Beneficiation and purification process of talc molybdenum ore

Ore nature 1

The molybdenum was mainly in molybdenite, associated magnet ore rich in talc, asbestos (ophiolite rock) and other phyllosilicate minerals. The talc and molybdenum ore are unevenly embedded in coarse and fine, mainly composed of fine particles, so the main gangue minerals affecting the separation of molybdenum are talc and a small amount of snake mosquito. The natural floatability of talc and molybdenite is very similar, and direct separation by flotation is difficult.

Table 1 Mineral composition

Table 2 Chemical composition

Ore grinding product particle size analysis 2

The particle size analysis of the grinding products, from the ore coarse grinding product particle size analysis results, the molybdenum ore distribution is higher at +0.020mm, the distribution rate is relatively low at -0.020mm, while the talc is significantly enriched at -0.020mm. In particular, the content of talc in the slime (-0.010mm) is high, so classification can be used to separate the talc.

Table 3 Grinding product analysis results

Beneficiation process determination 3

The symbiotic talc content in the molybdenum ore is 13%. Since the natural floatability of talc is very close to that of molybdenite, a large amount of talc minerals seriously affect the molybdenite flotation, and it is difficult to obtain good molybdenum by using flotation agent to inhibit talc. The ore dressing index, how to reduce the interference of talc on molybdenum ore flotation is a difficult problem in this type of ore dressing.

Talc is the lowest hardness mineral in nature. It has very low hardness compared with other minerals. It is easy to dissociate and crush in the crushing process. The talc is enriched to the fine fraction by coarse subdivision, so that the coarse fraction is not affected. Talc interference. From the results of mineral analysis, the talc in the ore is closely symbiotic with iron minerals such as magnetite. Some talc is separated by magnetic separation. The separation of talc and molybdenum is achieved by magnetic separation and coarse subdivision. The principle process flow is shown in the following figure.

Figure 1 Principle Sorting Process

Magnetic separation 4

The talc in the molybdenum mineral is closely symbiotic with magnetite and maghemite. Therefore, magnetic separation can be used to discard the influence of talc symbiotic with iron minerals on molybdenum flotation, and different magnetic field strength sorting comparison experiments.

Figure 2 Magnetic separation

Table 4 Magnetic separation test results

It can be seen from the data in Table 4 that magnetic separation can separate more than 20% of the talc from the ore into the fine mud flotation. Increasing the magnetic field strength can not only improve the recovery rate of iron, but also separate more talc minerals, but strong. The magnetic separation effect is not good, so the magnetic field strength of the grinding product can be selected in the magnetic field.

Intensity magnetic separation of iron inclusions molybdenite concentrate serious, magnetic concentrate of the magnetic separation performed after grinding, which can effectively reduce the loss of molybdenum metal, the test results shown in Table 5.

Table 5 Magnetic field magnetic separator rough selection - iron coarse concentrate re-grinding separation talc results

Fractionation 5

As a result, the majority of the talc ore comminution because of low mineral hardness distributed according to particle size analysis in the fine grinding mineral clay product, after the non-magnetic product with the magnetic separation of talc can be achieved by separating the luminance aluminum ore classification method, separating talc After that, the probability of sucking the agent on the surface of the molybdenite is improved, thereby improving the selectivity of the molybdenite.

(1) Comparison of classification effects of different grading equipment

The CKLM-55×2 medium-fine grain material slanting plate classifier and φ75mm hydrocyclone were combined as the grading separation talc equipment. The experimental design was graded with a particle size of 30 μm and the classification efficiency was 40%. The comparison test of different equipment combinations was carried out.

Figure 3 Different fractionation process

The comparison test shows that compared with the cyclone-slanting plate classifier, the grading plate classifier-cyclone combination has higher classification efficiency, and the separation product has better molybdenum flotation effect. Finally, the slant plate classifier cyclone is selected. The combination is used as a fine grading device. The test results of the crude subdivision separation molybdenum and talc are shown in Tables 6 and 7.

Table 6 Comparison of classification effects of different grading equipment combinations

Table 7 sloping plate classifier + cyclone separation and talc test results

Although the grading plate classifier and the hydrocyclone combination have a classification efficiency of only 35.71% for the -0.030mm particle size, the talc separation effect is better, and the overflow yield of the whole separation operation classifier is 16.60%, and 30.97% of the talc is separated. The amount of metal separating molybdenum is only 8.91%. From the classification of fine-grained materials and the results of particle size analysis of coarse-grained and fine-grained materials, it is known that the sloping plate classifier-cyclone combination achieves the expected fractionation effect. However, this combination has the disadvantages of large equipment footprint and small single-machine processing capacity.

(2) Cyclone-disc classification process

The talc equipment was classified and classified by the combination of GPF-320 high-speed disc classifier and φ75mm hydrocyclone. The experimental design has a graded particle size of 30 μm and a combined classification efficiency of 40%. The classification efficiency and the product classification results are shown in Table 8 and Table 9.

Table 8 Cyclone-High Speed ​​Disc Sorter Grading Effect

Table 9 Test results of fractionation of molybdenum and talc by cyclone-high speed speed disc classifier

The hydrocyclone-0.030mm classification efficiency is 35.22%, the high-speed disc sorter-0.030mm classification efficiency is 86.73%, and the -0.010mm classification efficiency is still as high as 74.51%. During the test, the equipment is not only stable but stable. The single-machine processing capacity is large, and the fine-grained material with a particle size of -0.005mm has high classification efficiency, and is an efficient fine-grain mineral classification and de-sludge equipment.

(3) Determination of fractionation process

From the comparison of the grading efficiency test results, it is known that the selection of the cyclone high-speed disc sorting machine is better for the grading equipment.

The difference in mineral composition caused by the different particle size of the material causes the hydrocyclone to have a certain separation effect on the talc. The high-speed disc classifier is used to further classify the hydrocyclone overflow, and the talc content in the coarse grit sand product is low. The molybdenum loss rate is also low, so the scheme has high efficiency in separating talc and molybdenite, and the scheme is used for the molybdenum sulfide flotation test.

Full process sorting 6

Through the above separation and classification test, the beneficiation test process flow is determined, including magnetic separation, fractionation, and molybdenum flotation. After separation of talc, the ore provides favorable conditions for greatly improving the technical index of molybdenum beneficiation. The molybdenum beneficiation test finally obtains 45.60% of high-grade molybdenum concentrate grade, 72.41% recovery rate, 10.12% of low-grade molybdenum concentrate grade, and recovery rate. 7.73%, total molybdenum recovery rate of 80.14%.

Figure 5 Magnetic separation - hydraulic classification - coarse coarse selection process

Figure 6 Fine-grained molybdenum flotation process

Figure 7 Process for selecting coarse and coarse concentrates

Conclusion 7

(1) The natural floatability of molybdenite and talc is very similar. The content of talc in ore is much higher than that of molybdenite. A large amount of talc mineral seriously interferes with molybdenum beneficiation, resulting in low grade of molybdenum concentrate and recovery of ore dressing. The single flotation process such as talc molybdenum ore flotation-separation flotation has poor ore dressing effect.

(2) Separation of talc before molybdenum ore flotation is the key to solving the utilization of this type of ore resource. It is suitable to use the magnetic separation-hydraulic grading combined process; the high-efficiency separation of talc improves the flotation environment of sulfide ore, and improves the selection. Other indicators have created favorable conditions.

(3) The selection of ore dressing equipment during separation is also one of the key technologies. The selection of equipment type and magnetic field strength during magnetic separation separation determines the separation effect. When using grading separation talc, the hydrocyclone-high speed disc classifier combines well.