Carbonaceous granular heat treatment device and method

Abstract

The present invention provides a heat treatment device and method for carbonaceous particles, which can uniformly and continuously perform heat treatment of carbonaceous particles at high temperature for a long period of time without causing changes in the filling degree of carbonaceous particles or confusion in fluidity, or clogging in the furnace caused by these, thereby achieving improved productivity and workability. The heat treatment device includes: an input part, which is arranged above the furnace body and inputs carbonaceous particles into the furnace body. The input part includes: a distribution hopper, which distributes carbonaceous particles; a plurality of feeders, which are arranged below the distribution hopper and have the function of removing fine powder from the distributed carbonaceous particles; and a plurality of raw material bins, which are arranged below each feeder, so that the carbonaceous particles with fine powder removed descend inside and are input into the furnace body. The plurality of raw material bins are arranged at equal intervals in a concentric circle with the central axis of the furnace body.

Description

Technical Field

[0001] The invention relates to a heat treatment device and method for carbonaceous particles. Background Art

[0002] The physical properties of carbonaceous particles such as smokeless carbon particles, coke particles, carbonaceous granules, and mixed granules of metal oxides and carbon vary significantly due to the heat treatment temperature, and therefore require uniform heat treatment when used as raw materials for electrodes or raw materials for carbonaceous refractory materials, electronic materials, or battery materials. In addition, when a mixture of metal oxides and carbon is subjected to a reduction reaction by heat treatment to obtain carbides of various metals, uniform heat treatment is also indispensable in order to reliably perform the target reaction.

[0003] Therefore, the following method has been widely used as an electrical roasting technology, that is, carbonaceous particles such as smokeless carbon particles are placed in a vertical electrical heat treatment furnace, and electricity is directly applied to the carbonaceous particles, thereby continuously performing heat treatment at about 1500° C. to 2000° C. In addition, Patent Document 1 discloses a method of uniformly performing continuous graphitization at about 3000° C.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2002-167208 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the heat treatment of carbonaceous particles using a heat treatment device, it is necessary to transport the carbonaceous particles to the input position. Regarding the transportation method, there are methods of using vehicle transportation, subdividing into bags or cans such as flexible container bags and lifting by cranes, methods of using bucket elevators or conveying devices such as belt conveyors or screw conveyors, or air transportation, or methods of combining these conveying and transportation devices. In any of the conveying and transportation methods, forces caused by vibration, impact, and friction are applied to the carbonaceous particles. In particular, in the case of throwing carbonaceous particles from the top of the furnace, such as a vertical heat treatment furnace, the carbonaceous particles are affected by gravity, and thus the force acting on the carbonaceous particles is large. As a result, the carbonaceous particles are physically damaged, producing fine powder or fragments.

[0009] If the fine powder or fragments are mixed into the carbonaceous granules, not only the filling degree of the carbonaceous granules in the furnace changes, the heat treatment of the carbonaceous granules becomes uneven, but also the flow of the carbonaceous granules is blocked, and in the worst case, a stationary layer may be formed to cause clogging in the furnace. In addition, the flow of the carbonaceous granules is locally chaotic, and the flow rate per unit time of the carbonaceous granules falling in the furnace is different depending on the falling position, which may also cause the same problem.

[0010] In particular, in a vertical electrical heat treatment furnace that continuously heat treats carbonaceous particles by directly passing electricity through the carbonaceous particles, the change in resistivity associated with the change in filling degree affects the current path, resulting in a phenomenon in which current flows locally in the furnace body filled with carbonaceous particles, i.e., bias current.

[0011] When a bias flow occurs in a vertical electrical heat treatment furnace, not only can the carbonaceous particles not be uniformly heat treated, but sometimes the bias flow area becomes obviously hot. If such a significant high temperature area is locally generated, carbon sublimation will occur in the carbonaceous particles in the furnace. As a result, it is possible to cause local consumption of the electrode, or the sublimated gas may cool and condense, resulting in a so-called bridge portion, causing clogging in the furnace. If the carbonaceous particles are blocked in the furnace, it becomes difficult to continue continuous operation, and productivity decreases.

[0012] In order to solve the above-mentioned problems, the purpose of the present invention is to provide a heat treatment device and method for carbonaceous particles, which can continuously perform heat treatment of carbonaceous particles uniformly and for a long period of time without causing changes in the filling degree of carbonaceous particles or disturbances in fluidity, and clogging in the furnace caused by these, thereby achieving improved productivity.

[0013] Technical means of solving problems

[0014] The heat treatment apparatus for carbonaceous particles of the present invention has the following structure.

[0015] (1) is a heat treatment device for carbonaceous particles, which heat treats carbonaceous particles introduced into a furnace.

[0016] (2) The method comprises: a charging portion provided above the furnace body for charging the carbonaceous particles into the furnace body.

[0017] (3) The input part includes the following structure.

[0018] (3-1) comprising: a distribution hopper for distributing the carbonaceous particles.

[0019] (3-2) A plurality of feeders are provided below the distribution hopper and have a function of removing fine powders from the distributed carbonaceous particles.

[0020] (3-3) The method comprises: a plurality of raw material bins provided below each of the feeders, wherein the carbonaceous granules from which fine powder has been removed are caused to descend inside the bins, and the carbonaceous granules are fed into the furnace body.

[0021] (4) The plurality of raw material bins are arranged at equal intervals and are concentric with the central axis of the furnace body.

[0022] The heat treatment apparatus for carbonaceous particles of the present invention may further include the following structure.

[0023] (1) Each of the raw material bins includes: a cylindrical portion; and a tapered portion provided at a lower portion of the cylindrical portion and narrowed downward, wherein a tapered angle of the tapered portion is less than 30°.

[0024] (2) The distribution hopper is disposed at a position away from the central axis of the furnace body toward the outer circumference of the furnace body, and the plurality of feeders extend in a direction connecting the distribution hopper and the plurality of raw material bins.

[0025] (3) The method further includes: a cooling unit for cooling the heat-treated carbonaceous particles, wherein the cooling unit includes a discharge unit for adjusting the discharge amount of the cooled carbonaceous particles.

[0026] (4) It also includes: a cylindrical upper electrode and a cylindrical lower electrode, which are arranged vertically on the central axis of the furnace body; and a conductive tubular structure, which is electrically connected to the upper end of the lower electrode in a manner of surrounding the upper electrode, and heat treatment is performed by directly passing electricity to the carbonaceous particles inside the tubular structure through the upper electrode and the lower electrode.

[0027] (5) The feeder and the raw material bin face each other via an insulator.

[0028] The heat treatment method of carbonaceous particles of the present invention includes the following structure.

[0029] (1) A method for heat treating carbonaceous particles includes using a heat treating apparatus for carbonaceous particles, wherein the heat treating apparatus heat treats carbonaceous particles introduced into a furnace.

[0030] (2) Distributing the carbonaceous particles.

[0031] (3) Removing fine powders from the distributed carbonaceous particles.

[0032] (4) The carbonaceous granules from which fine powder has been removed are fed from a plurality of feeding positions which are arranged at equal intervals and are concentric with the central axis of the furnace body.

[0033] Effects of the Invention

[0034] The present invention can uniformly and continuously perform heat treatment of carbonaceous particles for a long period of time without causing changes in the filling degree of carbonaceous particles or disturbances in the flow, or clogging in the furnace caused by these, thereby achieving improved productivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a side view showing the heat treatment apparatus of carbonaceous particles according to the first embodiment.

[0036] Figure 2 It is a plan view showing the input portion of the first embodiment.

[0037] Figure 3 It is a side view showing the input part of the first embodiment.

[0038] Figure 4 It is a side view showing a charging hopper and a skirt according to the first embodiment.

[0039] Figure 5 It is a flowchart which shows the operation|movement of the heat treatment apparatus of the carbonaceous granular body which concerns on 1st Embodiment.

[0040] [Explanation of Symbols]

[0041] 1: Heat treatment device

[0042] 10: Investment Department

[0043] 11: Set up the platform

[0044] 12: Distribution hopper

[0045] 121: Cone

[0046] 13: Feeder

[0047] 13a: Insulator

[0048] 14: Raw material warehouse

[0049] 141: Cylinder

[0050] 142: Cone

[0051] 15: Loading hopper

[0052] 151, 152: Opening

[0053] 16: Skirt

[0054] 161, 162: Opening

[0055] 20: Heat treatment department

[0056] 21: Furnace body

[0057] 211: Furnace cover

[0058] 22: Upper electrode

[0059] 23: Combustion Chamber

[0060] 231: Chimney

[0061] 24: Tubular structure

[0062] 241, 242: Opening

[0063] 25: Lower electrode

[0064] 251, 252: Opening

[0065] 26: Insulation layer

[0066] 30: Cooling section

[0067] 31: Water cooling jacket

[0068] 311: Gas injection hole

[0069] 32: Discharge unit

[0070] 321: Pressure measurement sensor

[0071] 33: Valve. DETAILED DESCRIPTION

[0072] [1. First embodiment]

[0073] [1-1. Structure]

[0074] [Carbonaceous particles]

[0075] First, the carbonaceous granules A used in the heat treatment device of the carbonaceous granules of the first embodiment are described. The carbonaceous granules A can use particles such as smokeless carbon particles, coke particles, granules containing a mixture of these, and granules containing a mixture of metal oxides and carbon. In addition, as smokeless carbon or coke, uncalcined products may also be included, and coke includes petroleum coke, coal coke, fluidized coke, needle coke, etc. Smokeless carbon particles and coke particles are particles of about 10 mm to 20 mm, for example, obtained by crushing blocky smokeless carbon or coke. Granulated bodies are, for example, particles obtained by mixing a binder or water with raw materials such as carbon powder, artificial graphite powder, and metal oxides derived from smokeless carbon or coke, and formed using a granulator such as a disc pelletizer, and then hardened by drying. The binder can be, for example, starch powder, and in particular, α-corn starch powder. As long as the hardening and carbonization treatment can be performed, the binder may also be pitch or phenol resin, other synthetic polymer compounds, water-soluble polysaccharides, etc. The carbonaceous granules A of this embodiment are cylindrical granules with a smooth surface, a diameter of about 10 mm, and a height of 10 mm to 15 mm. In this embodiment, the carbonaceous granules A are directly energized to generate Joule heat and are heat treated.

[0076] [Heat treatment equipment]

[0077] Next, the heat treatment apparatus for carbonaceous particles according to the first embodiment will be described in detail with reference to the drawings. Figure 1 : is a side view showing the structure of the heat treatment device 1 of the present embodiment. The heat treatment device 1 includes a furnace body 21 for heat treatment of carbonaceous granules A. For the furnace body 21 of the present embodiment, a direct current heating method for heat treatment by directly energizing, or an indirect heating method for heat treatment by including a heat source in the outer periphery and heating the furnace core tube or the heating container from the outside, etc. can be used. Hereinafter, the furnace body 21 is described as a vertical electric heat treatment furnace of the direct current heating method. The heat treatment device 1 is energized during the period when the carbonaceous granules A introduced from the top of the furnace body 21 slowly descend inside the furnace body 21, thereby continuously heat treating the carbonaceous granules A. The heat treatment device 1 includes: an introduction part 10 for introducing the carbonaceous granules A into the furnace body 21; a heat treatment part 20 for heat treating the introduced carbonaceous granules A; and a cooling part 30 for cooling the heat-treated carbonaceous granules A. The introduction part 10, the heat treatment part 20 and the cooling part 30 are arranged in sequence from the top to the bottom of the furnace body 21. The furnace body 21 constitutes a part of the heat treatment unit 20. The carbonaceous particles A are assumed to fill the furnace body 21 and at least a part of the input unit 10 and the cooling unit 30. In this specification, upward refers to the direction opposite to gravity, and downward refers to the direction along gravity.

[0078] [Investment Department]

[0079] One side reference Figures 2 to 4 , while explaining the input part 10. The input part 10 inputs the carbonaceous granules A from above into the furnace body 21, and includes a stand 11, a distribution hopper 12, a feeder 13, a raw material bin 14, a charging hopper 15 and a skirt 16 along the input path of the carbonaceous granules A.

[0080] The stand 11 is a stand provided at the upper part of the input part 10, and is used to place a flexible container bag lifted by a crane or the like. The flexible container bag is filled with carbonaceous granules A to be heat-treated, and the carbonaceous granules A are input from the flexible container bag to the distribution hopper 12. The distribution hopper 12 is a container for distributing the input carbonaceous granules A from a hole provided on the bottom surface. The distribution hopper 12 of the present embodiment is provided with a hole at each of the four corners of the bottom surface of a roughly rectangular shape, for example. Conical portions 121 extending downward in a funnel shape from the edge of the hole are provided in each of these four holes. The lower end of each of the cones 121 is open. The carbonaceous granules A input into the distribution hopper 12 descend from these four holes inside the cone 121, and are discharged to the feeder 13 directly below the openings provided at the lower ends of the cones 121.

[0081] The feeder 13 is a mechanism and path for delivering carbonaceous granules A from the distribution hopper 12 to the raw material bin 14. The feeder 13 has the function of removing fine powder contained in the carbonaceous granules A. In the present embodiment, a screen with a mesh size of 4 mm or more is provided on the path of the feeder 13, for example. The screen is, for example, a metal wire mesh or punching metal. That is, the feeder 13 can remove the fine powder contained in the carbonaceous granules A during the process of delivering the carbonaceous granules A. Furthermore, the feeder 13 can also be, for example, a vibrating feeder having a vibration function based on an electromagnetic vibration method or the like. In the case where the feeder 13 is a vibrating feeder, the carbonaceous granules A can be delivered while being vibrated on the feeder 13, so that the fine powder can be more effectively removed from the screen provided on the path. Moreover, the feeder 13 and the raw material bin 14 face each other, for example, separated by an insulator 13a including a rubber tube or a rubber plate, a magnetic plate, or the like. When the heat treatment apparatus 1 is in operation, it is preferable to adopt a structure in which the feeder 13 and the raw material bin 14 are connected via the insulator 13 a to prevent the intrusion of dust and the like from the outside.

[0082] The raw material bin 14 is a container for containing carbonaceous particles A. The material of the raw material bin 14 is preferably a material with excellent durability and corrosion resistance. In particular, when the material of the raw material bin 14 is steel, it is possible that rust on the steel is mixed into the furnace. Therefore, the material of the raw material bin 14 is, for example, heat-resistant stainless steel, and SUS310S is particularly suitable. The raw material bin 14 includes a cylindrical cylindrical portion 141 that receives the carbonaceous particles A from the feeder 13, and a conical portion 142 that is provided at the lower portion thereof and narrows downward. The cylindrical portion 141 and the conical portion 142 are connected internally, and the lower portion of the conical portion 142 is open, so that the carbonaceous particles A sent from the feeder 13 can descend inside the raw material bin 14. Inside the raw material bin 14, a fullness meter or flow meter (not shown) or a sensor having the same function is provided, and the amount or flow rate of the carbonaceous granules A inside the raw material bin 14 and the amount sent from the feeder 13 in conjunction with the operation and stop of the feeder 13 are adjusted, thereby maintaining the carbonaceous granules A inside the raw material bin 14 at an arbitrary amount or flow rate. At the lower part of the conical portion 142, an opening and closing damper (not shown) is provided for opening and closing the opening, and the descent of the carbonaceous granules A can be temporarily stopped here when the type of the carbonaceous granules A is switched or when a fault occurs. The cone angle of the cone 142 is, for example, 30° or less, and particularly preferably 15° or less.

[0083] The raw material bin 14 of this embodiment is provided with four holes corresponding to the number of distribution holes for distributing the carbonaceous granules A in the distribution hopper 12. The four raw material bins 14 are arranged at equal intervals on the approximate concentric circles of the central axis of the furnace body 21 provided thereunder. That is, the four raw material bins 14 are arranged at 90° circumferential angles on the circumference of the circle centered on the central axis. In addition, the so-called approximate concentric circles means that if the dimensional error of each structure and the degree of assembly error are considered, they are set on concentric circles.

[0084] like Figure 2 and Figure 3 As shown, the distribution hopper 12 of this embodiment is not arranged directly above the four raw material bins 14. In other words, the distribution hopper 12 is arranged at a position away from the central axis of the furnace body 21 arranged below it toward the outer peripheral direction of the furnace body 21. Along with this, a plurality of feeders 13 are arranged extending in the direction connecting the distribution hopper 12 and the raw material bin 14, and in this embodiment, they are arranged extending in a substantially horizontal direction. That is, the farther the distribution hopper 12 is from directly above the four raw material bins 14, the longer the path length of the feeder 13 becomes. In addition, as Figure 2 As shown, the path lengths of the feeders 13 are different from each other, but even the shortest path length can sufficiently remove fine powder. The length of the shortest feeder 13 is, for example, 70 cm.

[0085] like Figure 4As shown, the charging hopper 15 provided below the raw material bin 14 is a truncated cone-shaped container with openings 151 and 152 at its upper and lower ends, respectively, and its inner diameter is narrowed downward. The skirt 16 provided below the charging hopper 15 is a truncated cone-shaped or cylindrical container with openings 161 and 162 at its upper and lower ends, respectively, and its inner diameter is narrowed downward. The opening 152 of the charging hopper 15 and the opening 161 of the skirt 16 are provided continuously. Moreover, the charging hopper 15 and the skirt 16 are both provided coaxially with the central axis of the furnace body 21.

[0086] The charging hopper 15 and the skirt 16 are preferably containers with a double-layer structure having heat insulation properties. By setting the double-layer structure to have heat insulation properties, the radiation heat or heat transfer from the heat treatment section 20 can be mitigated. The material of the charging hopper 15 and the skirt 16 is preferably a material with excellent durability and corrosion resistance. In particular, when the material of the charging hopper 15 and the skirt 16 is steel, rust of the steel may be mixed into the furnace. Therefore, the material of the charging hopper 15 and the skirt 16 is, for example, heat-resistant stainless steel, and SUS310S is particularly suitable. Moreover, the internal space of the double-layer structure may be directly set as an air layer in the form of a cavity, but air or cooling gas may be blown in, and then a heat insulating material may be buried.

[0087] The charging hopper 15 and the skirt 16 temporarily store the carbonaceous particles A discharged from the raw material bin 14 and feed them into the heat treatment section 20. Figure 1 As shown in FIG. 1 , an upper electrode 22 to be described later penetrates the inside of the hopper 15 and the skirt 16 .

[0088] [Heat Treatment Department]

[0089] The heat treatment unit 20 includes: a furnace body 21; an upper electrode 22; a combustion chamber 23 for temporarily storing the carbonaceous granules A introduced from the skirt 16; a tubular structure 24 provided at the lower part of the combustion chamber 23, in which the carbonaceous granules A are lowered; a lower electrode 25 provided at the lower part of the tubular structure 24, in which the carbonaceous granules A are lowered; and a heat insulating layer 26 provided between the inner circumference of the furnace body 21 and the outer circumferences of the tubular structure 24 and the lower electrode 25. That is, the carbonaceous granules A in the heat treatment unit 20 are lowered in the combustion chamber 23, the tubular structure 24, and the lower electrode 25 in sequence.

[0090] The furnace body 21 is a cylindrical furnace shell lined with a refractory material (not shown). The refractory material is, for example, a refractory brick. A cylindrical upper electrode 22 is provided on the central axis of the furnace body 21 to directly energize the carbonaceous granules A. The upper electrode 22 penetrates the charging hopper 15 and the skirt 16 provided above the furnace body 21, and further penetrates the combustion chamber 23, and extends to the inside of the tubular structure 24.

[0091] A combustion chamber 23 is provided inside the furnace body 21 in a manner surrounding the upper electrode 22. The combustion chamber 23 is a cylindrical space for temporarily storing the carbonaceous particles A introduced from the skirt 16 of the introduction portion 10. The internal space of the combustion chamber 23 has a side surface formed by the inner peripheral surface of the furnace body 21, an upper surface formed by a furnace cover 211 formed by connecting the outer periphery of the skirt 16 with the upper inner peripheral portion of the furnace body 21, and a bottom surface formed by the upper surface of the heat insulating layer 26 present on the outer peripheral surface of the tubular structure 24. The furnace cover 211 includes, for example, a heat-resistant plate, and may also include a steel material lined with a cast material (caster) or a refractory material. For example, a heat-resistant plate may also use a formed body including heat-resistant fibers. Moreover, as Figure 4 As shown, the skirt 16 penetrates the upper surface of the combustion chamber 23 and protrudes into the combustion chamber 23, and the opening 162 provided at the lower end of the skirt 16 is separated from the bottom surface of the combustion chamber 23 by a predetermined distance in the vertical direction. The predetermined distance is, for example, 30 cm to 100 cm, preferably 50 cm to 80 cm. By adjusting the predetermined distance and the diameter of the opening 162 of the skirt 16, the carbonaceous particles A are accumulated in a manner that they exist continuously in a hammer shape from the opening 162 to the bottom of the combustion chamber 23.

[0092] The chimney 231 is provided in the combustion chamber 23. It is particularly preferred that a plurality of chimneys 231 are provided at equal intervals in the circumferential direction of the cylindrical combustion chamber 23. The so-called plurality of chimneys 231 are provided at equal intervals in the circumferential direction, for example, if two chimneys 231 are provided, they are provided at intervals of 180°, if three chimneys 231 are provided, they are provided at intervals of 120°, and if four chimneys 231 are provided, they are provided at intervals of 90° with the central axis of the combustion chamber 23 as the center. In the present embodiment, two chimneys 231 are provided at intervals of 180°.

[0093] A conductive tubular structure 24 is provided at the lower part of the combustion chamber 23 so as to surround at least a part of the upper electrode 22. The tubular structure 24 includes, for example, artificial graphite. The tubular structure 24 includes openings 241 and 242 at its upper and lower ends, respectively, and is connected to the combustion chamber 23 through the opening 241, and is connected to the inside of the lower electrode 25 provided at the lower part of the tubular structure 24 through the opening 242. The lower electrode 25 is a cylindrical electrode provided at the lower part of the tubular structure 24, facing the upper electrode 22 and away from it downward by a predetermined distance. The lower electrode 25 includes openings 251 and 252 at its upper and lower ends, respectively. The opening 251 of the lower electrode 25 is electrically connected to the opening 242 of the tubular structure 24 through a support ring not shown. Therefore, when the upper electrode 22 and the lower electrode 25 are energized, a heating zone is formed from the opening 241 of the tubular structure 24 to the opening 251 of the lower electrode 25. In other words, the carbonaceous particles A are heat-treated inside the tubular structure 24 by energizing the upper electrode 22 and the lower electrode 25. In addition, the upper electrode 22, the combustion chamber 23, the tubular structure 24, the openings 241 and 242, the lower electrode 25, and the openings 251 and 252 of the heat treatment unit 20 are preferably all arranged coaxially with the central axis of the furnace body 21.

[0094] A heat insulating layer 26 containing, for example, carbon black is provided between the outer peripheral surfaces of the tubular structure 24 and the lower electrode 25 and the inner peripheral surface of the furnace body 21. The heat insulating layer 26 blocks heat generated around the tubular structure 24 and the lower electrode 25 from the outside.

[0095] [Cooling Department]

[0096] The cooling section 30 is provided with a cylindrical water-cooling jacket 31, a discharge section 32 and a valve 33. The water-cooling jacket 31 and the discharge section 32 are provided with pipes (not shown) for flowing cooling water. The carbonaceous granules A discharged from the heat treatment section 20 are cooled by passing through the inside of the water-cooling jacket 31. In addition, near the upper end of the water-cooling jacket 31, a gas blowing hole 311 is provided for blowing an inert gas such as argon or nitrogen into the lower electrode 25 and the tubular structure 24. It is preferred that a plurality of gas blowing holes 311 are provided at equal intervals in the circumferential direction of the water-cooling jacket 31. The so-called plurality of gas blowing holes 311 are provided at equal intervals in the circumferential direction, for example, if two are provided, then the plurality of gas blowing holes 311 are provided at intervals of 180°, if three are provided, then the plurality of gas blowing holes 311 are provided at intervals of 120°, and if four are provided, then the plurality of gas blowing holes 311 are provided at intervals of 90° with the central axis of the water-cooling jacket 31 as the center. The gas blowing holes 311 of the present embodiment are provided, for example, at intervals of 90°.

[0097] The discharge unit 32 sends the carbonaceous granules A cooled inside the water-cooling jacket 31 to the valve 33 with excellent airtightness. The discharge unit 32 is, for example, a rotary wing type quantitative discharge device that adjusts the flow rate and discharge amount of the carbonaceous granules A per unit time in the heat treatment unit 20 and the water-cooling jacket 31. In addition, the rotary wing type quantitative discharge device can receive the weight information of the carbonaceous granules A discharged from the valve 33 described later from a weight meter (load cell) not shown in the figure provided at the discharge destination of the valve 33, and adjust the rotation speed of the rotary wing according to the change of the weight information, thereby adjusting the discharge amount of the carbonaceous granules A. The adjustment can be performed by setting an arbitrary weight measurement time, for example, every 1 minute. In addition, the discharge unit 32 is a closed structure that is not opened except for the discharge port for discharging the carbonaceous granules A to the valve 33, and is provided with a pressure measurement sensor 321. The pressure measurement sensor 321 can be used to measure the internal pressure inside the heat treatment unit 20 and the water-cooling jacket 31. If the pressure difference between the inside and outside of the furnace body 21 is -25 Pa to 200 Pa, the possibility of air being sucked into the furnace from the outside of the furnace body 21 is reduced.

[0098] The valve 33 discharges the carbonaceous particles A discharged from the discharge section 32 from the heat treatment device 1. In other words, the cooling section 30 includes a dual discharge structure including the discharge section 32 and the valve 33. The path space of the carbonaceous particles A from the discharge section 32 to the valve 33 is sealed.

[0099] The valve 33 may include a sealed space inside, and play a role as a so-called air lock. The so-called sealing mentioned here refers to the airtightness to the extent that the valve 33 can be pressure-separated from the outside, and also includes the case where it is not completely sealed. The valve 33 is, for example, a rotary valve. In this way, by configuring the valve 33 with excellent airtightness after the discharge part 32, the airtightness inside the heat treatment part 20 and the cooling part 30 is improved.

[0100] [1-2. Function]

[0101] One side reference Figure 5, the operation of the heat treatment device 1 of the present embodiment is explained while referring to the flowchart. First, the flexible container bag filled with carbonaceous granules A is lifted by a crane or the like and placed on a stand 11 provided on the upper part of the input part 10 (step S01). The carbonaceous granules A loaded into the flexible container bag are put into the distribution hopper 12. The put-in carbonaceous granules A descend downward from the four holes and four cones 121 provided at the four corners of the distribution hopper 12, and are discharged to the feeder 13 provided directly below the outlets of these four cones 121. The carbonaceous granules A on each feeder 13 are sent to the corresponding raw material bin 14. At this time, in the process of the feeder 13 sending out the carbonaceous granules A, the fine powder contained in the carbonaceous granules A is classified by a sieve provided on the path of the feeder 13, and is removed from a path not shown in the figure. The fine powder is generated in the process of conveying the carbonaceous granules A, but it is ideal to remove it as much as possible from the carbonaceous granules A to be heat treated. The reason is that if the fine powder enters the heat treatment section 20 while entering the gaps between the carbonaceous particles A, the filling degree or fluidity inside the furnace body 21 will locally change, making the resistivity uneven, which may cause furnace blockage or bias flow when power is turned on as described in the subject of this specification.

[0102] The carbonaceous granules A from which the fine powder has been removed descend in the raw material bin 14. In this way, the carbonaceous granules A are distributed to four parts among the distribution hopper 12, the feeder 13, and the raw material bin 14 and descend (step S02).

[0103] The carbonaceous granules A discharged from the four raw material bins 14 descend inside the charging hopper 15 and the skirt 16, and are thereby thrown into the combustion chamber 23 of the heat treatment section 20 from the opening 162 of the skirt 16. More specifically, the upper electrode 22 described later penetrates inside the charging hopper 15 and the skirt 16, so that the carbonaceous granules A pass through the inner circumference of the charging hopper 15 and the skirt 16 and the outer circumference of the upper electrode 22 and descend, and are thrown into the combustion chamber 23 (step S03).

[0104] The opening 162 of the skirt 16 is separated from the bottom surface of the combustion chamber 23 by a predetermined distance in the vertical direction, so that the carbonaceous granules A introduced from the opening 162 of the skirt 16 are placed around the upper electrode 22, and are accumulated in a hammer shape, for example, at an angle of repose, inside the combustion chamber 23, and a part of them descends into the tubular structure 24. More specifically, the upper electrode 22 penetrates the inside of the tubular structure 24, so that the carbonaceous granules A pass through the outer peripheral surface of the upper electrode 22 and the inner peripheral surface of the tubular structure 24 and descend (step S04).

[0105] In addition, since the temperature inside the combustion chamber 23 and the upper part inside the furnace body 21 is relatively high, combustible gas is generated by the binder contained in the carbonaceous granules A. In addition, sometimes the carbon powder as the raw material of the carbonaceous granules A contains volatile substances, and this volatile substance volatilizes and becomes combustible gas. These combustible gases burn inside the high-temperature combustion chamber 23. The combustion gas is exhausted from the chimney 231 provided in the combustion chamber 23, thereby generating a draft effect inside the combustion chamber 23 and the furnace body 21 and generating an upward airflow. Due to the upward airflow, the combustible gas is guided to the conical surface of the carbonaceous granules A and burns on the conical surface. In addition, an inert gas such as argon or nitrogen is injected into the carbonaceous granules A inside the furnace body 21 from the gas injection hole 311 below. Therefore, the combustion of the combustible gas stops at the conical surface formed by the carbonaceous granules A inside the combustion chamber 23, and does not proceed to the inside of the carbonaceous granules A. In other words, the carbonaceous particles A are oxidized only on the cone surface, and the inside of the cone is not oxidized. Thus, the carbonaceous particles A are oxidized only on the cone surface, thereby preventing the oxidation of the carbonaceous particles A that pass through the inside of the cone and fall from the skirt 16 to the inside of the tubular structure 24.

[0106] In this embodiment, two chimneys 231 are provided every 180 degrees. If they are arranged at equal intervals, there is no deviation in the generation of airflow inside the combustion chamber 23, and there is no deviation in the path of the combustible gas generated by the carbonaceous granules A rising inside the carbonaceous granules A, so that the temperature of the carbonaceous granules A inside the furnace body 21 becomes uniform.

[0107] By energizing the upper electrode 22 and the lower electrode 25, the carbonaceous particles A descending in the tubular structure 24 are directly energized, and the carbonaceous particles A are heat-treated using the Joule heat generated by the carbonaceous particles A (step S05). The carbonaceous particles A are graphitized by the heat treatment. The heat-treated carbonaceous particles A descend in the lower electrode 25, are discharged from the opening 252 to the cooling part 30, are cooled by the water-cooling jacket 31 of the cooling part 30, and are discharged from the heat treatment device 1 by the discharge part 32 and the valve 33 (step S06).

[0108] [1-3. Effect]

[0109] (1) The heat treatment apparatus 1 of the present embodiment includes a feeder 13, which has a function of removing fine powder contained in the carbonaceous granules A, and thus can remove fine powder from the carbonaceous granules A that are transported and transported to be the object of heat treatment. In addition, the heat treatment apparatus 1 of the present embodiment also includes a distribution hopper 12 and a plurality of raw material bins 14 arranged at equal intervals in the circumferential direction, so that the flow rate per unit time of the carbonaceous granules A descending between the inner peripheral surface of the charging hopper 15 and the skirt 16 and the outer peripheral surface of the upper electrode 22 can be prevented from being segregated depending on the descending position. As a result, the filling degree of the carbonaceous granules or the flow rate per unit time can be made uniform in the furnace, thereby reducing the possibility of uneven heat transfer or the formation of a stationary layer of carbonaceous granules and causing clogging in the furnace.

[0110] (2) The taper angle of the raw material bin 14 of the heat treatment device 1 of the present embodiment is 30° or less. By setting the taper angle to 30° or less, the lateral pressure (pressure in the horizontal direction) of the material (carbonaceous granules A) near the wall can be reduced, and the flow of the material near the wall can be ensured, thereby setting a mass flow. As a result, the particle size separation of the carbonaceous granules A is not caused in the raw material bin 14, and the material discharged from the opening opened at the lower part of the taper 142 of the raw material bin 14 is uniform without deviation (unevenness). Moreover, the carbonaceous granules A supplied from the distribution hopper 12 at the same time are uniformly put into the furnace without time difference, ensuring the same quality of the materials put into the furnace, so that the carbonaceous granules A put in can be divided or batch identified, and the convenience of management and operation headed by traceability is also improved.

[0111] (3) The distribution hopper 12 of the present embodiment is disposed at a position away from the central axis of the furnace body 21 toward the outer peripheral direction of the furnace body 21, and accordingly, the plurality of feeders 13 extend in a direction connecting the distribution hopper 12 and the plurality of raw material bins 14. Thus, a long path of the feeder 13 can be ensured, and thus fine powder removal can be fully performed by vibration.

[0112] (4) The heat treatment apparatus 1 of the present embodiment includes the discharge section 32, so that the discharge amount per unit time of the carbonaceous granules A can be adjusted. As a result, the carbonaceous granules A can gradually descend inside the heat treatment section 20 and the water cooling jacket 31 without falling freely, thereby alleviating the load on the carbonaceous granules A and preventing the generation of fine powder.

[0113] (5) The heat treatment apparatus 1 of the present embodiment performs heat treatment by directly energizing the carbonaceous granules A inside the tubular structure 24 using the upper electrode 22 and the lower electrode 25. In the case of such a vertical electric heat treatment furnace of direct energization heating method, the less the density segregation of the carbonaceous granules A is, the less the bias current is during energization, so that the heat treatment temperature of the carbonaceous granules A inside the tubular structure 24 can be made uniform. Furthermore, the possibility of carbon sublimation caused by the local high temperature portion due to the bias current can be reduced, so even if the heat treatment apparatus 1 is continuously operated for a long period of time, the possibility of clogging inside can be reduced.

[0114] (6) In the conventional heat treatment apparatus, the carbonaceous particles are continuously present from the input part to the heat treatment part, so there is a problem that if the carbonaceous particles are energized in the heat treatment part, current also flows in the raw material bin. However, in the heat treatment apparatus 1 of the present embodiment, the feeder 13 is insulated from the raw material bin 14 and also insulated from the house, so the feeder 13 and the structure arranged above it are electrically insulated. Thus, the possibility of leakage can be eliminated, thereby reducing the risk of failure of the auxiliary equipment accompanied by leakage, or the risk of electric shock to the operator who puts in the carbonaceous particles A. Moreover, there is no leakage, thereby also suppressing wasteful power consumption.

[0115] [2. Other embodiments]

[0116] In this specification, multiple embodiments of the present invention are described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments or their modifications are included in the scope or gist of the invention, and similarly, are included in the invention described in the claims and their equivalents.

[0117] (1) In the above embodiment, the stand 11 for placing the flexible bulk bag is used, but if the carbonaceous granules A are put into the distribution hopper 12 by a method other than the flexible bulk bag, the stand 11 may not be provided. For example, when the carbonaceous granules A are transported to the distribution hopper 12 by a transport device such as a bucket elevator, a belt conveyor, a screw conveyor, or a combination thereof, or by air transport, the stand 11 may not be provided.

[0118] (2) In the above embodiment, the distribution hopper 12 is disposed at a position away from the central axis of the furnace body 21 disposed below the distribution hopper 12 toward the outer circumference of the furnace body 21, but it may be disposed on the central axis of the furnace body 21, that is, on the central axis of the concentric circle in which the four raw material bins 14 are disposed. In this case, the path lengths of the feeders 13 can all be made equal, and thus the removal of fine powder can also be made uniform.

[0119] (3) In the above embodiment, the vibration function of the feeder 13 is set to an electromagnetic vibration mode, but it can also be a vibration motor (eccentric motor) mode. Moreover, even if the feeder 13 for delivering the carbonaceous granules A is not provided, the distribution hopper 12 can be directly connected to the raw material bin 14, and a sieve leading to a path not shown in the figure can be provided at the connection part, thereby removing fine powder from the carbonaceous granules A to be heat-treated.

[0120] (4) In the above embodiment, four raw material bins 14 are arranged at equal intervals on the approximate concentric circle of the central axis of the furnace body 21. However, when the number of raw material bins 14 is set to two, three, or five or more, it is also preferred to arrange them at equal intervals on the approximate concentric circle of the central axis of the furnace body 21. For example, if two are provided, they are arranged every 180°, if three are provided, they are arranged every 120°, and if five are provided, they are arranged every 72°. Of course, the number of distributions of the distribution hopper 12 or the number of roots of the feeder 13 is made consistent with the number of bins 14.

[0121] (5) In the above embodiment, the furnace body 21 is a vertical electric heat treatment furnace with direct electric heating, but it can also be a vertical heat treatment furnace with indirect heating that includes a heat source at the outer periphery and heats the furnace core tube or heating container from the outside to perform heat treatment.

[0122] (6) In the above embodiment, the gas injection hole 311 is provided at the upper part of the water cooling jacket 31, but a gas injection hole may be further provided to penetrate in the upper electrode 22 in the vertical direction. By blowing an inert gas such as argon or nitrogen into the tubular structure 24 and the lower electrode 25 from the gas injection hole in the same manner as the gas injection hole 311, the inside of the carbonaceous granules A is filled with the inert gas, and the carbonaceous granules A are prevented from reacting with the air flowing in from the outside of the furnace body 21 and being oxidized from the inside.

[0123] (7) In the above embodiment, the discharge section 32 is set as a rotary wing type quantitative discharge device, but any device can be used as long as the discharge volume can be adjusted and the set amount can be quantitatively discharged. For example, a rotating disk method or any material cutting device can also be used. In addition, in the above embodiment, a load cell is set at the discharge destination of the valve 33 and the discharge section 32 is adjusted based on the information thereof, but the discharge section 32 may also have a built-in load cell or a weight measurement function.

[0124] (8) In the above embodiment, the valve 33 is a rotary valve, but any valve may be used as long as it can function as an air lock by combining with the discharge portion 32. In addition to the rotary valve, a double damper or a triple damper is suitable. In addition, the discharge portion 32 and the valve 33 may be provided with a certain degree of airtightness, and may not be completely airtight.

Claims

1. A heat treatment device for carbonaceous particles, include: The heat treatment part comprises: a furnace body; an upper electrode; a combustion chamber; and a lower electrode, wherein the carbonaceous particles in the heat treatment part descend in the combustion chamber and the lower electrode in sequence. The input part is arranged above the furnace body and inputs the carbonaceous particles into the furnace body. The input unit includes: A distribution hopper for distributing the carbonaceous particles; A plurality of feeders are provided below the distribution hopper and have the function of removing fine powders from the distributed carbonaceous granules; and A plurality of raw material bins are provided below each of the feeders, so that the carbonaceous granules from which the fine powder has been removed are lowered inside and the carbonaceous granules are fed into the furnace body. The plurality of raw material bins are arranged at equal intervals in a concentric circle with the central axis of the furnace body; A loading hopper disposed below the raw material bin has openings at its upper and lower ends respectively; A skirt seat provided at the lower part of the charging hopper, with openings provided at the upper and lower ends thereof; The charging hopper and the skirt temporarily store the carbonaceous granules discharged from the raw material bin and introduce the carbonaceous granules into the heat treatment section; The combustion chamber temporarily stores the carbonaceous particles introduced from the skirt; The upper electrode penetrates inside the charging hopper and the skirt.

2. The heat treatment device for carbonaceous particles according to claim 1, in, Each of the raw material bins comprises: a cylindrical portion having a cylindrical shape; and The conical portion is provided at the lower part of the cylindrical portion and narrows downward. The taper angle of the taper portion is 30° or less.

3. The heat treatment device for carbonaceous particles according to claim 1 or 2, in, The distribution hopper is arranged at a position away from the central axis of the furnace body in the peripheral direction of the furnace body. The plurality of feeders extend in a direction connecting the distribution hopper with the plurality of raw material bins.

4. The heat treatment device for carbonaceous particles according to claim 1 or 2, further comprising: include: a cooling section for cooling the heat-treated carbonaceous particles; The cooling unit includes a discharge unit that adjusts a discharge amount of the cooled carbonaceous particles.

5. The heat treatment device for carbonaceous particles according to claim 1 or 2, further comprising: include: A cylindrical upper electrode and a cylindrical lower electrode are arranged vertically on the central axis of the furnace body; as well as A conductive tubular structure is electrically connected to the upper end of the lower electrode in a manner surrounding the upper electrode, The carbonaceous particles in the tubular structure are directly energized by the upper electrode and the lower electrode to perform heat treatment.

6. The heat treatment device for carbonaceous particles according to claim 5, in, The feeder and the raw material bin face each other via an insulator.

7. A method for heat treating carbonaceous particles, comprising using the heat treating device for carbonaceous particles according to any one of claims 1 to 6, wherein the heat treating device for carbonaceous particles heat treats the carbonaceous particles introduced into a furnace body, and distributing the carbonaceous particles, Removing fine powders from the distributed carbonaceous particles, respectively, The carbonaceous granules from which fine powder has been distributed and removed are fed from a plurality of feeding positions provided at equal intervals and concentrically with the central axis of the furnace body.

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