Industrial Ore Research Articles

IMPROVEMENT OF METHODS FOR DECOMPOSING MOLYBDENUM IN INDUSTRIAL PRODUCTS

The study of methods for extracting molybdenum into solutions from industrial ores and concentrates is an important task in the mining and metallurgical industry. Molybdenum (Mo) is used in the production of steel, alloys, electrode materials, and catalysts. The purpose of this work is to increase the efficiency of decomposition of molybdenum-containing materials, reduce production and processing costs, and minimize environmental impact. The tasks include the development of new chemical and metallurgical processes for processing various ores and concentrates, involving their decomposition and the extraction of molybdenum into a solution. Methodology. The study used microwave autoclave decomposition methods and chemical decomposition (acidic and fusion). The composition of the solution was determined using the atomic absorption method. The novelty of the research lies in the use of isolated microwave autoclave decomposition, which combines high efficiency and environmental safety. Results and discussion. The study compared the results obtained by the method of acidic decomposition and fusion in an open system with those from microwave autoclave decomposition in a closed system. Each method has its own advantages and disadvantages. The results of acidic and autoclave decompositions were similar to each other, while the results of fusion showed increased metal contents. The values of decomposition methods for standard copper and molybdenum concentrates showed results of 0.1-2.4%, respectively. The values of acidic (0.8%; 0.98%) and autoclave (0.9%; 1.04%) decompositions for samples from Chirchik and Stepnogorsk concentrates yielded similar results. Conclusion. The results of the decomposition methods of the materials do not differ significantly from each other from a production or industrial point of view. The analysis results can be applied in practice or used as reference values for scientific research.

Establishing a Mining Group of Deposit and an Exploration Grid Pattern for Uranium Ore Intercalated in Sandstone at Pa Lua - Pa Rong Area, Nong Son Basin

This research shows the results of establishing a mine group and a uranium ore exploration network in Nong Son depression sandstone, Quang Nam province based on the results of exploration of uranium ore bodies in the Pa Lua - Pa Rong area. Some main findings include: i) The uranium content in most industrial ore bodies can be attributed to a lognormal distribution function. The ore bodies (two main ore bodies are referred to as TQ1 and TQ2) have an average uranium concentration from 0,032% to 0,054% U3O8 with high variations (with the amount of variation in content (Vc) greater than 100%). The average thickness of the ore bodies is from 2,30 meters to 2,35 meters. The thickness variation coefficient (Vm) varies from 89,4% to 100,3%, indicating the unstable to very unstable type of ore body; and ii) Uranium mines in sandstones of the Pa Lua - Pa Rong type, Nong Son basin mainly belong to exploration mine group III. The most reasonable exploration approach is to use a parallel and fan-shaped network. To calculate the reserves, the distance between drilling routes is set at 50 to 60 meters. To determine the road and pavement, wet set the drilling routes to be 25 to 30 meters apart from each other. This exploration network can be applied to other sandstone mines in the Nong Son basin with similar characteristics to the Pa Lua - Pa Rong mine.
 
 

Scientific and technical problems of transition from open pit to combined technologies for raw materials mining

In Kryvyi Rih iron ore basin, long-term and intensive mining of deposits applying open pit methods have resulted in significant areas disturbed by open pits, dumps and tailings storage facilities. Hundreds of thousands of hectares of fertile arable land are already unsuitable for agriculture and sometimes for living. Thousands of tonnes of dust from dumps and tailing ponds deteriorate the surrounding nature every year and pollute the atmosphere in mining basins. Industrial ore breaking in open pits using bulk blasting causes emissions of a significant amount of harmful dust and carcinogenic substances. The environmental situation in open pit mining areas is often close to critical. In addition, bulk blasting forms a seismic wave, which in some cases destruct civil buildings and industrial facilities. The article proposes ways of gradual transition from mining mineral deposits by open pit methods to environmentally friendly technologies of open pit-underground and underground mining. It is established that such transition is a forced and at the same time choiceless way of developing mining areas, in particular Kryvyi Rih iron ore basin. The paper notes that the main problems of this transition include geomechanical stabilization of the rock massif during construction of underground mines in areas of possible impacts of open pit fields. The paper develops the fundamental study of the problems of controlling the stress-strain state of the massif during transition from the open pit to combined technology of deposit mining. Technologies of combined mining that involve formation of a transition belt with backfilling the worked-out space with compound mixtures are studied as well. It is proved that development of theoretical foundations for controlling the stress-strain state of the massif during transition from the open-pit to combined technology of deposit mining, study and design of technological solutions that contribute to transition to open pit-underground and underground mining, is an urgent scientific, technical and practical problem of great importance.

Quantitative evaluation of collector flotation performance I: The creation of a flotation index based on mineral recovery

Collectors are crucial for successful flotation, and their performance evaluation is one of the most important steps in their development process. It is urgent to create new evaluation indices/methods because the existing indices/methods are not ideal in terms of standardization and universality. Collector flotation performance is conventionally evaluated using two parameters, i.e., collecting ability and selectivity. Thus, a two-dimensional evaluation space exists. Through the creation and normalization of a flotation index (FI), based solely upon mineral recovery, this evaluation space may be reduced to one-dimension, in the range of 0 ∼ 1 and verified mathematically. In the construction of FI, the relative recovery (Rr; collector-induced recovery) of the target mineral replaces the absolute recovery (R; used for the existing indices/methods), quantifying actual collecting ability and excluding the adverse effects of variable minerals’ natural or inherent floatability (Rn). Moreover, selectivity is quantified by the recovery gap (ΔR) between the target and gangue minerals. Compared with separation efficiency (SE; a conventional evaluation index), FI fills a gap in collector performance evaluation for single minerals by a convenient process. Additionally, FI can qualitatively/semi-quantitatively evaluate collector flotation performance for mineral mixtures and industrial ores based on the evaluation results for single minerals, reducing laboratory costs. It should be noted that if FI is directly used to calculate collector flotation performance for mineral mixtures and industrial ores, grade analysis is indispensable. The normalized and dimensionless FI is more universal, providing a standardized comparison of collector flotation performance for different flotation systems, different minerals/ores or the same mineral/ore from different mining areas. As the scoring function of flotation performance, FI is the basis for the subsequent construction of a standardized method to comprehensively and quantitatively predict collector flotation performance in combination with quantitative structure–activity relationship (QSAR), machine learning (ML) and Quantum chemistry (QC).

High-Precision and Rapid In Situ Ore Element Detection Based on Laser-Induced Breakdown Spectroscopy

In most cases, in situ online composition detection is highly desirable for the iron and steel industry. High-precision prediction of the iron content of an iron ore is quite difficult due to the complexity of ore composition. Herein, an online composition analysis system based on laser-induced breakdown spectroscopy (LIBS) is built up for real-time Fe concentration determination. Subsequently, using the support vector machine (SVM) combined with multivariate partial least-squares regression (PLSR) to establish a linear relationship between the spectral data and typical element content, the iron content in the standard ore tablet is used as the true value to train the model, and the iron content in the raw ore block is predicted, with an error of 1.6%. By studying the elemental distribution content of the raw ore with repeated laser ablation, it is found that the internal element content of the ore changes at different depths from the surface, and the element content quickly stabilizes. The results demonstrate that the method can accurately and effectively predict iron content online, allowing the application of online detection of industrial ore composition.

INCREASING OF THE MINERAL AND RAW-MATERIAL BASE OF UKRAINE WITH NEW OBJECTS OF TITANIUM ORES

Ukraine has the largest reserves of titanium in Europe. Over the past decades, in the country has also established and estimated significant amounts of promising resources of titanium ores. Now the resource potential is several times the reserves of industrial ores. The mineral base of titanium ores is represented by magmatic in bedrocks, residual and alluvial deposits. New objects with estimated resources are located within the western part of the Ukrainian Shield. These are the of titanium ores with apatite in mafic rocks and their crust of weathering. In the northeast of the Ukrainian Shield there are titanium deposits with zirconium. In the central part also found magmatic, residual and alluvial deposits. And, finally, prospective resources of complex vanadium-containing titanomagnetite ores of the central part of the Pokrovo-Kyriiv structure in the junction zone of Donbas and the Azov megablock were evaluated. In order to provide potential investors with information on the existence of investment objects with certain resources and geological and economic evaluation, the State Service of geology and subsoil of Ukraine launched an investment atlas of the subsoil user. In order to supplement the investment atlas with objective data on the resource potential of solid minerals of the country, it is necessary to create an information base of promising and forecasted resources of metallic and non-metallic minerals and, first of all, those related to strategic mineral raw materials. In connection with the rapidly growing demand for titanium-zirconium products in the world, there was a need to involve in the development of new objects of titanium ores with favorable economic indicators. The accumulated material on the state of the resource potential of titanium and titanium-zirconium ores provides an opportunity to supplement new content of investment information for subsurface user.

BACTERIAL LEACHING OF BALANCED ORES OF ALBITITE DEPOSITS OF THE UKRAINIAN SHIELD

Prospects for increasing the raw materials resources of uranium ore deposits of the albite formation of the Ingul megablock of the Ukrainian Shield and the possibility of reducing the impact of harmful waste due to the method of bacterial leaching of metals were considered. Mineral-forming systems of uranium-bearing albitites of the Ukrainian Shield have always been considered as monoelement, exclusively uranium objects. However, their out-of-balance ores and tailings contain elevated, up to industrial, concentrations of other metals, which, under conditions of hypergenic processes, pose a potential threat of environmental pollution. In order to determine the possibility of expanding raw materials resources of albite deposits of the Ukrainian Shield due to the use of the method of bacterial leaching of metals, the composition of industrial ores and host rocks was considered. In particular, our data from their mineralogical and geochemical research showed that uranium and five of its companion elements: thorium, vanadium, beryllium, zirconium and lead reach industrial content. At the same time, cobalt, nickel and zinc are characterized by an increased content close to the minimum industrial values. The most promising for bacterial leaching are rocks that contain sulfides. The rocks of the uranium ore albitite formation contain sulfur-containing compounds and, in particular, pyrite, as well as bi- and trivalent iron. We found the highest content of sulfides in albitized rocks (up to 0.82%), ore-free albitites (up to 0.81%), low-ore albitites (up to 0.61%), that is, in rocks accumulated in industrial waste. It is assumed that the use of bacterial leaching methods with the participation of chemolithotrophic microorganisms can be promising for the processing of off-balance ores and will contribute to the expansion of the raw material base of albite deposits of the Ukrainian Shield, due not only to uranium, but also to nickel, cobalt and zinc.

The potential of the Russian raw material base of zirconium for production of ZrO2-based refractory materials

The article is devoted to solving the problem of providing Russian manufacturers of refractory ceramic materials based on ZrO2 with domestic zirconium raw materials. The relevance of the study lies in the need to expand the Russian production of zircon refractories in order to ensure the technological integrity of Russia and the provision of consumable components in steelmaking. Zircon raw materials for the production of refractories belong to the group of metals that are mostly imported from abroad for domestic use. Deposits, production and logistics of refractory clays and kaolin, quartzite and magnesite in Russia are sufficiently developed and allow providing refractories manufacturers with domestic raw materials. The purpose of the article is to analyze the potential of the domestic raw material base of zirconium compounds for the production of refractory materials and products based on them. The technology and experience in the production of heat-resistant structures in ceramics based on ZrO2 at ONPP «Tekhnologiya» named after A. G. Romashin for the aviation, aerospace industry, nuclear energy using domestic raw materials of zirconium dioxide. It is determined that the consumption of ZrO2 in Russia is about 10 thousand tons per year, which is mainly represented by imported zircon concentrate (more than 90 %) and in a small amount by domestic baddeleyite concentrate. Based on the analysis of mineral resources, it has been established that the Russian raw material base of zirconium is sufficient to meet the needs of Russian enterprises in zirconium raw materials, but its development is hindered by the deep hard-to-reach occurrence of the metal, the lack of industrial ore dressing technology and the complexity of further processing of the resulting concentrates. With the planned indicators for the development of the Tuganskoye deposit, by 2026, a complete transition of the Russian industry to domestic zircon raw materials is possible, and if the enterprise reaches full capacity by 2030, the production volume of the concentrate will be four times higher than the current volume of consumption, which will allow organizing its export.

Geochemistry of Mudstones/Silty Mudstones from the Qigequan Formation and Shizigou Formation in Yuejin-II Area, Southwestern Area of the Qaidam Basin: Implications for Sedimentary Environment and Sandstone-Type Uranium Mineralization

The Qaidam Basin has been the focus of sandstone-type uranium prospecting since the 1950s. In recent years, relying on the uranium geological survey project supported by the China Geological Survey, and the cooperation with the Qinhai oil company, drilling work at the Yuejin-II area in this basin has achieved breakthroughs on industrial-level sandstone-type uranium exploration. In this study, we present major, trace and REE geochemical analysis of the Qigequan Formation and the Shizigou Formation mudstones/silty mudstones collected from an industrial uranium ore drillholes in the Yuejin-II area. The Shizigou and Qigequan Formations exhibit signatures of non-intense alteration, low rock maturity and proximal provenance. The overall arid paleoclimatic conditions controlled the sedimentation of large volume of uranium rich materials. The period of relative humidity prompted the sedimentation of reduced agents. Aided by the neotectonic-induced slopes and tectonic windows, oxygenated fluids migrated along permeable layers and extracted the hexavalent uranium, transported in the form of uranyl ion (UO22+). When the oxygen–uranium-rich fluids finally infiltrated into the reductive sand body, the hexavalent uranium was reduced to tetravalent uranium and deposited in the form of uranium compounds. Large-scale and centrally distributed reductive sand bodies provided favorable ore storage space for the sandstone-type uranium mineralization in the Yuejin-II area.

NEW HORIZONS PROCESSING OF TECHNOGENIC WASTE OF THE COPPER INDUSTRY

At the present time, in the mining and metallurgical industry, there are trends in the processing of man-made waste that have accumulated over the course of many years. Since the world's reserves of ore deposits with a high initial content of non-ferrous metals and easily processed ores are currently practically depleted. This is due to a decrease in the volume of processing of conditioned ores and the involvement in the development of industrial waste, refractory ores and off-balance from low-grade dumps. High prices for metals on the world market create a favorable environment for the development of technologies for the extraction of precious metals involving the processing of mineral resources of technogenic origin. The work studies the mineralogical composition of industrial waste from the copper industry in the conditions of JSC "Almalyk MMC", determined the effectiveness of methods for the selective extraction of platinoids and paid attention to the methods of dissolution, reduction of platinum metals and methods of their purification from various impurities. Based on the study of this topic and the analysis of the results of the research, the authors proposed an optimal technology and complex methods for extracting platinum, palladium and rhodium from industrial waste using selective methods suitable for each metal separately using hydrometallurgy and pyrometallurgy. Hydrometallurgical methods have been developed for the purification of palladium, platinum and rhodium with treatment, respectively, with formic, citric and nitric acids. As a result of the developed technologies, the possibility of complex extraction of platinum group metals from industrial waste has been achieved. In this case, the end-to-end extraction of all platinoids is over 80%.

Evaluating the reliability of the exploration and calculating Uranium reserves of the Binh Duong Deposit, Cao Bang province

This paper presents new results about evaluating the exploration's reliability and Uranium reserve calculation of the Binh Duong deposit, Cao Bang province, by using the multiple math statistical and geostatistics methods. The results indicte: - The Uranium ore bodies in the Binh Duong deposit are lenticular-shaped, complex morphology and structure. They belong to the small-scale type, with complex changes. - The Uranium contents of industrial ore bodies calculated by the ore thickness’ weighted average method are comparable to those estimated by the adjacent bulk method. However, these values are systematically lower than the mean values. - The crucial factor in the reliability of the exploration and calculation for reserves in the Binh Duong Uranium deposit are the ore bodies’ thickness and random error in sample analysis. - The error in calculating uranium reserves in the case of taking into account the efficiency of using the internally and externally extrapolating boundaries of the ore body are larger than the case without paying attention to this efficiency. - The exploration network has been carried out being within 40m along the strike and 20÷40 m along the slope, enough basis to calculate reserves at level 122; however, out of this network only responds to the requirement of calculating resource at level 333.

Curvature flows, scaling laws and the geometry of attrition under impacts

Impact induced attrition processes are, beyond being essential models of industrial ore processing, broadly regarded as the key to decipher the provenance of sedimentary particles. Here we establish the first link between microscopic, particle-based models and the mean field theory for these processes. Based on realistic computer simulations of particle-wall collision sequences we first identify the well-known damage and fragmentation energy phases, then we show that the former is split into the abrasion phase with infinite sample lifetime (analogous to Sternberg’s Law) at finite asymptotic mass and the cleavage phase with finite sample lifetime, decreasing as a power law of the impact velocity (analogous to Basquin’s Law). This splitting establishes the link between mean field models (curvature-driven partial differential equations) and particle-based models: only in the abrasion phase does shape evolution emerging in the latter reproduce with startling accuracy the spatio-temporal patterns (two geometric phases) predicted by the former.

Peculiar features of correlation between petrophysical signatures of rocks and distribution of geophysical heterogeneities in the Monchegorsk ore area (Kola Peninsula, northeastern Baltic Shield)

The current article presents stratified data on physical properties of rocks and ores from the Monchegorsk ore area (Kola region). The constructed petrodensity and petromagnetic maps reflect peculiar features of changes in petrophysical parameters of both Paleoproterozoic intrusive rocks and host rocks at the Archean basement of the area. To assess the complementarity degree of physical properties of the rocks and geophysical fields, we additionally analyzed the structure of geophysical anomalies (Δg, ΔZ) in the study area. It allowed constructing a distribution scheme for geophysical heterogeneity in the area and assessing their nature.
 The conducted studies showed that nickel-bearing and potentially nickel-bearing intrusions in the Monchegorsk ore area were highly dense, but composed of weakly magnetic rocks. Layering of the gabbro-labradorite massif of the Main Ridge is reflected in petrophysical parameters, i. e. endocontact gabbro and gabbronorite show an increased density and magnetic susceptibility compared to leucocratic gabbro and labradorite in the core of the intrusion. Thus, petrophysical data indicate a general increase in the basicity of the rocks towards the bottom of the intrusion.
 The discrepancy between intense geophysical anomalies and physical parameters of near-surface rocks of the block adjacent to the gabbro-labradorite massif of the Main Ridge in the southeast was revealed. This fact indicates a layer of dense rocks under the supracrustal basement rocks (a complex of gneisses and amphibolized volcanic-sedimentary rocks) and rocks of the Imandra-Varzuga structure. This layer can be composed of potentially nickel-bearing rocks of the Imandra complex, including intrusions of the clinopyroxene-wehrlite formation series exposed in some areas.
 According to the configuration pattern of the identified axes of local magnetic anomalies, the Archean blocks are considered isolated areas given the uniform pattern they create, i. e. Belomorian — isometric structures, Kola — linearly extended. Therefore, during transformation of the structural plan in the Paleoproterozoic, the Archean blocks gave differentiated responses to the emerging stress-strain state of the environment and were subject to heterogeneous deformations.
 The performed work, including integrated results of petrophysical studies with the analysis of the structure of geophysical anomalies in the ore region, is relevant in substantiating a strategy for prospecting for new ore occurrences and patterns of their localization, as well as for developing criteria for predicting industrial ores in the region. At the same time, the studies carried out make it possible to answer questions related to the reconstruction of the geodynamic settings that took place during the formation of the region’s crust.

Magnetic and spectrometric studies of Al-Gor area, Southwestern Sinai, Egypt

Al-Gor area is a part of Southwestern Sinai of Egypt. It is considered as one of the most promising areas for mineralization in Egypt, being rich in many mineral deposits of: manganese, iron, copper, zinc, lead, cobalt, nickel, silver, gibbsite, and uranium. Besides, some industrial ore minerals such as kaolin and glass sand,… etc. are also found in this area. The area was studied by Gama-ray spectrometry to trace the radioactive anomalies, their concentrations and their relationship to the existing rocks, and by magnetic survey to study the relationship of radioactive anomalies and their trends with the trends of geological structures. The gamma-ray spectrometric maps show different levels over the surveyed area, which reflect contrasting radioelement contents for the exposed various rock types. The highest radiospectrometric levels are located in the northwest southeast direction and some scattered parts all over the study area. They are mainly associated with Um-Bogma Formation, bearing gibbsite. The study area possesses radiospectrometric ranging between 0.6 and 110.9 Ur as a total-count, 0.1 to 1.8 % for K, 0.1 to 99 ppm for eU and 0.1 to 23 ppm for eTh. The qualitative analyses of magnetic data show the existences of a number of different magnetic anomalies, with different amplitudes and frequencies as well as trends. From the application of spectral analyses of magnetic data, the regional and residual depths of magnetic anomalies can be computed. The first depth represents the regional (deep-seated) anomalies, at about 75 m and the residual (shallow-seated) anomalies, at about 20 m. The trends of the structures as derived from the spectrometric and ratio maps correspond to those inferred from the residual-component magnetic map, which reflects the effect of structures on the concentration of radioactive elements and, consequently mineralization.

Selection of sorption materials for the extraction of nickel and cobalt from the ore of the Gornostaevskoye deposit

Oxidized nickel ores account for the majority of industrial ores suitable for nickel production. The processing of such ores using traditional pyrometallurgical technology is not economically viable due to the low nickel content. One of the most cost-effective methods of processing oxidized nickel ores is sulfuric acid leaching technology followed by sorption extraction. The aim of this work is to establish the kinetic and thermodynamic parameters of the sorption extraction of nickel and cobalt using iminodiacetate chelating ion-exchange sorbents from various manufacturers, to select a desorbing solution and to determine the degree of desorption. The sorption of nickel and cobalt was carried out in a weakly acidic medium from a model solution containing impurities of other metals in static and dynamic modes. The limiting sorption capacity for the studied sorbents is 18-26 mg/g for nickel and 1-2 mg/g for cobalt in the static mode. The sorption capacity in the dynamic mode for nickel is equal to 25.5 g/L for Purolite S 930, 29.2 g/L for Lewatit TP 207, 1.4 g/L, and 1.8 g/L for cobalt, respectively. The best desorption parameters are achieved when using a 2 M sulfuric acid solution. The degree of desorption for sorbents Purolite S 930 and Lewatit TP 207 exceeds 90%. The use of the Lewatit TP 207 sorbent for the extraction of nickel from the leaching solution of nickel ore of the Gornostaevskoye deposit in 5 cycles made it possible to obtain a commercial desorbate with a nickel content of 18 g/L. The use of a part of the commercial desorbate obtained in the previous cycle, further strengthened to the initial concentration of sulfuric acid, for re-extracting nickel from the saturated sorbent during a cyclic process leads to a deterioration in desorption characteristics. It is recommended to remove the commercial desorbate from the process after several cycles of desorption and supply new solution of sulfuric acid for desorption to restore the sorption parameters.

Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

Particle Size Effects on Selectivity in Confined Bed Comminution

Confined bed comminution in high-pressure grinding rollers (HPGRs) and vertical roller mills (VRMs) was previously used preferably for grinding comparably homogeneous materials such as coal or clinker. Meanwhile, it started to complement or even replace tumbling mills in ore beneficiation with ore and gangue particles of rather different breakage behaviors. The selectivity in the comminution of a mixture of particles with different strengths but similar particle size distribution (PSD) of the constituents in a particle bed was investigated earlier. The strength of a material is, however, also a function of particle size. Finer particles tend to be more competent than coarser ones of the same material. In industrial ore processing using confined bed comminution, this effect cannot be neglected but even be exploited to increase efficiency. This paper presents research results on this topic based on experimental investigations with model materials and with natural particles, which were stressed in a piston–die press. It appeared that the comminution result substantially depends on the material characteristics, the composition of the mixture and the PSD of the constituents. Conclusions will be drawn for the future applications of selective comminution in mineral processing.

Development and implementation of new generation cyclone facilities to improve efficiency of iron ore beneficiation and dust collection during its processing

Average iron content in industrial ores decreases from year to year. To use them in the processes of agglomeration and pelletizing, enrichment is necessary, accompanied by abundant emission of dust. A significant amount of iron is lost in tailings at existing magnetic enrichment technologies. Therefore, the development and implementation of new generation cyclone facilities to increase the efficiency of iron ore beneficiation and dust collection during its processing is an urgent scientific, practical and social task. The results of the of new generation cyclone facilities implementation for enrichment of iron ore and dust collection during its processing at the mining and processing factories of Kryvbas (Ukraine) are presented. It has been established that dry magnetic separation of finely crushed ore makes it possible to isolate a magnetic product with an iron content of 64-65%. The yield is up to 45%, the extraction of iron into the magnetic product is 73-75% in two-stage schemes. The degree of dust collection by the new generation cyclone facility is exponentially dependent on the speed of the cleaned flow, number and size of coaxial shells, as well as the diameter of dust particles) and is 1.23 times higher comparing with the previously used cyclone of the same size and capacity. The mobile magnetic field in the recommended cyclone allows to capture magnetic dust with an efficiency of up to 95%, and at the same time the dust is separated into a magnetic component (with an iron content of up to 65%) and a non-magnetic component (up to 12% of Fe) with an initial total iron content of up to 33%.

Processing Converter Slags with Total Utilization of All Components

Currently, almost all plants converted to autogenous smelting of copper-containing concentrates use flotation of converter slags (CS) while leaving 0.55–0.90% Cu in tailings that exceeds the industrial copper ore content. Most of the iron, zinc, lead and silicate components of CS enter dumps. The resultant converter slag concentrate (CSC) contains magnetite having an unfavorable effect on smelting furnace operation, and part of the copper is lost during magnetic separation of the resultant concentrate. A pyrometallurgical method for processing CS with its complete utilization is developed under laboratory conditions. Optimum parameters of the CS-based charge reduction melting are selected by crucible melting: in the first stage at 1250–1300°C copper is extracted into metallized product and the slag composition is adjusted, from which in the second stage at 1450–1500°C iron is reduced and recovered in cast iron. The method provides complete utilization of all slag components. 95% of the copper goes in metallized alloy, and about 0.02% Cu, 2–5% Fe, and 0.2% S remain in the slag of the second reduction stage. The copper-containing alloy is converted, and lead and zinc are transferred into sublimates. The metal-free slag obtained is suitable for use in building objects. In addition, hot slag of stage II depletion may be used as an excellent conversion flux, which is especially important when processing rich matte to blister copper, since this process occurs with an intense thermal balance.

Gold composition and conditions of Southern Ak-Dag gold-sulfide-quartz ore occurrence formation (Western Tuva)

Research subject. The paper presents data on the mineralogical, geochemical and fluid inclusion features of the Southern Ak-Dag gold-sulphide-quartz ore occurrence in Western Tuva.Methods. Mineral formation temperatures, salt composition and fluid salinity were examined using a Linkam TMS-600 cryostage and an Olympus BX 51 microscope. The chemical composition of samples was identified using a MIRA 3 LMU (Tescan Orsay Holding) scanning electron microscope equipped with INCA Energy 450+XMax 80 and INCA Wave 500 microanalysis systems; BSE photos were taken by Tescan Vega 3 and Hitachi ТМ-1000 SEM instruments.Results. The ores under study were found to contain both high-grade and medium-grade gold with an Ag content of up to 17.05 wt %. The average gold fineness comprised 904 ‰, ranging from 830 to 928 ‰. According to fluid inclusion data, gold-sulphide-quartz veins were formed at temperatures of 280–240 °C and pressures of 0.8–1.2 kbar from aqueous fluids having a salinity of 8.6–6.4 wt % NaCl eq. The narrow range of fluid salinity at decreasing temperatures and the prevalence of high-grade gold in sulphide-quartz veins indicate a relatively high rate of mineral formation in a narrow permeable zone without any significant interaction with host rocks or mixing with meteoric waters.Conclusions. Gold mineralization in the Southern Ak-Dag ore occurrence, which was formed within one ore substage, corresponds to the type of gold-galena-chalcopyrite with barite. The established similarity of native gold in the Southern Ak-Dag occurrence and other deposits in the Aldan-Maadyr ore cluster in terms of P-T parameters of ore formation and mineralogical and geochemical features, as well as association of the ore mineralization with beresites, indicate the possibility of discovering industrial ore deposits in the region and confirm its paragenetic relation with Devonian magmatic activity.