JPS61177340A - Treatment of gold-and silver-containing silica ore - Google Patents

Abstract

PURPOSE:To treat efficiently gold- and silver-contg. silica ore and to recover efficiently gold and silver by adding a reducing agent and the gold- and silver- contg. silica ore to copper converter slag, maintaining the slag at an adequate temp., adding a CaO-contg. material thereto and maintaining the adequate CaO grade of the slag. CONSTITUTION:The copper converter slag is maintained at 1,200-1,300 deg.C by a method for blowing pulverized coal and air enriched with oxygen through a tuyere into the molten converter slag or other method to melt the gold- and silver-contg. silica ore and to absorb the gold and silver therein into the separated copper-component, by which the gold and silver are recovered and the refractory erosion of the converter is prevented in a method for treating the above- mentioned ore by adding the reducing agent and said ore into the copper converter slag, melting the slag and absorbing the gold and silver into the recovered copper-component. The CaO-contg. material is added to the slag and is melted to maintain the CaO grade of the slag at about >=3.0wt% and about 13% in the above-mentioned method, by which the slopping of the slag is prevented and the handling loss of the recovered gold and silver is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for dissolving gold-containing silver silicate ore in a copper converter and recovering gold and silver.

[Conventional technology]

As a method of melting gold-containing silver silicate ore and recovering gold, a reducing agent and gold-containing silver silicate ore are added to a copper converter, the gold and silver are absorbed into the copper content in the copper converter, and the copper content is separated. He invented a method of recovering gold and silver by doing this.

This method involves blowing pulverized coal and oxygen-enriched air into the melting converter through the tuyeres, or adding a reducing agent such as coal while maintaining the bath temperature with an auxiliary burner. O is reduced to lower the viscosity of HIME, and the copper suspended in HIME is separated by sedimentation. At the same time, a part of the copper chemically dissolved in HIME is also reduced and recovered, and at the same time, the copper content suspended in HIME is reduced and recovered. F
By adding and dissolving gold-bearing silver silicate ore until e/5in2 becomes about 0.8 and absorbing the gold and silver in the gold-bearing silver silicate ore into the separated copper, the copper and gold-bearing silver silicate in Hime are dissolved. This method simultaneously recovers gold and silver from the ore.

However, with this method, the final composition is FeO-FeO
-The composition of SiO saturation region of SiO system 2 3
2 Additionally, due to a slight temperature drop or compositional change, the added gold-containing silver silicate ore may remain undissolved, resulting in a decrease in the yield of gold and silver.
Because the dissolution rate is slow, a large amount of heat is required to maintain the gold-containing silver silicate ore at high temperatures for a long time to completely dissolve it.
Further, if the temperature is further increased to shorten the melting time, there is a drawback that the refractory material will be significantly damaged by melting. Furthermore, when the reducing agent is injected from the tuyere or top blowing lance using this method, as the gold-containing silver silicate ore dissolves during the converter heating, the heating becomes more intense, causing the heating to flow out of the furnace from the furnace opening. Alternatively, there were safety and equipment maintenance problems such as increased slopping, increased number of repeated objects, and high-temperature solution being blown out.

[Problem that the invention seeks to solve]

The purpose of the present invention is to completely melt the gold-containing silver silicate ore in a short time when reducing the copper converter and melting the gold-containing silver silicate ore while reducing the amount of fuel required to maintain the bath temperature. The object of the present invention is to provide a method for extending the life of refractories and preventing thermal forming sloping.

[Means for solving problems]

The method of the present invention is a method for treating gold-containing silver silicate ore by adding a reducing agent and gold-containing silver silicate ore to a copper converter, dissolving it, and making the recovered copper absorb gold and silver. The purpose is to add and dissolve a CaO-containing substance in the molten metal so that the warm CaO grade becomes a, O weight % or more while maintaining the molten temperature at 1200 to 1300 c.

The inventors established conditions for dissolving converter powder, gold-containing silver silicate powder, limestone powder, and pulverized coal in an alumina Tamman tube on a laboratory scale. 2% by weight
, N gas, 1250C, 1 hour) . That is, Ca
If the O addition rate is less than 2.5% by weight (Hime's CaO grade is 3.0% by weight), the thickness of the millet layer is large and warm forming and slopping are likely to occur, so Hime's CaO grade is 3.0%. It needs to be at least % by weight. However, even if it is contained in a large amount, the effect will not be great, so the CaO grade is limited to about 13% by weight at most.

Either limestone or raw coal can be used as the CaO source, and various methods of adding shape can be considered, but no special method is required.
All you have to do is throw the lumps into the furnace.

If the temperature when melting the gold-containing silver silicate ore is less than 1200 C, slopping will be significant and the gold-containing silver silicate will remain undissolved, and if the temperature exceeds 1300 C, the refractory will be significantly eroded, and Also in this case, since a lot of slopping occurs, the temperature must be set at 1200 to 1300 t:'.

〔Example〕

Example brick lining inner diameter 1.51!1% inner length 1.7 m It
Copper converter furnace with the composition shown in Table 1 for S-type converter 2 to 4 tons
was charged, and the oxygen concentration was 25 to 3 from the four tuyeres of the inner diameter 21
While blowing 3% by volume of oxygen-enriched air (15 to 2ONm15) and 10 to 20% by weight of pulverized coal (1% by weight to the converter), the gold-containing silver silicate ore having the composition shown in Table 1 was poured into the 1st layer (1 ) F
e/SiO is 1. Until the ONO is 8, and the CaO addition rate is 7% by weight (based on the converter), lumpy limestone is collected through a chute inserted into the furnace mouth, and powdery material is collected through the tuyeres or lances. It was charged continuously by blowing method.

After the addition of gold-containing silver silicate and limestone, the furnace was blown for a certain period of time, and then the furnace was tilted and the iron and recovered copper were discharged from the furnace. During these operations, the temperature was controlled at 1200 to 1300 tZ'' by adjusting the alloyed silver silicate ore charging rate, oxygen enrichment blown into the tuyeres, and the oxygen concentration of the air.

As gold-containing silver silicate ore, SiO85.0% by weight, 15
~30 mcg lumps or powder (containing 70% by weight of 200 mcg or less) are used, and 10 to 20 mcg is used as the CaO source.
11! T11 massive limestone was used.

Table 1: Unit Duplex Weight % The recovery rate of gold and silver by this process was about 96 to 98% by weight.

Figure 2 shows the influence of dissolution time and temperature on the dissolution state of gold-containing silver silicate ore. In Figure 2. Marks 6 and 6 are respectively charged with bulk gold-bearing silver silicate ore until the Fe/5in2 of the Hime layer becomes 1.0, and limestone with a CaO addition rate.

This is the case where there was no undissolved gold-containing silver silicate ore during the operation in which the amount was charged to 7% by weight (for the converter), and the cases where there was undissolved gold-containing silver silicate ore. Fe in the Ohime layer
/s1o is 0.8, and limestone is
This is the case where there was no undissolved gold-bearing silver silicate ore during the operation in which charging was carried out until the O addition rate reached 7% by weight (relative to the converter furnace), and the V mark indicates powdery gold-bearing silver. Silica ore is Fe in iron.
/SiO was charged until it reached 1.0, and limestone was charged until the CaO addition rate reached 7% by weight (for the converter furnace), and there was no undissolved gold-containing silver silicate ore. . As can be seen in Figure 2, when the CaO addition rate is 7% by weight, the warm temperature is 120%.
The dissolution state of the gold-containing silver silicate ore is improved by setting Fe/slo to 1.0 at 0 to 1300C, and it is further improved by charging the powdered gold-containing silver silicate ore.

Table 2 shows the effects of CaO addition and temperature control on warm slopping. Table 2 shows that in Example 1.2, the warm temperature was reduced to 120% by adding limestone and adjusting the charging rate of gold-containing silver silicate ore and the oxygen concentration of the oxygen-enriched air used.
The temperature was controlled between 0 and 1300 C, indicating that the amount of material blown up from the converter mouth was reduced and slopping was suppressed.

Table 2 Table 3 shows the effects of CaO addition and M temperature control on the amount of refractory erosion in the converter.

Table 3 In the example shown in Table 3, the temperature was controlled to 1200 to 1300 C by adding limestone and adjusting the charging rate of gold-containing silver silicate ore and the oxygen concentration of the oxygen-enriched air used. This indicates that the amount of refractory welding in each part of the converter was reduced because the temperature was properly controlled and slopping was suppressed.

Comparative Example A comparative example was carried out using almost the same equipment 1 charge and operating method as in the example except for the conditions described below.

In Figure 2, which shows the influence of dissolution time and warm temperature on the dissolution status of gold-bearing silver silicate ore, the marks ○ and ■ indicate the cases in which lumpy gold-bearing silver silicate ore is placed in iron without charging limestone, respectively. Il
This is the case where there was no undissolved gold-containing silver silicate ore during the operation in which charging was carried out until 'e/5in2 became 1.0. As can be seen from Figure 2, under the conditions of this example, i.e., when no limestone is used, the degree of permanence is set at a high temperature of about 13,000 or higher,
This indicates that undissolved gold-containing silver silicate ore tends to remain unless the dissolution time is a long time of about 100 minutes or more.

In Table 2 showing the effects of CaO addition and warm temperature control on slopping, Comparative Example 1 shows no addition of limestone, no oxygen enrichment of the tuyere air, and the slopping temperature. The slopping became significant because the final temperature decreased to about 110 Or. Comparative example 2
In this case, no limestone was added, the oxygen concentration of the oxygen-enriched air was kept constant during the operation, and the charging rate of the gold-containing silver silicate ore was kept constant, so the temperature rose too much and reached 1850-1400.
It became 'C. In this case as well, when the temperature exceeded 1300C, slopping became severe and a large amount of blow-up material was generated even though the amount of iron in the copper converter treated at one time was reduced. In Comparative Example 3, no limestone was added, and the temperature was controlled to 1250 to 1300 t:' by adjusting the oxygen concentration of the oxygen-enriched air and the charging rate of the gold-containing silver silicate ore.

In Table 3, which shows the effects of CaO addition and temperature control on the amount of refractory corrosion in the converter, in the comparative example, no limestone was added, the temperature was the same, and the final forging temperature was 1800 t:' or higher. This is the case.

〔effect〕

As described above, according to the present invention, it is possible to dissolve gold-containing silver silicate ore in a short time without leaving any undissolved matter, thereby reducing fuel consumption, extending the life of the refractories in the reaction vessel used,
By suppressing the slopping of the metal, it is possible to reduce the number of blown-up objects, reduce the number of repeated objects, and in turn reduce handling losses of gold and silver, thereby improving productivity.

[Brief explanation of drawings]

Figure 1 shows the thickness of the millet layer formed on the upper layer of the cooling layer and the addition of limestone when gold-containing silver silicate, limestone powder, and pulverized coal are added to the copper converter furnace, melted, and then cooled. Figure 2 shows the melting time at each temperature when gold-containing silver silicate ore and pulverized coal are added to the copper converter and when limestone is added and melted. FIG. 2 is a diagram showing the state of dissolution of gold-containing silver silicate ore. Applicant: Sumitomo Metal Mining Co., Ltd. - Figure 1 3 CaO Nagisa addition rate (Time 1" Haze amount 2) Figure 2 Override CaC)

Claims (1)

[Claims] (1) In a method of processing gold-containing silver silicate ore by adding a reducing agent and gold-containing silver silicate ore to a copper converter (■) and melting it, the recovered copper absorbs gold and silver. 1200～
A method for treating gold-containing silver silicate ore, which comprises maintaining the temperature at 1300° C. and adding and dissolving a CaO-containing substance in (2) so that the CaO grade in (1) becomes 3.0% by weight or more.