KR20080001580A - Operation method of copper smelting - Google Patents

Abstract

A method for smelting copper is provided to recollect PGM elements by processing recycling material containing at lest one PGM element in a flash smelting furnace. A method for smelting copper comprises a step of providing recycling material, which contains at lest one PGM element, through a blowing hole formed in an electric furnace or an anode furnace. The recycling material directly makes contact with white mat or blister copper, so that precious metal of blister copper is concentrated. The recycling material has a granularity of less than 3mm and is dried under the humidity of less than 2 weight %. The recycling material is put into the electric furnace in a step of manufacturing copper.

Description

OPERATION METHOD OF COPPER SMELTING}

1 shows a plant for blowing regenerated raw materials containing at least one PGM element into a converter in accordance with an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings

1. Blowing tank 2. Compressor

3. exhaust separator 4. dryer

6. Blowing hole 7. Melting

10. Converter 11. Blower

The present invention relates to a method of operating copper smelting, and more particularly, to a method for treating precious metals in a converter or anode furnace used in the copper smelting process.

Various processes are performed as a smelting process of copper sulfide concentrate. Representative processes include smelting copper sulphide concentrate concentrates to produce mats in flash furnaces, etc., treating the mats in converters to produce crude copper having a copper content of about 98.5 mass%, and the copper content of 99.3 mass% to 99.5 masses. Purifying crude copper at the anode to improve to%, casting refined copper to the anode, and finally electrolytically purifying the anode to produce an electrolytic copper having a purity of at least 99.99% by mass. In this process, precious metals such as gold, silver, and platinum contained in the raw materials are concentrated in sludge generated during electrolytic refining.

Precious metals are used for ornaments, lead frames in ICs, catalysts for automotive exhaust gases, exhaust gas sensors, dental materials and the like. Precious metals are recycled in two forms: scrap metal or various industrial wastes. Wet recovery processes apply to precious metal scrap (see Japanese Resource and Materials Society, Special Edition on Regeneration, page 1115-1117). It is known from the above reclaimed special editions, pages 1173-1174, that industrial wastes containing precious metals are fired, sorted and then returned to the copper smelting process.

The copper concentrate, flux component and recycled raw materials in powder form are blown with oxygen into the shaft of the furnace for the reaction to form the mat and slag immediately. The mat and slag accumulate in the furnace and are then separated into upper and lower layers by specific gravity differences.

The mat produced in the smelter is treated in the converter to obtain the next conversion. In other words, iron contained in the mat is oxidized, the resulting oxide is separated into slag phase, and sulfur combined with iron in the mat is separated into gas phase. Thus, white mat occurs in the slag manufacturing process. In the following copper manufacturing process, the sulfur of the white mat is separated into the gas phase and coarse copper is generated.

The coarse produced in the converter is subjected to oxidation and reduction steps in the anode to remove excess sulfur and oxygen. The purified copper is cast into an anode of a suitable shape for electrolytic purification.

The platinum group element shown here means Pt, Pd, Rh, Ru, Ir, and Os, and it is called PGM hereafter. To date, raw materials in the form of powders of lmm or less, including PGM, have been charged to the furnace with copper concentrates and fluxes. Since PGM contained in the raw powder has affinity with Cu in hot melt, most PGM is contained in the anode and is electrolytically separated from the Cu as sludge. The sludge is then subjected to a known purification process for recovering each PGM element individually.

Japanese Laid-Open Patent Publication No. 57-32339, which is named for the operation method of the smelting converter, describes charging of silicate or silica through the tuyeres' tuyere. However, this publication does not mention the step of blowing recycled raw materials through the tuyeres.

Japanese Laid-Open Patent Publication No. 57-192233, which is a method of operating a smelting converter, restricts raw materials charged into a converter through a tuyere to concentrates or concentrates in powder form and smoke dust generated during smelting. However, this publication does not mention the step of blowing recycled raw materials through the tuyeres.

The present inventors have investigated in detail the behavior of recycled raw materials including PGM charged into the furnace, and found the following facts. When most of the PGM's powder and granular form raw materials are charged into the furnace, about 10% of the elements of each PGM are transferred to slag. As mentioned above, the raw materials charged into the use furnace cause a reaction and are then separated into a mat containing copper and a slag containing most impurities. The mat and the slag are separated into the lower layer and the upper layer, respectively, by specific gravity difference. Most of the copper and precious metals transferred to the slag are not recovered and are lost.

Since ultrafine particles in the PGM, such as abrasive powders of ornaments and dental alloys, have a slow settling rate in the slag in the furnace, it is believed that the PGM does not contact the underlying mat and the PGM is moved into the slag. Slag containing PGM is discharged from the furnace. Furthermore, since PGM has a high melting point, the melting time is long.

The present inventors thought that by injecting the raw materials into the molten white mat or the molten crude copper through the tuyeres to the converter or the anode, a direct reaction between the white mat or the crude copper and the PGM can be achieved, and the PGM recovery rate can be improved.

Accordingly, it is an object of the present invention to treat recycled raw materials comprising at least one PGM, i.e., Pt, Pd, Rh, Ru, Ir, and Os elements, so that the lost PGM is recovered in order to improve the recovery of PGM. To improve the operation of copper smelting.

Means to solve the problem

According to the object of the present invention, regenerated raw materials containing at least one PGM element are not charged into the furnace, but are charged into the converter or anode by the following method.

(1) As a copper smelting operation method, recycled raw materials in the form of powder or granules containing one or more PGM elements are blown through the tuyeres of the converter or the anode, and are directly contacted with the white mat or the crude copper to obtain precious metals of the crude copper. It is characterized by concentrating.

(2) The copper smelting operation method according to (1), wherein the recycled raw material containing at least one PGM element has a particle size of 3 mm or less and is dried to 2 mass% or less of moisture.

(3) The copper smelting operation method according to the above (1) or (2), wherein the recycled raw material containing at least one PGM element is blown through at least one selected tuyeres of a converter or an anode.

(4) The copper smelting operation method according to any one of (1) to (3) above, wherein the recycled raw material containing at least one PGM element is blown into the converter during the copper manufacturing step.

Implement the invention  Best form for

The recycled raw material treated by the method of the present invention contains at least one PGM element, that is, Pt, Pd, Rh, Ru, Ir, and Os. The content of each element is usually several ppm to several mass%, especially 1 ppm to 5 mass%. More preferably, the Pt content is 50 g / t (50 ppm) to 1000 g / t (0.1%) and the Pd content is 100 g / t (100 ppm) to 5000 g / t (0.5%).

The recycled raw material may have any composition, which may be smelted in a converter or anode and its PGM may be selected from the majority of the recycled raw materials. Since recycled raw materials originate from almost all industries, it is difficult to specify the components of recycled raw materials. Examples of PGM balances include metals, such as 0 to 95 mass% of Fe, Cu, Al, etc., oxides of 0 to 95 mass% of the metals, 0 to 95 mass% of Fe and Cu, SiO ₂ from industrial waste. , Sulfides of Al ₂ O ₃ , and from 0 to 95 mass% of calcined plastics.

The characteristics of the recycled raw material should be such that the blower tube is not blocked. Therefore, the recycled raw material must be pre-dried to a humidity of 10 mass% or less, and any coarse particles or pieces of the recycled raw material must be pre-purified to 3 mm or less. Drying is carried out by, for example, a steam dryer at a temperature of 100 to 150 ° C. In order to remove the foreign matter mixed with the recycled raw material, a sieve for adjusting the size of the recycled raw material is used.

In an embodiment in which the recycled raw material is blown into the PS converter, the recycled raw material is preferably not blown during the slag forming step in which the slag and the white mat coexist in the furnace, and are blown during the copper manufacturing step in which the white mat and the coarse copper co-exist. To avoid the movement of the PGM into the slag and consequently the loss of the PGM. It is preferable to blow recycled raw materials in the same manufacturing step for the following specific reasons. Since the slag production step is relatively short at about 1 hour, while the copper production step is relatively long at about 3 hours, the melting time of the PGM can be maintained for a long time by blowing regenerated raw materials during the copper production step. Moreover, recycled raw materials blown during the slag production step but cannot be melted are moved into the slag and lost, while recycled raw materials blown in the manufacturing step and not completely melted are moved into the mush. In the next converter operation, the mush, which is fed from a smelting furnace, for example a porcelain furnace, and is moved back into the mat, works strongly with the mat.

The furnace for treating the recycled raw material is either a smelting furnace of a mat, such as a PS converter, or a subsequent refinery, such as, for example, an anode. The anode is used when the amount of recycled raw material is small, and when the amount of impurities that adversely affect the subsequent electrolytic purification process is low. Anode furnaces are less desirable than converters to treat recycled raw materials because they are one of the last steps to make an anode, and the impurity added to the anode raw material from the recycled raw material must be subsequently removed. Because.

A plurality of tuyeres for blowing the recycled raw material are determined according to the amount of the recycled raw material, which may be one or a plurality. The diameter of the tuyere is usually 42.9 to 50.8 mm. The appropriate amount of recycled feed blown per operation can be from about 0.5 to 5 tonnes.

Example

Example 1

A total of 10 tonnes of recycled raw material was tested for four days using converters operating for commercial copper products. One tonne of recycled material is blown into the converter during each operation.

1 shows a facility for testing.

The average data of the test for 4 days is described below.

The recycled raw material comprises 299 g / t Pt and 1644 g / t Pd. Other components of the recycled raw materials are metal elements: 19% Si, 14% Al, 11% Ba, 9% Fe, 5% Ca, 4% S, 4% Ni, 3% Cu, 3% Zn. The recycled raw material was sorted to 3 mm or less, dried at 135 ° C using a steam dryer to 2% by mass or less, sometimes to 10% by mass, and then accumulated in the blowing tank 1. The high pressure air generated in the compressor 2 is conveyed through the discharge separator 3 and the dryer 4 at a rate of 7.8 Nm 3 / min and used as a carrier gas of the recycled raw material at a rate of 5 to 50 kg / min. . The contained solid air mixture is blown into the molten metal 7 by the tuyeres 6, and the molten metal is formed at the same manufacturing step, and the white mat and the coarse copper coexist. Clogging of the blower pipe 11 does not occur. Moreover, upon blowing up the solid air mixture described above, no steam expansion occurs in the converter 10.

The balance of Pt and Pd is shown in FIG. 1, and the amount of Pt and Pd to be blown is assumed to be 100% each.

TABLE 1

 Precession  Converter dust  Converter slag  Pt transfer rate (%)  98.6  1.1  0.3  Movement ratio of Pd (%)  98.1  0.5  1.4

All of the cradle goes into the ladle and then flows into the anode. The converter slag is partially left in the converter, and the next converter operation begins to rebuild the converter slag. The sum of the remaining slag and the re-formed slag enters the next operation. Converter slag in Table 1 represents this total slag.

As shown in Table 1, 98.6% of Pt and 98.1% of Pd in the reclaimed raw materials were transferred to the coarse formed in the converter. This ratio represents a more efficient recovery than charging recycled raw materials into previous furnaces. The rate of movement into the slag is about 10% of charging into the slag. Cu grades of the resulting coarseness were common.

Example 2

The same 5 tonnes of recycled material as in Example 1 is blown into the anode for commercial copper products. The balance of Pt and Pd is shown in Table 2. Cu grade of the refined copper of the result was general.

TABLE 2

 Refinery  Dust as anode  Pt transfer rate (%)  99.6  0.4  Movement ratio of Pd (%)  99.7  0.3

Industrial availability

In the case of processing regenerated raw materials containing PGM in the smelting process, the regenerated raw materials are charged into the converter or anode furnace. In this case, the recycled raw material does not directly contact the slag. Therefore, slag loss of PGM can be avoided, and a recovery rate of PGM of 98% or more is obtained.

According to this configuration of the present invention, recycled raw materials containing one or more PGM (i.e., Pt, Pd, Rh, Ru, Ir, and Os) elements are used for the purpose of recovering the lost PGM to improve the recovery of PGM. It is possible to improve the method of operation of copper smelting, which is treated in.

Claims (5)

In the copper smelting operation method, a regeneration raw material in powder or granular form containing one or more elements of platinum group elements, namely Pt, Pd, Rh, Ru, Ir, and Os (hereinafter referred to as PGM) is converted into a converter or anode (s). A copper smelting operation method, characterized in that it blows through the tuyere of ()) and directly contacts with a white mat or crude copper, and the precious metal of copper is concentrated. The copper smelting operation method according to claim 1, wherein the recycled raw material containing the at least one PGM element is 3 mm or less and dried at a humidity of 2% by mass or less. 3. The smelting operation method according to claim 1 or 2, wherein the reclaimed raw material containing the at least one PGM element is blown through at least one selected tuyeres of a converter or an anode. The copper smelting operation method according to claim 1 or 2, wherein the regeneration raw material containing the at least one PGM element is blown into a converter during the copper manufacturing step. 4. The copper smelting operation method according to claim 3, wherein the recycled raw material containing the at least one PGM element is blown into the converter during the copper manufacturing step.

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