Flotation study of a refractory complex polymetallic ore

A resource-rich, high grade, easy to exploit, hard to sorting complex multi-metal deposit, ore reserves of 7.816 million t, average ore grade, silver 238.92g / t, 8.34% zinc, 5.13% lead, 1.04% copper, 0.72 gold g, t, is a rare polymetallic sulphide rich deposit. The ore is rich in metals such as silver, copper, lead, zinc, arsenic and antimony . Arsenic and antimony are present in the main carrier of copper metal in the form of isomorphism. The intercalation of copper, lead and zinc minerals is quite close. Valuable metals have good responsiveness to flotation. By using “a fine-grained copper-lead-zinc sequential preferential flotation process”, independent lead concentrates and zinc concentrates are obtained, and associated metals are also comprehensively recovered in copper concentrates.

I. Mineralogy of ore processing

(1) Analysis of main chemical components

The main chemical composition analysis results are shown in Table 1. The valuable elements available are mainly zinc, copper, lead, and silver, with a small amount of beneficial associated components, and the harmful elements are arsenic and antimony.

Table 1 Analysis results of main chemical components /%

(II) Phase analysis of major minerals

The chemical phase analysis results of minerals are shown in Table 2, Table 3 and Table 4, respectively.

Table 2 Phase analysis results of copper minerals /%

Table 3 Phase analysis results of lead minerals /%

Table 4 Results of phase analysis of zinc minerals /%

Since “secondary copper sulphide” is actually mainly bismuth copper ore, it is suitable to combine “raw copper sulphide”. According to this, the vulcanization rate of the main recovered objects is about 90%, and the oxidation rate of metal minerals is higher. Low, which is conducive to the flotation of metal minerals.

(III) Analysis of the embedded relationship of major minerals

The deposit is a complex silver polymetallic deposit with many valuable components and high content. The most important metal minerals are sphalerite, galena, and beryllium ore (mainly rich in antimony-rich beryllium ore). pyrite, chalcopyrite, see a small amount of copper blue, arsenopyrite and a number of lead alum, white lead, calamine. Gangue minerals are quartz, barite and sericite, see a small amount of feldspar, kaolinite, carbonates. Although the types of metal minerals are not large, the relationship of inlays is quite complicated.

1. Beryllium ore (Cu, zn, Fe, Ag) ₁₂ (Sb, As) ₄ S ₁₃ is the most important copper mineral, and most of it is contained in silver and arsenic, so it is the ore. The most important valuable mineral in the silver, copper and harmful elemental arsenic. Scanning electron microscopy analysis showed that in addition to copper, antimony, silver, arsenic and sulfur, beryllium copper always contained a certain amount of zinc (about 9%) and iron. Chalcopyrite is a secondary copper mineral. Compared with beryllium copper, the grain size is fine. Most of the chalcopyrite and other sulfides are aggregated. Due to the complicated inter-relationship between sulfides, the grain size is fine. Chalcopyrite contact boundaries are complicated and chalcopyrite is more difficult to dissociate.

2. Galena is the most important lead mineral. It belongs to the sulfide with finer grain size. When forming coarse aggregates with other important sulfides, its particle size is relatively small among various minerals. The relationship between the ore and the beryllium copper is quite close. In addition, it is also common in the fine veins of the gangue to form fine veins.

3. The embedding characteristics of sphalerite are composed of various forms of sulfide aggregates as seen in the description of the bismuth copper ore. It is also known as a separate vein-like inlay and a fine-grained filling between the pyrite particles. And in the gangue, it is extremely fine-grained, and the size of the sphalerite of the sphalerite varies greatly, and the form of the inlay is complicated.

4. Pyrite is not the object of recycling. The sulphide has a coarser particle size and a higher content. It is closely related to other valuable minerals. It is also a gold-bearing or silver-bearing mineral. The valuable minerals are often filled along the granules. The metamorphic relationship affects the dissociation between them; the pyrite deposit, galena, and sphalerite fine inclusions are also found inside the pyrite.

Second, the determination of the flotation plan

(1) Copper concentrate rich in silver, arsenic and antimony

The most important copper mineral in the ore is beryllium copper, the secondary copper mineral is chalcopyrite, and a small amount of copper blue. Beryllium ore is the most important silver-bearing and antimony mineral (according to the silver content of 1.2% and the mineral content of about 1.8%, most of the silver is contained), other sulfides contain less silver, which is beneficial to silver and antimony. Enriched in copper concentrate. Arsenic is the main harmful impurity, mainly found in beryllium copper, and most of the arsenic will enter the copper concentrate. From the process mineralogical analysis of the above ore, it can be seen that the copper concentrate is not only rich in associated elements such as silver, arsenic and antimony, but also due to the complex intercalation relationship between copper minerals and other sulfide minerals, the copper concentrate will contain higher Lead, zinc. Obviously, the copper concentrate cannot be sold and needs to be planted separately.

(2) Dissociation degree of minerals under different grinding fineness

The dissociation degree of major valuable minerals under two different grinding conditions was measured. The results are shown in Table 5. It can be seen from Table 5 that a good dissociation of the main valuable metals can be achieved by a fine grinding.

Table 5 Determination of dissociation of valuable metal minerals under different grinding fineness /%

(3) Copper flotation test

Theoretically, a copper concentrate rich in silver, arsenic and antimony can be selected, and it can be seen by the degree of dissociation that a fine grinding can achieve better dissociation of major valuable metals, but whether it is feasible or not, flotation is required. test. Grinding fineness test was carried out with copper selective collector BK905. The test results show that with the increase of grinding fineness, the recovery rate of copper concentrate increases, and the copper concentrate recovery when the fineness of grinding is 85%-741μm. The rate is 88% at about 12% yield. Considering the grinding fineness, 85%-741μm can be used. After determining the fineness of a section of grinding, the copper selection test is carried out. The test procedure is shown in Figure 1. The test results are shown in Table 6. When the amount of collector BK905 is 32g/t, the copper recovery rate can reach more than 90%.

The copper selection conditions obtained by the adjustment test are shown in Fig. 2, and the test results are shown in Table 7.

Table 6 Copper rough selection test results /%

Table 7 Copper selection test results /%

(4) Determination of the priority flotation plan

The results of copper flotation test prove that the copper concentrate can be preferentially floated for treatment. Therefore, the other is the problem of lead-zinc separation and flotation. According to the results of the dissociation measurement, the lead-zinc separation can continue to adopt the priority scheme. .

The lead selective test was carried out with the lead selective collector BK906. The collector BK906 has good selectivity to lead at lower dosages. When the dosage is above 12g/t, the lead recovery rate can reach 87% or more. However, when the dosage is above 24g/t, the lead coarse concentrate The zinc content in the medium increased significantly, and the amount of 12g/t was selected for BK906. According to the lead selection test results, the lead concentrate grade reached 65% higher, and the recovery rate of each operation was also reasonable, but the zinc content was higher, and the lead concentrate contained zinc exceeding the standard, resulting in unqualified lead concentrate. Microscopic examination of the obtained lead concentrate shows that the main admixture in the lead concentrate is zinc mineral, and the zinc-lead continuous body is about 80%. Therefore, in order to obtain qualified lead concentrate, it is necessary. Increase lead refining and regrind.

Lead coarse concentrate regrind test. The test process is shown in Figure 3. The test results are shown in Table 8. It can be seen from the test results that the re-grinding of lead crude concentrate effectively reduces the zinc content of lead concentrate and also significantly improves the grade of lead concentrate. Considering comprehensively, it is determined that the fine grinding fineness of lead crude concentrate is 95%-45νm.

Fixing Packing Scale

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