Operating method of copper smelting furnace and granules

Abstract

The present invention provides a method for operating a copper smelting furnace that can efficiently react a sulfur source with metallic components in the matte phase while reducing losses due to the volatilization of the sulfur source, and also provides a granulated material. [Solution] The copper smelting operation method involves, when processing recycled raw materials in a copper smelting furnace, mixing a sulfur-containing substance with the recycled raw materials at a predetermined mixing ratio and pressurizing it to obtain granules which are then introduced into the copper smelting furnace, wherein the recycled raw materials include metallic metals that sulfide to form a mat, and a lower limit is set on the specific surface area of ​​the metallic metals used in the granules.

Description

[Technical Field]

[0001] This invention relates to a method for operating a copper smelting furnace and to granulated materials. [Background technology]

[0002] In a copper smelting furnace, copper concentrate, solvents, and other smelting materials are introduced from the concentrate burner along with reaction gases. The smelting materials undergo an oxidation reaction due to the reaction gases, producing matte and slag. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2007-092133 [Patent Document 2] Special Publication No. 51-047410 [Overview of the project] [Problems that the invention aims to solve]

[0004] In recent years, the proportion of recycled materials used in smelting has been increasing. However, recycled materials contain metallic elements such as Cu, Fe, Sn, Zn, Pb, and Al, which are largely present as pure metals or alloys without oxidation or sulfidation. In this invention, these are defined as metallic components. Therefore, when increasing the processing volume of recycled materials in a copper smelting furnace, a sulfur source is required to mattify the metallic components. When this sulfur source is introduced into the copper smelting furnace, measures are needed to react the sulfur source with the metallic components in the matt phase.

[0005] The present invention has been made in view of the above problems, and in particular aims to provide a method for operating a copper smelting furnace that can efficiently react a sulfur source with metallic components in the matte phase while reducing losses due to the volatilization of the sulfur source, and a granulated product. [Means for solving the problem]

[0006] The copper smelting operation method according to the present invention is a method of processing recycled raw materials in a copper smelting furnace, in which granules obtained by mixing a sulfur-containing material with the recycled raw materials at a predetermined mixing ratio and pressurizing them are introduced into the copper smelting furnace, wherein the recycled raw materials include a metallic metal that sulfides to form a mat, and a lower limit is set for the specific surface area of ​​the metallic metal used in the granules. The lower limit for the specific surface area is 1.2 mm. 2 / mm 3 The above may also be used. The recycled material may be sieved with a sieve of 5 mm or less, and the sieved portion may be mixed with the sulfur-containing material and pressurized. The sulfur-containing material may be copper concentrate. The recycled material may be a metal. The metal may be copper. The copper smelting furnace may be a self-smelting furnace.

[0007] Another copper smelting operation method according to the present invention is a method of processing recycled raw materials in a copper smelting furnace, in which granules obtained by mixing a sulfur-containing material with the recycled raw materials in a predetermined mixing ratio and pressurizing them are introduced into the copper smelting furnace, wherein the recycled raw materials include a metallic metal that sulfides to form a mat, and the specific surface area of ​​the metallic metal used in the granules is 1.2 mm². 2 / mm 3 The above is correct. The recycled material may be sieved with a sieve of 5 mm or less, and the sieved portion may be mixed with the sulfur-containing material and pressurized.

[0008] The granules according to the present invention contain sulfur-containing material with a specific surface area of ​​1.2 mm². 2 / mm 3 This material is obtained by mixing recycled raw materials containing the above metallic metals in a predetermined mixing ratio and then applying pressure. The granulated material has an apparent density (g / cm³). 3 ) may be 3.5 or higher. The sulfur-containing substance may be copper concentrate. [Effects of the Invention]

[0009] According to the present invention, there are provided an operating method for a copper smelting furnace and a granulated product that can efficiently react a sulfur source with metallic components in a matte phase while reducing losses due to volatilization of the sulfur source.

Brief Description of the Drawings

[0010] [Figure 1] It is a diagram schematically showing the configuration of an autogenous furnace for copper smelting according to an embodiment. [Figure 2] It is a diagram illustrating details of the concentrate burner. [Figure 3] It is a phase diagram showing the solubility of Cu in matte. [Figure 4] It is a diagram illustrating the fall of the granulated product. [Figure 5] It is a diagram illustrating a pelletizer. [Figure 6] It is a diagram illustrating the fall of the granulated product. [Figure 7] It is a diagram for explaining an example. [Figure 8] It is a diagram showing the weight of the sediment derived from the granulated product supplied to the lower part of the slag at each holding time.

Embodiments for Carrying Out the Invention

[0011] (Embodiment) FIG. 1 is a diagram schematically showing the configuration of an autogenous furnace 100 located at a copper smelting furnace. As shown in FIG. 1, the autogenous furnace 100 includes a reaction shaft 1 where concentrate and reaction gas are mixed, a settler 2, and an uptake 3. A concentrate burner 4 is provided at the ceiling of the reaction shaft 1. The concentrate burner 4 supplies a main reaction blast gas, an auxiliary reaction gas, and a dispersion gas (which also contributes to the reaction) into the reaction shaft 1 together with copper concentrate, a solvent, recycled raw materials, etc. (hereinafter, these solid raw materials are referred to as smelting raw materials). For example, the main reaction blast gas and the auxiliary reaction gas are oxygen-enriched air, and the dispersion gas is air or oxygen-enriched air.

[0012] Figure 2 is an illustrative diagram illustrating the details of the concentrate burner 4, and is an explanatory diagram showing the input section 10 into which the smelting raw materials, main reaction blower gas, auxiliary reaction gas, and dispersion gas are introduced to the reaction shaft 1.

[0013] The input section 10 of the concentrate burner 4 is equipped with a lance 16, which has a first passage 11 through which dispersion gas passes and a fourth passage 14 through which reaction auxiliary gas passes. The fourth passage 14 is located in the center of the lance 16, and the first passage 11 is located around the fourth passage 14. The input section 10 also has a second passage 12, which serves as a raw material flow path, located outside the lance 16, more specifically on the outer circumference of the lance 16. The input section 10 further has a third passage 13, located outside the second passage 12, more specifically on the outer circumference of the second passage 12, through which the main reaction blower gas passes. The third passage 13 is formed by a tubular portion that surrounds the second passage 12 and is connected to a funnel-shaped air chamber 17 located above it. The second passage 12 and the third passage 13 are separated by a cylindrical partition wall 21.

[0014] The first passage 11 supplies dispersion gas into the reaction shaft 1. The second passage 12 supplies concentrate into the reaction shaft 1. The third passage 13 supplies the main reaction blowing gas from the air chamber 17 into the reaction shaft 1. The fourth passage 14 supplies auxiliary reaction gas into the reaction shaft 1.

[0015] Furthermore, a hollow, frustoconical dispersion cone 15 is formed at the tip (lower end) of the lance 16. Multiple supply holes 152 are formed on the lower side 151 of the dispersion cone 15 to discharge the dispersion gas that has passed through the first passage 11 into the reaction shaft 1. The supply holes 152 are arranged so that the direction of gas discharge is normal to the bottom circle of the dispersion cone 15.

[0016] When the smelting raw materials are introduced into the reaction shaft 1 from the concentrate burner 4, the copper concentrate containing sulfides undergoes an oxidation reaction according to the reaction equation (1) below, and separates into matte 5 and slag 6 (slag solution) at the bottom of the reaction shaft 1, as illustrated in Figure 1. In the reaction equation (1) below, Cu2S·FeS corresponds to the main component of matte 5, and FeO·SiO2 corresponds to the main component of slag 6. Silicate is used as the solvent. CuFeS2 + SiO2 + O2 → Cu2S·FeS + FeO·SiO2 + SO2 + Reaction heat (1)

[0017] Recycled materials may contain metallic components. If the amount of metallic components is small, they will sulfurize and become matte 5 during the process of falling from the concentrate burner 4. Therefore, a metallic phase will not be formed.

[0018] However, as the amount of recycled materials processed increases, the proportion of metallic components (for example, metallic Cu) in the smelting materials tends to increase. In recent years, the proportion of metallic Cu in the Cu component of smelting materials can be between 6.0 mass% and 28.0 mass% or between 9.0 mass% and 18.0 mass% or between 9.0 mass% and 12.0 mass%. In the following explanation, metallic Cu will be described as an example of a metallic component contained in recycled materials, but this explanation can also be applied to other metallic components that form a matte through sulfidation.

[0019] As the proportion of metallic Cu in the smelting raw material increases, the metallic Cu cannot be completely sulfidized during the fall from the concentrate burner 4 and falls as metallic Cu. In matte 5, metallic Cu dissolves in matte 5 to a certain extent, but there is a limit to its dissolution. Figure 3 is a phase diagram showing the solubility of Cu in matte at 1250°C. In Figure 3, "matte(l)" indicates the range in which metallic Cu can dissolve in matte. "matte(l) + Cu(l)" indicates the range in which metallic Cu cannot dissolve in matte and the metallic phase is formed. Note that the phase diagram in Figure 3 is based on "Takako, Koshi, Yazawa, Akira 1983 Selected Research Bulletin".

[0020] Therefore, it is conceivable to introduce powdered sulfur-containing material into the reaction shaft 1 to sulfurize the metallic Cu contained in mat 5 and form a mat. However, when powdered sulfur-containing material is introduced into the reaction shaft 1, there is a risk that the sulfur component will volatilize into the gas phase, causing the sulfur-containing material to desulfurize. In addition, there is a risk that the powdered sulfur-containing material may be captured by the slag 6 floating on the mat 5 and not reach the mat 5. Therefore, it is conceivable to supply the sulfur-containing material by injection using an inert gas as a carrier. However, this method is difficult to operate and presents many challenges.

[0021] Therefore, in this embodiment, a granulated material obtained by mixing a recycled raw material containing metallic Cu and a powdered sulfur-containing material in a predetermined mixing ratio and pressurizing it is introduced into the reaction shaft 1. When mixing metallic Cu and sulfur-containing material, a lower limit is set for the specific surface area of ​​metallic Cu.

[0022] By using granules, the specific surface area of ​​the powdered sulfur-containing material in contact with the atmosphere inside the reaction shaft 1 is reduced. As a result, as illustrated in Figure 4, the desorption (volatilization) of sulfur components can be suppressed during the settling process of the granules 30. Furthermore, compared to the case where powdered sulfur-containing material is used, the granules 30 settle more easily in the slag 6 and reach the metallic Cu in the mat 5 more easily. As a result, even if bubbles 31 of sulfur components are generated, the metallic Cu contained in the mat 5 is sulfurized by these bubbles 31 and forms a mat, thus suppressing the desorption of sulfur components into the gas phase. In addition, by setting a lower limit on the specific surface area of ​​metallic Cu, the contact area between the sulfur-containing material and metallic Cu in the granules 30 is increased, promoting the sulfurization reaction of metallic Cu by the sulfur components, forming a mat, and promoting sedimentation in the slag 6.

[0023] As described above, according to this embodiment, the sulfur source can be efficiently reacted with the metallic component in the mat 5 while reducing the loss due to the volatilization of the sulfur source from the sulfur-containing material.

[0024] It is also possible to pressurize only the sulfur-containing material to create granules. In this case, the detachment of sulfur components during the granule's fall process can be suppressed. However, if the sulfur-containing material and the recycled raw material are not mixed, the efficiency of sulfidation of the recycled raw material by the sulfur components in the sulfur-containing material will decrease, and the sulfur components will still detach into the gas phase.

[0025] The timing of introducing the granules 30 into the reaction shaft 1 is not particularly limited, but for example, if a metallic Cu phase coexists in the mat 5, introducing the granules 30 into the reaction shaft 1 will not only mattify the recycled raw materials mixed in the granules 30, but will also mattify the metallic Cu phase to the extent of the solubility of the molten granules 30.

[0026] The above-mentioned granulated material 30 can be obtained by mixing powdered sulfur-containing material with recycled raw materials in a predetermined mixing ratio, and then pressurizing it to form briquettes.

[0027] For example, the granulated product 30 can be obtained using a pelletizer. FIG. 5 is a diagram illustrating the pelletizer 200. As illustrated in FIG. 5, the pelletizer 200 includes a hopper 210, a screw 220, a pair of rolls 230, and the like. The sulfur-containing material and the recycled raw material are charged into the hopper 210. The screw 220 is provided in the hopper 210 and, by rotating, forcibly sends the raw material between the pair of rolls 230.

[0028] Each of the pair of rolls 230 has a substantially cylindrical shape and is configured to be rotatable about a cylinder axis as a rotation axis. The shapes of the pair of rolls 230 are substantially identical. The pair of rolls 230 are arranged such that their rotation axes are parallel to each other and their circumferential surfaces face each other. Each rotation axis of the pair of rolls 230 substantially coincides in the horizontal direction. The pair of rolls 230 rotate in opposite directions to sandwich the sulfur-containing material and the recycled raw material sent from the screw 220 between their circumferential surfaces, forming and dropping the granulated product 30. Note that the roll 230 may have a substantially cylindrical shape as a whole by combining a plurality of segments of the same shape, or may be a member having a substantially cylindrical shape alone.

[0029] When mixing the powdery sulfur-containing material and the recycled raw material, a binder (organic component) may be mixed. For example, starch, molasses, or the like can be used as the binder. By mixing the binder, the effect of improving the product rate and mechanical strength of the granulated product can be obtained.

[0030] From the viewpoint of increasing the contact area between the sulfur-containing material and metallic Cu in the granulated product 30, the specific surface area (surface area per unit volume) of metallic Cu contained in the recycled raw material is preferably 1.2 mm 2 / mm 3 or more, more preferably 2.0 mm 2 / mm 3 or more, and even more preferably 6.0 mm 2 / mm 3It is even more preferable that the above conditions are met. The specific surface area of ​​metallic Cu in the granules 30 can be estimated to have a lower limit based on the area of ​​the largest sphere that passes through the sieve during sieving. For example, in the case of metallic Cu that passes through a 5 mm sieve, the diameter of the largest sphere that passes through the sieve will be 5 mm, and its sphere area will be 78.5 mm². 2 Therefore, if the volume of metallic Cu is less than or equal to the volume of the largest sphere that can pass through a 5 mm sieve, its surface area will be greater than or equal to the area of ​​the sphere, and thus the specific surface area will be 1.2 mm². 2 / mm 3 It can be estimated that the specific surface area is greater than or equal to the above. In the case of metals or alloys other than metallic Cu that sulfide and dissolve into the matte, the mechanism of the sulfide reaction does not change, so it is considered better to have a smaller specific surface area, and therefore it is preferable to have a specific surface area greater than or equal to the above. The method for estimating the specific surface area can also be the same as above.

[0031] For example, recycled materials may be sieved using a sieve with a mesh size of 5 mm or less, and the material below the sieve may be mixed with powdered sulfur-containing material and then pressurized.

[0032] As the powdered sulfur-containing material to be mixed with the recycled raw material, minerals containing FeS minerals (pyrrhotite), FeS2 minerals (pyrite), CuFeS2 minerals (chalcopyrite), FeS·FeS2, etc., and sulfur-containing copper concentrate can be used. When comparing FeS minerals and FeS2 minerals, it is preferable to use FeS2 minerals, which are said to contain more sulfur necessary for matting. Alternatively, as the sulfur-containing material, sulfur-containing slag generated in the ore-dressing process of non-ferrous metal raw materials can be used. For example, tailings generated in the flotation process are an example of sulfur-containing slag. For example, the sulfur content in the powdered sulfur-containing material is approximately 20 mass% to 55 mass%.

[0033] The recycled material mixed with the powdered sulfur-containing material has a higher true density (g / cm³) than the powdered sulfur-containing material. 3It is preferable that the granules have a high apparent density, as this makes it easier to reach the metallic Cu phase contained in the mat 5. It is preferable to adjust the mixing ratio of the powdered sulfur-containing material and the recycled raw material so that the apparent density of the granules 30 is equal to or greater than the density of the slag 6. For example, if the density of the slag 6 is 3.5 (g / cm³) 3 Since it is often around 3.5 (g / cm³), the apparent density of the granules 30 is 3.5 (g / cm³). 3 It is preferable that the granules are greater than or equal to 30. Furthermore, it is preferable that the granules 30 have sufficient mechanical strength to not collapse while falling through the reaction shaft 1.

[0034] For example, the apparent density of a briquette consisting of pure copper concentrate is 3.5 g / cm³. 3 Because it is less than 3.5 (g / cm³), copper concentrate and true density are less than 3.5 (g / cm³). 3 By mixing recycled materials exceeding 3.5 (g / cm³), the apparent density of the granulated material 30 is increased to 3.5 (g / cm³). 3 It is preferable to adjust it to 6.3 (g / cm³) or higher. For example, copper concentrate and true density of 6.3 (g / cm³) 3 By mixing recycled raw materials () in a weight ratio of 1:1.4 and granulating them, an apparent density of 3.6 (g / cm³) is achieved. 3 A granulated material 30 of the following degree can be obtained. Note that true density is the density obtained by excluding the volume of pores present on the surface and inside the object. Apparent density is the density obtained by excluding only the volume of pores leading to the surface of the object, while including the volume of pores inside. The apparent density is measured according to the Japan Powder Industry Technology Association standard SAP02-82 "Method for measuring the apparent density of granulated materials".

[0035] Furthermore, when mixing sulfur-containing material and recycled raw materials, it is preferable to adjust the moisture content of the mixture to a predetermined range to obtain granules, and then dry the granules 30. In this case, the mechanical strength of the granules 30 is increased, and even if an impact occurs when dropping them into the molten metal, the collapse of the granules 30 can be suppressed. For example, when mixing sulfur-containing material and recycled raw materials, it is preferable to adjust the moisture content to 1 mass% or more to obtain granules 30, and then dry the granules 30. For example, it is preferable to adjust the moisture content of the granules 30 to a predetermined range by mixing copper concentrate containing moisture with dried recycled raw materials.

[0036] On the other hand, if the moisture content of the granules 30 is high, the release properties from the rolls 230 of the granule milling machine 200 may deteriorate, potentially leading to a decrease in yield. Therefore, it is preferable to set an upper limit on the moisture content of the granules 30. In this embodiment, it is preferable to adjust the moisture content of the granules 30 to 6 mass% or less.

[0037] If the diameter of the granules 30 is small, the surface area of ​​the granules 30 may not be sufficiently reduced. Therefore, it is preferable to set a lower limit on the average diameter of the granules 30. On the other hand, if the diameter of the granules 30 is large, the mechanical strength may decrease due to the increase in the weight of the briquettes. Therefore, it is preferable to set an upper limit on the average diameter of the granules 30. In this embodiment, the average diameter of the granules 30 in the longitudinal direction is preferably 20 mm or more and 50 mm or less, or 20 mm or more and 100 mm or less. [Examples]

[0038] The weighed raw materials were mixed and fed into the hopper of a granulator to obtain granules by briquetting. A melting test was conducted by dropping the obtained granules into molten slag, and the composition and weight changes of the granules before and after melting were measured to understand the mass balance of the granules before and after melting and to evaluate the residual rate of sulfur components in the granules. In addition, the melting behavior of the granules was observed when they were dropped. The residual rate of sulfur components in the granules is calculated by subtracting the proportion of sulfur components contained in the granules that were not used for sulfidation of metal elements and instead volatilized as gas. The higher the sulfur residual rate, the more efficiently the sulfur components can react with metallic components while reducing losses due to sulfur desorption.

[0039] In Example 1, powdered copper concentrate and metallic Cu spheres (with a diameter of 0.300 cm and a specific surface area of ​​2.0 mm²) were used. 2 / mm 3 Granules were prepared by kneading () and forming briquettes.

[0040] In Example 2, powdered copper concentrate and metallic Cu powder (with a diameter of 0.00360 cm and a specific surface area of ​​167 mm²) were used. 2 / mm 3 Granules were prepared by kneading () and forming briquettes.

[0041] In the comparative example, granules were prepared by briquetting powdered copper concentrate.

[0042] In all of Examples 1 and 2 and the Comparative Example, cylindrical granules with a diameter of 20 mm and a weight of approximately 10 g were prepared, and their exact weight was then measured. The apparent density of the granules obtained in Example 1 was 4.3 g / cm³. 3 The apparent density of the granules obtained in Example 2 was 3.9 g / cm³. 3 The apparent density of the granules obtained in the comparative example was 3.3 g / cm³. 3 The conditions for Examples 1 and 2 and the comparative example are shown in Table 1. [Table 1]

[0043] Next, as shown in Figure 7, the slag 52 in the alumina tamman tube 51 was heated to 1250°C. Then, the granulated material 30 was dropped from the top of the alumina tamman tube 51 and held for a predetermined time. After that, the alumina tamman tube 51 was cooled with argon and then water-cooled. After drying the alumina tamman tube 51, it was crushed, and the sediment derived from the granulated material 30 was removed from the bottom of the alumina tamman tube 51. After measuring the weight of the sediment, a compositional analysis was performed using EPMA.

[0044] Figure 8 shows the weight of the granulated material sediment supplied to the bottom of the slag at each holding time. As shown in Figure 8, the sedimentation of the granules in the slag was almost completed in 10 minutes in the comparative example, 5 minutes in Example 1, and 3 minutes in Example 2, confirming that the passage time through the slag is shortened by the mixing of metallic Cu.

[0045] Next, the residual rates of each component were measured when the granulated material 30 was dropped into slag 52 and held for 60 minutes. The results are shown in Table 2. As shown in Table 2, in the comparative example, the residual rate of sulfur decreased significantly, and 43.2% of the total sulfur component in the granulated material was desorbed into the gas phase. This is thought to be because, since the sulfur-containing material and the recycled raw material were not mixed, the sulfur component of the sulfur-containing material was not used for sulfidation in the recycled raw material and instead volatilized. [Table 2]

[0046] In contrast, in Examples 1 and 2, almost no detachment of sulfur components from the granules was observed. This is thought to be because the granules were made from sulfur-containing material and metallic Cu. Furthermore, it was confirmed that conditions where metallic Cu has a large specific surface area and the contact area between Cu and sulfur-containing material in the granules is large are advantageous for supplying the granules into the slag.

[0047] The embodiments described above are preferred examples of the present invention. However, the invention is not limited thereto, and various modifications are possible without departing from the spirit of the invention. In this specification, we focus on the Cu metal phase in matte as an example, but the present invention can also be applied to other metals. For example, when feeding recycled raw materials containing a large amount of Fe as a metallic component into a smelting furnace, the present invention can be implemented regardless of whether or not there is phase separation of the metal phase in the matte.

[0048] According to one embodiment of the present invention, it may be possible to contribute to Goal 9 of the United Nations Sustainable Development Goals (SDGs), "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation," through contributions to technological innovation in copper smelting. Furthermore, according to one embodiment of the present invention, it may be possible to contribute to Goal 12 of the United Nations Sustainable Development Goals (SDGs), "Ensure sustainable consumption and production patterns," through the promotion of the use of recycled materials. [Explanation of Symbols]

[0049] 1. Reaction shaft 2 Set Ra 3 Uptake 4. Concentrated Ore Burner 5 mat 6 slags 10 Input section 11 1st aisle 12 2nd aisle 13 3rd aisle 14 4th aisle 16 Lance 17 Air Chamber 21 Partition wall 30 Granules 100 Flash furnace 151 Lower side 152 Supply hole 200 mining machines 210 Hopper 220 Screw 230 rolls 240 Lumps

Claims

1. A method for processing recycled raw materials in a copper smelting furnace, wherein granules obtained by mixing a sulfur-containing material with the recycled raw materials in a predetermined mixing ratio and pressurizing them are introduced into the copper smelting furnace, The recycled material contains metallic metals that sulfide to form a matte, A method for operating a copper smelting furnace, comprising setting a lower limit on the specific surface area of ​​the metallic metal used in the granulated material.

2. The lower limit of the specific surface area is 1.2 mm ２ / mm ３ The method for operating a copper smelting furnace as described in claim 1, wherein the above is achieved.

3. A method for operating a copper smelting furnace according to claim 1, comprising sieving the recycled raw material with a sieve of 5 mm or less, mixing the sieved portion with the sulfur-containing material, and pressurizing it.

4. The method for operating a copper smelting furnace according to claim 1, wherein the sulfur-containing substance is copper concentrate.

5. The method for operating a copper smelting furnace according to claim 1, wherein the recycled material is a metal.

6. The method for operating a copper smelting furnace according to claim 5, wherein the metal is copper.

7. The granulated material according to claim 1, wherein the copper smelting furnace is a self-smelting furnace.

8. A method for processing recycled raw materials in a copper smelting furnace, wherein granules obtained by mixing a sulfur-containing material with the recycled raw materials in a predetermined mixing ratio and pressurizing them are introduced into the copper smelting furnace, The recycled material contains metallic metals that sulfide to form a matte, The specific surface area of ​​the metallic metal used in the granules is 1.2 mm². ２ / mm ３ The above describes the operating method of a copper smelting furnace.

9. A method for operating a copper smelting furnace according to claim 8, comprising sieving the recycled raw material with a sieve of 5 mm or less, mixing the sieved portion with the sulfur-containing material, and pressurizing it.

10. Sulfur-containing material, with a specific surface area of ​​1.2 mm² ２ / mm ３ Granules obtained by mixing recycled raw materials containing the above metallic metals in a predetermined mixing ratio and applying pressure.

11. Apparent density (g / cm³) ３ The granulated material according to claim 10, wherein the ratio is 3.5 or higher.

12. The granulated product according to claim 10, wherein the sulfur-containing substance is copper concentrate.

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