Dosmurat Aitkulov

Expansion of the raw material base of ferrous metallurgy depends to some extent on the creation of an effective technology for the complex processing of copper-magnetite ores with copper extraction. The article presents the results of studies of copper chlorination from CuS present in sulfide-magnetite ores using sodium chloride and boron trioxide. The studies were carried out in the temperature range of 500-1500 °C and a pressure of 0.1-0.001 bar by thermodynamic modeling using the HSC-10 software package based on the principle of minimum Gibbs energy. It was found that the interaction in the CuS-NaCl-B2O3-O2 system occurs with the formation of copper chlorides (Cu4Cl4, Cu3Cl3, Cu2Cl2, CuCl), sodium borates (Na2B4O6, Na2B6O10), Na2SO4, SO2(g). The temperature of the maximum (89-90%) degree of copper extraction into gaseous chlorides decreases from 1050 to 850°C with a decrease in pressure from 0.1 to 0.001 bar. It was found that the chloride sublimation of copper is accompanied by the formation of elemental copper and gaseous NaCl during the interaction of Cu3Cl3 with Na2B4O6.

This article presents the results of thermodynamic and experimental studies on the joint processing of a mixture of Shalkiya deposit zinc–lead sulfide ore and its concentration tailings in the presence of coke and magnetite. Using the HSC-6.0 software package, it was established by thermodynamic modeling that the silicon-containing products of the SiO₂ reduction in the system under consideration are FeSi, Si, Fe₃Si, Fe₅Si₃, FeSi₂, FeSi_2.33, and SiOg, which, based on the starting reduction temperature, form an increasing series: Fe₃Si (1200 °C); Fe₅Si₃, Si (1400 °C); and SiOg, FeSi₂, FeSi_2.33 (1500 °C). The smelting of the zinc–lead sulfide ore and concentration tailings mixture in the case of replacing 55% of the iron contained in the magnetite concentrate with steel shavings iron allowed us to produce FeSi45 ferrosilicon (41.9%–42.1% Si), with the extraction of 85% of the silicon in it, and sublimates containing 26.03% zinc and 13.47% lead, with the extraction of 97% of the zinc and 99% of the lead in them. In comparison with the initial ore-tailings mixture, the resulting sublimates are 11.83 times richer in zinc.

The article presents the results of thermodynamic prediction and electric smelting of Shalkiya sulfide zinc-lead-bearing ore in the presence of magnetite and coke. Using the HSC-6.0 software package, it was found that under equilibrium conditions in the presence of Fe3O4 and carbon, the reduction and formation of gaseous zinc from ZnS (according to ∆G° = 0) occurs at a temperature of 1205.7 °C, and the formation of ferroalloy at the interaction of the sulfide ore with magnetite and carbon begins at 1200 °C. About 58% of silicon is extracted into the ferroalloy at 1800–1900 °C; almost all zinc and 83–88% of lead turns into a gaseous state. Electric smelting of the sulfide ore in the presence of magnetite concentrate and coke makes it possible to obtain the FS45 grade ferrosilicon (42–43% of Si); the silicon extraction degree was 84–88%. At the same time, 97.3% of lead and 99.2% of zinc are extracted into the sublimates. The developed method for processing zinc sulfide ores allows us to increase the degree of raw materials' comprehensive use due to the extraction of not only zinc and lead, but also silicon. The technology can be used to process raw materials containing zinc, lead and silica, such as zinc ore concentration tailings.

The article presents the results of thermodynamic and experimental research on the processing of cinders from the firing of Shalkiya deposit lead-zinc ore tailings with the production of siliceous ferroalloys. Thermodynamic modeling carried out using the HSC-6.0 complex based on the Gibbs energy minimization principle showed that the interaction occur with the formation of CaSiO3, FeSiO3, MgSiO3, K2OˑSiO2, FeSi, Fe5Si3, SiC, Fe3Si, Si, SiOg, FeSi2.33, FeSi2, CaSi, Zn, Zng, Pb, Pbg; an increase in the iron amount in the system allows increasing the silicon extraction degree into the alloy at 1800°C to 76%, to reduce the silicon concentration in the alloy from 41 to 24%; FS25 grade ferrosilicon formed at 1752-1867°C in the presence of 88-100% iron, and FS45 grade ferrosilicon – at 1863-1900°C and 20-22.4% iron. Electric melting of a charge containing 63.83% calcined cinder of tailings, 19.15% coke, and 17.02% steel chips allows to obtain FS45 grade ferrosilicon (44.1-43.9% Si) with the extraction of 69.7% silicon and sublimates with the content of 32-38% zinc and lead. The results obtained allow complex processing of lead-zinc sulfide ore tailings with the extraction of not only non-ferrous metals, but also silicon in the ferroalloy.

This article examines results of the thermodynamic modeling of interaction of the briquetted tailings obtained at hydrometallurgical leaching of the vanadium-containing quartzites (black shales) with carbon and iron, determination of Si, V, Fe, C equilibrium distribution and optimal conditions for the formation of various grades of ferrosilicon, as well as the electric melting to produce silicon alloys. The research techniques were the method of thermodynamic modeling using the HSC-6.0 software package (Outokumpu), the second-order rotatable designs (Box-Hunter plans) and electrofusion in an arc furnace. It was established that an increase in the amount of iron from 11 to 39% makes it possible to increase the extraction degree of silicon into an alloy up to 72–73% in the temperature of 1800–2000 °C, in the process the silicon concentration in the alloy decreases from 57–65.7 to 40.5–40.9%; FS45-grade ferrosilicon at the extraction degree of silicon in the alloy of 70–72.6% can be formed in the temperature of 1750–2000 °C in the presence of 29–39% Fe, FS50 ferrosilicon is formed at 25.5–35.0% Fe and 1870–2000 °C, and FS65 ferrosilicon – in the temperature of 1895–2000 °C in the presence of 11–12.7% Fe. The FS45-grade ferrosilicon was formed during electric smelting of a charge containing 57% of the briquettes, 21% of coke, 22% of steel chips, and the FS50-grade ferrosilicon – using a charge consisting of 61% of the briquettes, 22% of coke and 17% of steel chips; the silicon extraction degree into the alloys is 73–79%.

The article presents the research results on the electrothermal production of a ferroalloy from an amorphous sedimentary rock tripoli. The studies were carried out by electric melting in a single-electrode arc furnace using the second-order rotatable experiment planning (Box-Hunter plan). The influence of the amount of coke and steel chips on the degree of extraction of silicon into the alloy and the content of silicon in it is determined. It was found that silicon from tripoli to ferroalloy passes by 49-90.6%, and the silicon content in the alloy is 28-48%. Ferrosilicon grade FS25 (23.0-29% Si) is formed in the presence of 30-33.6% coke and 40.6-45.0% steel chips, grade FS45 (41-46.6% Si) with 32.1-40.9% coke and 26.2-37.0% steel chips. The maximum degree of silicon extraction (90.0-90.3%) in FS45 grade ferrosilicon (42.6-43.5% Si) is observed in a small coke range (36.0-37.3%) and steel chips (33.0-35.2%). Using tripoli instead of quartzite in the charge makes it possible to reduce the duration of the process by 1.2 times.

The article presents the results of studies on the influence of time, the amount of steel shavings and coke on the electric melting of ferrosilicon manganese dusts to obtain a ferroalloy. The research was carried out by the method of rotational planning of the second order (Box-Hunter plans) and by electric smelting of dust in laboratory ore-thermal arc furnace. Dust from the production of ferromanganese by LLP Taraz Metallurgical Plant, coke and steel shavings were used during the research. It was determined that to achieve αSi≥70%the process must be carried out in the presence of 25% coke and 8.1-9% steel shavings from the mass of dust for 55.8-60 minutes, to achieve αMn in an alloy of 80-85% the process must be carried out in the presence of 25% coke, 5.7-9.0% steel shavings for 41.2-54.4 minutes. When melting the charge containing 75.2% of dust, 18.8% of coke, 6% of steel shavings, within 60 minutes the weight of the ferroalloy was 258 g (38.8% of the weight of the charge or 51.6% of the weight of dust). The degree of extraction of manganese into the alloy was 82.3%, silicon - 66.1%. The resulting ferroalloy belongs to ferrosilicon manganese of the FeMnSi12 grade.

Modern production of non-ferrous metals is imperfect due to the loss of rock mass and metal in the technological chain ore mining to metal production. Processing of zinc oxide and oxidized copper ores by hydrometallurgical, pyrometallurgical and flotation methods is associated with formation of...