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The article considers the results of studying the thermodynamic computer modeling of the interaction of phosphorite (Karatau basin, Kazakhstan) with carbon and coke performed using the HSC-10 software package and electric smelting of the phosphorite with coke and steel shavings in an arc furnace. The modeling allowed us to determine the equilibrium extraction degrees of phosphorus into gas (P2, P4), silicon into ferroalloy in the form of iron silicides (FeSi2, FeSi, Fe3Si, Fe5Si3, Si) and calcium into CaC2. At temperatures above 1500 °C, regardless of the amount of iron, the extraction degree of phosphorus into gas is more 99%. The resulting ferroalloy contains 21.2-23.8% of Si, 1.6-2.8% of Al; the calcium carbide has a capacity of 288-325 dm³/kg. The extraction degree of silicon into the alloy was 89.8%, calcium in CaC2 - 72.5%, phosphorus into gas - 99.4%. The ferroalloy, formed at the electric smelting of the Chulaktau phosphorite together with coke and steel shavings and containing 24.9-29.8% of Si, is FS25 grade ferrosilicon, and the formed calcium carbide has a capacity of 278-290 dm³/kg and belongs to the third and second grades. The developed technology makes it possible to increase the degree of phosphorites' comprehensive use two times (up to 87.5%). [ABSTRACT FROM AUTHOR]

The modernization of the reactor equipment for the industrial process of sulfuric acid alkylation of isobutane with olefins is considered. Improvement of the "classical" technology for the production of high-octane gasoline is ensured by the use of small-sized reaction apparatuses of a diffuser–confuser design, which contributes to the optimization of the hydrodynamic regime in the reaction space. A theoretical analysis of the flow of this emulsion process with the rationale for the proposed structural design of the contactor apparatus is given. The conducted industrial tests of the technology are described, which confirmed the high efficiency of the applied design in comparison with the functioning industrial processes of sulfuric acid alkylation, in terms of reducing energy costs, and optimizing consumption indicators for the components of the raw materials and the catalysts. [ABSTRACT FROM AUTHOR]

This article is devoted to basalt reprocessing together with magnetite concentrate in order to obtain ferrous alloy and calcium carbide. The studies have been based on thermodynamic simulation and electric smelting in arc furnace. The thermodynamic simulation has been performed using HSC-5.1 software based on the principle of minimum Gibbs energy. The blend was smelted in arc furnaces. On the basis of the obtained results of combined processing of basalt, it has been established that under equilibrium conditions, the increase in carbon content from 36 to 42 wt % of basalt and concentrate mixture makes it possible to increase the aluminum extraction into the alloy up to 81.4%, calcium into calcium carbide - up to 51.4%, and silicon into the alloy - up to 78.5%. Increase in the amount of lime to 32% allows to increase the content of calcium carbide to 278 dm3/kg. Electric smelting of the blend under laboratory conditions in the presence of 17- 32% of lime makes it possible to extract ferrous alloy containing 69.5-72.8% of silicon, 69.1-70.2% of aluminum, and to obtain ferrous alloy containing 49-53% of SSi and Al and calcium carbide in the amount of 233-278 dm3/kg. During large-scale laboratory smelting of blend comprised of basalt (38.5%), magnetite concentrate (13.4%), lime (15.4%), and coke fines (32.7%), the ferrous alloy has been produced containing 48-53% of SSi and Al, calcium carbide in amount of 240-260 dm3/kg. Extraction of Si and Al into the alloy was 70.4 and 68.6%, respectively; Ca into carbide - 60.3%; Zn and Pb into sublimates - 99.6 and 92.8%, respectively. [ABSTRACT FROM AUTHOR]

The article presents the results of studies on the use of the high-silicon phosphorites (51,8 % of Ca3(PO4)2, 25,6 % of SiO2) for the co-production of ferrosilicon, calcium carbide and gaseous phosphorus. The studies included the electric smelting a charge in an arc furnace and using the second-order rotatable designs. The conditions of producing FeSi45 ferrosilicon (51,2-54,2 % of coke, 12,5-18,4 % of steel shavings) and FeSi25 ferrosilicon (53-58 % of coke, 39,7- 40 % of steel shavings) with extraction of 65-67,8 % of silicon into the alloy were determined. The second product of the process is technical calcium carbide with a capacity of 129-167 l/kg, in which from 44,8 to 64,1 % of calcium is extracted. At least 99,3 % of phosphorus during the electric smelting is sublimated. [ABSTRACT FROM AUTHOR]

The presented paper contains the research results of extraction of the reduced silicon from the corundum matrix by means of different methods. The research has been performed with use of several methods: separation in a heavy suspension, sedimentation in high-viscous mediums and electrostatic separation. The results obtained at the studying of separation of the matrix (corundum) and the silicon produced from quartz glass and aluminium powder allowed to draw following conclusions: separation in an alcohol-bromoform medium allows to take no more than 16% of silicon; in the process the silicon concentration in the product makes 40-42%; at use of a water-glycerine mixture the silicon content in the product makes 39-49%, and the extraction degree of Si in it is no more than 32%; electrostatic separation allows to extract into the product 83-89% of Si; in this case the product contains 88-92% of silicon; application of iodine transport (the "inverted crucible" technique) allows to produce high-pure (99%) silicon at the actual extraction of 72,5 % and predicted one - 88,7%; for obtaining purer silicon (99,9999% of Si) we recommend to use vacuum purification. [ABSTRACT FROM AUTHOR]