Method of operating a copper smelting furnace, mixture, and method of producing the mixture

Abstract

The present invention provides a method for operating a copper smelting furnace, a mixture, and a method for producing the mixture, which enable efficient reaction of sulfur components with metallic components while reducing losses due to the desorption of sulfur components. [Solution] The copper smelting operation method includes the step of introducing a mixture obtained by mixing a sulfur-containing substance and recycled raw materials in a predetermined mixing ratio into a copper smelting furnace, wherein the mixing ratio of the sulfur-containing substance and the recycled raw materials in the mixture is such that, in the environment of the copper smelting furnace, all of the metallic components contained in the recycled raw materials can be matted by the sulfur components of the sulfur-containing substance.

Description

[Technical Field]

[0001] The present invention relates to a method for operating a copper smelting furnace, a mixture, and a method for producing the mixture. [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 Initiative] [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 needed to mattify the metallic components. In conventional self-smelting furnaces, most of the sulfur components in the copper concentrate supplied from the concentrate burner react with oxygen in the reaction shaft and are discharged outside the furnace as sulfur dioxide gas. Therefore, in order to maximize the use of the sulfur components in the copper concentrate for matting the metallic components, measures are needed to suppress the desorption of sulfur components in the reaction shaft.

[0005] This invention has been made in view of the above problems, and aims to provide a method for operating a copper smelting furnace, a mixture, and a method for producing a mixture that can efficiently react sulfur components with metallic components while reducing losses due to the desorption of sulfur components. [Means for solving the problem]

[0006] The copper smelting operation method according to the present invention includes the step of introducing a mixture obtained by mixing a sulfur-containing material and recycled raw materials in a predetermined mixing ratio into a copper smelting furnace, wherein the mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture is such that, in the environment of the copper smelting furnace, all metallic components contained in the recycled raw materials can be matted by the sulfur components of the sulfur-containing material. The mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture may also be such that, when considering only the Cu, Fe, and S components in the mixture, its average composition falls within the matte single-phase region on the Cu-Fe-S phase diagram. The mixture may be obtained by mixing powdered sulfur-containing material with recycled raw materials obtained as sieve residue by passing it through a sieve with a maximum mesh size of 10 mm or less, in a predetermined mixing ratio, and then pressurizing the mixture. The apparent density of the mixture (g / cm³) 3 ) may be 3.5 or higher. The sulfur-containing substance may be copper concentrate.

[0007] The mixture according to the present invention is a mixture for input into a copper smelting furnace, wherein a sulfur-containing material and recycled raw materials are mixed in a predetermined mixing ratio, and the mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture is such that, in the environment of the copper smelting furnace, all metallic components contained in the recycled raw materials can be matted by the sulfur components of the sulfur-containing material. The mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture may also be such that, when considering only the Cu, Fe, and S components in the mixture, the average composition falls within the matte single-phase region on the Cu-Fe-S phase diagram. The particle size in the long axis direction of the recycled raw materials in the mixture may be less than 50 mm. The apparent density of the mixture (g / cm³) 3) may be 3.5 or higher. The sulfur-containing substance may be copper concentrate.

[0008] The method for producing a mixture according to the present invention is a method for producing a mixture to be fed into a copper smelting furnace, and includes a step of mixing a sulfur-containing material and recycled raw materials in a predetermined mixing ratio, wherein the mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture is such that, in the environment of the copper smelting furnace, all metallic components contained in the recycled raw materials can be matted by the sulfur components of the sulfur-containing material. The mixing ratio of the sulfur-containing material and the recycled raw materials in the mixture may also be such that, when considering only the Cu, Fe, and S components in the mixture, its average composition falls within the matte single-phase region on the Cu-Fe-S phase diagram. The mixture may also be obtained by passing powdered sulfur-containing material through a sieve with a maximum mesh opening of 10 mm or less, mixing it with the recycled raw materials obtained as sieve residue in a predetermined mixing ratio, and then pressurizing the mixture. The apparent density of the granulated product (g / cm³ 3 The apparent density (g / cm³) of the mixture may be adjusted to be greater than or equal to the density of the slag solution produced in the copper smelting furnace. 3 The water content may be adjusted to 3.5 or higher. The sulfur-containing material may be copper concentrate. The mixture may be obtained by adjusting the water content to a predetermined range when mixing the sulfur-containing material and the recycled raw material, and then drying the mixture. The water content may be 1 mass% or more and 6 mass% or less. The sulfur-containing material is copper concentrate, and the water content may be adjusted to the predetermined range by mixing the sulfur-containing material containing water with the dried recycled raw material. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a method for operating a copper smelting furnace, a mixture, and a method for producing the mixture, which can efficiently react sulfur components with metallic components while reducing losses due to the desorption of sulfur components. [Brief explanation of the drawing]

[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 exemplifying the details of the concentrate burner 4. [Figure 3] It is a phase diagram showing the solubility of Cu in the matte. [Figure 4] It is a diagram exemplifying the fall of the granulated material. [Figure 5] It is a diagram exemplifying the pelletizer. [Figure 6] It is a diagram exemplifying the fall of the granulated material. [Figure 7] It is a diagram for explaining an example.

Embodiments for Carrying Out the Invention

[0011] (Embodiment) Figure 1 is a diagram schematically showing the configuration of an autogenous furnace 100 which is one of copper smelting furnaces. As shown in Figure 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 the reaction shaft 1 with copper concentrate, flux, recycled raw materials, etc. (hereinafter, these solid raw materials are referred to as smelting raw materials), together with the main reaction blower gas, the auxiliary reaction gas, and the dispersion gas (which also contributes to the reaction). For example, the main reaction blower gas and the auxiliary reaction gas are oxygen-enriched air, and the dispersion gas is air or oxygen-enriched air.

[0012] Figure 2 is a diagram exemplifying the details of the concentrate burner 4, and it is an explanatory diagram showing an input section 10 for inputting smelting raw materials, the main reaction blower gas, the auxiliary reaction gas, and the dispersion gas to the reaction shaft 1 side.

[0013] The charging section 10 of the concentrate burner 4 includes a lance 16. Inside the lance 16, a first passage 11 through which the dispersion gas passes and a fourth passage 14 through which the auxiliary reaction gas passes are formed. The fourth passage 14 is provided in the central portion of the lance 16, and the first passage 11 is provided around the fourth passage 14. Further, the charging section 10 includes a second passage 12 as a raw material flow path provided outside the lance 16, more specifically, on the outer periphery of the lance 16. The charging section 10 further includes a third passage 13 provided outside the second passage 12, more specifically, on the outer periphery of the second passage 12, through which the main blowing gas for reaction passes. The third passage 13 is formed by a tubular portion provided so as to surround the second passage 12 and communicates with a funnel-shaped air chamber 17 provided 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 the dispersion gas into the reaction shaft 1. The second passage 12 supplies the concentrate into the reaction shaft 1. The third passage 13 supplies the main blowing gas for reaction from the air chamber 17 into the reaction shaft 1. Also, the fourth passage 14 supplies the auxiliary reaction gas into the reaction shaft 1.

[0015] At the tip (lower end) of the lance 16, a hollow truncated cone-shaped dispersion cone 15 is formed. On the lower part 151 of the side surface of the dispersion cone 15, a plurality of supply holes 152 for discharging the dispersion gas passing through the first passage 11 into the reaction shaft 1 are formed. The supply holes 152 are provided such that the gas discharge direction is the normal direction of the bottom circle of the dispersion cone 15.

[0016] When the smelting raw material is charged into the reaction shaft 1 from the concentrate burner 4, the copper concentrate containing sulfide undergoes an oxidation reaction according to the following reaction formula (1) etc., and as illustrated in FIG. 1, it separates into a matte 5 and a slag 6 (slag melt) at the bottom of the reaction shaft 1. In the following reaction formula (1), Cu2S·FeS corresponds to the main component of the matte 5, and FeO·SiO2 corresponds to the main component of the slag 6. A silicate ore 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 the same explanation can be applied to other metallic components as well.

[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 mixture obtained by mixing powdered sulfur-containing material and recycled raw material in a predetermined mixing ratio is introduced into the reaction shaft 1. When the mixture melts, the sulfur components released from the sulfur-containing material sulfurize the recycled raw material, thereby suppressing the release of sulfur components from the sulfur-containing material into the gas phase. This allows the sulfur components to react efficiently with the metallic components while reducing losses due to the release of sulfur components. Furthermore, the mixing ratio of the sulfur-containing material and recycled raw material in the mixture is set so that, in the environment of the reaction shaft 1, all of the metallic components contained in the recycled raw material are matted by the sulfur components of the sulfur-containing material. This allows the sulfur components to react efficiently with the metallic components, and the metallic components can be matted.

[0022] For example, if the average composition of the mixture falls within the matte(l) region on the Cu-Fe-S phase diagram shown in Figure 3, it becomes possible to matte all of the metallic Cu in the recycled material, resulting in a sulfur residue rate of approximately 90% or more. The sulfur residue rate is calculated by subtracting the proportion of sulfur in the mixture that was not used for sulfurization of the metal elements and instead volatilized as gas. A higher sulfur residue rate allows for more efficient reaction of sulfur components with metallic components while reducing losses due to sulfur desorption. The same applies to other elements that can be matted. Other elements that can be matted include Fe, whose product phase can be determined on the Cu-Fe-S phase diagram, just like Cu. Other metallic components that may be matted include Pb, Ni, Zn, and Sn, but these elements are usually trace elements and can therefore be ignored.

[0023] Here, we will describe an example of a ratio in the environment within reaction shaft 1 at which all metallic components in the recycled raw material can be matted by the sulfur components of the sulfur-containing material. For example, let's assume that the component grades of the sulfur-containing material are Cu: 30 wt%, Fe: 30 wt%, and S: 40 wt%, and that the component grades of the recycled raw material are Cu: 80 wt%, Fe: 12 wt%, Zn: 2 wt%, Ni: 2 wt%, Pb: 2 ​​wt%, and Sn: 2 wt%. We will assume that the metallic components in the recycled raw material will be converted to Cu2S, FeS, PbS, Ni3S2, ZnS, and SnS through sulfidation.

[0024] For every 100g of sulfur-containing material, the available sulfur supply is 40g, and the sulfur consumption is (30 / 63.5) / 2(Cu) + 30 / 55.8(Fe) = 0.774mol × 32 = 24.8g. Therefore, the amount of sulfur that can be matted from the recycled material is 40 - 24.8 = 15.2g.

[0025] For every 100g of recycled material, the amount of sulfur consumed is (80 / 63.5) / 2(Cu) + 12 / 55.8(Fe) + 2 / 65.4(Zn) + (2 / 58.7) × (2 / 3)(Ni) + 2 / 207.2(Pb) + 2 / 118.7(Sn) = 0.925 mol × 32 = 29.6g.

[0026] Therefore, the amount of recyclable material that can be sulfurized by 100g of sulfur-containing material is 15.2 / 29.6 × 100 = 51.4g. Consequently, in this case, if the sulfur-containing material and recyclable material are mixed in a weight ratio of 1:0.514, it is possible to sulfurize the entire amount of metallic components in the recyclable material.

[0027] For example, it is conceivable to use granules obtained from powdered sulfur-containing material and recycled raw materials. This granule is an example of a mixture obtained by mixing sulfur-containing material and recycled raw materials in a predetermined mixing ratio. By using granules obtained from sulfur-containing material and recycled raw materials, the specific surface area of ​​the powdered sulfur-containing material that comes into 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 falling process of the granules 30. In addition, compared to the case where powdered sulfur-containing material is used, the granules 30 sink more easily into 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 becomes mat, thus suppressing the desorption of sulfur components into the gas phase. When the sulfur components contained in the granules 30 sulfurize the metallic Cu, heat of the sulfurization reaction is generated. This heat of the sulfurization reaction also has the effect of promoting the melting of the granules 30.

[0028] 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.

[0029] The timing for 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 until the mat produced by the melting of the granules 30 can maintain a single mat phase.

[0030] 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.

[0031] For example, granulated material 30 can be obtained using a granule mill. Figure 5 is an example of a granule mill 200. As illustrated in Figure 5, the granule mill 200 is equipped with a hopper 210, a screw 220, a pair of rolls 230, etc. Sulfur-containing material and recycled raw materials are fed into the hopper 210. The screw 220 is located inside the hopper 210 and rotates to forcibly feed the raw materials between the pair of rolls 230.

[0032] Each of the pair of rolls 230 has a substantially cylindrical shape and is configured to rotate around its cylindrical axis as the axis of rotation. The shapes of the pair of rolls 230 are substantially identical. The pair of rolls 230 are arranged so that their axes of rotation are parallel to each other and their circumferential surfaces face each other. The axes of rotation of the pair of rolls 230 are substantially aligned horizontally. The pair of rolls 230 rotate in opposite directions to sandwich the sulfur-containing material and recycled raw material sent from the screw 220 between their circumferential surfaces, forming granules 30 which are then dropped. Note that the rolls 230 may have a substantially cylindrical shape as a whole by combining multiple segments of the same shape, or they may be a single substantially cylindrical member.

[0033] When mixing powdered sulfur-containing material with recycled raw materials, a binder (organic component) may be added. For example, starch, molasses, etc., can be used as a binder. Adding a binder improves the product yield and mechanical strength of the granulated material.

[0034] Alternatively, granules 30 may be obtained by mixing and melting sulfur-containing material and recycled raw materials, and then forming them into a mass.

[0035] 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%.

[0036] As recycled materials for mixing with powdered sulfur-containing substances, copper scrap including metal shavings, dust ash, and electrical component scraps can be used. For example, the average composition of recycled materials is 10 mass% to 95 mass% of Cu, 0 mass% to 50 mass% of Fe, and a total of 0 mass% to 40 mass% of other elements such as Sn, Zn, Pb, and Al. Furthermore, recycled materials can be obtained, for example, by passing them through a sieve with a maximum mesh size of 10 mm or less and analyzing the resulting residue.

[0037] In the granulated product 30, it is preferable that the recycled raw material is obtained as the undersize fraction by passing it through a sieve with a maximum mesh size of 10 mm or less. This is because the smaller the particle size of the recycled raw material to be mixed, the more the product rate, mechanical strength, etc. of the granulated product are improved. Since the recycled raw material includes linear ones, the particle size in the long axis direction may be less than 50 mm.

[0038] The recycled raw material to be mixed with the powdery sulfur-containing substance preferably has a true density (g / cm 3 ) greater than that of the powdery sulfur-containing substance. This is because the apparent density of the granulated product 30 increases, making it easier to reach the metallic Cu phase contained in the mat 5. It is preferable to adjust the mixing ratio of the powdery sulfur-containing substance and the recycled raw material so that the apparent density of the granulated product 30 becomes equal to or greater than the density of the slag 6. For example, since the density of the slag 6 is often about 3.5 (g / cm 3 ), the apparent density of the granulated product 30 is preferably 3.5 (g / cm 3 ) or more. Further, the granulated product 30 preferably has a mechanical strength such that it does not collapse during falling inside the reaction shaft 1.

[0039] For example, since the apparent density of a briquette composed of only copper concentrate is less than 3.5 (g / cm 3 ), it is preferable to mix copper concentrate with a recycled raw material having a true density exceeding 3.5 (g / cm 3 ) and adjust the apparent density of the granulated product 30 to 3.5 (g / cm 3 ) or more. For example, by mixing copper concentrate and a recycled raw material having a true density of 6.3 (g / cm 3 ) at a weight ratio of 1:1.4 and granulating, a granulated product 30 having an apparent density of about 3.6 (g / cm 3 ) can be obtained. The true density is the density obtained by excluding the volume of pores existing on the surface or inside of the object. The apparent density is the density obtained by excluding only the volume of pores leading to the surface of the object and including the volume of internal pores. The apparent density is measured based on the Japan Society of Powder Technology Standard SAP02-82 "Method for Measuring the Apparent Density of Granulated Products".

[0040] 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.

[0041] 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.

[0042] 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.

[0043] Alternatively, a mixture of powdered sulfur-containing material and recycled raw materials can be used, such as a cored wire, which is a mixture of powdered sulfur-containing material and recycled raw materials mixed in a predetermined ratio, or a mixture obtained by encasing only powdered sulfur-containing material in a thin metal sheet and forming it into a continuous wire. [Examples]

[0044] 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 the residual rate of sulfur components in the granules was evaluated. In addition, the melting behavior of the granules was observed when they were dropped into the slag.

[0045] In Example 1, granules were prepared by kneading powdered copper concentrate and metallic Cu powder (diameter 0.036 mm) and briquetting them. The Cu powder / copper concentrate weight ratio, which is the ratio of the weight of Cu powder to the weight of copper concentrate, was set to 0.67.

[0046] In Example 2, granules were prepared by kneading powdered copper concentrate with simulated raw materials (Cu: 80.1 mass, Fe: 11.3 mass, Zn: 4.5 mass, Sn: 2.4 mass, Pb: 1.6 mass%) made from unground parts mill waste, and then briquetting the mixture. The weight ratio of simulated raw materials to copper concentrate was set to 0.65. The simulated raw materials used had a major diameter of 10 mm or less.

[0047] In the comparative example, granules were prepared by briquetting powdered copper concentrate.

[0048] 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 3.9 g / cm³. 3 The apparent density of the granules obtained in Example 2 was 4.1 g / cm³. 3 The apparent density of the granules obtained in the comparative example was 3.3 g / cm³. 3 That was the case.

[0049] Next, as shown in Figure 7, the slag 52 in the alumina tammann tube 51 was heated to 1250°C. Then, the granulated material 30 was dropped from the top of the alumina tammann tube 51 and held for 60 minutes. The dropping process was also visually observed on site. After 60 minutes, the alumina tammann tube 51 was cooled with argon and then water-cooled. After drying the alumina tammann tube 51, it was crushed and the molten granulated material 30 was extracted. After measuring the weight of the molten material, a compositional analysis was performed using EPMA.

[0050] The results are shown in Table 1. As shown in Table 1, in the comparative example, the sulfur residue rate decreased significantly, and 43.2% of the total sulfur content in the granules 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 1]

[0051] In contrast, in Example 1, no desorption of sulfur components from the granules was observed. This is thought to be because the sulfur desorbed from the copper concentrate efficiently contributed to the matting of the Cu powder.

[0052] In Example 2, almost no detachment of sulfur components from the granules was observed. This is thought to be because the sulfur components were used in matting the metallic Cu when the simulated raw material and copper concentrate were mixed.

[0053] 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.

[0054] 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]

[0055] 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. The process includes a step of mixing sulfur-containing material and recycled raw materials in a predetermined mixing ratio and then introducing the resulting mixture into a copper smelting furnace. A method for operating a copper smelting furnace, wherein the mixing ratio of the sulfur-containing substance and the recycled raw material in the mixture is such that, in the environment of the copper smelting furnace, all of the metallic components contained in the recycled raw material can be matted by the sulfur components of the sulfur-containing substance.

2. The method for operating a copper smelting furnace according to claim 1, wherein the mixing ratio of the sulfur-containing substance and the recycled raw material in the mixture is such that, when only the Cu, Fe, and S components in the mixture are considered, the average composition falls within the matt single-phase region on the Cu-Fe-S phase diagram.

3. The method for operating a copper smelting furnace according to claim 1, wherein the mixture is obtained by mixing powdered sulfur-containing material with recycled raw materials obtained as sieve residue by passing it through a sieve with a maximum mesh size of 10 mm or less, in a predetermined mixing ratio, and then pressurizing the mixture.

4. The apparent density (g / cm³) of the mixture ３ The method for operating a copper smelting furnace according to claim 3, wherein the coefficient is 3.5 or higher.

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

6. A mixture to be put into a copper smelting furnace, Sulfur-containing material and recycled raw materials are mixed in a predetermined mixing ratio. The mixing ratio of the sulfur-containing substance to the recycled raw material in the mixture is such that, in the environment of the copper smelting furnace, all of the metallic components contained in the recycled raw material can be matted by the sulfur components of the sulfur-containing substance.

7. The mixture according to claim 6, wherein the mixing ratio of the sulfur-containing substance and the recycled raw material in the mixture is such that, considering only the Cu, Fe, and S components in the mixture, the average composition falls within the matte single-phase region on the Cu-Fe-S phase diagram.

8. The mixture according to claim 6, wherein the particle size of the recycled material in the long axis direction in the mixture is less than 50 mm.

9. The apparent density (g / cm³) of the mixture ３ The mixture according to claim 6, wherein the ratio of ) is 3.5 or higher.

10. The mixture according to claim 6, wherein the sulfur-containing substance is copper concentrate.

11. A method for producing a mixture to be put into a copper smelting furnace, The process includes a step of mixing sulfur-containing material and recycled raw materials in a predetermined mixing ratio. A method for producing a mixture, wherein the mixing ratio of the sulfur-containing substance and the recycled raw material in the mixture is such that, in the environment of the copper smelting furnace, all of the metallic components contained in the recycled raw material can be matted by the sulfur components of the sulfur-containing substance.

12. The method for producing the mixture according to claim 11, wherein the mixing ratio of the sulfur-containing substance and the recycled raw material in the mixture is such that, when only the Cu, Fe, and S components in the mixture are considered, the average composition falls within the matte single-phase region on the Cu-Fe-S phase diagram.

13. A method for producing the mixture according to claim 11, comprising passing a powdered sulfur-containing material through a sieve with a maximum mesh size of 10 mm or less, mixing it with recycled raw materials obtained as a sieve residue at a predetermined mixing ratio, and then applying pressure to obtain the mixture.

14. The apparent density of the granules (g / cm³) ３ A method for producing the mixture according to claim 11, wherein the density is adjusted to be greater than or equal to the density of the slag solution produced in a copper smelting furnace.

15. The apparent density (g / cm³) of the mixture ３ A method for producing the mixture according to claim 14, wherein the ratio is adjusted to 3.5 or higher.

16. The method for producing the mixture according to claim 11, wherein the sulfur-containing substance is copper concentrate.

17. A method for producing a mixture according to claim 11, wherein the water content is adjusted to a predetermined range when mixing the sulfur-containing substance and the recycled raw material to obtain the mixture, and then the mixture is dried.

18. The method for producing the mixture according to claim 17, wherein the water content is 1 mass% or more and 6 mass% or less.

19. The aforementioned sulfur-containing material is copper concentrate. A method for producing a mixture according to claim 17, wherein the water content is adjusted to the predetermined range by mixing the sulfur-containing substance containing water with the dried recycled raw material.

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