° C., they are supplied at a temperature of 650 ° C. or less, so that there is a problem that sufficient Joule heat necessary for heating cannot be obtained.
[0004]
In addition, since carbon powder is heated by being energized by the electrode in the furnace, gas such as methane and hydrogen is generated around the electrode, and the state around the electrode (bulk specific gravity, pressing force, electrical conductivity, heat conduction) There was also a problem that stable operation (electric heating control) could not be performed.
[0005]
The present invention has been made in view of the above points, and an object of the present invention is to provide a graphitization apparatus and a graphitization method capable of obtaining sufficient Joule heat and capable of performing stable operation.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention employs the following configuration.
The graphitization apparatus of the present invention is a graphitization apparatus having a graphitization furnace for heating and graphitizing the supplied carbon powder particles, and preliminarily heating the carbon powder particles in the graphitization furnace. A heating device is provided, and the preheating device has a tubular body extending in the vertical direction and a plurality of heating elements extending in the horizontal direction and disposed in the internal space of the tubular body. The heating element group is formed by a plurality of the heating elements arranged in parallel with a space in the horizontal direction, and the heating element group is provided in a plurality of stages along the vertical direction, and the adjacent heating stage The extending directions of the heating elements are arranged so as to intersect with each other in plan view, and a preheating region is formed in a gap between the plurality of heating elements .
As the heating element group, a configuration can be adopted in which the extending directions of the heating elements are arranged in a lattice pattern in a perpendicular manner in adjacent stages.
[0007]
Therefore, in the graphitization apparatus of the present invention, excess gas can be extracted from the carbon powder in advance by preheating. Therefore, the amount of gas generated from the carbon powder particles in the graphitization furnace can be suppressed, and stable operation becomes possible. Moreover, since it becomes possible to give electroconductivity to a carbon granular material by adjusting preheating temperature, sufficient Joule heat can be obtained in a graphitization furnace.
[0008]
The graphitization apparatus according to claim 2 is the graphitization apparatus according to claim 1, wherein the preheating apparatus preheats the carbon powder to a temperature of 700 ° C or higher and 1500 ° C or lower, and the graphite. It is provided in the upper part of a blast furnace.
[0009]
Therefore, in the graphitization apparatus of the present invention, excess gas can be generated in advance by heating the carbon powder at a temperature of 700 ° C. or higher. Moreover, by heating the carbon powder at a temperature of 1500 ° C. or less, an inexpensive refractory material such as alumina can be used, and the equipment cost can be suppressed. Moreover, in the graphitization apparatus of the present invention, the preheated carbon powder can be continuously supplied to the graphitization furnace by its own weight by providing a preheating device in the upper part of the graphitization furnace.
[0010]
The graphitization apparatus according to claim 3 is the graphitization apparatus according to claim 1 or 2, wherein the graphitization region of the graphitization furnace and the heating region of the preheating device are arranged adjacent to each other. To do.
[0011]
Therefore, in the graphitization apparatus of the present invention, the time required for the preheated carbon particles to reach the graphitization region can be minimized, and the temperature drop of the carbon particles can be suppressed. Further, waste heat generated in the graphitization region or heat due to heat conduction can be easily used in the heating region.
[0012]
The graphitization apparatus according to claim 4 is the graphitization apparatus according to any one of claims 1 to 3, wherein the preheating device is provided with an exhaust unit that exhausts the gas generated from the carbon powder. It is characterized by this.
[0013]
Therefore, in the graphitization apparatus of the present invention, the gas generated at the time of preheating or the gas generated in the graphitization furnace can be discharged.
[0014]
The graphitization method of the present invention is a graphitization method in which carbon powder is supplied to a graphitization furnace and then heated to graphitize, and is arranged extending in the vertical direction. A tube body and a plurality of heating elements extending in the horizontal direction and arranged in the internal space of the tube body are provided, and a heating element group is formed by the plurality of heating elements arranged in parallel at intervals in the horizontal direction. The heating element group is provided in a plurality of stages along the vertical direction, and the extending direction of the heating elements is arranged so as to intersect in a plan view in adjacent stages, and is formed in a gap between the plurality of heating elements. A preheating region is formed, and the carbon powder particles are preheated in the preheating region .
[0015]
Therefore, in the graphitization method of the present invention, excess gas can be extracted from the carbon powder in advance by preheating. Therefore, the amount of gas generated from the carbon powder particles in the graphitization furnace can be suppressed, and stable operation becomes possible. Moreover, since it becomes possible to give electroconductivity to a carbon granular material by adjusting preheating temperature, sufficient Joule heat can be obtained in a graphitization furnace. Moreover, in the graphitization method of this invention, an excess gas can be previously generated by heating a carbon granular material at the temperature of 700 degreeC or more. Moreover, by heating the carbon powder at a temperature of 1500 ° C. or less, an inexpensive refractory material such as alumina can be used, and the equipment cost can be suppressed.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of a graphitization apparatus and a graphitization method of the present invention will be described with reference to FIGS. 1 and 2.
FIG. 1 is a cross-sectional view showing a graphitization apparatus 1 according to the present invention. This graphitization apparatus 1 is provided in a graphitization furnace (graphitization electric furnace) 2 having a vertical structure, a supply apparatus 3 for supplying carbon powder as raw material powder to the graphitization furnace 2, and the graphitization furnace 2 The preheating device 4 is mainly used.
[0017]
A graphite powder recovery means 9 is connected to the furnace body 5 of the graphitization furnace 2 via a tubular member 8 at the bottom, and electrodes 6 and 7 are attached to opposing side walls, respectively. The electrodes 6 and 7 are connected to a direct current or alternating current power source (not shown). A space between the electrodes 6 and 7 serves as a graphitization region 10 for graphitizing the carbon powder. Further, the furnace body 5 is formed so as to be narrowed as the shape of the lower part goes downward in order to increase the cooling efficiency.
[0018]
The supply device 3 is generally composed of receiving hoppers 11 and 12 and a feeder 13. Connected to the receiving hopper 11 are a supply pipe 14 to which carbon powder is supplied by a supply pump or the like, and a pipe 16 having a valve 15 interposed and connected to a bag filter. A receiving hopper 12 is connected to the lower side of the receiving hopper 11 via a valve 17. The receiving hopper 12 is connected with a pipe 19 provided with a valve 18 and supplying argon gas, and a pipe 33 having one end connected to the intake pipe 20 via the valve 21. A feeder 13 is connected via 22.
[0019]
The preheating device 4 is provided at the upper part of the graphitization furnace 2, a preheating hopper 23 that is integrally attached to the upper end of the furnace body 5, and a heating element 24 that is suspended in the preheating hopper 23 in the vertical direction. And the main constituent. The preheating hopper 23 is loaded with a heat-insulating blanket 25 with a gap 27 between the preheating hopper 23 and the top plate 23a. An intake pipe (exhaust part) 20 and an exhaust pipe (exhaust part) 26 are connected to the top plate 23 a so as to open in the gap 27. A suction pump (not shown) such as a rotary pump is connected to the intake pipe 20.
[0020]
At the center of the blanket 25, a graphite tube 29 is fixed along a vertical direction via a cylindrical heat insulating material 28. The lower end of the internal space of the graphite tube 29 communicates with the furnace body 5, and the upper end is It communicates with the gap 27. As shown in FIG. 2, a plurality of (four in the figure) heating elements 24 are annularly arranged inside the graphite tube 29 so as to be spaced apart from the inner peripheral surface. The heating element 24 is obtained by enclosing a heater element 31 in a quartz tube 30. A space between the inner peripheral surface of the graphite tube 29 and the heating element 24 (quartz tube 30) becomes a heating region 32 for the coal bed granular material. As shown in FIG. 1, the heating region 32 is disposed adjacent to and above the graphitization region 10 in the furnace body 5. In addition, carbon powder particles are supplied from the feeder 13 above the heating region 32.
[0021]
The heater element 31 is arranged at a distance of 100 mm or more from the upper ends of the electrodes 6 and 7 of the graphitization furnace 2 and is not affected by bubbling caused by the energized heating gas (change in pressing force, bulk specific gravity, etc.). ing.
[0022]
The procedure for graphitizing carbon powder particles with the graphitization apparatus having the above-described configuration will be described.
First, the carbon powder 11 is supplied to the receiving hopper 11 through the supply pipe 14 with the valve 15 opened and the valve 17 closed. Next, the valve 17 is opened with the valve 22 closed, and the carbon powder is transferred to the receiving hopper 12. Then, the valves 18 and 21 are opened with the valve 17 closed, and the inside of the receiving hopper 12 is sucked through the pipe 33 and the intake pipe 20, and argon gas is introduced from the pipe 19. Thereby, the air in the receiving hopper 12 is replaced with argon gas.
[0023]
Subsequently, the valves 18 and 21 are closed and the valve 22 is opened, and the carbon powder is continuously (or periodically) supplied above the heating region 32 by the feeder 13. The supplied carbon powder particles are gradually heated by the heating element 24 while moving downward in the heating region 32 by its own weight and supply pressure. Thus, before reaching the graphitization region 10, the carbon powder is preheated to a temperature of 700 to 1500 ° C. In particular, in the present embodiment, since the heating region 32 is disposed adjacent to the upper portion of the graphitization region 10, the heat generated in the graphitization region 10 is transmitted by heat conduction or radiation, and the carbon particles are efficiently formed. Can be heated.
[0024]
Here, by heating the carbon particles to 700 ° C. or higher, it is possible to generate excess gas such as methane and hydrogen from the carbon particles. The generated gas is exhausted from the gap 27 through the intake pipe 20 (and the exhaust pipe 26). Moreover, even if it heats a carbon granular material, inexpensive refractory materials, such as an alumina type | system | group, can be used by restraining to 1500 degrees C or less, and installation cost can be suppressed.
[0025]
And by energizing between the electrodes 6 and 7 (for example, 50V, 1000A), the carbon particles themselves generate heat by Joule heat according to the specific resistance to form a graphitized region 10 of about 2500 ° C to 3500 ° C. The carbon powder in this region is graphitized. In addition, since the carbon granular material thrown into the furnace main body 5 is preheated to the temperature which has electroconductivity with the preheating apparatus 4, it can energize and generate | occur | produce without trouble.
[0026]
Carbon powder properly graphitized in the graphitization region 10, that is, graphite powder heat-treated in a desired temperature region, is sent from the inlet 8 a of the tubular member 8 to the recovery means 9 and recovered. In addition, the position of this inlet 8a is arrange | positioned directly under the graphitization area | region 10 in consideration of the angle of repose of a carbon granular material for the purpose of taking out graphite powder efficiently.
[0027]
In the graphitization apparatus and the graphitization method of the present embodiment, the carbon powder is preheated and degassed before being put into the furnace body 5, and thus generated when graphitizing in the furnace body 5. Gas to be reduced. Therefore, it is possible to prevent the state around the electrodes 6 and 7 from being changed due to gas generation, and a stable operation can be performed. Moreover, since the degassing can be reliably performed by preheating the carbon powder particles to 700 ° C. or higher, more stable operation can be continuously performed. Moreover, since the intake pipe 20 and the exhaust pipe 26 are connected to the preheating device 4, the gas generated by the preheating (and graphitization) can be removed reliably and easily, and the gas is contained in the furnace body 5. Therefore, it is possible to prevent the disturbance of the state around the electrode. In addition, by preheating, the carbon powder can be made to exhibit conductivity, and sufficient Joule heat necessary for heating in the furnace body 5 can be obtained.
[0028]
Furthermore, in the present embodiment, since the heating region 32 and the graphitized region 10 are disposed adjacent to each other, the heat generated in the graphitized region 10 can be used for preheating by heat conduction or radiation, and administration. It is also possible to effectively use the energy and reduce the operating cost of the device. Further, since these regions 10 and 32 are adjacent to each other, the effect that the preheated carbon powder particles can be continuously charged into the furnace main body 5 without causing a temperature decrease is also obtained.
[0029]
Moreover, in the present embodiment, since the preheating device 4 is provided in the upper part of the graphitization furnace 2, the carbon powder can be preheated while moving under its own weight and supply pressure. It is no longer necessary to provide a separate mechanism for guiding the inside of the furnace body 5, which can contribute to downsizing and cost reduction of the apparatus. Moreover, in this Embodiment, cheap refractory materials, such as an alumina type | system | group, can be used by making preheating with respect to a carbon granular material 1500 degrees C or less, and can also suppress installation cost.
[0030]
FIG. 3 and FIG. 4 are diagrams showing a second embodiment of the graphitization apparatus and the graphitization method of the present invention. In these drawings, the same components as those of the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted. The difference between the second embodiment and the first embodiment is the configuration of the preheating region.
[0031]
As shown in FIG. 3, a heat insulating material 28 is fitted and fixed along the vertical direction at the center of the blanket 25. As shown in FIG. 4, the heat insulating material 28 has a square shape in cross section, and a graphite tube 29 is fixed along the vertical direction with a gap left and right in the center of the inner space 28 a. ing. The graphite tube 29 has a rectangular shape in cross section, and its internal space is a heating region 32 that communicates with the graphitization region 10 in the furnace body 5. At the upper end of the graphite tube 29, there is provided an intake port 29a that expands upward and opens into the gap 27 (see FIG. 3). The intake port 29a is disposed directly below the input port 34 into which the carbon powder particles are input.
[0032]
Further, in the internal space 28 a of the heat insulating material 28, plate-like heating elements 24, 24 are disposed along the vertical direction with a space between the heat insulating material 28 and the graphite tube 29 with the graphite tube 29 interposed therebetween. Other configurations are almost the same as those in the first embodiment.
[0033]
In the graphitization apparatus 1 of the present embodiment, the carbon powder particles introduced from the introduction port 34 are introduced into the heating region 32 of the graphite tube 29 from the intake port 29a. Since the carbon powder particles are gradually preheated by the heat generated by the heating elements 24 and 24 through the graphite tube 29 while moving downward in the heating region 32 with its own weight and supply pressure, The same effect as the embodiment can be obtained.
[0034]
FIG. 5 is a diagram showing a third embodiment of the graphitization apparatus and the graphitization method of the present invention. In this figure, the same reference numerals are given to the same elements as those of the first embodiment shown in FIGS. 1 and 2, and the description thereof is omitted. The difference between the third embodiment and the first embodiment is the configuration of the heating element and the exhaust port.
[0035]
As shown in FIG. 5, a cylindrical heat insulating material 28 is disposed along the vertical direction in the preheating hopper 23 of the preheating device 4, and a graphite tube 29 is fixed to the inner peripheral surface of the heat insulating material 28. ing. In the heating region 32, the heat generators 24 extending in the horizontal direction are arranged in a plurality of stages (six stages in the figure) along the vertical direction in the heat insulating material 28 and the graphite tube 29.
[0036]
As shown in FIG. 6, both the heat insulating material 28 and the graphite tube 29 have a rectangular shape in cross section, and the heating element 24 is arranged in parallel with each side of the rectangular shape. More specifically, the heating elements 24 are arranged in a lattice shape in plan view so that a plurality of (five in the figure) parallel to each other at a certain interval in each step and adjacent steps are orthogonal to each other. Yes. A gap between the plurality of heating elements 24 is a heating region 32.
[0037]
The lower end of the graphite tube 29 is exposed in the furnace body 5, and the upper end is reduced in diameter as it goes upward and is connected to the exhaust pipe 26 (or the intake pipe 20). The inlet 34 through which the carbon powder particles are introduced is connected to the reduced diameter portion via the feeder 13.
[0038]
In the graphitization apparatus 1 having the above-described configuration, the carbon powder particles introduced from the introduction port 34 are introduced into the graphite tube 29 and moved downward by its own weight and supply pressure in the heating region 32 between the heating elements 24. After preheating, it is graphitized in the graphitization furnace 2. Further, the gas generated in the preheating step rises upward and is discharged from the exhaust pipe 26 (or the intake pipe 20) as it is.
[0039]
In the graphitization apparatus and the graphitization method of the present embodiment, in addition to obtaining the same effect as in the first embodiment, the contact area of the carbon powder particles with respect to the heating element 24 is increased. The carbon powder can be efficiently preheated. In addition, since the exhaust pipe 26 (or the intake pipe 20) is provided directly above the heating region 32, the generated excess gas can be easily released, and degassing can be executed more quickly.
[0040]
The preheating device according to the present invention is not limited to the configuration of the above embodiment. For example, the carbon powder supplied from the supply device 3 is preheated in the kiln furnace 35 and then graphitized. It is good also as a structure graphitized by 2. In this case, it is preferable to provide an exhaust pipe 36 as an exhaust part for discharging the gas generated by the preliminary heating in the kiln furnace 35.
[0041]
【The invention's effect】
As described above, the graphitization apparatus according to claim 1 is configured such that the preheating device preheats the carbon powder particles.
As a result, in this graphitization apparatus, it is possible to continuously perform a stable operation by preventing the state around the electrodes from being changed due to gas generation, and also to heat the carbon particles by developing conductivity. There is an effect that sufficient Joule heat necessary for the above can be obtained.
[0042]
The graphitization apparatus according to claim 2 is configured such that the preheating device preheats the carbon powder to a temperature of 700 ° C. or more and 1500 ° C. or less and is provided at the upper part of the graphitization furnace.
As a result, in this graphitization apparatus, degassing can be reliably performed, more stable operation can be continuously performed, and conductive carbon powder that can be continuously directly energized in the graphitization furnace. The effect that the granule is supplied and the running cost can be reduced is obtained. In addition, the carbon powder can be preheated while moving under its own weight, and there is no need to provide a separate mechanism for guiding the carbon powder to the graphitization furnace, contributing to downsizing and cost reduction of the apparatus. An effect is also obtained.
[0043]
The graphitization apparatus according to claim 3 is configured such that the graphitization region and the heating region are disposed adjacent to each other.
Thereby, in this graphitization apparatus, the heat generated in the graphitization region can be used also in the preheating, the effective use of the administered energy is realized, the operation cost of the apparatus can be reduced, and the temperature is lowered. The effect that the preheated carbon powder can be continuously charged into the graphitization furnace is obtained.
[0044]
The graphitization apparatus according to claim 4 is provided with an exhaust part for exhausting the gas generated from the carbon powder.
Thereby, in this graphitization apparatus, it is possible to prevent the gas from entering the graphitization furnace and becoming a disturbance of the state around the electrode.
[0045]
The graphitization method according to claim 5 is a procedure in which the carbon powder is preheated to a temperature of 700 ° C. or higher and 1500 ° C. or lower and supplied to the graphitization furnace.
As a result, in this graphitization method, stable operation can be continuously performed by preventing the change of the state around the electrode due to gas generation, and the carbon particles can be made conductive and heated. There is an effect that sufficient Joule heat necessary for the above can be obtained. Further, it is possible to obtain an effect of reducing the running cost by supplying carbon particles having conductivity that can be directly and continuously energized to the graphitization furnace.
[Brief description of the drawings]
FIG. 1 is a diagram showing a first embodiment of the present invention and is a schematic configuration diagram of a graphitization apparatus having a preheating device.
FIG. 2 is a cross-sectional view of a main part of the preheating device.
FIG. 3 is a schematic configuration diagram of a graphitization apparatus according to a second embodiment of the present invention.
4 is a cross-sectional view of a main part of the preheating device in FIG. 3. FIG.
FIG. 5 is a schematic configuration diagram of a graphitization apparatus according to a third embodiment of the present invention.
6 is a cross-sectional view of a main part of the preheating device in FIG.
FIG. 7 is a schematic configuration diagram of a preheating device according to another embodiment.
[Explanation of symbols]
1 Graphitization equipment 2 Graphitization furnace (graphitization electric furnace)
4 Preheating device 10 Graphitization region 20 Intake pipe (exhaust section)
26 Exhaust pipe (exhaust section)

Claims (8)

A graphitization apparatus having a graphitization furnace for heating and graphitizing supplied carbon particles,
The graphitization furnace is provided with a preheating device for preheating the carbon powder particles ,
The preheating device has a tubular body extending in the vertical direction, and a plurality of heating elements extending in the horizontal direction and disposed in the internal space of the tubular body,
A heating element group is formed by a plurality of the heating elements arranged parallel to each other in the horizontal direction,
The heating element group is provided in a plurality of stages along the vertical direction, and the extending directions of the heating elements are arranged so as to intersect in a plan view at adjacent stages,
A graphitization apparatus, wherein a preheating region is formed in a gap between the plurality of heating elements . The graphitization apparatus according to claim 1, wherein
The graphitization apparatus, wherein the heating element groups are arranged in a grid pattern in plan view in which the extending directions of the heating elements are orthogonal to each other at adjacent stages. The graphitization apparatus according to claim 1 or 2 ,
The preheating apparatus preliminarily heats the carbon powder particles to a temperature of 700 ° C. or higher and 1500 ° C. or lower, and is provided in an upper portion of the graphitization furnace. In the graphitization apparatus according to any one of claims 1 to 3 ,
A graphitization apparatus, wherein a graphitization region of the graphitization furnace and a heating region of the preheating device are disposed adjacent to each other. In the graphitization apparatus according to any one of claims 1 to 4 ,
The graphitization apparatus, wherein the preheating device is provided with an exhaust unit for exhausting a gas generated from the carbon powder. A graphitization method of heating and graphitizing the carbon powder after supplying the carbon powder to a graphitization furnace,
A tube body that extends in the vertical direction and a plurality of heating elements that extend in the horizontal direction and are disposed in the internal space of the tube body are provided.
A heating element group is formed by the plurality of heating elements arranged parallel to each other in the horizontal direction,
The heating element group is provided in a plurality of stages along the vertical direction, and the heating elements are arranged in adjacent stages so that the extending directions of the heating elements intersect in a plan view, and a preheating region is provided in a gap between the plurality of heating elements. Form the
A graphitization method , wherein the carbon powder particles are preheated in the preheating region . The graphitization method according to claim 6, wherein
The graphitization method, wherein the heating element groups are arranged in a grid pattern in a plan view in which extending directions of the heating elements are orthogonal to each other at adjacent stages. The graphitization method according to claim 6 or 7,
A graphitization method, wherein the carbon powder is supplied to the graphitization furnace in a state of being preheated to a temperature of 700 ° C. or higher and 1500 ° C. or lower.

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