Comprehensive Processing of Vanadium-Containing Black Shale Tailings

Abstract

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%.

Electric smelting of phosphorites with production of a ferroalloy, calcium carbide and sublimation of phosphorus

“…One of the effective and efficient methods for determining the optimal parameters for processes with a large number of output parameters is the geometric optimization method, which we have used repeatedly for various systems [25,26]. The method consists in superimposing the patterns of output parameters on top of each other; and, taking into account the accepted assumptions, the optimal values of the independent factors (in our case, the amount of coke and steel shavings) are determined, that provide the accepted levels of output parameters: αSi(alloy), αСа(alloy), СSi(alloy), ССа(СаС2), LCaC2.…”

Smelting a Zn – Pb Sulfide Ore with Magnetite and Carbon for the Production of a Silicon Alloy and Extraction of Zinc and Lead into Sublimates

“…Such raw materials increase the formation degree of zinc silicates during the roasting; they dissolve easily in sulfuric acid and form colloidal silicic acid ( H 2 SiO 3 ), which makes the subsequent thickening and filtering of the resulting solutions difficult [15]; • low degree of the raw materials' comprehensive use as 30-50% of zinc and lead and almost all non-metallic components of the ores pass into the resulting flotation tailings. (For this reason, there are additional problems associated with the processing and disposal of concentration tailings (as well as leaching tailings) of not only zinc ores but also other ores [16][17][18][19][20][21][22]). In recent years, various methods and schemes have been introduced into the lead-zinc ores concentration technology to improve its efficiency and to increase the complexity of the use of the raw materials [23][24][25][26].…”

Computer thermodynamic modeling of the producing silicon alloys from the Kentau Combined Heat and Power Plant ash

“…Traditional technological production processes are associated with the formation of industrial waste, which is placed on the territory in volumes exceeding the natural ability of the environment for self-purification and self-production. The main polluters of the natural environment are enterprises of non-ferrous metallurgy, heat power engineering, mechanical engineering and metalworking [1][2][3][4][5][6].…”