Composition for electrode bar, electrode bar, method for manufacturing electrode bar, and method for producing liquid metal

Abstract

One embodiment of the present invention relates to a composition for an electrode bar for manufacturing an electrode member of an electric furnace, in which the composition may comprise a first carbon-based material comprising artificial graphite, an antioxidant material, and a binder, the antioxidant material comprises a material having a higher reactivity with oxygen (O) than carbon (C). According to an embodiment of the present invention, oxidation resistance of an electrode member provided on an electrode bar of an electric furnace can be improved, and thus, a rate at which the electrode member is oxidized can be reduced. Therefore, a pencil stub in which the diameter of the electrode member is reduced due to an oxidation reaction can be suppressed.

Description

Technical Field

[0001] The present invention relates to a composition for an electrode rod, an electrode rod, a method for manufacturing an electrode rod, and a method for manufacturing liquid metal, and more particularly, to a composition for an electrode rod, an electrode rod, a method for manufacturing an electrode rod, and a method for manufacturing liquid metal capable of improving the oxidation resistance of an electrode member. Background Art

[0002] Recently, in response to the climate change crisis, carbon neutral technology is emerging that reduces actual carbon dioxide emissions to zero by reabsorbing carbon dioxide emitted by individuals, companies, and organizations. As a result, the steelmaking industry is researching and developing hydrogen reduction ironmaking process technology, in which hydrogen is used instead of fossil fuels that produce carbon dioxide to produce direct reduced iron, and then the direct reduced iron is used to produce iron. After the commercialization of hydrogen reduction ironmaking process technology, the electric furnace method can be used to replace not only the blast furnace process that produces a large amount of carbon dioxide, but also the basic oxygen furnace process.

[0003] An electric furnace is a device that supplies power to an electrode rod and utilizes heat and an electric arc generated by the electrode rod to melt an iron raw material such as reduced iron or scrap. In addition, there is an electric furnace that uses a self-baking electrode rod as an electrode rod. The self-baking electrode rod is an electrode rod prepared by introducing a composition for an electrode rod containing carbon (C) into a cylindrical shell installed to be inserted into an electric furnace, and then firing the composition for an electrode rod by using heat inside the electric furnace and power supplied to the shell.

[0004] Meanwhile, the electrode rod may be oxidized by air introduced into the electric furnace and oxidizing gas generated therein. Then, the oxidation reaction may cause penciling in which the diameter of the electrode rod is reduced.

[0005] When the electrode rod is penciled, heat generation in the electrode rod is reduced, and the area around the electrode rod where the arc is generated is reduced. Therefore, the efficiency of the operation of dissolving the iron raw material to produce the liquid metal may be reduced. In addition, as the electrode rod is penciled, the risk of the electrode rod breaking during operation increases, and the breakage of the electrode rod becomes a factor of stopping the operation or reducing the operation efficiency.

[0006] In order to reduce the pencil-like appearance of the electrode rod, the amount of the electrode rod composition introduced into the housing of the electrode rod needs to be increased, or the injection cycle needs to be shortened. In this case, there is a problem of increased cost for producing the electrode rod composition.

[0007] (Prior art literature)

[0008] (Patent Document 1): Korean Patent Registration No. 10-2094053 Summary of the invention

[0009] Technical issues

[0010] The present invention provides a composition for an electrode rod capable of reducing the oxidation rate of an electrode member, an electrode rod, a method for manufacturing an electrode rod, and a method for manufacturing a liquid metal.

[0011] The present invention provides a composition for an electrode rod capable of improving electrical characteristics, an electrode rod, a method for manufacturing an electrode rod, and a method for manufacturing liquid metal.

[0012] Technical Solution

[0013] One embodiment of the present invention is a composition for an electrode rod for manufacturing an electrode member of an electric furnace, wherein the composition may include a first carbon-based material including artificial graphite, an antioxidant material including a material having a higher reactivity with oxygen (O) than carbon (C), and a binder.

[0014] In the entire composition for an electrode rod, the first carbon-based material may be contained in an amount of 50 to 65 wt %, the antioxidant material may be contained in an amount of 1 to 7 wt %, and the binder may be contained in an amount of 30 to 43 wt %.

[0015] The composition for an electrode rod may include a second carbon-based material including at least one of natural graphite and coke.

[0016] In the entire electrode rod composition, the content of the first carbon-based material may be 50 wt % to 60 wt %, the content of the antioxidant material may be 1 wt % to 5 wt %, and the content of the binder may be 30 wt % to 40 wt %, and the content of the second carbon-based material may be 1 wt % to 5 wt %.

[0017] The composition for an electrode rod may use a scrap containing artificial graphite as the first carbon-based material.

[0018] The antioxidant material may include at least one of metal Al and metal Si.

[0019] The first carbon-based material and the second carbon-based material may be provided in a solid state including a plurality of particles, the antioxidant material may be provided in a liquid state, and the antioxidant material may be coated on surfaces of particles of the first carbon-based material.

[0020] One embodiment of the present invention is an electrode rod installed so that a portion of it is inserted into the body of an electric furnace, wherein the electrode rod includes a shell and an electrode member, the shell having an internal space formed by extending in one direction, the electrode member being formed by inserting a green block into the shell, thereby firing the green block, and being formed so that a portion of it is positioned inside the shell and the rest protrudes to the outside of the lower side of the shell, the green block containing a first carbon-based material, an antioxidant material and a binder, the first carbon-based material containing artificial graphite, the antioxidant material containing a material having a higher reactivity with oxygen (O) than carbon (C).

[0021] The antioxidant material may include at least one of metal Al and metal Si.

[0022] The briquette may include a second carbon-based material including at least one of natural graphite and coke.

[0023] A method for manufacturing an electrode rod according to one embodiment of the present invention may include: manufacturing a green block, the green block comprising a first carbon-based material, an antioxidant material and a binder, the first carbon-based material comprising artificial graphite, the antioxidant material having a higher reactivity with oxygen (O) than carbon (C); inserting the green block into a shell of an electrode rod installed to be inserted into a main body of an electric furnace; and forming an electrode member by firing the green block using heat inside the main body and electricity supplied to the shell.

[0024] Manufacturing the compact may include preparing a composition for an electrode rod by mixing a first carbon-based material, an antioxidant material, and a binder, and assembling the composition for an electrode rod.

[0025] Manufacturing the compact may include coating an antioxidant material on surfaces of particles of a first carbon-based material, preparing a composition for an electrode rod by mixing the first carbon-based material coated with the antioxidant material and a binder, and assembling the composition for an electrode rod.

[0026] Preparing the composition for the electrode rod may include preparing a second carbon-based material including at least one of natural graphite and coke, and mixing the first carbon-based material, an antioxidant material, a binder, and the second carbon-based material.

[0027] Preparing the composition for the electrode rod may include preparing a second carbon-based material including at least one of natural graphite and coke, and mixing the first carbon-based material coated with the antioxidant material, a binder, and the second carbon-based material.

[0028] According to one embodiment of the present invention, a method for manufacturing liquid metal includes: inserting raw materials into a main body of an electric furnace; inserting a briquette into a shell of an electrode rod installed so that a portion thereof is positioned inside the main body, the briquette comprising a first carbon-based material, an antioxidant material and a binder, the first carbon-based material comprising artificial graphite, the antioxidant material having a higher reactivity with oxygen (O) than carbon (C); forming an electrode member by firing the briquette inside the shell, wherein a portion of the electrode member is positioned inside the shell and the rest protrudes to the outside of the lower side of the shell; and melting the raw materials by supplying electricity to the electrode rod to generate heat.

[0029] The method may further include first reacting an antioxidant material contained in the electrode member with oxygen (O) instead of reacting carbon (C) contained in the electrode member with oxygen (O).

[0030] Reacting the antioxidant material with oxygen (O) may include reacting at least one of Al and Si included in the antioxidant material with oxygen (O).

[0031] The briquette may include a second carbon-based material including at least one of natural graphite and coke.

[0032] The raw material may comprise hydrogen direct reduced iron reduced by hydrogen.

[0033] Beneficial Effects

[0034] According to the embodiment of the present invention, the oxidation resistance of the electrode member set in the electrode rod of the electric furnace can be improved, and thus, the rate at which the electrode member is oxidized can be reduced. Therefore, pencil-like reduction in the diameter of the electrode member due to oxidation reaction can be suppressed.

[0035] In addition, the reduction in the area of ​​the region where heat is generated in the electrode member and the decrease in the temperature of the region due to penciling or the reduction in the region where arcs are generated around the electrode member can be suppressed. Therefore, when liquid metal is produced by melting raw materials with heat and arcs generated by the electrode member, the operating efficiency can be improved.

[0036] In addition, since the oxidation resistance of the electrode member is improved, the life of the electrode member can be improved. Therefore, during the operation of the electric furnace, the amount of the electrode rod composition introduced into the housing to form the electrode member can be reduced, and the introduction period can be extended. Therefore, due to the introduction of the electrode rod composition, there is an effect of reducing costs.

[0037] In addition, the resistivity of the electrode member can be reduced. Therefore, the efficiency of generating heat and arc by the power supplied in the electrode rod can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a diagram schematically showing an electric furnace provided with an electrode rod according to one embodiment of the present invention.

[0039] Figure 2 is a sectional view showing a state in which an electrode rod according to one embodiment of the present invention is installed to be inserted into a main body of an electric furnace.

[0040] Figure 3 (a) is a photograph of the electrode member of the electrode rod before being pencil-shaped, and Figure 3 (b) is a photograph of the electrode structure after being pencil-shaped.

[0041] Figure 4 (a) shows the results of X-ray diffraction (XRD) analysis of anthracite, and Figure 4 (b) shows the results of X-ray diffraction (XRD) analysis of artificial graphite.

[0042] Figure 5 The results of experiments on the oxidation rates of anthracite and artificial graphite are shown.

[0043] Figure 6 is an Ellingham diagram showing the reactivity of each metal material with oxygen.

[0044] Figure 7 is a flow chart describing a method of manufacturing a compact by a method according to an embodiment of the present invention.

[0045] Figure 8 is a photograph of the microstructure of a compact produced by the method according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0046] Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention may be presented in different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that this disclosure will be comprehensive and complete, and will fully convey the scope of the present invention to those skilled in the art. The accompanying drawings may be exaggerated to describe embodiments of the present invention, and the same reference numerals in the accompanying drawings refer to the same elements.

[0047] Figure 1 is a diagram schematically showing an electric furnace provided with an electrode rod according to one embodiment of the present invention.

[0048] An electric furnace (electric melting furnace equipment) is an equipment for producing a melt (ie, liquid metal L) by dissolving raw materials M introduced into the interior thereof. Figure 1The electric furnace may include a main body 100 having an inner space capable of processing the raw material M, an electrode rod 200 installed so that a portion thereof is positioned inside the main body 100 to generate heat for melting the raw material M, and a power supply unit 300 connected to the electrode rod 200 to supply power. In addition, the electric furnace may include a raw material supply unit 400 installed to be connected to the main body 100 to introduce the raw material M.

[0049] The raw material M introduced into the internal space of the main body 100 may include a first raw material M1 and a second raw material M2. In addition, the first raw material M1 may include, for example, direct reduced iron (DRI). In addition, the second raw material M2 may include a reducing agent, and as a more specific example, the second raw material M2 may include coke. Inside the main body 100, the first raw material M1 and the second raw material M2 are dissolved by the heat generated by the electrode rod 200, and the first raw material M1 is reduced by the second raw material M2, thereby producing liquid metal L.

[0050] The direct reduced iron may be at least one of low-grade direct reduced iron produced using an ore having an iron (Fe) content of less than 65 wt% before reduction and high-grade direct reduced iron produced using an ore having an iron (Fe) content of more than 65 wt% before reduction. In addition, the direct reduced iron (DRI) as the first raw material M1 may be direct reduced iron reduced using hydrogen, i.e., "hydrogen direct reduced iron". Therefore, the electric furnace for producing liquid metal by melting and reducing the hydrogen direct reduced iron as the first raw material M1 may be referred to as an "electric furnace for melting hydrogen direct reduced iron".

[0051] In the above, it is described that the first raw material M1 introduced into the electric furnace includes hydrogen direct reduced iron. However, the first raw material M1 may include direct reduced iron manufactured by reduction in various ways in addition to direct reduced iron reduced by using hydrogen.

[0052] In addition, the first raw material M1 is not limited to direct reduced iron, and may include scrap having a higher iron (Fe) content than direct reduced iron. The scrap may be iron scrap having an iron (Fe) content greater than 70 wt %, more preferably, iron scrap having an iron (Fe) content of 85 wt % to 99 wt %.

[0053] The main body 100 may include a furnace body 110 having an inner space and a cover 120 for covering an opening provided at an upper side of the furnace body 110 .

[0054] The furnace body 110 may have a barrel shape having an inner space and an open upper side. The furnace body 110 may include an outer wall body 110a made of iron oxide scale or metal and an inner wall body 110b constructed of a refractory material to surround the inner wall of the outer wall body 110a.

[0055] The furnace body 110 may be provided with a first discharge port 111 for discharging the liquid metal L and a second discharge port 112 for discharging the slag S floating on the upper portion of the liquid metal L. The first discharge port 111 and the second discharge port 112 may each be provided on a side wall of the furnace body 110 or may be provided on a lower bottom portion of the furnace body 110. For example, referring to Figure 1 , the first discharge port 111 may be provided on one side wall of the furnace body 110, and the second discharge port 112 may be provided on the other side wall of the furnace body 110. Of course, the first discharge port 111 and the second discharge port 112 are not limited to the above positions, but may be provided at various positions capable of discharging the liquid metal L and the slag S to the outside.

[0056] Containers 10a and 10b capable of respectively containing liquid metal L and slag S are arranged outside the furnace body 110. That is, on the outer side of the furnace body 110, the first container 10a may be arranged at the lower side of the first discharge port 111, and the second container 10b may be arranged at the lower side of the second discharge port 112. Here, the first container 10a containing the liquid metal L discharged from the first discharge port 111 may be, for example, a ladle, and the second container 10b containing the slag S discharged from the second discharge port 112 may be a slag port.

[0057] The cover 120 is installed at the upper part of the furnace body 110 to close the upper opening of the furnace body 110. In this case, the cover 120 may be made of a refractory material. In addition, the cover 120 may be provided with a hole through which a portion of the electrode rod 200 passes and a hole through which a portion of the raw material supply unit 400 passes. In addition, the cover 120 may also be provided with an introduction port through which the raw material M may be introduced.

[0058] The raw material supply device 400 is a device for supplying the raw material M to the main body 100 of the electric furnace. The raw material supply unit 400 as described above may include, for example, a first hopper 410 storing a first raw material M1, a second hopper 420 storing a second raw material M2, and a supplier 430 connected to the first hopper 410 and the second hopper 420 to introduce the first raw material M1 and the second raw material M2 into the main body 100.

[0059] The supplier 430 may include, for example, a first transfer pipe 431 connected to the first hopper 410, a second transfer pipe 432 connected to the second hopper 420, and a third transfer pipe 433 having one end connected to the first transfer pipe 431 and the second transfer pipe 432 and the other end installed to pass through the cover 120 to be positioned in the internal space of the body 100. In addition, a valve may be installed on at least one of the first transfer pipe 431, the second transfer pipe 432, and the third transfer pipe 433.

[0060] In the above, it is described that the raw material supply device 400 includes the first hopper 410 and the second hopper 420. However, the present invention is not limited thereto, and a hopper in which raw materials other than the first raw material M1 and the second raw material M2 are stored may also be provided.

[0061] In addition, the raw material M is not limited to the raw material introduced using the raw material supply unit 400 as described above, and may also be introduced into the body 100 through an introduction port provided on the cover 120 .

[0062] Figure 2 is a sectional view showing a state in which an electrode rod according to one embodiment of the present invention is installed to be inserted into a main body of an electric furnace.

[0063] The electrode rod 200 generates heat and an arc using the supplied power, and supplies the heat into the body 100. Here, power may refer to voltage or current, and the heat generated by the electrode rod 200 may include resistance heat generated by the supplied power. Then, the heat and arc supplied into the body 100 by the electrode rod 200 melt or dissolve the raw material M, thereby manufacturing a melt, that is, liquid metal.

[0064] The electrode rod 200 may be provided in plural numbers, for example Figure 1 As described, three electrode rods 200 a , 200 b , and 200 c may be provided. In addition, the plurality of electrode rods 200 a , 200 b , and 200 c may be connected to one power supply unit 300 .

[0065] In the above, it is described that a plurality of electrode rods 200a, 200b, and 200c are connected to one power supply unit 300. However, the present invention is not limited thereto, and the power supply unit 300 may be provided in plural to be connected one-to-one to the plurality of electrode rods 200a, 200b, and 200c. In addition, the number of electrode rods is not limited to the above example, and the electrode rods may be set to one or three or more.

[0066] Hereinafter, the configuration of the electrode rod will be described. In this case, a plurality of electrode rods 200a, 200b, and 200c are provided with the same configuration and shape. Therefore, one electrode rod will be described as an example, and for ease of explanation, the reference numeral of the electrode rod is referred to as "200".

[0067] refer to Figure 2 The electrode rod 200 may include a housing 210 having an inner space, an electrode member 220 formed such that a portion thereof is inserted into the housing 210 to generate heat using electricity and the remaining portion protrudes to the outside of the housing 210, and a power supply member 230 mounted on the housing 210 to supply electricity to the housing 210. In addition, the electrode rod 200 may include a lifting device (not shown) connected to the housing 210 for lowering or lifting the housing 210.

[0068] like Figure 1 As shown, the electrode rod 200 is installed so that a part thereof is positioned inside the body 100, and the remaining part is positioned outside the body 100. That is, the electrode rod 200 may be installed to pass through the cover 120 in the vertical direction, thereby being partially positioned inside the furnace body 110. Therefore, a part of the electrode rod 200 is positioned at the lower side of the cover 120 to be accommodated inside the furnace body 110, and the other part thereof protrudes toward the upper side of the cover 120 to be positioned outside the furnace body 110. Then, the height of the electrode rod 200 is adjusted so that the lower part thereof is immersed in the slag S floating on the upper part of the liquid metal, or buried in the raw material M piled on the upper part of the slag S.

[0069] The housing 210 may have a barrel shape having an internal space. That is, the housing 210 may have a tubular shape having an internal space extending in a vertical direction and having an upper side and a lower side, both of which are open. The shape of the housing 210 is not particularly limited, but may be, for example, a cylindrical shape having a circular cross section. In addition, the housing 210 may be made of metal.

[0070] As described above, the electrode rod 200 is installed so that a portion thereof is positioned inside the furnace body 110 and the remaining portion thereof is positioned outside the furnace body 110. To this end, the housing 210 is installed so that a portion thereof is positioned inside the furnace body 110 and the remaining portion thereof is positioned outside the furnace body 110 by vertically penetrating the cover 120.

[0071] The power supply member 230 is a device that delivers the power received from the power supply unit 300 to the housing 210. Figure 2As shown, the power supply member 230 may be installed in the housing 210 to be positioned outside the body 100, i.e., on the upper side of the cover 120. The material of the power supply member 230 is not particularly limited as long as it is a conductor capable of transmitting power, but may be made of a material including copper (Cu), for example.

[0072] In addition, the power supply line 310 may be connected between the power supply unit 300 and the power supply member 230. Therefore, the power output from the power supply unit 300 may be delivered to the power supply member 230 via the power supply line 310. In addition, the power delivered to the power supply member 230 may be delivered to the housing 210 and then delivered to the electrode member 220 inside the housing 210.

[0073] like Figure 2 As shown, the electrode member 220 is connected to the housing 210 so that a portion thereof protrudes to the outside of the lower side of the housing 210. That is, the electrode member 220 is connected so that a portion thereof is positioned inside the housing 210 and the remaining portion protrudes outside the housing 210. The above-mentioned electrode member 220 is made of a material containing carbon (C), and generates resistance heat when power is supplied thereto. In addition, at this time, an arc can be generated around the electrode member 220.

[0074] The electrode member 220 is a self-baking electrode manufactured by firing a material introduced into the housing 210. Hereinafter, for convenience of explanation, the material introduced into the housing of the electrode rod 200 to manufacture or form the electrode member 220 is referred to as an "electrode rod composition".

[0075] The electrode member 220 is not connected to the case 210 after being manufactured into a predetermined shape (eg, a rod-like shape), but is prepared by introducing a composition for an electrode rod into the case 210 and firing the introduced composition for an electrode rod by heating.

[0076] Meanwhile, if the power delivered to the housing 210 is delivered to the electrode member 220, heat is generated in the electrode member 220, and an arc is generated around the electrode member 220. Therefore, the first raw material M1 and the second raw material M2 inside the main body 100 are melted, thereby manufacturing the liquid metal L. At this time, the electrode member 220 is oxidized by the air introduced into the main body 100 and by the oxidized metal generated inside the main body 100, and due to the oxidation reaction, at least one of the length and the diameter of the electrode member 220 is reduced. That is, the electrode member 220 is consumed. In addition, the electrode member 220 may also be consumed by the arc generated around the electrode member 220. As described above, the electrode member 220 is a consumable electrode in which at least one of its length and diameter is reduced due to the oxidation reaction and the arc.

[0077] Therefore, in order to continuously or sequentially form the electrode member 220 while the electric furnace is operating, the electrode rod composition for forming the electrode member 220 is introduced into the housing 210. The introduced electrode rod composition becomes the electrode member 220 in a solid phase through softening, melting and firing reactions inside the housing 210.

[0078] The electrode rod composition may include a material containing carbon (C) and a binder, and the material containing carbon may be in the form of small-sized particles or powder. Therefore, the material containing carbon (C) and the binder are mixed and formed to produce a compact (or elliptical compact) B, and the produced compact B is introduced into the housing 210.

[0079] When the compact B is introduced into the housing 210, the compact B is fired, and thus, the electrode member 220 is manufactured. That is, when power is supplied to the housing 210 through the power supply unit 300 and the power supply member 230, the power is transmitted to the compact B introduced into the housing 210. Therefore, resistance heat is generated in the compact B, and thus, the compact is softened. Then, the compact softened by the resistance heat generated by the continuous supply of power is dissolved or melted, and thereafter, undergoes a firing reaction to be manufactured as the electrode member 220 in a solid state.

[0080] The area of ​​the housing 210 inside the main body 100 has a high temperature, and therefore, may melt and disappear over time. That is, the lower portion of the housing 210 adjacent to the bottom of the main body 100 of the housing 210 inserted in the main body 100 melts and disappears. Therefore, when the electric furnace is operated, the housing 210 decreases over time.

[0081] In addition, as described above, the electrode member 220 protruding to the lower side of the housing 210 is consumed. Therefore, while the housing 210 is reduced over time, the compact B manufactured by assembling the composition for the electrode rod is introduced into the housing 210. Therefore, the electrode member 220 can be continuously formed while the electric furnace is operating, and the electrode member 220 can protrude to the lower side of the housing 210.

[0082] Furthermore, for this purpose, the briquettes B are continuously introduced into the housing 210 as described above, so that the inner space of the housing 210 can be divided from the upper side to the lower side into briquettes zones Z into which the briquettes B are introduced. br Softening zone Z s , Melting Zone Z m and firing zone Z ba That is, the upper space of the electrode member 220 inside the housing 210 may be divided into a block zone Z in which the introduced block B maintains a solid phase state. br , the softening zone Z in which the block is softened by heat s , a melting zone Z in which the softened compact is melted m, and a firing zone Z in which the molten compact is fired ba In other words, the interior space of the housing 210 can be described as including the block zone Z br Softening zone Z s , Melting Zone Z m and firing zone Z ba In this case, since the electrode member 220 is provided after the compact B is softened, melted, and fired, it can be described as the electrode member 220 being connected to the firing zone Z. ba The lower part.

[0083] Figure 3 (a) is a photograph of the electrode member of the electrode rod before being pencil-shaped, and Figure 3 (b) is a photograph of the electrode structure after being pencil-shaped.

[0084] As described above, the electrode member 220 contains carbon (C). In addition, carbon (C) is easily oxidized by oxygen (O). Therefore, the electrode member 220 may have a relative humidity with the air introduced into the main body 100 of the electric furnace and the oxidizing gas (e.g., CO) generated inside the main body 100. 2 (carbon dioxide)) and the like. In addition, when power is supplied and heat is generated in the electrode member 220, an arc may be generated together. Therefore, the electrode member 220 may be consumed due to the oxidation reaction and the arc. That is, penciling in which the diameter of the electrode member 220 is reduced may occur. Reference Figure 3 (a) and (b), due to the oxidation reaction and the arc, the diameter D of the electrode member 220 after penciling 2 smaller than the diameter D of the electrode member 220 before penciling occurs 1 (D 1 >D 2 ). In this case, the consumption of the electrode member 220 due to the oxidation reaction is greater than the consumption of the electrode member 220 due to the arc.

[0085] In the case of pencil-like formation in which the diameter of the electrode member 220 is reduced, the area of ​​the region where heat is generated in the electrode member 220 may be reduced, and the region where the arc is generated around the electrode member 220 may be reduced. Therefore, when the liquid metal L is manufactured by melting the raw material M with the heat and arc generated by the electrode member 220, the operation efficiency may be reduced.

[0086] Therefore, it is necessary to improve the oxidation resistance of the electrode member 220 so that the oxidation reaction is suppressed or prevented. In other words, it is necessary to manufacture an electrode member 220 with improved oxidation resistance. To this end, in an embodiment, the electrode member 220 is manufactured by using a first carbon-based material containing artificial graphite. That is, the electrode rod composition for manufacturing the electrode member 220 contains a first carbon-based material, and the first carbon-based material contains artificial graphite. In addition, the electrode rod composition contains an antioxidant material and a binder, and the antioxidant material contains a material having better oxidation characteristics than carbon (C). In addition, the electrode rod composition may also contain a second carbon-based material different from the first carbon-based material.

[0087] In summary, as shown in Table 1, the composition for an electrode rod may include a first carbon-based material including artificial graphite, an antioxidant material including a material having better oxidation characteristics than carbon (C), and a binder (first embodiment). In this case, the first carbon-based material may be included at 50 wt % to 65 wt %, the antioxidant material may be included at 1 wt % to 7 wt %, and the binder may be included at 30 wt % to 43 wt %.

[0088] [Table 1]

[0089]

[0090] In addition, more preferably, the electrode rod composition may further include a second carbon-based material containing at least one of natural graphite and coke (second embodiment and third embodiment). That is, the electrode rod composition according to the second embodiment may include natural graphite, and the electrode rod composition according to the third embodiment may include coke. Here, natural graphite used as the second carbon-based material is used to improve the conductivity of the electrode member 220, and coke is used to improve the strength of the electrode member 220.

[0091] In this case, the first carbon-based material may be included at 50 wt % to 60 wt %, the antioxidant material may be included at 1 wt % to 5 wt %, the second carbon-based material may be included at 1 wt % to 5 wt %, and the binder may be included at 30 wt % to 40 wt %.

[0092] In addition, the second carbon-based material of the composition for an electrode rod may contain both natural graphite and coke (fourth embodiment). In this case, the content of each of natural graphite and coke is 1 wt % to 5 wt %, and the total content of natural graphite and coke is adjusted to a range of 1 wt % to 5 wt %.

[0093] As described above, in the composition for electrode rods according to the embodiment, the first carbon-based material is mixed at a maximum content of 50 wt % to 65 wt % or 50 wt % to 60 wt %. Therefore, it can be described that the first carbon-based material is the main material among the materials contained in the composition for electrode rods.

[0094] Meanwhile, a typical composition for an electrode rod uses anthracite as a carbon-based material. That is, a typical composition for an electrode rod contains anthracite and a binder, wherein the anthracite is contained at 60 to 70 weight %, and the binder is contained at 30 to 70 weight %. However, anthracite is low in crystallinity, has a large number of cracks and pores, and is thus rapidly oxidized.

[0095] On the other hand, graphite has a hexagonal crystal structure and has high crystallinity. More specifically, graphite has a hexagonal platelet crystal structure. In addition, artificial graphite has stronger mechanical strength than natural graphite.

[0096] Therefore, in the embodiment, graphite is used as the carbon-based material. More specifically, artificial graphite is used as the first carbon-based material, which is the main material. In other words, anthracite, which is generally used as the main carbon-based material, is not used, and artificial graphite is used as an alternative material to anthracite.

[0097] Figure 4 (a) shows the results of X-ray diffraction (XRD) analysis of anthracite, and Figure 4 (b) shows the results of X-ray diffraction (XRD) analysis of artificial graphite.

[0098] In the following, reference is made to Figure 4 , the crystallinity of anthracite and artificial graphite will be described.

[0099] For XRD analysis, samples made of anthracite and samples made of artificial graphite were prepared separately. Then, XRD analysis was performed on each sample, and the results were as follows: Figure 4 shown.

[0100] In the XRD analysis results, the higher the intensity of the highest peak with the maximum intensity, and the smaller the half width of the highest peak, the higher the crystallinity. Figure 4 Comparing the highest peak intensity of (a) and (b), the highest peak intensity of artificial graphite ( Figure 4 (b)) is higher than the highest peak intensity of anthracite ( Figure 4(a)). More specifically, in the case of anthracite, the intensity of the highest peak is as low as 1,300 counts per second (cps), whereas in the case of artificial graphite, the intensity of the highest peak is about 220,000 cps, which is 160 times higher than that of the highest peak of anthracite. In addition, comparing the half widths of the highest peaks, the half width of the highest peak of artificial graphite is narrower than that of the highest peak of anthracite.

[0101] In addition, the crystal thickness and crystal length can be obtained from Figure 4 The XRD results shown in (a) and (b) are calculated. In the case of anthracite, Figure 4 The crystal thickness calculated from the result of (a) is to And the crystal length is to On the other hand, in the case of artificial graphite, Figure 4 The crystal thickness calculated from the result of (b) is to And the crystal length is to That is, the crystal thickness and crystal length of artificial graphite are greater than those of anthracite. From the above, it can be seen that the crystallinity of artificial graphite is higher than that of anthracite.

[0102] As mentioned above, the crystallinity of artificial graphite is higher than that of anthracite. In addition, the higher the crystallinity, the more stable it is, and therefore, the lower the reactivity with other components. From this, it can be seen that the oxidation reaction activity of artificial graphite is lower than that of anthracite.

[0103] In addition, natural graphite has a hexagonal flake crystal structure similar to artificial graphite. Therefore, natural graphite has a higher crystallinity than anthracite. In addition, natural graphite has a lower mechanical strength than artificial graphite.

[0104] Figure 5 The results of experiments on the oxidation rates of anthracite and artificial graphite are shown.

[0105] In the following, reference is made to Figure 5 , describing the oxidation rates of anthracite and artificial graphite. In order to determine the oxidation rates of anthracite and artificial graphite, a thermogravimetric analysis experiment was conducted. To this end, the following experiment was conducted. First, a first sample made of anthracite and a second sample made of artificial graphite were prepared. Then, the first sample and the second sample were introduced into a furnace whose temperature was adjusted to 700°C, and air was supplied to the furnace. Thereafter, the weight (weight) of each of the first sample and the second sample was measured over time, and the rate of change of weight was calculated, and the results are shown in Figure 5 Here, the weight change rate can be the weight W of the sample after it is introduced into the electric furnace. 2Relative to the W of the sample before it was introduced into the electric furnace 1 ratio (see Equation 1).

[0106] [Equation 1]

[0107] Weight reduction rate (%) = (W 2 / W 1 )×100%

[0108] Reference Figure 5 , the rate of weight reduction of the second sample (artificial graphite) is slower than the rate of weight reduction of the first sample (anthracite). From the above, it can be seen that when artificial graphite is used as a component for the electrode rod, the rate at which the electrode member 220 is oxidized can be slowed down compared to when anthracite is used. That is, it can be seen that when artificial graphite is used, the oxidation resistance of the electrode member 220 can be improved compared to when anthracite is used as a component for the electrode rod.

[0109] Figure 6 is an Ellingham diagram showing the reactivity of each metal material with oxygen.

[0110] As the antioxidant material, a material having better reactivity with oxygen (O) than carbon (C) is used. In other words, a material capable of delaying the oxidation reaction of carbon by first reacting with oxygen before the oxidation reaction caused by the reaction between carbon (C) and oxygen (O) is used as the antioxidant material.

[0111] See also Figure 6 , materials having a higher reactivity (i.e., oxygen affinity) with oxygen than carbon (C) include Zn, Cr, Mn, Si, Ti, Al, Mg, and Ca. Among the above, it is preferred to use at least one of Al and Si as an antioxidant material. This is because in the case of liquid metal L manufactured in an electric furnace, it is necessary to adjust the content of at least one of Al and Si to a predetermined amount or more. In addition, Al and Si used as antioxidant materials may be metals. That is, Al and Si may be in a metallic state, rather than oxides, carbides, or nitrides. In other words, Al and Si may be metal Al and metal Si having a purity of 95% or more, more preferably 99% or more.

[0112] As described above, in the embodiment, a material having a better oxygen affinity (i.e., better oxidation reactivity) than carbon (C) is used as an antioxidant material. Therefore, at least one of the antioxidant material, such as Al and Si, reacts with oxygen first before the carbon (C) contained in the electrode member 220. Therefore, the oxidation reaction of the carbon (C) contained in the electrode member 220 can be delayed. Here, the carbon (C) contained in the electrode member 220 can be contained in artificial graphite as a first carbon-based material and natural graphite as a second carbon-based material. In addition, in the electrode rod composition for manufacturing the electrode member 220, the first carbon-based material is contained in a large amount of 50% to 65% by weight or 50% to 60% by weight, and the second carbon-based material containing natural graphite is contained in an amount of 1% to 5% by weight. In addition, the amount of the combination of the first carbon-based material and the second carbon-based material is 51% to 65% by weight. Therefore, compared with other components, the electrode member 220 contains a large amount of carbon (C).

[0113] Therefore, when the oxidation reaction of carbon (C) among the components included in the electrode member 220 is suppressed or delayed, oxidation of the electrode member 220 may be effectively suppressed.

[0114] Figure 7 is a flow chart describing a method of manufacturing a compact by a method according to an embodiment of the present invention. Figure 8 is a photograph of the microstructure of a compact produced by the method according to the first embodiment of the present invention.

[0115] In order to manufacture the compact B, firstly, a composition for an electrode rod is prepared S10. That is, a first carbon-based material containing artificial graphite is prepared S11, an antioxidant material is prepared S12, and a binder is prepared S14. Then, the first carbon-based material, the antioxidant material, and the binder are mixed S15. Thus, a composition for an electrode rod is prepared S10. That is, a composition for an electrode rod according to the first embodiment is prepared. In this case, each of the first carbon-based material, the antioxidant material, and the second carbon-based material may be in a solid phase state including a solid powder or a plurality of particles.

[0116] In addition, the composition for electrode rods may further include a second carbon-based material S13 containing at least one of natural graphite and coke. Therefore, in addition to the first carbon-based material, the antioxidant material and the binder, the second carbon-based material S13 may be included to prepare the composition for electrode rods (second and third embodiments).

[0117] Artificial graphite can be produced by adding a binder to pitch coke or petroleum coke and then heat-treating the mixture at a high temperature to graphitize it. In other words, artificial graphite can be obtained by treating pitch coke or petroleum coke.

[0118] In addition, the artificial graphite used as the first carbon-based material can be newly processed and prepared in the same manner as described above, or can be recovered from discarded artificial graphite (waste artificial graphite). Here, the waste artificial graphite can be recovered from the electrode for electric discharge machining or the crucible and heater of the silicon wafer (Si wafer) growth device. First, with respect to the electrode for electric discharge machining, when the mold is manufactured, electric discharge machining is performed, and at this time, the electrode made of artificial graphite is used as the electrode for electric discharge machining. In addition, the crucible and heater provided in the silicon wafer growth device are manufactured using artificial graphite. Therefore, artificial graphite is recovered from at least one of the discarded electrode, crucible and heater for electric discharge machining and used as the first carbon-based material. As another example, artificial graphite that is waste material generated during the manufacture of at least one of the electrode, crucible and heater for electric discharge machining can be recovered and used as the first carbon-based material. As described above, since artificial graphite as waste material is recovered as the first carbon-based material, the cost for manufacturing an electrode rod or an electrode member can be reduced.

[0119] The antioxidant material may be at least one of Al and Si. In addition, the binder may include coal tar pitch, and may further include a phenolic resin.

[0120] When the first carbon-based material, the antioxidant material, and the binder are mixed S15 to prepare the composition for an electrode rod according to the first embodiment, the mixing is performed so that the first carbon-based material is contained at 50 wt % to 65 wt %, the antioxidant material is contained at 1 wt % to 7 wt %, and the binder is contained at 30 wt % to 43 wt % (see Table 1).

[0121] In addition, when a second carbon-based material is further mixed S15 in addition to the first carbon-based material, the antioxidant material, and the binder to prepare the composition for an electrode rod according to the second and third embodiments, the mixing is performed so that the first carbon-based material is contained at 50 wt % to 65 wt %, the antioxidant material is contained at 1 wt % to 5 wt %, the binder is contained at 30 wt % to 40 wt %, and the second carbon-based material is contained at 1 wt % to 5 wt % (see Table 1).

[0122] In the case of the second embodiment, a material containing natural graphite is used as the second carbon-based material, and in the case of the third embodiment, a material containing coke is used as the second carbon-based material. In addition, in the case of the second embodiment, coal tar pitch may be used as a binder, and in the case of the third embodiment, a mixture of coal tar pitch and phenolic resin may be used as a binder. In this case, in the binder according to the third embodiment, coal tar pitch may be contained at 60 wt % to 70 wt %, and phenolic resin may be contained at 30 wt % to 40 wt % in the entire binder.

[0123] Meanwhile, in the electrode rod composition, if the content of the first carbon-based material is less than 50 wt %, the resistance of the electrode member 220 may be high or its strength may be weak. On the contrary, if the content of the first carbon-based material in the electrode rod composition is greater than 65 wt %, as the content of at least one of the antioxidant material, the second carbon-based material and the binder decreases, the effect of reducing the oxidation rate of the electrode member 220 may not be significant, its resistance may be high, or its strength may be weak.

[0124] If the content of the antioxidant material is less than 1 wt%, the effect of reducing the oxidation rate of the electrode member 220 may not be significant. In addition, in the range where the content of the antioxidant material is greater than 7 wt%, the effect of delaying the oxidation reaction of carbon (C) contained in the electrode member 220 may not be significant. In addition, in order to manufacture a liquid metal having a desired component content, the content of the antioxidant material in the composition for the electrode rod should be 7 wt% or less. Therefore, mixing is performed so that the antioxidant material is contained in an amount of 1 wt% to 7 wt%.

[0125] If the binder is contained at less than 30 wt %, the strength of the compact may be weak. On the contrary, if the content of the binder is greater than 43 wt %, the content of other materials is relatively reduced, so that the resistance of the electrode member may increase, its oxidation rate may increase, or its strength may decrease.

[0126] Therefore, the composition for an electrode rod is prepared by mixing so as to contain 50 to 65 wt % of the first carbon-based material, 1 to 7 wt % of the antioxidant material, and 30 to 43 wt % of the binder therein.

[0127] In addition, the composition for the electrode rod may further include a second carbon-based material, and at this time, the second carbon-based material is mixed to be included in 1 wt% to 5 wt%, and the second carbon-based material may include at least one of natural graphite and coke. At this time, in order to further improve the conductivity of the electrode member 220, the second carbon-based material including natural graphite is used, and in order to improve the strength of the electrode member 220, the second carbon-based material including coke is used.

[0128] When the second carbon-based material containing natural graphite is used, for example, if the second carbon-based material is contained at less than 1 wt%, the effect of improving the conductivity of the electrode member 220 may not be significant. In addition, when the second carbon-based material containing coke is used, for example, if the second carbon-based material is contained at less than 1 wt%, the effect of improving the strength of the electrode member 220 may not be significant. In addition, if the content of the second carbon-based material containing at least one of natural graphite and coke is greater than 7 wt%, the second carbon-based material may not be smoothly mixed with other materials. That is, in the composition for an electrode rod in which the first carbon-based material, the antioxidant material, the binder, and the second carbon-based material are mixed, there may be a case in which the second carbon-based material is not mixed to be uniformly distributed and agglomerated on either side.

[0129] Therefore, mixing is performed so as to contain 50 wt % to 60 wt % of the first carbon-based material, 1 wt % to 5 wt % of the antioxidant material, 30 wt % to 40 wt % of the binder, and 1 wt % to 5 wt % of the second carbon-based material.

[0130] When the composition for an electrode rod is prepared, the composition is loaded into a molding machine and assembled S20. Thus, a compact B having a predetermined size is manufactured.

[0131] In the above, it has been described that each of the first carbon-based material, the antioxidant material, and the second carbon-based material is prepared in a solid particle or powder state. However, the present invention is not limited thereto, and the antioxidant material may be provided in a liquid phase. In addition, the liquid antioxidant material may be coated on the surface of the particles of the first carbon-based material, and then the first carbon-based material coated with the antioxidant material may be mixed with the second carbon-based material and a binder.

[0132] The compact B manufactured by the above method comprises a first carbon-based material, an antioxidant material and a binder. In addition, a second carbon-based material may also be included. Figure 8When observing the microstructure of a green block manufactured using the composition for an electrode rod according to the second embodiment in which a second carbon-based material containing natural coke is mixed, it can be determined that artificial graphite as the first carbon-based material, an antioxidant material, and natural graphite as the second carbon-based material are contained.

[0133] When manufacturing the compact B, the compact B is introduced into the housing 210 of the electrode rod 200 installed in the main body 100 of the electric furnace. Figure 2 As shown, the compact B is introduced into the opening on the upper side of the housing 210 .

[0134] The block B introduced into the housing 210 sequentially undergoes a softening process, a melting process, and a firing process by power supplied to the housing 210 via the power supply member 230 and heat inside the body 100, and as a result, forms the electrode member 220. In this case, a portion of the electrode member 220 may be formed by extending to protrude to the outside of the lower side of the housing 210.

[0135] The first and second raw materials M1 and M2 charged into the body 100 are melted or dissolved by heat generated by the electrode member 220 and arcs generated around the electrode member 220, and as a result, liquid metal L is produced. Then, the produced liquid metal L is discharged through the first discharge port 111 and then charged into the first container 10a.

[0136] Table 2 shows the characteristics of the electrodes manufactured by the methods according to the first to third experimental examples. The first experimental example is an electrode manufactured using a composition for an electrode rod containing anthracite and a binder. In addition, the second experimental example is an electrode manufactured using a composition for an electrode rod according to the second embodiment of the present invention, and the third experimental example is an electrode manufactured using a composition for an electrode rod according to the third embodiment of the present invention.

[0137] For the experiment, the composition for electrode rod according to each of the first to third experimental examples was prepared and assembled to prepare a compact. Then, the compact according to each of the first to third experimental examples was heat treated and fired to manufacture an electrode member. In this case, the compact according to each of the first to third experimental examples was heated at the same temperature and for the same time.

[0138] Then, for the electrode member according to each of the first to third experimental examples, the density (g / cm 3 ), resistivity (μΩm) and bending strength (MPa). Here, the bending strength was measured by a three-point bending strength measurement method.

[0139] Furthermore, the oxidation rate was represented by an index and was represented by a ratio of the oxidation rate of the electrode members according to the second and third experimental examples to the oxidation rate of the electrode member according to the first experimental example.

[0140] In addition, each electrode member according to the first to third experimental examples as described above was prepared in plural, and the density, resistivity and bending strength of each of the plural electrode members were measured, and the oxidation rate was calculated as an index, and the results are shown in Table 2.

[0141] [Table 2]

[0142]

[0143] Referring to Table 2, the first to third experimental examples have similar density levels. However, the oxidation rates of the second and third experimental examples are slower than that of the first experimental example. That is, the oxidation rate index of the first experimental example is 1, while the oxidation rate index of the second experimental example is 0.5 to 0.6, and the oxidation rate index of the third experimental example is greater than 0.6 to 0.7. It can be seen from the above results that if the composition for electrode rods according to the embodiment is used, the oxidation rate of the electrode member can be slowed down. That is, it can be seen that the oxidation resistance of the electrode member can be improved.

[0144] Therefore, the oxidation rate of the electrode member according to each of the second and third experimental examples is slower than that of the first experimental example because artificial graphite having better crystallinity than anthracite is used as the first carbon-based material. In addition, the oxidation reaction of carbon (C) is delayed because a material having better oxidation reactivity than carbon (C) is used as an antioxidant material.

[0145] Comparing the resistivity, the resistivity of each of the second and third experimental examples is lower than that of the first experimental example. That is, the conductivity of each of the second and third experimental examples is higher than that of the first experimental example. If the conductivity of the electrode member is high due to the small resistivity, an arc can be generated around the electrode member, and the arc can be generated in a uniform distribution. Therefore, when the raw material is dissolved by the heat of the arc to generate liquid metal, liquid metal can be generated in a uniform amount around the electrode rod.

[0146] In addition, comparing the second experimental example and the third experimental example, the resistivity of the second experimental example using natural graphite as the second carbon-based material is lower than that of the third experimental example. In addition, the bending strength of the third experimental example using coke as the second carbon-based material is higher than that of the second experimental example. From the above results, it can be seen that if natural graphite is used as the second carbon-based material, the resistivity of the electrode member can be further reduced, and if coke is used, the strength of the electrode member can be further improved.

[0147] As described above, according to the embodiment of the present invention, the oxidation resistance of the electrode member set in the electrode rod of the electric furnace can be improved, and thus, the rate at which the electrode member is oxidized can be reduced. Therefore, pencil-like reduction in the diameter of the electrode member due to oxidation reaction can be suppressed.

[0148] In addition, the reduction in the area of ​​the region where heat is generated in the electrode member due to penciling and the decrease in the temperature of the region, or the reduction in the region where arcs are generated around the electrode member, can be suppressed. Therefore, when liquid metal is produced by melting raw materials with heat and arcs generated by the electrode member, the operating efficiency can be improved.

[0149] In addition, since the oxidation resistance of the electrode member is improved, the life of the electrode member can be improved. Therefore, during the operation of the electric furnace, the amount of the electrode rod composition introduced into the housing to form the electrode member can be reduced, and the introduction period can be extended. Therefore, due to the introduction of the electrode rod composition, there is an effect of reducing costs.

[0150] In addition, the resistivity of the electrode member can be reduced. Therefore, the efficiency of generating heat and arc by the power supplied in the electrode rod can be improved.

[0151] Industrial Applicability

[0152] According to the embodiment of the present invention, the oxidation resistance of the electrode member provided in the electrode rod of the electric furnace can be improved, and thus, the rate at which the electrode member is oxidized can be reduced. Therefore, pencil-like reduction in the diameter of the electrode member due to oxidation reaction can be suppressed.

Claims

1. A composition for an electrode rod for manufacturing an electrode member of an electric furnace, the composition comprising a first carbon-based material, an antioxidant material, and a binder, the first carbon-based material comprising artificial graphite, the antioxidant material comprising a material having a higher reactivity with oxygen (O) than carbon (C).

2. The composition for an electrode rod according to claim 1, wherein in the entire composition for an electrode rod, the content of the first carbon-based material is 50 wt% to 65 wt%, the content of the antioxidant material is 1 wt% to 7 wt%, and the content of the binder is 30 wt% to 43 wt%. 3 . The composition for an electrode rod according to claim 1 , further comprising a second carbon-based material containing at least one of natural graphite and coke.

4. The composition for an electrode rod according to claim 3, wherein in the entire composition for an electrode rod, the content of the first carbon-based material is 50 wt% to 60 wt%, the content of the antioxidant material is 1 wt% to 5 wt%, and the content of the binder is 30 wt% to 40 wt%, and the content of the second carbon-based material is 1 wt% to 5 wt%. 5 . The composition for an electrode rod according to claim 2 , wherein a scrap containing artificial graphite is used as the first carbon-based material. 6 . The composition for an electrode rod according to claim 2 , wherein the antioxidant material comprises at least one of metal Al and metal Si.

7. The composition for an electrode rod according to claim 2 or claim 4, wherein the first carbon-based material and the second carbon-based material are provided in a solid state including a plurality of particles, the antioxidant material is provided in a liquid state, and the antioxidant material is coated on the surfaces of the particles of the first carbon-based material.

8. An electrode rod installed so that a portion of the electrode rod is inserted into a main body of an electric furnace, the electrode rod comprising: a housing having an inner space formed by extending in one direction; and An electrode member, the electrode member is formed by inserting a green block into the shell and firing the green block, and is formed so that a part of the electrode member is positioned inside the shell and the remaining part protrudes to the outside of the lower side of the shell, the green block contains a first carbon-based material, an antioxidant material and a binder, the first carbon-based material contains artificial graphite, and the antioxidant material contains a material having a higher reactivity with oxygen (O) than carbon (C). 9 . The electrode rod according to claim 8 , wherein the antioxidant material comprises at least one of metal Al and metal Si. 10 . The electrode rod of claim 8 , wherein the briquette comprises a second carbon-based material including at least one of natural graphite and coke.

11. A method for manufacturing an electrode rod, the method comprising: manufacturing a compact comprising a first carbon-based material comprising artificial graphite, an antioxidant material having a higher reactivity with oxygen (O) than carbon (C), and a binder; inserting the compact into a housing of an electrode rod mounted to be inserted into a body of an electric furnace; as well as An electrode member is formed by firing the compact using heat inside the body and electricity supplied to the case.

12. The method of claim 11, wherein said manufacturing the compact comprises: preparing a composition for an electrode rod by mixing the first carbon-based material, the antioxidant material, and the binder; as well as The electrode rod is assembled with the composition.

13. The method of claim 11, wherein said manufacturing a compact comprises: coating the antioxidant material on surfaces of particles of the first carbon-based material; preparing a composition for an electrode rod by mixing the first carbon-based material coated with the antioxidant material and the binder; as well as The electrode rod is assembled with the composition.

14. The method according to claim 12, wherein the preparation of the composition for electrode rod comprises: preparing a second carbon-based material comprising at least one of natural graphite and coke; as well as The first carbon-based material, the antioxidant material, the binder, and the second carbon-based material are mixed.

15. The method according to claim 13, wherein the preparation of the composition for electrode rod comprises: preparing a second carbon-based material comprising at least one of natural graphite and coke; as well as The first carbon-based material coated with the antioxidant material, the binder, and the second carbon-based material are mixed.

16. A method for producing liquid metal, the method comprising: Inserting the raw material into the body of the electric furnace; inserting a compact into a housing of an electrode rod installed so that a portion thereof is positioned inside the body, the compact comprising a first carbon-based material comprising artificial graphite, an antioxidant material having a higher reactivity with oxygen (O) than carbon (C), and a binder; forming an electrode member by firing the green block inside the case, wherein a portion of the electrode member is positioned inside the case and a remaining portion protrudes outside a lower side of the case; as well as The raw material is melted by supplying power to the electrode rods to generate heat. 17 . The method of claim 16 , further comprising first reacting the antioxidant material contained in the electrode member with oxygen (O) instead of reacting carbon (C) contained in the electrode member with oxygen (O). 18 . The method of claim 17 , wherein reacting the antioxidant material with oxygen (O) comprises reacting at least one of Al and Si contained in the antioxidant material with oxygen (O).

19. The method of claim 16, wherein the briquette comprises a second carbon-based material comprising at least one of natural graphite and coke.

20. A method according to any one of claims 16 to 19, wherein the raw material comprises hydrogen direct reduced iron reduced by hydrogen.

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