JPH03183608A - Device for producing graphite powder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a graphite powder manufacturing apparatus that heats carbon powder to graphitize it.

"Prior Art and its Problems" As is well known, carbon products are widely used in various fields, and demand for graphite products has particularly increased in recent years.

By the way, graphite powder, which is the material of graphite products, is made by heating amorphous carbon powder at 2,000°C to 3.5°C. It is produced by graphitizing carbon powder by heating it to a high temperature of about OOO'C, but to date no effective graphite production equipment that can continuously graphitize carbon powder has been provided. Conventionally, graphite production has been carried out using a batch/batch process, but the batch-type graphitization process that has been commonly used requires a cycle time of more than ten days, resulting in extremely low productivity. This is not good, and therefore it is difficult to reduce costs.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a graphite powder manufacturing apparatus that can continuously graphitize carbon powder.

"Means for Solving the Problems" The present invention is a graphite powder manufacturing apparatus that graphitizes carbon powder by heating it to a high temperature, and includes a furnace body and a graphite powder manufacturing apparatus that is provided vertically penetrating the furnace body. a mold having a spiral groove-shaped passage formed by a screw provided therein; and a heating means provided inside the furnace body for heating the mold from the outside; It is characterized in that the carbon powder introduced into the inside is lowered in the passage and heated through the mold by the heating means, thereby being graphitized and taken out from the lower end of the mold. Further, it is desirable to include a gas blowing means for blowing gas into the passageway through a gas blowing pipe provided inside the mold.

"Function" The graphite powder manufacturing apparatus of the present invention continuously charges carbon powder as a raw material from the upper end of a mold, allows the carbon powder to fall under its own weight, and continuously takes it out from the lower end of the mold. By heating the mold to a high temperature using a heating means, the carbon powder passing through the mold is heated and graphitized. and,
By providing a screw in the mold, the path through which the powder descends is formed into a spiral groove, so that the powder descends while swirling within the mold, and as a result, the powder is naturally agitated and its drift is prevented. In addition, the powder's own weight is supported by the screw to prevent the shelf-hanging phenomenon from occurring, and due to the heat transfer effect from the mold to the screw, the screw itself becomes hot and the powder is transferred not only by the mold but also by the screw. is also heated.

"Embodiment" An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the overall schematic structure of the graphite powder manufacturing apparatus of this embodiment, and the reference numeral 1 in the figure is a furnace body.

Inside the furnace body 1, a preheating chamber 2, a heating chamber 3, and a precooling chamber 4 each formed of a heat insulating material are successively arranged from the top in that order. is provided. This furnace body 1 is configured such that its internal air can be replaced with an atmospheric gas (generally an inert gas such as nitrogen or argon).

A charging chamber 6 connected to the preheating chamber 2 is provided in the upper part of the furnace body 1, and a charging hopper 7 is further provided above the charging chamber 6. A supply pipe 8 for carbon powder C, which is a raw material, is connected to the charging hopper 7, and the charging hopper 7 and charging chamber 6 are connected to each other.
A bell-shaped valve 9 is provided between the two and can be moved up and down by a drive device 10.

On the other hand, a cooling chamber 11 connected to the precooling chamber 4 is provided in the lower part of the furnace body 1, and a discharge hopper 12 is provided below the cooling chamber 11, and a funnel-shaped discharge port 13 is provided between them. At the same time, a screw feeder 14 for taking out graphite powder B as a product is attached to the lower part of the discharge hopper 12. Further, the wall surface of the cooling chamber 11 has a water-cooled structure, and cooling fins (not shown) are provided inside the cooling chamber 11 to forcibly cool the graphite powder B stored inside.

At the center of the furnace body 1, there is a long cylindrical mold that vertically passes through the furnace body 1 and has an upper end open to the charging chamber 6 and a lower end open to the cooling chamber 11. 15
is provided. This mold 15 has a bottom shape made of graphite, and the part located inside the heating chamber 3 is heated by the heater 5 located outside of the mold 15, so that the inside of the heating chamber 3 is heated. The temperature of the intermediate portion located is the temperature required to graphitize the carbon powder C, for example 2. It is heated to a temperature of about OOO'O to 3,000°C. When the part of the mold 15 located inside the heating chamber 3 is heated to the above-mentioned temperature, the mold 15 is heated not only inside the heating chamber 3 but also to the parts above and below it, i.e., by its own excellent heat transfer action. Although the portions located in the preheating chamber 2 and the precooling chamber 4 are also high in temperature, the temperature gradually decreases toward the upper and lower ends of the mold 15.

Furthermore, a core 16 is provided within the mold 15. The core 16 is molded from graphite like the mold 15, and is made of graphite.
The length extends from the upper end to the lower end of the cooling chamber 11.
The lower end is supported by a support portion 17 provided inside.

This core 16 has a plurality of (four in the illustrated example) screws 19 formed around a cylindrical core material 18, and the core 16 is arranged inside the mold 15. A plurality of (four in the illustrated example) spiral groove-shaped powder passages 20 are formed in the mold 15, and the raw material powder C charged therein from the upper end of the mold 15 is formed inside the mold 15.
will descend within each passageway 20 while spirally turning around the core 1818.

Note that if the pitch of each screw 19 is set large, the descending speed of the powder C increases, and if the pitch is set small, the descending speed becomes small. However, the inclination angle of the screw 19 with respect to the horizontal plane is such that the powder C does not stay on the screw 19 and its descent is inhibited.
It is necessary to keep the angle of repose at least equal to (generally about 45 degrees).

Further, the above-mentioned apparatus is equipped with a gas blowing means 21 for blowing atmospheric gas into the passage 20. The gas blowing means includes two gas blowing pipes 21a and 21b incorporated in the core material 18 of the core 16, and a gas blowing pipe for blowing gas toward each passage 20 from the gas blowing pipes 21&, 21b. It consists of a pipe 22 (see FIGS. 2 and 3) and a gas supply source device 21c provided outside the furnace and connected to the gas blowing pipes 21a and 21b.

The gas blowing pipes 22 described above are provided at predetermined intervals along the longitudinal direction of the core 16, and are connected to one gas blowing pipe 21a, as shown in FIGS. 2 and 3. The position of the Suita pipe 22 and the position of the blow-off pipe 22 connected to the other gas blow-in pipe 21b are made to be different from each other.

Further, the gas supply source device 21e includes two gas blowing pipes 21! , 21b, so that the gas is alternately blown into the passage 20 from the gas blowing pipes 22 provided at different positions. Further, the gas supply source device 21c is capable of changing the gas blowing pressure in a pulsed manner at a predetermined period.

The gas blowing means 21 described above is connected to the passage 20 as described above.
By blowing gas into the passage 20, the gas pressure prevents the powder C from hanging in the passage 20, and
This is to eliminate the problem of shelf hanging if it occurs.

Note that if gas is supplied to both gas blowing pipes 21a and 21b at the same time and gas is blown out from all gas Suita pipes 22 at the same time, the gas pressure in each passage 20 will only increase evenly. There is no pressure difference between the top and bottom of the section, and therefore it is difficult to destroy the shelf suspension. By blowing out
Since pressure can be applied alternately from above and below the shelf hanging part, shelf hanging can be easily eliminated. In addition, by intermittently blowing gas or changing the gas pressure in a pulsed manner to increase or decrease the intensity, shelf hanging can be eliminated even more effectively.

Based on the above configuration, this graphite powder manufacturing apparatus is capable of manufacturing graphite powder B by continuously graphitizing carbon powder C, which is a raw material.

That is, carbon powder C, which is a raw material, is placed in each passage 20 in advance.
After filling the cooling chamber 11 and the discharge hopper 12 and heating the mold 15 with the heater 5, carbon powder C is continuously supplied to the charging hopper 7 through the supply pipe 8, and the valve 9 is opened at predetermined intervals. By pushing down, a predetermined amount of carbon powder C is charged from the charging hopper 7 into the charging chamber 6, and at the same time, the powder filled in the discharge hopper 12 is taken out by the screw feeder 14. As a result, the carbon powder C flows down from the charging chamber 6 into each passage 20, and gradually descends inside the passage 20 due to its own weight.

The carbon powder C descending in this way is preheated by the mold 15 while passing through the preheating chamber 2, and further heated to the temperature necessary for graphitization while passing through the heating chamber 3. It is heated and graphitized to produce graphite powder B.

The graphite powder B produced as described above further descends and is gradually cooled while passing through the pre-cooling chamber 4, flows down from the lower end of the mold 15 into the cooling chamber 11, where it stays for a predetermined period of time, and is sufficiently cooled. After being forcibly cooled, it is discharged through the discharge port 13 into the discharge hopper 12, from which it is taken out in predetermined amounts by the screw feeder 14.

In the graphitization process described above, it takes about 3 hours from the time the carbon powder C flows into the mold 15 until it passes through the preheating chamber 2 and the heating chamber 3. The powder (carbon powder C as a raw material and graphite powder B as a product) is heated so that the time it takes to flow into the cooling chamber 11 is about 3 hours and the cooling time in the cooling chamber 11 is about 100 hours.
It is preferable to set the descending speed of the carbon powder C into the charging chamber 6 by setting the pitch of the screw 19 in advance so as to obtain the desired descending speed.
The charging amount and the amount of graphite powder B taken out from the discharge hopper 12 may be adjusted.

As explained above, this production equipment is capable of graphitizing carbon powder C continuously and in an extremely short time compared to conventional batch-type systems, thus greatly improving production efficiency. can be improved.

In the above device, a core 16 having a screw 19 is provided in the mold 15, and a passage 20 through which the powder descends is provided.
Since these are spirally grooved, the powder descends while rotating around the core material 18. Therefore, in the case where such a core 16 is not provided, there is a concern about poor heat transfer to the carbon powder C. It is possible to effectively prevent the occurrence of the drifting, drifting, and shelf-hanging phenomena.

That is, the carbon powder C, which is a raw material, has extremely poor thermal conductivity, and if it is simply dropped inside the cylindrical mold 15, the powder C will not be stirred, and therefore will not be in contact with the inner surface of the mold 15. If the powder C is only heated and descends from the center side, it may not be sufficiently heated, but in the device of the above embodiment, the powder C descends while rotating around the core material 18. As a result, all of the powder C is evenly heated and graphitized without fail.

In addition, the outer peripheral end surface of the screw 19 comes into contact with or sufficiently close to the inner surface of the mold 15.Secondly, sufficient heat is transferred from the mold 15 to the screw 19,
As a result, the temperatures of the screw 19 and the core material 18 naturally increase. Therefore, carbon powder C is molded into mold 1.
5, the carbon powder C is heated not only from the outside by the screw 19 of the core 16 and the core material 18, but also from the inside by the screw 19 of the core 16 and the core material 18. This makes it possible to significantly improve heating efficiency.

In addition, in the case where the core 16 is not provided, the descending speed is high at the center of the mold 15, and the descending speed is high at the portion along the inner surface of the mold 15 due to the frictional resistance generated between the inner surface of the mold 15 and the inner surface of the mold 15. In other words, it is unavoidable that the descending speed becomes uneven at each position in the radial direction and a significant drift occurs, but in the above device, the inside of the mold 15 is formed by four spiral groove-like small cross-section passages 20 by the screw 19. Due to the partitioning, drifting of currents is naturally sufficiently suppressed.

Furthermore, in the case where the core 16 is not provided,
There is a risk that the falling powder will support each other and cause a so-called hanging phenomenon, making it impossible to descend. Particularly in the lower part of the mold 15, the weight of all the powder filled above is applied, so that shelf hanging is likely to occur. However, in the above device, the powder's own weight is supported by the screw 19 forming the passage 20, so that a large amount of weight is not added to the lower part of the mold 15, and as a result, shelf suspension is less likely to occur. Moreover, even if shelf suspension occurs, the shelf suspension is quickly resolved by the pressure of the gas blown into the passage 20 by the gas blowing means, and the descent of the powder is not inhibited.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, mold 1
As the heating means for heating 5, it is also possible to use an induction heating type instead of using a resistance heating type heater.

Further, in the above embodiment, four passages 20 are provided by providing four screws 9 in the core, but the number of screws 19 and the passages 20 formed by them is determined by their pitch and cross-sectional area. It may be set as appropriate depending on the balance.

Further, in the above embodiment, the spiral groove-shaped passage 20 was formed by arranging the core 16 having the screw 19 in the cylindrical mold 15, but as shown in FIGS. 4 and 5, The passage 20 similar to that in the above embodiment can also be formed by integrally forming the screw 31 on the inner surface of the mold 30 and arranging the cylindrical core 32 at the center thereof. In this case, although the processing of the mold 30 becomes slightly complicated, the mold 3
Since the heat transfer effect from zero to the screw 31 is further enhanced, there is an advantage that the heating efficiency for the powder can be further improved.

"Effects of the Invention" As explained in detail above, the present invention heats the mold that passes through the furnace body vertically using a heating means, and the carbon powder that has flowed into the inside from the upper end of the mold is heated inside the mold. Since the carbon powder is heated and graphitized by a mold while passing through the mold, not only can continuous graphitization treatment of the carbon powder be realized, but also the passage through which the powder descends can be controlled by a screw installed in the mold. Because of the spiral groove shape, the powder is naturally stirred as it descends, and it is prevented from drifting or hanging on a shelf.Moreover, heat is transferred from the mold to the screw, so the powder is heated by the screw as well. This has the effect that carbon powder can be reliably and efficiently graphitized.

Further, if a gas blowing means for blowing gas into the passage is provided, even if shelf suspension occurs, the shelf suspension can be easily eliminated by gas pressure.

[Brief explanation of drawings]

1 to 3 show an embodiment of the graphite powder manufacturing apparatus according to the present invention, FIG. 1 is a complete sectional view showing the overall schematic structure, and FIG. 2 is a line taken along the line ■-■ in FIG. 3 is an enlarged view taken along the line m--m in FIG. 1. 4 and 5 show other embodiments, FIG. 4 is a complete sectional view of the main part thereof, and FIG. 5 is an enlarged view taken along the line V--V in FIG. 4. C... Carbon powder, B... Graphite powder, l
... Furnace body, 2 ... Preheating chamber, 3 ...
... Heating chamber, 4 ... Pre-cooling chamber, 5 ... Heater (heating means), 6 ... Charging chamber, 7 ...
...Charging hopper, 11...Cooling room, 12...
...Discharge hopper, 14...Screw feeder, 15...Mold, 16...Core, 18...Core material, 19...・Screw 20...Passway, 21...Gas blowing means, 21a, 21b...Gas blowing pipe, 21c...
... Gas supply source device, 22 ... Gas blow-off pipe, 30 ... Mold, 31 ... Screw 32 ... Core material.

Claims (2)

[Claims] (1) A graphite powder manufacturing device that graphitizes carbon powder by heating it to a high temperature, which includes a furnace body and a spiral groove formed by a screw provided inside the furnace body and vertically penetrating the furnace body. a mold having a shaped passage formed therein; and heating means provided inside the furnace body to heat the mold from the outside; 1. An apparatus for producing graphite powder, characterized in that the graphite powder is heated through the mold by the heating means while lowering the graphite powder, thereby graphitizing the graphite powder and taking it out from the lower end of the mold. (2) The graphite powder manufacturing apparatus according to claim 1, further comprising a gas blowing means for blowing gas into the passageway through a gas blowing pipe provided inside the mold. .