Engineering Journal of Satbayev University

Study of the possibilities of obtaining a complex alloy using high-ash coals by thermodynamic modeling using a computer program

2023-05-26T10:43:00+00:00

The content of the leading elements in the technical composition of high-ash coals on the territory of Kazakhstan makes it possible to obtain a complex alloy. In accordance with this, a comprehensive study of the possibilities of obtaining an Aluminium-chromium-silicon alloy, which can be a complex deoxidizer and reducing agent, is among the topical issues. The article presents the results of a study of the thermodynamic-diagram analysis of the Cr-Si-Al-C multicomponent system, where, on the basis of thermodynamic data, the boundary ternary systems of the basic four-component Cr-Si-Al-C system are constructed. As a result, the components of the condensed phases of a multicomponent system were determined. Descriptions are given for each of the defined phases, with the help of which it is possible to create an accurate model of the general system of compositions of chromium-containing melts with the calculation of their normative phase compositions. Triangles of the Cr-Si-Al-C system have been established, modulating the compositions of the resulting compositions of metal products during the smelting of the aluminosilicochrome alloy using high-ash coals. As a result of modeling, the main components of the phase of three-component systems Аl-Si-С, Аl-Cr-Si, were revealed. Volumes and color integrals indicating condensed and gaseous phases are determined. The technology of obtaining silicon-aluminum alloys is based on the reduction of oxides from the ash of high-ash coal with its own carbon in ore-thermal furnaces.

Computer thermodynamic modeling of obtaining ferroalloys from a mixture of leaching tailings of oxidized copper ores

2023-06-20T21:22:05+00:00

The article presents the results of computer thermodynamic modeling and experiments on the production of ferroalloys of the production of ferroalloys from a mixture of tailings for sulfuric acid leaching of oxidized copper ores from the Almaly, Ayak-Kodzhan, Aktogay, Kounrad, Shatyrkol deposits, containing (%): 65.2SiO₂; 14.2Al₂O₃; 7.4Fe₂O₃; 2.4K₂O; 2.7Na₂O; 6.6CаO; 2.8MgO; 0.2CuO. The simulations were carried out using the HSC-6.0 software package based on the Gibbs minimum energy principle, as well as the research planning method using a rotatable second-order plan (the Box-Hunter plan). Experiments on melting a mixture of tailings were carried out on the Tamma furnace in isothermal mode. The influence of temperature and the amount of carbon on the equilibrium degree of distribution of silicon, aluminum and the concentration of these metals in the alloy was determined. Based on the results obtained, it was found that the equilibrium interaction of a mixture of heap leaching tailings of copper ores with carbon and iron occurs with the formation of FeSi, FeSi₂, FeSi₂_.33, Fe₅Si₃, FeSi₂_.43, Fe₃Si, Si, SiO₂, Al, SiC, CaSiO₃, Al₂SiO₅, MgSiO₃, K₂SiO₃, Na₂SiO₃, Cu, CO. An increase in iron from 30 to 50% of the mass of the mixture of leaching tailings and temperatures from 1600 to 2000ºС increases the degree of extraction into the silicon alloy to 83.2%, and reduces the concentration of silicon in it from 40-41.41% (at 1800ºC) to 30-31%, aluminum at 2100ºС from 8.3% to 5.5%. Ferrosilicon of the FeSi₄₅ brand with the extraction of 74-81.9% Si from it is formed at 1780-1910ºС, 30% iron and 34% carbon, and the FeSi₂₅ brand with the extraction of 70-76% Si into it is formed in the temperature range of 1660-1730ºС in the presence of 43.5-50% iron. Determines the influence of temperature 1000-2100ºС and iron. To achieve high (≥80%) silicon in the alloy, a temperature of at least 1800ºС and an 80-minute duration of the process are required.

Production of gallium by electrolysis with the application of non-stationary currents

2023-07-10T07:06:28+00:00

Currently, the problem of sustainable increase in the production of gallium metal to ensure its use in high-tech areas - power semiconductor electronics, energy-saving LEDs, etc. is very urgent. In world practice, electrolysis on a mercury cathode or cementation with sodium amalgam was used to extract gallium from alkaline solutions. However, this technology is not currently used due to the high toxicity of mercury. Cementation and electrocarburization on aluminum galley are widely used for purified solutions. A promising method for obtaining gallium metal from alkaline solutions is electrolysis on a solid rotating gallium cathode, the surface of which is constantly renewed with liquid gallium. To increase the efficiency of electrolysis, studies of the process of gallium electroreduction with the application of non-stationary (pulsating and reversing) currents were carried out. The use of non-stationary currents makes it possible to increase gallium extraction by 8.4-10.4% and reduce electricity consumption by 62-68 kWh/kg Ga. The positive effect of the use of non-stationary currents can be explained by the fact that periodic switching off the current or reversing the electrodes in the found optimal modes leads to a periodic change in the surface tension of the gallium cathode, as a result of which the gallium surface and the adjacаent electrolyte layer pulsate, the thickness of the diffusion layer decreases and conditions for the separation of adsorbed gas bubbles are improved. This accelerates the diffusion of gallate ions from the bulk of the solution into the near-cathode layer. The use of non-stationary currents makes it possible to dissolve the gallium oxide film on the cathode surface, i.e. depassurate the electrode surface.

Investigation of plumbum-containing slags and ways for their reclaiming

2023-10-18T14:17:32+00:00

The paper deals with analysis and findings of investigation of technogenic plumbum-zinc slag residuals that involve a great deal of poisonous compounds such as cadmium, osmium, plumbum, zinc, hazardous origins of environmental contamination. In connection with the outdoor storing of slags, an excess of the plumbum critical concentration was derived. Technogenic slag residuals’ reclamation is crucial for minimizing the detrimental effect on health and safety, improving the region’s ecological setting. At that, slags are high-value crude materials involving rare-earth and non-ferrous metal compunds. The paper demonstrates the findings of laboratory tests of slags to specify the quantitative and qualitative composition of high-value components in the plumbum residuals, the ability of their subsequent treatment and reclamation. The heavy slag fraction material was investigated on JEOL IXA-8230 Electron Probe microanalyzer. The running slag sample’s X-ray diffraction analysis was carried out on DRON-4 diffractometer with graphite monochromator, Cu radiation. Heavy fractions were separated from the samples, artifactural polished microsections (briquets) were made. The polished microsections were investigated in index-matching fluids and under LEICA DM 2500P microscope. The findings identified that plumbum slags involve a considerable body of non-ferrous metal compounds, which allow to make the reclamation of poisonous plumbum residuals functional and cost-effective.

Selection of technological equipment for complex processing of dross

2023-10-16T06:50:16+00:00

The article analyses methods of dross processing with obtaining marketable products. In recent years, along with pyrometallurgical methods, hydrometallurgical methods are beginning to develop. The authors present a new waste-free technology for processing zinc-plating waste aimed at obtaining marketable products. In the work the technological scheme of new, combined, waste-free technology of processing of zinc smelting waste with obtaining of marketable products is constructed. Technological calculations on dross processing for specific productivity of 100 tonnes per day are made, recommendations on design of the enlarged installation and on operation of the technology are given. Technological calculations were carried out using a specially developed program that considers the optimum parameters and modes of technology. This allows the authors to obtain accurate data and estimates of the dross processing process and optimize the operation of the plant. The use of the developed technology of complex dross processing will allow to stimulate the development of zinc production in the republic due to involvement of dross in processing as an additional source of raw materials. Utilization of dross with obtaining of marketable products with high added value will allow to release considerable areas of land occupied by it. Overall, the paper emphasises the potential of the new technology to address the problems of dross processing, stimulate the growth of the zinc industry and reduce the environmental impact of dross accumulation.

Features of the geological structure of the Kogodai VMS deposit in the Kurchum block

2023-09-26T08:57:01+00:00

The article considers the geological structure of Kogodai copper massive sulfide deposit in the Kurchum block, which is an integral part of the Irtysh shear zone. It is shown that the geological structure of the site involves feldspar quartz-mica and amphibole-feldspar-mica crystalline schists, gneisses with frequent horizons of amphibolites. Mineralized zones confined to the contact of amphibolite bodies with gneisses on terrigenous rocks are noted, granitoids in different phases of intrusion including dikes and various granite and quartz porphyries are also considered. The spatial contiguity of geological structures of different ages and compositions subject to intense metamorphic transformations is emphasized. This article presents the features of the copper massive sulfide deposit, the composition of the ores and the connection with the geological and structural-tectonic factors that contributed to its formation.

The influence of hydrological conditions on the formation of exploitable reserves of underground water deposits in Northern Kazakhstan

2023-11-24T13:05:52+00:00

Groundwater is an important source of water supply in the regions of Northern Kazakhstan. The formation and management of exploitable groundwater reserves in a given region are closely related to hydrological conditions. This article analyzes the influence of climatic factors, hydrogeological features and human activity on the formation of operational groundwater reserves in Northern Kazakhstan. The study is based on an analysis of the results of prospecting and assessment work and data from the pilot operation of the Alekseevskoye groundwater deposit in the Akmola region of the Republic of Kazakhstan.