RU2333039C2 - Method of extraction of ilmenite out of mine refuses - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: method includes magnetic-gravitational separation with application of the magnetic sluice, classification of the concentrate obtained, magnetic separation and drying. Classification is conducted by selecting grain class 0.5-0.1 mm, which is subject to magnetic separation by means of permanent magnet with the yield of magnetic and non-magnetic products; next non-magnetic products are enriched by electro-magnetic separation with low- and low-intensity fields.

EFFECT: ilmenite is extracted in high intensity electro-magnetic fraction.

1 dwg, 4 tbl

Description

The invention relates to the mining industry, and in particular to the field of extraction of ilmenite from tailings of ore dressing. Tails of enriched ores can include many valuable minerals, such as ilmenite, rutile, zircon, leukoxin, monazite, etc. These useful minerals are extracted based on magnetic and electrical properties, the density of individual mineral components and inclusions.

Various technological processes for the extraction of valuable components from ores are known, such as magnetic gravity separation, electrostatic separation, conditioning, followed by various reagents, firing (Cl. RF No. 2187379 C2, 08.20.2002, Cl. RF No. 2235602 C1, 10.09. 2004, p. Of the Russian Federation No. 2211091 C1, 08/27/2003, etc.). The "Method for the integrated processing of fine-grained zircon-ilmenite sands" (clause of the Russian Federation No. 2040566 C1, 07.25.95) describes in detail the existing technological processes for the extraction of ilmenite. In addition to the density separation process (WET PLANT), magnetic separation (WHIMS) and DRY MILL dry grinding, there is a firing process. The proposed technological structure eliminates the preliminary stages of WHIMS / DRY PLANT enrichment and replaces them with firing and magnetic separation using a low and medium intensity magnetic field. The "Method for the extraction of ilmenite" (p. RF No. 2094125 C1, 10.27.1997) also use firing, followed by magnetic separation of the components. Existing methods are labor intensive, environmentally unsafe and require more precise management.

The closest in essential features can be considered the "Method of processing ilmenite-titanomagnetite ores" (application No. 94041454 A1, 02.27.1997). The authors tried to propose a multi-stage technological process, including grinding, wet magnetic separation in several stages, drying and electrical separation. The disadvantage of this process was the complexity and repeatability of the steps.

The purpose of the present invention is the creation of such a technology for the extraction of ilmenite from the source material, which would combine several technological methods and would be environmentally friendly, available in ordinary conditions that do not require expensive equipment.

The problem is achieved in that the initial product (dump material) is subjected to magnetic-gravity separation using a magnetic gateway. The resulting concentrate is dried and classification is carried out with a choice of class size of 0.5-1.0 mm The selected product is subjected to magnetic separation using a permanent magnet to obtain magnetic and non-magnetic products. Then non-magnetic products are subjected to electromagnetic separation, which, in turn, is divided into fields of weak and strong tension. Due to its magnetic properties, the concentrate enriched in ilmenite is released in the highly electromagnetic fraction.

The drawing shows a flow chart of the proposed method.

The proposed method is carried out in several stages.

Stage 1 - the tails of mining enterprises, for example, gold and diamond miners, are enriched using a magnetic lock, including a flushing gutter, a hydraulic lock located under its bottom, a magnetic system that serves to create on the working surface a layer of flocculated magnetically active particles as the basis of a mineral bed and alternating in the length of the gateway polarity.

Stage 2 - the material is dried and sieve classification is carried out with a choice of fractions of 0.5-1.0 mm.

Stage 3 - carry out magnetic separation using a permanent magnet. The result is a magnetic and non-magnetic fraction.

Stage 4 - the selected non-magnetic part is subjected to electromagnetic separation with strong and weak tension fields. As a result, in the process of multistage enrichment, ilmenite is released in the highly electromagnetic fraction.

The proposed method was investigated and experimented on the example of the magnetic concentrate of diamond-free kimberlite tails of the Udachnaya pipe (TUD-1) of the Republic of Sakha (Yakutia).

The TUD-1 sample was divided at the magnetic gateway described above. As a result, the ratio of the initial mass to the mass of the fraction extracted at the magnetic gateway is 1/6 on average (Table 1).

With increasing size of the fraction, the yield of magnetic concentrate decreases, for example, the ratio of magnetic and non-magnetic components in a fraction of less than 0.2 mm is 1/6, and in fractions from 0.2 to 1.0 mm, from 1: 3 to 1: 6, and in fractions of 1-2 and 2-5 mm, this ratio grows from 1: 9 to 1:32. This can be explained by the fact that in a large fraction (more than 1-2 mm) many magnetic minerals are in intergrowth with light minerals (dolomite and calcite), and therefore easily go into a light non-magnetic fraction. Further, with the aim of a cleaner extraction of magnetite and ilmenite, small sample weights were processed on a hand-held electromagnetic separator. Magnetic, strongly electromagnetic, weakly electromagnetic, and non-electromagnetic fractions were isolated. The mineralogical composition, in particular magnetite, ilmenite, and garnet, was determined in the isolated fractions. Titanomagnetite with a small admixture of magnetic ilmenite is concentrated predominantly (more than 90% of the mass of the fraction) in the magnetic fraction, and magnetic sulfide - pyrrhotite is noted in small fractions (less than 0.1%). Ilmenite (about 90-95%), as well as garnets and pyroxenes, less often sulfides, fall into the strongly electromagnetic fraction. In the weakly electromagnetic fraction, the proportion of garnets, olivines and pyroxenes increases (up to 20-50%). In the non-electromagnetic fraction, mainly olivine, dolomite, calcite, less commonly non-magnetic ilmenite and sulfides (chalcopyrite, pyrite) remain. The ratio of minerals varies depending on the dimension of the fractions and the degree of enrichment of the samples.

Weight and percentages of these fractions are shown in the following table (table 2). In fractions of 0.2-0.5 mm of the TUD-1 sample (after the magnetic lock), the output of the magnetic and electromagnetic fractions is 60-70 wt.%.

The results of the spectral analysis of fractions (size 0.25-0.5 mm) of different magnetic susceptibilities show that the magnetic fraction is enriched in iron oxide, and the electromagnetic fraction is enriched in titanium and iron oxides (Table 3).

In the TUD-1 sample of a weakly electromagnetic fraction, the proportion of silica, alumina, and calcium oxide increases, which is caused by garnets. In the non-electromagnetic heavy fraction, the proportion of sulfur and phosphorus increases sharply, which is associated with an increase in its sulfides and apatite.

The Kamebaks-Micro microprobe analyzer was used to study the composition of oxide-ore minerals from magnetic and strong electromagnetic fractions. The main minerals are ilmenite and titanomagnetite, chromite is less common (Table 4). Ilmenites from the electromagnetic fraction differ from magnetic ilmenites in lower iron content, manganese, chromium, but high magnesianity.

T.O. the proposed method can be used in the enrichment of sands of alluvial deposits, ores, technogenic materials containing non-ferrous, rare, precious metals, and can also be used for the simultaneous separation of impurities of heavy minerals and metals from various mineral raw materials, in sizing operations, in exploration practice.

Table 1. Granulometric composition of the TUD 1 sample after separation at the magnetic gateway Fractions, mm Weight g % content The weight of the magnetic fraction, g Weight of non-magnetic fraction, g Magnetic / non-magnetic ratio 2-5 2300 7.6 70 2,230 1/32 1-2 16000 53,2 1,600 14,400 1/9 0.4-1 6000 19.9 1,550 4,450 1/3 0.3-0.4 1400 4.6 310 1,090 1/6 0.2-0.3 2000 6.7 380 1,620 1/4 <0.2 2400 8.0 350 2,050 1/6 Total 30100 100.0 4,260 25,840 1/6

Table 2. Weight and percentage ratios of the separation of the heavy fraction by magnetic susceptibility No. of samples fraction, mm Total weight, g /% Magn. fr. g /% Strong Elm. fraction, g /% Weak Elm. fraction, g /% Nonelectromage fraction, g /% TUD-1 61.70 g 19.25 g 23.45 g 6.75 g 12.25 g 0.25-0.5 mm one hundred% 31% 38% eleven% twenty% TUD-1 19.25 g 6.05 g 5.48 g 2.37 g 5.35 g 0.2-0.25 mm one hundred% 32% 28% 12% 28%

Table 3.
The results of spectral analysis of the sample TUD-1 Fraction SiO ₂ TiO ₂ FeO MgO MnO Cao Al ₂ O ₃ P ₂ O ₅ S Amount Magnetic 3.29 16.78 73.18 3.47 0.31 1.27 0.85 0,03 0.64 99.82 High electromagnetic 4.10 41.92 42.87 6.49 0.26 1.21 1.19 0,03 1,59 99.66 Weakly electromagnetic 16.50 10.58 49.95 9.48 0.46 2.65 6.38 0.04 3.35 99.39 Non-electromagnetic 14.90 0.86 47.11 14.70 0.16 2,50 2.18 0.20 16.8 99.41

Table 4 Representative analyzes of ilmenites, chromite and titanomagnetite from the TUD1 sample Sample No. No. anal. TiO ₂ FeO MgO MnO Al ₂ O ₃ Cr ₂ O ₃ Amount Ilmenites from the electromagnetic fraction TUD 1 52 46.80 42,43 7.11 0.23 0.50 1.90 98.97 54 47.34 43.84 7.67 0.20 0.46 0.98 100.49 63 47.83 41.84 7.99 0.27 0.38 1.43 99.74 57 49.69 40.01 8.89 0.21 0.50 0.36 99.66 61 50.05 39.42 8.83 0.22 0.41 0.27 99,20 62 50,43 37.65 9.24 0.21 0.56 1,03 99.12 n = 13 Min 46.80 37.65 7.11 0.16 0.38 0.27 Max. 50.79 43.84 9.24 0.31 0.56 1.90 Average 48.65 41.40 8.21 0.22 0.48 0.84 Ilmenites from the magnetic fraction TUD-1 10 45.67 43.24 7.05 0.23 0.50 2.64 99.33 mf 2 46.07 52.78 1,04 0.08 0.00 0.11 100.08 7 46.41 41.41 8.97 0.27 0.44 2,32 99.82 5 47.07 43.39 7.50 0.23 0.59 1,07 99.85 8 49.65 39.49 8.47 1.47 0.47 0.37 99.92 n = 9 Min 45.67 39.49 1.04 0.08 0.00 0.11 Max. 49.65 52.78 8.97 1.47 0.59 3.37 Average 47.18 43.33 7.10 0.38 0.43 1.37 Lame TUD1 6 0.83 36.40 5.95 0.69 3.70 52.87 100.44 Titanomagnetite TUD1 58 15.04 80.90 0.14 1.10 0.00 0.22 97.40

Claims (1)

The method of extraction of ilmenite from the tailings of ore dressing, including magnetic gravity separation using a magnetic gateway, the classification of the obtained concentrate, magnetic separation and drying, characterized in that the classification is carried out with the choice of class size 0.5-0.1 mm, which is subjected to magnetic separation using a permanent magnet to produce magnetic and non-magnetic products, after which non-magnetic products are enriched with electromagnetic separation with weak and strong fields of tension, while ilmen t silnoelektromagnitnoy isolated fractions.