Method for manufacturing an electrical conductor and heating element, and heating device using the heating element

Abstract

Heating device (50) in which a heating element (51) comprising a carbonized material (19) formed by carbonizing a silicon-containing vegetable raw material, continuous carbon fibers (63) formed by mixing and spinning the carbonized material with a resin, a carbon fiber bundle (62) formed by combining the carbon fibers into a bundle, and a heating element that receives the carbon fiber bundle (62) in a flexible tube (61) is used, characterized in that a circumference of the heating element is sheathed with a net-shaped electrical conductor (53), the electrical conductor and the carbon fiber bundle are electrically connected to one end of the heating element via a connecting part (57), one circumference of the electrical conductor is additionally encased with a flexible, thermally conductive and insulating outer sheath (56), and a feed-in terminal (52) is provided which supplies current to another end of the heating element.

Description

Technical field

[0001] The present invention relates to an electric conductor and a heating element formed from a fiber bundle obtained with a plant raw material and the like as a carbon source, by carbonizing this carbon source into a carbonized material and forming a bundle of fibers containing the carbonized material, as well as a method for producing the electric conductor and the heating element, and a heating device in which the heating element is used. State of the art

[0002] Conventional methods for producing nanocarbon include arc discharge, laser evaporation, chemical vapor deposition (CVD), and the like. Among these, the "supergrowth" method, a form of chemical vapor deposition (CVD), is known to be suitable for mass production and is used to produce single-layer carbon nanotubes in large quantities.

[0003] For example, Patent Document 1 describes the invention of a nanocarbon production apparatus characterized by producing nanocarbon from an organic material to be treated, comprising a thermal decomposition liquid collecting means for collecting a tar-containing thermal decomposition liquid after thermal decomposition of an organic material to be treated, a tar-containing thermal decomposition liquid removing means for removing the tar-containing thermal decomposition liquid from the collected tar-containing thermal decomposition liquid, and a nanocarbon production means for producing nanocarbon from the thermal decomposition liquid after removing the tar-containing thermal decomposition liquid.

[0004] As another example, Patent Document 2 describes the invention of a nanocarbon production apparatus characterized by comprising a rotary drum including a reducing atmosphere thermal decomposition chamber and a nanocarbon production chamber separated by a partition plate having a through-hole in the center thereof, a nanocarbon production plate disposed in the nanocarbon production chamber, an electric heater disposed in the outer peripheral region of the rotary drum, a raw material supply means for supplying a biomass raw material or a waste substance to the thermal decomposition chamber, and a scraping means for scraping off the nanocarbon produced on the nanocarbon production plate.wherein the biomass raw material or waste substance is thermally decomposed in the thermal decomposition chamber, a hydrocarbon-containing thermal decomposition gas is introduced into the nanocarbon production chamber, and the thermal decomposition gas in the nanocarbon production chamber is brought into contact with the nanocarbon production plate under a reducing atmosphere, whereby nanocarbon is formed and grown on the nanocarbon production plate.

[0005] Patent Document 3, for example, describes the invention of a method for producing a sintered body containing carbon nanohorns, characterized in that the method includes a sintering step in which a preform body containing carbon nanohorns produced by arc discharge in a liquid is sintered by heating under pressure at a temperature of 1000°C or higher.

[0006] Furthermore, the carbon nanotubes produced by these manufacturing methods exhibit excellent electrical conductivity, thermal conductivity, and the like, thus finding applications as heating elements. For example, a structure in Patent Document 4 is characterized by including heating fibers in which at least one or more carbon fibers are interwoven with glass fibers at a specific ratio, connecting terminals provided at both ends of the heating fibers and applying current from a power supply line, and a covering agent covering the surface of the heating fibers and the connecting terminals. This proposes an easily deformable heating element because heating elements using carbon fibers, in addition to being able to withstand high temperatures, also possess high tensile strength, thus preventing them from cracking or being damaged even when subjected to tensile force.

[0007] Document CN108217625A provides a method for producing nanocarbon microparticles. The production method is characterized by comprising the following steps: Step I: digesting mallow plants and generating a lignin-containing solution; Step II: extracting lignin condensate from the lignin-containing solution, then removing salts in the lignin condensate and forming a lignin fraction; Step III: carbonizing the lignin fraction and forming a carbide; Step IV: crushing the carbide; Step V: performing high-frequency heat treatment on the crushed carbide and obtaining carbon microparticles; and Step VI: re-crushing the carbon microparticles so that the carbon microparticles are micro-crushed to the nanometer range.

[0008] According to document WO2006 / 073460A2, fibers are spun from a supported array of nanotubes. The fibers are spun using a spinning shaft, for example, having a hooked end that contacts the supported nanotubes and twists some of them around each other to begin the fiber. As the twisted nanotubes detach from the support, the shaft moves away from and along the supported array in a controlled direction and at a controlled speed to twist and detach more nanotubes from the support, extending the length of the fiber. If the array is pretreated with a dilute polymer solution, the excess solution is squeezed out of the growing fiber during spinning, and the polymer can be cured at elevated temperature to obtain a strong nanotube composite fiber.

[0009] JP S63-270865A discloses a method for producing a filamentary far-infrared heating element, which is characterized in that a conductive resin containing a dispersed mixture of carbon particles and ceramic particles in a synthetic resin is melted and metered while heating and flowing, extruded into a sheath-like coating around a wound core yarn, and then cooled and solidified to continuously form a heating layer of the conductive resin around the core yarn. List of citationsPatent documents Patent Document 1: Patent Application Publication No. JP2009 - 242180A Patent Document 2: Patent Application Publication No. JP2010 - 042935A Patent Document 3: International Patent Publication No. WO2013 / 058382A1 Patent Document 4: Patent Application Publication No. JP2010 - 262912A Disclosure of the invention Problem to be solved by the invention

[0010] However, one problem is that the production of carbon material and carbon fibers requires a large number of manufacturing steps, which increases production costs. Furthermore, a heat-dissipating resistor component is required to create a heating element, and its tuning and manufacturing process are complicated.

[0011] The present invention has been designed to solve the above-mentioned problem and aims to provide an electric wire, a method for producing an electric wire and a heating element, and a heating device using the heating element, which can be easily manufactured while keeping the manufacturing cost low. Means of solving the problem

[0012] To achieve the object, a structure according to the invention comprises a carbonized material formed by carbonizing a silicon-containing plant raw material, continuous carbon fibers formed by mixing and spinning the carbonized material with a resin, a carbon fiber bundle formed by gathering the carbon fibers into a bundle, and a heating part that accommodates the carbon fiber bundle in a flexible tube. Effect of the invention

[0013] Due to the above-mentioned properties, the present invention can easily form a heating element because silicon is pre-incorporated into the carbon material as a resistance element, thus enabling low manufacturing costs and a simple manufacturing process. Furthermore, no toxic substances or the like are generated during the manufacturing process, thus making it ideal for industrial-scale production. Short description of the drawings Fig. 1 shows a process flow illustrating a manufacturing process of a heating device according to an embodiment. Fig. 2 shows a schematic structure of a plasma device according to Embodiment 1 of the embodiment. Fig. 3 shows a schematic structure of a plasma device according to Embodiment 2 of the embodiment. Fig.4 shows a relationship between a temperature of a carbonization source and a theoretical yield of carbonized material in the manufacturing process according to the embodiment. Fig. 5 shows a schematic view of the heating device according to the embodiment. Fig. 6 shows a schematic view of a part of the heating device according to the embodiment. Fig. 7 shows a schematic view of a part of the heating device according to the embodiment. Fig. Figure 8 shows an end face of the heating device in a section along a Fig. Line A - A shown in Figure 5. Fig. 9 shows a schematic view of a part of the heating device according to the embodiment. Fig. 10 shows a schematic view of a part of a carbon fiber according to the embodiment. Fig. 11A and Fig.11B shows a schematic view of a part of a manufacturing process of the carbon fiber according to the embodiment. Fig. 12 shows an electron microscope image of a carbonized material obtained by the manufacturing apparatus according to the embodiment. Fig. 13 shows an electron microscope image of the carbonized material obtained by the manufacturing apparatus according to the embodiment. Fig. 14 shows an electron microscope image of the carbonized material obtained by the manufacturing apparatus according to the embodiment. Fig. 15 shows a schematic view of the heating device according to the embodiment. Fig. 16 shows a schematic view of a part of the carbon fiber according to the embodiment. Fig. 17 is a schematic view showing a part of the manufacturing process of the carbon fiber according to the embodiment. Fig. 18 shows an electron microscope image of the carbon fiber obtained in the manufacturing process according to the embodiment. Fig. 19 shows an electron microscope image of the carbon fiber obtained in the manufacturing process according to the embodiment. Fig. 20 shows an electron microscope image of the carbon fiber obtained in the manufacturing process according to the embodiment. Fig. 21 shows a result of a semi-quantitative analysis using the X-ray intensity of a part of the carbon fiber according to the embodiment. Fig. 22 shows a process flow illustrating a manufacturing process of an electric conductor according to the embodiment. Fig. 23A to Fig. 23C show cross sections of the electrical conductor according to the embodiment. Fig. 24A and Fig.24B shows a schematic view of another embodiment of the electrical conductor according to the embodiment. Fig. 25A to Fig. 25F show a schematic view of other embodiments of the electrical conductor according to the embodiment. Fig. 26A to Fig. 26E shows a schematic view of other embodiments of the electrical conductor according to the embodiment. Fig. 27 is a block diagram showing a structure of a carbonized material manufacturing apparatus according to the embodiment. Fig. 28 shows a schematic structure of the carbonized material manufacturing apparatus according to the embodiment. Fig. 29 is a side view of the carbonized material manufacturing apparatus according to the embodiment. Fig.30 is a schematic view of parts of the carbonized material manufacturing apparatus according to the embodiment. Fig. 31 shows a schematic view of an impurity removing device according to the embodiment. Fig. 32 shows an electron microscope image of the carbonized material obtained by the manufacturing apparatus according to the embodiment. Fig. 33 shows an electron microscope image of the carbonized material obtained by the manufacturing apparatus according to the embodiment. Embodiments

[0014] Hereinafter, an electric wire, an electric conductor, a heating element, a method for manufacturing the heating element and the electric conductor, and a heating device using the heating element according to the present invention will be explained in more detail with reference to the drawings. It should be noted that the embodiments and drawings described below are only examples of some embodiments of the invention, are in no way intended to limit the invention to the structure of these embodiments, and can be modified as appropriate without departing from the scope of the present invention. Biomass material

[0015] The following explains a plant raw material, which is a biomass raw material for producing a carbonized material 19 according to the present embodiment. In the present invention, food scraps and plant raw materials from waste are used to produce the carbonized material 19. Plants, wood, and the like can be used as the plant raw material, but in particular, obtaining a raw material for producing the carbonized material 19 using wastes, such as waste from plant harvesting, as the plant raw material may be advantageous from a cost perspective. Table 1 Components of the plant raw material C N P P2O5 K K2O Ca Mg N / a rice straw 37,4 0,53 0,06 0,14 1,75 2,11 0,05 0,19 0,11 Wheat straw 40,3 0,67 0,08 0,18 1 1,21 0,21 0,11 0,06 Barley straw 41,8 0,58 0,08 0,18 1,4 1,69 0,29 0,1 - Rice bran 40,2 1,18 0,9 2,06 1,1 1,33 0,01 0,7 0,07 rice husks 34,6 0,32 0,03 0,05 0,31 0,37 0,01 0,07 0,13 buckwheat straw 40,3 1,08 0,21 0,48 3,13 3,77 1,35 0,14 - Soybean straw 44,5 1,23 0,12 0,28 0,75 0,9 1,39 0,64 0,2 Sweet potato tendrils 42,7 3,74 0,22 0,5 3 3,62 1 0,17 0,12 Beet leaves 39,8 3,33 0,27 0,62 4,35 5,24 1,7 0,8 0,49 Carrot leaves 41,4 2,63 0,25 0,57 4,2 5,06 0,56 0,19 0,51 corn stalks 43,8 0,92 0,09 0,21 1,32 1,59 0,24 0,12 - Sugarcane tips 46,1 0,99 0,1 0,23 1,2 1,45 0,37 0,12 0,18 Palm kernel flour 46,2 3,86 0,69 1,58 2,69 3,24 0,21 0,3 0,04 Peanut shells 51,1 0,75 0,02 0,06 0,47 0,57 0,17 0,05 0,05 Citrus fruit peels 44,5 0,76 0,05 0,11 0,58 0,7 0,4 0,06 0,07 Red cedar sawdust 51,1 0,07 - - - - - - - Bark of the Japanese larch 59,6 0,06 - - - - - - - Ginkgo leaves 50,3 0,71 0,06 0,15 0,29 0,35 1,5 0,23 0,06

[0016] Table 1 shows the components of the plant raw material. Table 1 shows the proportions of the components that make up the raw materials listed in the leftmost column, as percentages below. For example, rice straw contains 37.4% carbon (C), 0.53% nitrogen (N), 0.06% phosphorus (P), 0.14% phosphoric acid (P2O5), 1.75% potassium (K), 2.11% potassium oxide (K2O), 0.05% calcium (Ca), 0.19% magnesium (Mg), and 0.11% sodium (Na).

[0017] In this case, a porous plant-derived raw material containing plant-derived silicon shows no significant change even upon carbonization at high temperatures (from 300°C to 1000°C), and therefore, a pore arrangement can be preserved upon removal of silicon. In many plant-derived raw materials, cells are regularly arranged along the stem, and silica is usually deposited and accumulated on the cell wall.

[0018] In addition, there are narrow cell rows compressed with silica between the cell rows, and by removing silicon and the like after carbonization, a carbon material with a high specific surface area can be obtained. As mentioned above, a plant raw material with a high silica content of 13% to 35% is suitable. When carbon forms the electrically conductive material in the carbonized material 19 according to the present invention, silica corresponds to a resistance material, whereby a resistance element containing both materials can be easily manufactured in one process.

[0019] Examples of high-carbon plant raw materials are listed in Table 1. In addition to rice straw, these include wheat straw, barley straw, rice bran, rice hulls, buckwheat straw, soybean straw, sweet potato vines, beet leaves, carrot leaves, corn stalks, sugarcane tips, palm kernel meal, peanut shells, citrus peels, red cedar sawdust, Japanese larch bark, and ginkgo leaves. In addition, not only the waste but also the plants themselves can be used.

[0020] In bamboo, for example, fibers consist of cellulose, hemicellulose, and lignin, and the mineral content consists of iron, magnesium, calcium, manganese, copper, nickel, and the like. Furthermore, burning bamboo leaves can extract silanols (Si-OH), which form SiO4 during combustion, which can be extracted. Table 2 Composition of the plant raw material Water content Mineral content Fats lignin Hemicellulose Cellulose Other substances 8 - 10% 15 - 18% 0,1 - 0,5% 18 - 25% 16 - 20% 30 - 35% 5 - 10% Table 3 Inorganic chemical components of the plant raw material (wt%) SiO2 Al2O3 CaO Fe2O3 K2O MgO MnO Na2O 92,14 0,04 0,48 0,03 3,2 0,16 0,18 0,09

[0021] Tables 2 and 3 show the components and composition of a plant-based raw material that, among the carbon sources 9 listed above in Table 1, is most suitable for the inventive process for producing amorphous silicon dioxide or graphene. The bottom row of Table 2 shows the proportions of the components that make up the raw material as percentages. For example, the water content is 8% to 10%, the mineral content is 15% to 18%, the fat content is 0.1% to 0.5%, the lignin content is 18% to 25%, the hemicellulose content is 16% to 20%, the cellulose content is 30% to 35%, and the content of other substances is 5% to 10%. Thus, the main components that are converted to the carbonized material 19 are lignin, hemicellulose, and cellulose.

[0022] Table 3 lists the inorganic chemical components of the plant raw material shown in Table 2. The plant raw material shown in Table 2 contains 80 wt% organic substances such as cellulose and 20 wt% inorganic substances. The inorganic chemical components listed in Table 3 include 92.14 wt% SiO2, 0.04 wt% Al2O3, 0.48 wt% CaO, 0.03 wt% Fe2O3, 3.2 wt% K2O, 0.16 wt% MgO, 0.18 wt% MnO, and 0.09 wt% Na2O. The inorganic components of the plant raw material shown in Table 2 contain a large proportion of silicon dioxide (SiO2), as shown in Table 3. Carbonized material

[0023] The carbonized material 19, which is produced according to the embodiments 1 and 2 and obtained by a carbonization step S2, is Fig. 12 to Fig. 14 shown. Fig.Figure 12 shows an electron microscope image at 50,000 times magnification of the carbonized material 19 obtained in the carbonization step S2 and containing a weight fraction of 24 wt% silicon (Si). Fig. Figure 13 shows an electron microscope image at 100,000 times magnification of the carbonized material 19 obtained in the carbonization step S2. Fig. Figure 14 shows an electron microscope image at 100,000 times magnification of the carbonized material 19 obtained in the carbonization step S2 and containing 24 wt% of silicon (Si). Fig. In the electron microscope image shown in Figure 14, areas in the carbonized material 19 where the presence of silicon 66 can be detected are surrounded by black circles. Suitable carbonized material 19 is a carbonized material 19 with a silicon 66 weight fraction of approximately 18 wt% to 35 wt%.

[0024] In the Fig. 12 to Fig. In the carbonized material 19 shown in Figure 14, the carbon atoms are connected by sp2 hybrid orbitals via π bonds, forming a monoatomic film in the form of hexagonally arranged layers in a plane. It can be seen that the carbonized material 19 corresponds to a single layer produced in the carbonization step S2, contains extremely pure carbon, exhibits the presence of silicon 66, and contains a weight fraction of 24 wt% of silicon 66.

[0025] As in Fig.14, the carbonized material 19 obtained in the carbonization step S2 contains a large amount of silicon, and it is assumed that in the case of carbonization in an inert gas, the graphene is not greatly reduced but forms SiO2-x, forms a compound of the form -O-Si-O-R with an aromatic OH group or the like, and forms a lignin-polysaccharide complex, whereby the formation of a form of the type C / SiOx is likely.

[0026] Therefore, when a large amount of silicon 66 is contained in the carbonized material 19, an electrical resistance element is formed, whereby a carbon material containing a resistance element can be obtained only by the step of carbonizing the plant raw material, without forming a resistance element itself, whereby a heating element 51 can be manufactured at low production costs. In particular, a plant raw material having the properties described in Fig. 2 shown components for producing the heating element 51.

[0027] Furthermore, the Fig. 12 to Fig.14, the carbonized material 19 shown in a formation process for forming a framework, pores on the nano level and due to these pores, in particular when the carbonized material 19 is used in capacitors, batteries and the like, there is an increase in the energy density many times over, which also increases the electrical conductivity.

[0028] A so-called SQX analysis, a semi-quantitative analysis using X-ray intensity, revealed that the carbonized material 19 contains, in addition to carbon (C), silicon 66 (Si), potassium (K), calcium (Ca), and chlorine (Cl). Its function as a resistance element is due in particular to the high proportion of silicon 66 (Si) and calcium (Ca), which have low electrical conductivity. Heating device

[0029] Next, a heating device 50 is described with reference to Fig. 5 to Fig. 9 explained. Fig. 5A shows a side view of the heating device 50. The heating device 50 includes a power source connection part 52 formed at one end for connecting to a power source 54 and a connection end part 57 formed at the other end for performing a termination process. The heating device 50 has the heating element 51 between the power source connection part 52 and the connection end part 57.

[0030] The diameter (R3) of the Fig. 7 is approximately 6 mm and the length is 10 m.

[0031] Fig. Figure 5B is a circuit diagram illustrating the electrical connections. The power source 54 is shown with a single-layer 100 V AC power supply, however, a three-layer 200 V power supply or a DC power supply may also be used. As shown in Fig.As shown in Figure 5B, a resistance value (R) of a carbon fiber bundle 62 depends on a desired temperature of the heating element 51. At approximately 40°C to 60°C and an AC voltage of 100V input, the resistance value of the carbon fiber bundle 62 per 10m is 80 Ω to 120 Ω. However, power consumption may also be taken into account. Thus, in the present embodiment, a total resistance of the heater 50, which generates a temperature of 50°C as the maximum temperature, is approximately 107 Ω. The power consumption of the heater 50 is 93.5W.

[0032] Heat is generated primarily by the carbon fibers 63 described later, which generate heat in the carbon fiber bundle 62, in which the carbon fibers 63 are combined into a bundle. Furthermore, the heating element 51 has high strength, with a tensile strength of 200 N and a compressive strength of 200 N / square centimeter (cm*2). The carbon fibers 63 are continuous single fibers with a diameter of 6 µm to 9 µm.

[0033] In the heater 50, a later-described mesh-shaped electric conductor 53 made of a mesh-shaped electrically conductive material is connected to the power source connecting part 52 and the connecting end part 57, thereby covering a periphery of a later-described carbon fiber bundle cover 61.

[0034] The power source connecting part 52 and the connecting end part 57 are externally covered with an insulator, and the heater 50 is crimped to the carbon fiber bundle 62 and the electrical conductor 53 via a crimping part 55 of the connecting end part 57, thus electrically connecting them. Furthermore, in the heater 50, the electrical conductor 53 is connected to one end of the power source via the power source connecting part 52, and the other end of the power source is connected to the carbon fiber bundle 62, thereby supplying power to the heater 50 from the power source 54.

[0035] Fig. 6 shows a perspective view in which a part of an outer casing 56 of the heating element 51 is removed. Fig. 7 shows a perspective view in which a part of the outer sheath 56 and the carbon fiber bundle sheath 61 of the heating element 51 are removed. Fig.Fig. 8 shows an end face of the heating element 51 in a section along a part of a line A - A in Fig. 5A.

[0036] As in Fig. As shown in Figures 6 to 8, in the heating element 51, the carbonized material 19 produced by the above-described method is contained in the carbon fibers 63. The heating element 51 is formed with a carbon fiber bundle sheath 61 covered by an insulating material such as plastic, rubber, resin, or the like, which can bend around the periphery of the carbon fiber bundle 62 into which the carbon fibers 63 are bundled. In the present embodiment, the carbon fiber bundle sheath 61 is formed of silicone resin. The diameter (R1) of the carbon fiber bundle 62 is, as shown in Figure 5. Fig. 7 shown, 2 mm.

[0037] The heating element 51 further includes the mesh-shaped electrical conductor 53, which covers the periphery of the carbon fiber bundle sheath 61 and is made of a material with good electrical conductivity. By forming the mesh-shaped electrical conductor 53, its flexibility can be maintained, and even if one part is severed, the other parts will contact or join, thereby achieving a bend-flexible structure in which electrical connection breakage is unlikely to occur.

[0038] The heater 51 is formed with an outer casing 56 covered by an insulating material such as plastic, rubber, resin, or the like, which can bend around the periphery of the electrical conductor 53 and has excellent thermal conductivity. In the present embodiment, the heater 50 is assumed to be buried underground in the earth, in a road, and the like. Therefore, the outer casing 56 directly contacts the earth, water, or the like. Therefore, the heater 50 may preferably be formed of polyvinyl chloride, which has good thermal conductivity, abrasion resistance, waterproofness, and contractibility.In the heating element 51, the electrical conductor 53 is formed between the outer sheath 56 and the carbon fiber bundle sheath 61, and in addition to the electrical conductor 53, a gap 67 is formed, which forms an air layer and improves the temperature maintenance ability.

[0039] As in Fig. As shown in Figure 9, the heating element 51 includes the crimping part 55, in which the carbon fiber bundle 62, in which the carbon fibers 63 are bundled, and the electrical conductor 53 are fixed in an intermixed arrangement by crimping two arc-shaped metal fittings of the connecting end part 57. The crimping part 55 is covered and insulated from the outside by a resin with respect to the connecting end part 57, but an inside of the two is electrically connected. Example 1 Plasma device 10

[0040] In the following, a plasma device 10 according to Embodiment 1 will be described with reference to Fig. 2 explained. Fig. 2 shows a schematic structure of the plasma device 10 according to Embodiment 1. The plasma device 10 is mainly composed of an inert gas 6, a control device 20, a chamber 1 and a vacuum pump 30.

[0041] Argon was primarily used as the inert gas 6 stored in a gas cylinder, but helium, neon, nitrogen, and the like can also be used. The inert gas 6 can be filled into the chamber 1 from an inlet pipe 7 via a gas volume control device 21. The gas volume control device 21 can control a flow rate of the inert gas 6.

[0042] The chamber 1 is connected to a control valve 22, and the interior of the chamber 1 can be placed in a vacuum state by reducing the pressure using the vacuum pump 30. The inlet pipe 7 is connected to the chamber 1 and introduces the inert gas 6 into the interior of the chamber 1. Between the control valve 22 and the chamber 1, a relief valve 23 is provided, through which the interior of the chamber 1 can be relieved from the vacuum state to atmospheric pressure. In addition, a control valve 14 and a relief valve 15 are also provided between a discharge pipe 8 conducting the air from the interior of the chamber 1 and the vacuum pump 30, through which the interior of the chamber 1 can be relieved from the vacuum state to atmospheric pressure.

[0043] Furthermore, a temperature control device 24 is configured to control a high-frequency power source 4 and to regulate temperature maintenance, residence time, and the like inside the chamber 1. One method is to fill the plasma device 10 according to the present embodiment 1 with argon gas as the operating gas, which is the inert gas 6, under low pressure conditions close to a vacuum state, and apply a high current between electrodes, more specifically, between cathodes 2 and an anode 3, thereby generating a thermal plasma by means of arc discharge. A crucible 5 made of a carbon material is arranged between the cathodes 2 and the anode 3, and the carbon source 9 described later is located in this crucible 5.The carbon source 9 is carbonized by heating by the thermal plasma due to the arc discharge in a temperature range of 300°C to 1000°C for approximately 10 to 30 minutes. Embodiment 2Plasma device 100

[0044] In the following, a plasma device 100 according to Embodiment 1 will be described with reference to Fig. 3 explained. In Fig.3, parts having the same structure as in the plasma device 10 are designated by the same reference numerals, and explanations of parts with the same structure are omitted. The plasma device 100 is mainly composed of the inert gas 6, the control device 20, the chamber 1, and the vacuum pump 30. A major difference of the plasma device 100 is that in the thermal plasma generation process, the inert gas 6 is introduced for plasma generation, and a high-frequency magnetic field of 4 MHz is applied from a high-frequency power source 32 to a high-frequency coil 31, thereby generating the thermal plasma.

[0045] By using the plasma devices 10 and 100 described above, even lignin, which is difficult to decompose thermally, can be decomposed.

[0046] It should be noted that, in addition to the plasma devices mentioned above, thermal plasma can also be generated by dielectric barrier discharge, corona discharge, pulsed discharge or direct current discharge methods. Example 3

[0047] In the structure, parts having the same structure as those in Embodiment 1 are given the same reference numerals, and the explanation of parts having the same structure is omitted. Fig.15 shows a vessel 83 into which the carbon source 9 produced from the plant raw material in a pretreatment step S1 as explained in Example 1 and an antioxidant 70 are charged. In the present case, the carbon source 9 is preferably charged to a capacity of approximately 1 / 10 to 2 / 3 of the capacity of the vessel 83. In the pretreatment step S1, pulverization can be performed simply by a grinder or the like, without using a granulating agent.

[0048] In the present case, an oxidation inhibitor 70 can be any substance that enables combustion while suppressing the oxygen concentration to avoid oxidation during burning, and gases or liquids of the halides (carbon dioxide, nitrogen, Halon 2402, Halon 1121, Halon 1301) can be added for combustion.

[0049] Thereafter, the atmosphere inside a furnace 81 of a firing furnace 80 is heated to 2000°C or higher, and the carbon source 9 is fired under conditions of 20 atmospheres of pressure and temperatures of 400°C to 900°C for three hours. Example 4Process flow 1

[0050] With reference to Fig. 1, a manufacturing process of a method for manufacturing the heater 50 is explained.

[0051] Fig. 1 shows a process flow illustrating the manufacturing process according to the embodiment of Embodiment 2. The present process flow is explained using Embodiment 1, but the process flow can also be applied to Embodiment 1 or Embodiment 3 instead of Embodiment 2. Pretreatment step

[0052] First, in the pretreatment step S1, after the aforementioned drying of the plant raw material, the plant raw material is ground into powder, and the pulverized plant raw material and a granulating agent are mixed with water in a ratio of 10 to 1. The plant raw material is formed into a suitable size and mixed by kneading, and the mixture is finally heated on a drying device such as a hot plate at about 100°C to evaporate the water content and produce the carbon source 9. In this case, a grinder, a mixer, a mill, and the like can be used as the pulverization method. Carbonization step

[0053] Next, the carbonization step S2 is explained. In the pretreatment step S1, approximately 0.8 g of the carbon source 9 is filled into the crucible 5 and covered with a metallic mesh or the like. The crucible 5 is placed at a specific position where the above-described plasma devices 10 and 100 apply heat. The pressure in the chamber 1 is reduced to 80 Pa by the vacuum pump 30, the inert gas 6 is introduced into the chamber 1 at a flow rate of 8 to 10 ml / min, and the interior of the chamber 1 is maintained at a pressure of 1300 to 1500 Pa.

[0054] The applicant has completed the carbonation step S2 as described in Fig. 4, with a thermal plasma in a temperature range of 200°C to 1100°C, with intervals of 100°C each, and the temperature and the yield during carbonization of the carbon source 9 were determined. Fig.Figure 4 shows values ​​corresponding to the weight of the carbonized material 19 obtained from 0.8 g of carbon source 9. The highest yield was measured at 36% from 600°C to 700°C, and a comparatively high yield was achieved at temperatures from 300°C to 1000°C. The present measurement was carried out with rice straw, bran, palm kernel shells, rice husks, peanut shells, and the like, and similar results were obtained.

[0055] Furthermore, a carbonization step at temperatures ranging from 300°C to 1000°C can produce a carbonized material with a 24 wt% carbon and silicon 66 content, which is a suitable proportion for a heating element. Carbon has a resistivity of approximately 1.64 µΩ*m, and silicon 66 has a resistivity of approximately 1000 Ω*m. Therefore, silicon 66 accounts for a large portion of the resistance of the carbon fibers 63. Carbon fiber - manufacturing step

[0056] Next, a carbon fiber manufacturing step S3 for manufacturing the carbon fibers 63 using the carbonized material 19 obtained as described above will be explained by two methods according to Embodiment 4 and Embodiment 5, respectively. Example 5

[0057] First, with reference to Fig. 16 to Fig. 21 a process for spinning the carbon fibers 63 is explained. Fig. 17 shows a schematic view of a spinning method using a spinning device 40. Fig. 18 and Fig. 19 are electron microscope images showing a cross-sectional area when cutting through the carbon fiber 63. Fig. 20 is an electron microscope image showing a side surface of carbon fiber 63. Fig.Figure 21 shows an explanatory view of the results of a semi-quantitative analysis using the X-ray intensity of a part of the Fig. 18 shown carbon fiber 63 according to the embodiment.

[0058] The carbonized material 19 obtained in the previously described carbonization step (S2) was used to prepare a spinning starting liquid 41 for spinning. To prepare the spinning starting liquid 41, a dispersion solution is first prepared. In the dispersion solution, approximately 5 wt% to 20 wt% of the carbonized material 19 is added to a solvent selected from acetone, methyl isobutyl ketone, or dimethyl sulfoxide, and dispersed using ultrasonic dispersion, a mill, or the like. Other solvents such as water, sodium cholate, or sodium deoxycholate are also possible.

[0059] Next, a binder is added to the dispersion solution to obtain the spinning starting liquid 41. The spinning starting liquid 41 is extruded through an extruder 42, ejected from a thin nozzle 43 disposed in a coagulation liquid 45 of a coagulation bath 44, and hardened and formed into fibers through a chemical reaction between the coagulation liquid 45 and the aforementioned solvent. During this reaction, the solvent in the spinning starting liquid 41 is eluted into the coagulation liquid through contact with the coagulation liquid 45. This reaction is a solvent removal reaction, and the aforementioned solvent dissolves in the coagulation liquid.

[0060] Consequently, a liquid in which the previously described solvent is soluble is used for the coagulation liquid 45. For example, if polyvinyl alcohol is used for the binder, methanol is used as the coagulation liquid for dimethyl sulfoxide. Furthermore, if polyvinyl alcohol is used for the binder, caustic soda is used as the coagulation liquid for water. Furthermore, an organic solvent can also be used for the dispersant and the coagulation liquid. Furthermore, acetone can be used as the coagulation liquid when an epoxy resin is used as the binder.

[0061] For the binder, thermosetting resins such as epoxy resin, polyvinyl alcohol, nylon, rayon, acrylic, phenolic resin, melamine resin, urea resin, unsaturated polyester resin, alkyd resin, and thermosetting polyimide can be used, as well as thermoplastics such as polyethylene, polypropylene, polystyrene, acrylonitrile resin, butadiene resin, styrene resin, methacrylic resin, and vinyl chloride, as well as polyamide, polyacetal, polyethylene terephthalate, ultra-high molecular weight polyethylene, polycarbonate, polyphenylene sulfide, polyetheretherketone, polytetrafluoroethylene, polyetherimide, polyarylate, polyimide, and the like. The binder is blended in a ratio of 0.1% to 10% by weight with respect to 5% to 18% by weight of the carbonized material 19.

[0062] Furthermore, the ejected carbon fibers 63 are extended and conveyed out of the coagulation bath 44 by an upper roller 47 and a lower roller 46, and are finally rolled out as continuous carbon fibers 63 at a speed of 1.1 m / min to 2 m / min.

[0063] In addition, a dispersion solution containing 5 to 17% carbonized material 19, 0.1 to 10% urethane as a binder, and 82% of a mixture of methyl ethyl ketone, toluene, and cyclohexanone can be obtained, thus forming a dispersion solution with a high concentration of carbonized material 19. In this mixture, the amount of carbonized material 19 can also be adjusted depending on the resistance value of the heating element 51 to be ultimately produced.

[0064] In the above explanation, a method for producing the carbon fibers 63 by wet spinning was explained, however, the method for producing the carbon fibers 63 may also use a manufacturing method by dry spinning, melt spinning, air gap spinning or dry jet wet spinning.

[0065] In the case of melt spinning, the polymer is a polyester, nylon, polypropylene or the like and in the case of dry spinning, the polymer is an acetate, polyurethane, acrylic or the like.

[0066] It should be noted that even in the case where no polymer is used, production can be carried out by using an organic solvent as the dispersing agent and the coagulation liquid.

[0067] The carbon fibers 63 obtained by the method described above contain in some places, as shown in Fig. 16, Fig. 18 and Fig.19, in addition to carbon, silicon 66. In addition, Fig. 21 a result of a semi-quantitative analysis using the X-ray intensity of the substance of the Fig. 19. The carbon fibers 63 contain, in addition to carbon (C), silicon (Si) 66, calcium (Ca), aluminum (Al), and potassium (K). As shown in Fig. As shown in Figure 20, the diameter of the carbon fibers 63 is approximately 6 µm. In the carbon fiber bundle 62, approximately 100,000 to 120,000 of the carbon fibers 63 are bundled together.

[0068] In the present embodiment, approximately 110,000 carbon fibers 63 were used. The specific resistance of the carbon fiber bundle 62 is 2.92×10^(-3) (Ω m). The specific resistance of the carbon fibers 63 is 321 Ω m.

[0069] As in Fig.16, the graphene containing carbon 65 and silicon (Si) 66 is dissolved in an organic solvent with epoxy resin (resistivity of 10^(12-17) Ω m) as the above-mentioned elastic binder, the carbon fibers 63 are spun by wet spinning, and by gathering these carbon fibers 63 into a carbon fiber bundle 62, the flexible heating element 51 can be formed. Example 6

[0070] The carbon fibers 63 are mainly produced by impregnating the surface of a fiber base material 64 with the carbonized material 19 and adhering the carbonized material 19. The individual process steps are described below with reference to Fig. 10, Fig. 11A and Fig. 11B, explained in order. Fiber base material

[0071] The Fig.The fiber base material 64 shown in FIG. 10 can be formed from a carbon material, resin material, metallic material, ceramic material, and the like. When the fiber base material 64 is a carbon fiber, PAN-based carbon fibers can be produced by carbonizing polyacrylonitrile resin, and pitch-based carbon fibers can be produced by carbonizing pitch fibers obtained by using coal tar and heavy petroleum components as base materials. The thickness of the fiber base material 64 is from 5 μm to 15 μm, and the shape of the cross-sectional area of ​​the fiber base material 64 can be round, triangular, quadrangular, elliptical, and the like.

[0072] The carbonization process may include arc discharge, laser evaporation, chemical vapor deposition (CVD method), and the like. Of course, one of the methods previously described in Embodiment 1 to Embodiment 3 may also be used. By designing with the materials described above, both the formation of continuous individual fibers and the formation of stacks are possible. Adhesion process of the carbonized material

[0073] As in Fig. 11A, the carbonized material 19 is mixed with an adhesion solvent 93 described later, and the carbonized material 19 is dispersed in a weight concentration of approximately 10% in the adhesion solvent 93 within an adhesion layer 91 by means of an agitator, an ultrasonic vibrator, or a stirring machine to prepare an adhesion liquid 92.

[0074] Water, alcohols such as ethanol, methanol and isopropyl alcohol, and organic solvents such as toluene, acetone, tetrahydrofuran, methyl ethyl ketone, hexanes, n-hexane, diethyl ether, xylenes, methyl acetate and ethyl acetate can be used as the adhesion solvent 93.

[0075] Bundles of the fiber base material 64, in which the fiber base material 64 is combined into bundles, are introduced into the adhesion layer 91. Van der Waals forces act on the carbonized material 19, causing the carbonized material 19 to adhere to the bundles of the fiber base material 64.

[0076] It should be noted that the bundles of the fiber base material 64 to which the carbonized material 19 adheres are dried upon introduction into the adhesion liquid 92, thereby obtaining the carbon fibers 63. The resulting carbon fiber bundle 62 can also be finally formed into a tube using silicone resin or the like. Liquid impregnation process

[0077] As in Fig. 11B, in an adhesion device 90, in order to further enhance the strength and the like of the bundles of the fiber base material 64 to which the carbonized material 19 is adhered, the bundles of the fiber base material 64 may be impregnated with a resin impregnation liquid 95 of a resin impregnation layer 94, thereby covering a periphery of the fiber base material 64 with resin in the carbon fibers 63.

[0078] The bundles of the fiber base material 64 to which the carbonized material 19 adheres are immersed in the dissolved resin impregnation liquid 95 to impregnate the fiber base material 64 with resin.

[0079] For the resin material used for impregnation, for example, thermosetting plastics such as epoxy resin, phenolic resin, melamine resin, urea resin, unsaturated polyester resin, alkyd resin and thermosetting polyimide, and thermoplastics such as polyethylene, polypropylene, polystyrene, acrylonitrile resin, butadiene resin, styrene resin, methacrylic resin and vinyl chloride, as well as engineering plastics such as polyamide, polyacetal, polyethylene terephthalate, ultra-high molecular weight polyethylene, polycarbonate, polyphenylene sulfide, polyetheretherketone, polytetrafluoroethylene, polyetherimide, polyarylate, polyimide and the like can be used. Example 7 Manufacturing step of the heating device

[0080] Next, a manufacturing step of the heating device S4 will be described with reference to Fig. 5 to Fig. 8. The carbon fibers 63 obtained in the above-described carbonized material adhesion process and the liquid impregnation process are gathered in a bundle form into the carbon fiber bundle 62, the periphery of the carbon fiber bundle 62 is covered with a material such as a silicone resin and the like while being pulled apart, and the straight carbon fiber bundle sheath 61 covering the carbon fiber bundle 62 is rolled out.

[0081] Thereafter, while covering the periphery of the carbon fiber bundle sheath 61, inside which the carbon fiber bundle 62 is located, with the mesh-shaped electric conductor 53, the heating element 51 is formed in the shape of a straight tube by covering it with the outer sheath 56 and rolling it out.

[0082] Finally, the heating element 51 is cut to the required length of 10 m, and the previously described power source connecting part 52 and the connecting end part 57 are connected to the two ends of the heating element 51, whereby the heating device 50 can supply electric current to the heating element 51. Structure of the electrical conductorExample 8Flexible electrical conductor

[0083] In the present embodiment, with reference to Fig. 23A to Fig. 23C and Fig. 26A to Fig. 26E, a structure of a flexible electrical conductor 150 used for signal cables and power cables consisting of a graphene 113 in which the carbonized material 19 is further refined and the purity of the carbon is increased.

[0084] Fig.23A shows the single-core electrical conductor 150 containing the graphene 113, which is produced by a method explained later and contains carbon of a high purity.

[0085] Formed in the electrical conductor 150 is a carbon fiber bundle sheath 161 covered by an insulating material such as plastic, rubber, resin, or the like, which can bend around the periphery of a carbon fiber bundle 162 into which the carbon fibers 163 are bundled. In the present embodiment, the carbon fiber bundle sheath 161 is formed of silicone resin. The carbon fibers 163 are continuous single fibers with a diameter of 6 µm to 9 µm.

[0086] The diameter (R1) of the carbon fiber bundle 162 is, as shown in Fig.7, 2 mm. Furthermore, to form a corrosion- and wear-resistant structure, the electrical conductor 150 has an outermost sheath 165 made of polyvinyl chloride, polyethylene, or the like covering its outermost periphery. This makes the electrical conductor 150 a flexible and lightweight conductor with a low risk of conductor breakage. Note that the cable thickness of the electrical conductor 150 can be determined depending on the specific application or by the number of carbon fibers 163 accommodated in the carbon fiber bundle 162.

[0087] Fig. Figure 23B shows the electrical conductor 150, which has two of the Fig.23A, which has individual lines containing graphene 113, which is produced by a method explained later and contains carbon of a high purity, and inside which the two individual lines are arranged as twisted stranded wires.

[0088] In the electrical conductor 150, the carbon fiber bundle sheath 161 is formed, which is covered by an insulating material such as plastic, rubber material, resin or the like, which can bend around the circumference of carbon fiber bundles 162 into which the carbon fibers 163 are bundled, wherein in the present embodiment, the carbon fiber bundle sheath 161 is formed of silicone resin.

[0089] The diameter (R1) of the carbon fiber bundles 162 is, as shown in Fig.7, 2 mm. Furthermore, to form a corrosion- and wear-resistant structure, the electrical conductor 150 has an outermost sheath 165 made of polyvinyl chloride, polyethylene, or the like covering its outermost periphery. This makes the electrical conductor 150 a flexible and lightweight conductor with a low incidence of conductor breakage. Note that the cable thickness of the electrical conductor 150 can be determined depending on the specific application or by the number of carbon fibers 163 incorporated in the carbon fiber bundles 162.

[0090] Fig. Figure 23C shows the electrical conductor 150, which has two of the Fig.23A, which has individual lines containing graphene 113, which is produced by a method explained later and contains carbon of a high purity, and inside which the three individual lines are arranged as twisted stranded wires.

[0091] In the electrical conductor 150, the carbon fiber bundle sheath 161 is formed, which is covered by an insulating material such as plastic, rubber material, resin or the like, which can bend around the circumference of the carbon fiber bundles 162 into which the carbon fibers 163 are bundled, wherein in the present embodiment, the carbon fiber bundle sheath 161 is formed of silicone resin.

[0092] The diameter (R1) of the carbon fiber bundles 162 is, as shown in Fig.7, 2 mm. Furthermore, to form a corrosion- and wear-resistant structure, the electrical conductor 150 has an outermost sheath 165 made of polyvinyl chloride, polyethylene, or the like covering its outermost periphery. This makes the electrical conductor 150 a flexible and lightweight conductor with a low incidence of conductor breakage. Note that the cable thickness of the electrical conductor 150 can be determined depending on the specific application or by the number of carbon fibers 163 incorporated in the carbon fiber bundles 162.

[0093] Fig. 26A and Fig.26B shows a bundled cable 180 bundled as a temporarily wound cable 185 in which the carbon fiber bundles 162, into which the carbon fibers 163 are bundled, are temporarily wound by copper wires or a polymer. This allows a stranded wire and the like to be easily formed while simultaneously bundling the carbon fiber bundles 162. Fig. Figure 26A shows a side view of the temporarily wound cable 185 and Fig. 26B shows a view of a cross-sectional area of ​​the temporarily wound cable 185.

[0094] Fig. Figure 26C shows a view of a plurality of bundled cables 180, viewed from one side of the twist. Furthermore, Fig. 26D is a view of a cross-sectional area of ​​the plurality of twisted bundled cables 180.

[0095] Fig. 26E shows a cross-sectional area of ​​an electric conductor in which an insulating flexible sheath is additionally provided in a state in which the plurality of bundled cables 180 are twisted.

[0096] By forming the temporarily wound cables 185 in the manner described above, the strength of the electrical conductor 150 can be adjusted. Furthermore, the degree of cohesion between the carbon fibers 163 themselves can also be adjusted. Example 9Electrical conductor with contractibility

[0097] In the following, with reference to Fig. 24A and Fig. 24B and Fig. 25A to Fig. 25F, a structure of the flexible, contractible electrical conductor 150 used for signal cables and power cables made of the graphene 113 is explained, in which the carbonized material 19 is further refined in a process step of a purification step S2-1 described later, and the purity of the carbon is increased.

[0098] The electrical conductor 150 is formed in a thread-like manner by adding the graphene 113, which is refined in the purification step S2-1 and whose carbon purity is increased. Fig. 24A shows the thread-like shape of the electrical conductor 150, wherein the electrical conductor 150 contracts itself and can therefore conduct electrical current even when extended or contracted, thereby enabling use as signal cables and power cables in robots and drive devices, where problems due to conductor breakage could previously occur during extension or contraction. Fig. Figure 24B shows a cross-sectional area of ​​the electrical conductor 150 with the graphene 113 mixed therein.

[0099] Natural rubber, styrene rubber, butadiene rubber, chloroprene rubber, butyl rubber, nitrile rubber, ethylene-propylene rubber, chlorosulfonated polyethylene, acrylic rubber, urethane rubber, silicone rubber, fluororubber, hydrogenated nitrile rubber, epichlorohydrin rubber, and the like can be used as the rubber material 110. It should be noted that resins with contraction properties can also be used in addition to the rubber material 110.

[0100] In the present embodiment, the electrical conductor 150 in which the purity of graphene was increased by removing silicon by means of the purification step S2-1 described later, that is, the electrical conductivity was increased by increasing the carbon content, is used as the material having contractility.

[0101] The Fig. 24A and Fig. The electrical conductor 150 shown in Fig. 24B is formed by mixing the graphene 113 into the rubber material 110 and mixing the rubber material 110 and the graphene 113 by extrusion molding from a nozzle.

[0102] Fig. 25A to Fig. 25F show the electrical conductor 150 according to other embodiments. Fig. 25A shows a side surface of the electrical conductor 150 in a ribbon configuration, wherein the graphene 113 is applied to the surface of a platelet-shaped electrical conductor 120. Fig. 25B shows a cross-sectional area of ​​the plate-shaped electrical conductor 120. Inside the plate-shaped electrical conductor 120, a core material 122 is provided, which consists of the above-mentioned contractible rubber material or an electrically conductive rubber material.

[0103] In the plate-shaped electrical conductor 120, the excellent electrically conductive graphene 113 is fixed by adhesion to the surfaces of both side faces of the core material 122 or contained in the surfaces, whereby a contractible electrically conductive cable can be formed.

[0104] Fig. Figure 25C shows a woven electrical conductor 125 in which the plate-shaped electrical conductors 120 are woven together in a fabric form, forming a surface. The woven electrical conductor 125 is contractible and flexible, forming an electrically conductive element with a wide surface area.

[0105] Fig. Figure 25D shows a cross-sectional area of ​​the filamentary electrical conductor 150, wherein the graphene 113 is applied to the surface of a contractible filamentary electrical conductor 130. Provided inside the contractible filamentary electrical conductor 130 is a filamentary core material 132, which consists of the above-mentioned contractible rubber material or an electrically conductive rubber material.

[0106] In the contractile filamentary electrical conductor 130, the excellent electrically conductive graphene 113 is fixed by adhesion to the surfaces of both side faces of the filamentary core material 132 or contained in the surfaces, whereby the contractile electrical conductor 150 can be formed.

[0107] Fig. Figure 25F shows a mesh-shaped electrical conductor 135 in which a woven mesh is formed from the contractible, thread-like electrical conductors 130. The woven electrical conductor 135 is contractible and flexible, forming an electrically conductive element with a wide surface area. It should be noted that application to the previously described electrical conductor 53 is also possible.

[0108] Fig. Figure 25E shows a cross-sectional area of ​​the thread-like electrical conductor 150, in which the Fig. 25D mentioned, contractible, thread-like electrical conductor 130, additionally an insulating, above-mentioned insulating rubber material 133 is provided for sheathing.

[0109] Instead of the rubber material 110, a resin such as a contractible silicone resin or the like may also be used. Embodiment 10Device for producing carbonized material

[0110] In the present embodiment, with reference to Fig. 27 to Fig. 30, an apparatus for producing carbonized material 200 is explained, with which production on an industrial scale can be further advanced on the basis of the plasma devices 10 and 100 described above, used to produce the carbonized material 19.

[0111] In the carbonized material production apparatus 200, a plurality of receiving containers 205 made of a carbon material or a carbon composite material are provided inside a transparent quartz tube 203, mainly to enable industrial production, in which the carbon source 9 corresponding to the plant raw material is received.

[0112] First, with reference to Fig. 27 and Fig. 28, the carbonized material production apparatus 200 is explained. The transparent, cylindrical quartz tube 203 is provided between a left flange 231 and a right flange 232. Sealing and opening are possible through the left and right flanges 231 and 232, thereby maintaining the interior of the quartz tube 203 in a vacuum state and at low pressure. Furthermore, the quartz tube 203 is detachably formed from an open end of the left and right flanges 231 and 232, respectively. The left and right flanges 231 and 232 have a water-cooled cooling function.

[0113] It should be noted that the quartz tube 203 may be fixed by a method in which it is removably clamped and fixed from both sides of the left and right flanges 231 and 232.

[0114] As in Fig. As shown in Figure 27, the right flange 232 is connected to a pipe connected to a control valve 224 that controls the flow rates of an inert gas 217 and a fuel gas 218, and the interior of the quartz tube 203 can thus be filled with the inert gas 217 and the fuel gas 218, respectively. Furthermore, the right flange 232 is connected to a rough vacuum pressure gauge 219, and the left flange 231 is connected via a filter 221 to a pressure control valve 222 and the control valve 224.

[0115] A control device 210 is designed to control the pressure inside the quartz tube 203 by means of a dry pump 223 connected to the pressure control valve 222 and the control valve 224.

[0116] As in Fig. 27 and Fig. 28, the apparatus for producing carbonized material 200 comprises a high-frequency coil 240 and an electric furnace 250, which enable heating to different temperatures and allow to extract not only carbon but also silicon dioxide from the carbon source 9, which corresponds to the plant raw material, and which can also be used in the above-mentioned purification step.

[0117] The high-frequency coil 240 is shaped to surround a periphery of the quartz tube 203, and a coil support 242 supporting a coil 243 is attached to a drive device 1 (214). This drive device 1 (214) performs a movement in the X direction, or the negative X direction, along rails 236. A motor is used as the drive device 1 (214). Note that a linear actuator or the like can be used instead of the motor.

[0118] The principle and the manufacturing process are the same as those of the above-explained plasma device 100 according to Embodiment 2, but there is a difference in that the high-frequency coil 240 is movable to the X direction or the negative X direction, and since in a single structure the plurality of receiving containers 205 accommodating the carbon source 9 can be carbonized one after the other, a large amount of the carbon source 9 can be carbonized in a single process. Mainly, use in the manufacturing process in the aforementioned carbonization step in S2 in Fig. 1.

[0119] In addition, the high-frequency coil 240 includes a cover plate 241 for reducing an influence of the electromagnetic waves emanating from the coil 243 in the vicinity of the coil 243.

[0120] In the device for producing carbonized material 200, a thermal plasma is generated by introducing the inert gas 217 and applying a high-frequency magnetic field of 4 MHz from a high-frequency power source 212 to the high-frequency coil 240 and at temperatures of 300°C to 1000°C, as in Fig. 4, a comparatively high yield was achieved.

[0121] By using the above-described high-frequency coil 240 and the inert gas 217, even lignin, which is difficult to decompose thermally, can be decomposed. Furthermore, no toxic substances or the like are generated during the production process, making it ideal for industrial-scale production.

[0122] It should be noted that, in addition to the plasma devices mentioned above, thermal plasma can also be generated by dielectric barrier discharge, corona discharge, pulsed discharge or direct current discharge methods.

[0123] A water-cooled cooling device 213 is provided in the high-frequency power source 212 for cooling the coil 243 and the power source. Furthermore, a filter 221 made of nonwoven fabric, cotton, paper, or the like is provided in the quartz tube 203 to prevent the dry pump 223 from being influenced by tar components or the like generated during combustion.

[0124] Furthermore, as in Fig. 28 shown, thermocouples 235 of a Fig. 27 is provided near each receiving container 205. This allows the control device 210 to perform carbonization at a desired temperature using information obtained from the temperature control device 211. In particular, temperature control is important because the yield varies with temperature. In addition, by controlling the temperature, the carbonized material production device 200 can not only extract the carbonized material 19 from the plant raw material, but can also extract a large amount of silicon dioxide.

[0125] The electric furnace 250 is shaped to surround a periphery of the quartz tube 203 and is attached to a drive device 2 (216). This drive device 2 (216) performs a movement in the X direction or the negative X direction along the rails 236. A motor is used as the drive device 2 (216). Note that a linear actuator or the like can be used instead of the motor.

[0126] The electric furnace 250 can raise the temperature to near 2000°C by the heat of a heating element designed to utilize Joule heat and can perform a firing process in the quartz tube 203 during the refining of the carbon source 9 and the carbonized material 19 with the supply of the fuel gas 218. In addition, the fuel gas 218 is used to support combustion, and oxygen and the like are conceivable as the fuel gas 218. The fuel gas 218 is used in the process flow mainly in the Fig. 22 is used and its use occurs during combustion in the range of 1000°C.

[0127] It should be noted that the electric furnace 250 can be a low-frequency induction furnace utilizing electromagnetic induction currents, a high-frequency induction furnace utilizing eddy currents, an arc furnace utilizing extracted high heat, and the like. Furthermore, the electric furnace 250 can remove substances such as CO2 by combustion while supplying oxygen as the fuel gas 218, and can clean the originally transparent quartz tube 203 by removing carbonized material adhering thereto. This can prevent a temperature drop of the thermal plasma caused by the high-frequency coil 240.

[0128] Next, the quartz tube 203 and the receiving containers 205 are described with reference to Fig. 28 to Fig. 30 explained.

[0129] As in Fig. 29 and Fig. As shown in Figure 30, the receiving containers 205 for receiving the carbon source 9 and the carbonized material 19 are open at the top and formed of a box-shaped carbon material. Specifically, the carbonized material production apparatus 200 provides a plurality of receiving containers 205 to enable the carbonization of larger quantities of material compared to the previously explained plasma devices 10 and 100.

[0130] The receptacles 205 are mounted on a support base 206, on the upper surface of which are provided a plurality of upper sections 208, whose rod-shaped parts protrude at four corners, and on the lower surface of which are provided a plurality of plate-shaped lower sections 207 protruding upward at both ends. Holes are provided downwardly on the receptacles 205 in the same position as the upper sections 208, into which the parts of the upper sections 208 can be inserted. The upper sections 208 are fitted into these holes, thereby securing the receptacles 205 to the support base 206.

[0131] The support base 206, on which the receptacles 205 are mounted, is fitted into the lower sections 207 for support on a base base 202, along base base grooves 204 provided as grooves on the base base 202. A plurality of base base grooves 204 are provided offset by a length of Y1 in the width direction, so that the receptacles 205 can be arranged offset. Furthermore, the receptacles 205 are not only offset in the width direction, but also, as shown in Fig. 28, spaced apart by a certain distance X1 in the X direction.

[0132] By spacing the receptacles 205 in the Y1 direction and the X direction, it is possible to prevent, to the greatest extent possible, the receptacles 205 that are not to be carbonized from being affected by the plasma heat during carbonization. Furthermore, to enable temperature control, a thermocouple receiving space 209 is provided on the base pedestal 202 near the base pedestal grooves 204, which serves as a space for mounting the thermocouples.

[0133] As in Fig. As shown in Figure 29, the quartz tube 203 is formed as a circular tube with an outer diameter of approximately 125 mm made of transparent quartz. Furthermore, a support base 206 is formed with a width that allows the receiving containers 205 to be mounted below the center of the interior chamber of the quartz tube 203.

[0134] The device for producing carbonized material 200 is designed for producing carbon, but depending on the temperature conditions, it is also possible to extract silicon dioxide from biomass material, particularly allowing the production of amorphous silicon dioxide. Furthermore, not only the aforementioned carbonization step S2 but also the purification step S2-1 can be carried out using an electric furnace. Therefore, various processes can be carried out with the same device while maintaining temperature control. Embodiment 11Impurity removal device

[0135] Fig. 31 shows an example of an impurity removal device 40 that removes silicon dioxide (silicon) from the carbonized material 19 obtained by carbonizing the carbon source 9 by the above-mentioned plasma devices 10 and 100, thereby obtaining the graphene 113.

[0136] A heating furnace 41 can heat a furnace 42 to high temperatures of approximately 2000°C. A large crucible 50 is covered with a lid 51, and a small crucible 60 and activated carbon 53 are located inside a vessel portion 52. A vessel portion 62 of the small crucible 60 contains the carbonized material 19 and potassium hydroxide (KOH) 18 above it, and a lid 61 is provided. Stable fine ceramic materials and the like are conceivable as materials for the small crucible 60 and the large crucible 50; for example, aluminum oxide Al2O3 can be used. Embodiment 12Method for producing the electrical conductor Process flow 2

[0137] With reference to Fig. 22, a manufacturing process of a method for producing graphene 113 using the carbonized material manufacturing apparatus 200 is explained. Note that the pretreatment step S1 is the same as that in the above-described process flow 1 according to Embodiment 4, and therefore, the explanation is omitted.

[0138] In the following, the carbonization step S2 is described in the case of using the Fig. 27 to Fig. 30 according to the present embodiment. In the pretreatment step S1, the carbon source 9 is filled into receiving boxes 205 and covered with a metallic mesh made of stainless steel or the like. The plurality of receiving boxes 205 are staggered at specific positions to which the above-described carbon material producing apparatus 200 applies heat. The pressure in the quartz tube 203 is reduced to 80 Pa by the dry pump 223, the inert gas 217 is introduced into the quartz tube 203 at a flow rate of 8 to 10 ml / min, and the interior of the chamber 1 is maintained at a pressure of 1300 to 1500 Pa.

[0139] The applicant has completed the carbonation step S2 as described in Fig. 4, with a thermal plasma in a temperature range of 200°C to 1100°C, with intervals of 100°C each, and the temperature and the yield during carbonization of the carbon source 9 were determined. Fig. Figure 4 shows values ​​corresponding to the weight of the carbonized material 19 obtained from 0.8 g of carbon source 9. The highest yield was measured at 36% from 600°C to 800°C, and a comparatively high yield was achieved at temperatures from 300°C to 1000°C. The present measurement was carried out with rice straw, bran, palm kernel shells, rice husks, peanut shells, and the like, and similar results were obtained.

[0140] Next, the purification step S2 - 1 is explained. The carbonized material 19 obtained as described above and the potassium hydroxide (KOH) 18 are mixed in a weight ratio of one to five and introduced into the vessel part 62 of the Fig. 31, onto which the lid 61 is placed. In addition, the small crucible 60 is placed inside the Fig. 31, and the activated carbon 53 is filled around the small crucible 60. The activated carbon 53 is filled to prevent oxygen from penetrating the interior of the small crucible 60. The electric furnace 250 heats the interior of the quartz tube 203 to temperatures of up to about 950°C and performs a firing process of approximately two to three hours.

[0141] Potassium hydroxide 18 promotes the removal of silicon and is therefore used to increase the yield of graphene 113. Examples of basic solutions include alkali metal hydroxides such as sodium hydroxide and lithium hydroxide, alkaline earth metal hydroxides such as magnesium hydroxide and calcium hydroxide, alkali metal oxides such as sodium oxide and potassium oxide, alkaline earth metal oxides such as magnesium oxide and calcium oxide, alkali metal sulfides such as sodium sulfide and potassium sulfide, and alkaline earth metal sulfides such as magnesium sulfide and calcium sulfide. Furthermore, uncarbonized lignin can be removed by acid, specifically, by one, two, or more acids selected from the group consisting of hydrochloric acid, sulfuric acid, PTSA, and aluminum chloride.

[0142] In the carbonized material 19 reacted with potassium hydroxide, silicic acid reacts with the potassium hydroxide 18 to form potassium silicate. The remaining, water-soluble potassium hydroxide (KOH) 18 ( Fig. 31) and potassium silicate are dissolved in water, the solution is applied to filter paper, and silicon and silicon dioxide are removed by passing through a filter device under vacuum and reduced pressure, respectively. This allows the final product, graphene 113, to be produced in purification step S2-1 after drying, with a weight of approximately 1 / 8 to 1 / 10 of the initial plant-based raw material during granulation.

[0143] Fig. Figure 32 shows an electron microscope image of graphene 113 from which impurities have been removed and in which the purity of the carbon has been increased, at 50,000 times magnification. Fig.Figure 33 shows an electron microscope image of graphene 113 from which impurities have been removed and the carbon purity has been increased, at 100,000x magnification. As shown, tiny pores are formed at the nanoscale, which is why the electrical conductivity can be increased by adsorbing a metallic substance onto graphene 113. For example, the electrical conductivity can be increased by adsorbing a metal from metallic ions such as copper ions, aluminum oxide ions, and the like.

[0144] In the carbon fiber manufacturing step S3, the carbon fibers are manufactured using the same step as in S3 described above, except that the graphene 113 treated in the previously described purification step S2-1 is used for the carbonized material 19, thereby achieving excellent electrical conductivity. The electrical conductor 150 manufactured in the carbon fiber manufacturing step S3 is essentially the same as the electrical conductor 150 explained in Example 8.

[0145] Next, a manufacturing step of an electrically conductive member S5 will be explained, in which, when applied to electrical cables such as signal cables, power lines, and the like, it is possible to add a step of covering single wires and a step of forming stranded wires as shown in Embodiment 8. Furthermore, in the manufacturing step of the electrically conductive member S5, when using the mesh-shaped electrical conductor 135 and the woven electrical conductor 125 having contractibility as shown in Embodiment 9, a step of attaching a contractible insulating layer or the like to the surface from above may be provided.

[0146] It should be noted that in the electrical conductor 150 described above, the graphene 113 made from the plant raw material was used, but carbon materials or carbon nanotubes made from a mineral or a petroleum derivative can also be used.

[0147] Furthermore, in addition to the carbonized material 19 containing silicon made from the plant raw material, the heating element 51 can also be manufactured by adding silica or resin to the carbon material or carbon nanotube made from a mineral or a petroleum derivative to increase the electrical resistance.

[0148] Please note that the numerical value at the right edge of the electron microscope images corresponds to the value obtained by summing all 10 intervals, and that one interval corresponds to one-tenth of the numerical value shown at the right edge. For example, if the numerical value at the right edge is 500 nm, one interval is 50 nm. List of reference symbols 1 chamber 2 cathodes 3 Anode 4, 32 High frequency power source 5 jars 6, 217 inert gas 7 Inlet pipe 8 Discharge pipe 9 Carbon source 10, 100 plasma devices 14, 22, 224 control valves 15, 23 drain valves 19 carbonized material 20 Control device 21 Gas volume control device 30 vacuum pump 31 High frequency coil 80 kiln 81 Oven 50 Heating device 51 Heating element 52 Power sources - connecting part 53 electrical conductor 54 Power source 55 Crimp - Part 56 outer sheath 57 Connecting end part 61, 161 Carbon fiber bundle sheathing 62, 162 carbon fiber bundles 63 Carbon fiber 64 fiber base material 65 Carbon 66 Silicon 67 space 70 Oxidation inhibitor 83 boilers 91 Adhesion layer 92 adhesion fluid 93 Solvents 94 Resin impregnation layer 95 Resin impregnation fluid 110 rubber material 113 graphs 120 plate-shaped electrical conductor 122 nuclear material 125 woven electrical conductor 130 thread-like electrical conductor 132 thread-like core material 133 insulating rubber material 135 reticulated electrical conductor 150 electrical conductors 161 Carbon fiber bundle sheathing 165 outermost sheath 180 bundled cables 185 temporarily wound cable 200 Device for producing carbonized material 202 base socket 203 quartz tube 204 base socket grooves 205 recording boxes 206 Support base 207 lower sections 208 upper sections 209 Recording Room 210 Control device 211 Temperature control device 212 High frequency power source 213 Cooling device 214 Drive device 1 215 Power sources - Control device 216 Drive device 2 218 Fuel gas 219 Vacuum pressure gauge 221 filters 223 dry pump 231 Left flange 232 Right flange 235 thermocouple 236 rails 240 high frequency coil 241 Cover plate 242 spool support 243 coil 250 electric oven S1 Pretreatment step S2 Carbonization step

Claims

[1] A heating device (50) in which a heating element (51) comprising a carbonized material (19) formed by carbonizing a silicon-containing plant raw material, continuous carbon fibers (63) formed by mixing and spinning the carbonized material with a resin, a carbon fiber bundle (62) formed by gathering the carbon fibers into a bundle, and a heating part that accommodates the carbon fiber bundle (62) in a flexible tube (61) is used, characterized by , that a periphery of the heating part is covered with a mesh-shaped electrical conductor (53), the electrical conductor and the carbon fiber bundle are electrically connected to one end of the heating element via a connecting part (57), a circumference of the electrical conductor is additionally covered with a flexible, thermally conductive and insulating outer sheath (56), and a feed terminal (52) is provided which supplies current to another end of the heating element. [2] Heating device according to claim 1, characterized by that the carbonized material (19) contains a weight fraction of 18 wt% to 35 wt% of silicon. [3] The heating device according to claim 1 or 2, characterized by that an air layer is provided between the tube (61) and the outer casing (56) in addition to the electrical conductor. [4] A method for producing a heating element (51), comprising: a pretreatment step (S1) in which a carbon source (9) is obtained by drying and pulverizing a silicon-containing plant raw material, a carbonization step (S2) for producing a carbonized material (19) by carbonizing the carbon source, which comprises a heating step in which an inert gas (6) is introduced into a chamber (1) and the carbon source is heated in the chamber in a plasma atmosphere, a carbon fiber manufacturing step (S3) in which the silicon-containing carbonized material is mixed with a resin and dissolved in a solvent, and continuous carbon fibers (63) are obtained through a nozzle, and a tube-containing step in which the carbon fibers combined into a bundle (62) are contained in a flexible, heat-conducting and insulating outer sheath (56). [5] A method for producing a heating element (51), comprising: a pretreatment step (S1) in which a carbon source (9) is obtained by drying and pulverizing a silicon-containing plant raw material, a carbonization step (S2) for producing a carbonized material (19) by carbonizing the carbon source, which comprises a heating step in which an inert gas (6) is introduced into a chamber (1) and the carbon source is heated in the chamber in a plasma atmosphere, a carbon fiber manufacturing step (S3) in which carbon fibers (63) are obtained by adhering the silicon-containing carbonized material to a surface of a single-fiber base material (64), and a tube-containing step in which the carbon fibers combined into a bundle (62) are contained in a flexible, heat-conducting and insulating outer sheath (56). [6] A method for producing an electrical conductor (150), comprising: a pretreatment step (S1) in which a carbon source (9) is obtained by pulverizing a plant raw material, a carbonization step (S2) in which a carbonized material is obtained by carbonizing the carbon source, and a purification step (S2-1) in which impurities, including silicon dioxide, are removed from the carbonized material obtained in the carbonization step, characterized by , that the carbonization step (S2) is obtained by a heating step in which an inert gas (6) is introduced into a chamber (1) and the carbon source in the chamber is heated in a plasma atmosphere, and the method further comprises: a carbon fiber manufacturing step (S3) in which the carbonized material obtained in the cleaning step (S2-1) is mixed with a resin, dissolved in a solvent, and continuous carbon fibers (163) are obtained through a nozzle, and a tube-containing step in which the carbon fibers combined into a bundle (162) are contained in a flexible, insulating outer sheath (165).

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