Ore Processing Research Articles

Combination of leaching technologies with conventional ore processing techniques

Combination of leaching technologies with conventional ore processing techniques

Study of Iron Ore Processing Technology of Tamir Gol Deposit in Mongolia

Study of Iron Ore Processing Technology of Tamir Gol Deposit in Mongolia

Морфоструктурные особенности минеральных индивидов в рудах золотосульфидного типа. Забайкальский край

The article deal with the results of a study of the morphostructural features of gold sulfide type ore: the forms of ore mineral deposits, their spatial distribution and relationship. The results of crushed ore research are also reflected. The data obtained make it possible to choose of methods for technological ore processing.

Research on the environmental stability performance of chromite ore processing residue solidified products.

Chromite ore processing residue (COPR) is a hazardous waste because of leachable chromium, especially Cr(vi). Therefore, ascorbic acid (AA) and blast furnace slag (BFS) have been used to detoxify and solidify COPR. On this basis, environmental stability experiments with high temperature and freeze-thaw cycles were carried out to explore the stability performance of a solidified body with 40% COPR. The environmental stability performance was analyzed through changes in edge length, mass loss, compressive strength development, and leaching concentration of Cr(vi). The result indicated that the high-temperature environment had much more effect on the solidified body than the freeze-thaw cycle environment in these four aspects: after being maintained at 900 °C for 2 h, the compressive strength of the solidified bodies reached its minimum value (35.76 MPa). However, in the freeze-thaw cycle experiments, the compressive strength of the solidified bodies consistently remained above 80 MPa, and the leaching of hexavalent chromium was below the limit (5 mg L-1). In addition, X-ray diffraction (XRD) and Fourier transform infrared spectrometry (FTIR) analysis verified that COPR was effectively solidified through physical and chemical means. Moreover, high temperature changes the molecular structure of the solidified body, thus reducing the compressive strength and curing ability of the solidified body, while the freeze-thaw cycle experiment has little effect on it.

О некоторых особенностях региональной поисковой алмазной минералогии

Analysis of the results of carried out investigations of mantle modules in kimberlite diatremes of main diamondiferous regions of the Siberian platform was made. Morphology and chemistry of garnets, chrome-diopsides, clinopyroxenes, picroilmenites, chromites and chrome-spinellids were investigated. Generally, the quantity of diamond association minerals is proportional to diamondiferousness of certain variety of kimberlite for each type of kimberlite rocks composing pipes. It is stated that comprehensive studying of kimberlites and diamond property are very important, because the diamond is a mineral with a broad complex of physical-chemical and crystal-morphological features, reflecting peculiarity of thermodynamic and geochemical conditions of their formation, which can be used as typomorphic indicators. Detailed complex investigations of diamond and its paragenetic accessory minerals allow establishing material-indicative parameters of kimberlite magmatism of various productivity and geologic-structural position of kimberlite bodies, and address issues about primary sources of placer diamonds, as well. Upgrading the line of research on creation of more efficient ore processing flowsheets and providing crystalintegrity technologies, expansion of diamond application areas with consideration of their real structure and physical features, as well as revelation of natural targets with increased quality of diamond raw material, are all related with investigation of primary indicator minerals of kimberlites.

Geotechnical investigations of lead-silver ore processing residues at the Auzelles site, Auvergne (France)

<p>Mining operations generate a significant quantity of mining waste in the form of sterile rocks and processing residues. These mining wastes are typically placed on the surface and can cause geotechnical and geochemical disturbances, as well as contaminants in surface water (through runoff) and groundwater (through infiltration), thus posing environmental risks. This article aimed to characterize the geotechnical properties of lead-silver ore processing residues at the Auzelles site in order to assess their stability and propose recommendations for their management and rehabilitation. The adopted methodology included in situ tests (such as density measurement and permeability) and laboratory analyses (grain size distribution, moisture content, methylene blue test, direct shear test, and standard Proctor test). The results showed a wet density of 1.63 g/cm<sup>3</sup> for the residues compared with 1.65 g/cm<sup>3</sup> for the waste rock, as well as a permeability of the residues measured at 5.5 × 10<sup>-5</sup> m/s, indicating significant drainage capacity. Laboratory analyses revealed that the samples were primarily composed of very silty sands and gravel, classified as B5 according to the Guide to Road Settlements. The cohesion of the residues was found to be zero, while the internal friction angle varied between 28° for the residues and 30° for the foundation soils. These geomechanical properties, particularly density, lack of cohesion, and friction angle values, raise concerns about the long-term stability of the residues. Due to their high permeability and lack of cohesion, the residues are susceptible to mass movement and erosion, which may exacerbate contamination risks. Therefore, it is essential to integrate these parameters into any potential residue stability analysis. Proactive management, based on these results, requires the implementation of appropriate rehabilitation techniques, such as drainage optimization and incorporation of vegetation covers, to minimize environmental impacts and ensure the long-term sustainability of mining waste structures.</p>

Udokan hearth of mineral resources: Factors shaping the quality of atmospheric air

The consequences of the impact of mining and ore processing industries on atmospheric air are acutely negative. Polluted atmospheric air entails a significant environmental risk to human health. The identification of factors that negatively affect the air quality of a mining enterprise and nearby territories actualizes the problem under consideration. The object of the study is the territory of the Udokan hearth of mineral resources. The subject of the study is the factors that shape the quality of atmospheric air. The purpose of the study is to analyze the negative effects of the main factors determining the ecological state of atmospheric air in the conditions of the Udokan hearth of mineral resources. The methodological basis of the research is the complex, structural, factual principles and approaches. The work uses general research methods (analysis, synthesis, generalization), as well as private scientific - factor analysis, which is understood as a method of complex and systematic study of the interaction of factors on the magnitude of performance indicators. The main factors shaping the ecological situation of the study area are identified: climatic, qualitative and quantitative indicators of polluting emissions. The necessity of constant monitoring of the state of the atmosphere for the development and implementation of a set of measures to reduce the negative impact of polluting emissions into the atmosphere is justified. Conclusions. The practical uniformity of the chemical composition of harmful emissions during the implementation of the main technological processes of mining and mining processing industries makes it possible to develop preventive measures to minimize the negative consequences of the development of mineral deposits in the mine atmospheric space.

Reduction of natrojarosite and laterite nickel ore leaching residue composite using palm kernel shell reducing agents at temperatures of 1300-1450℃

Lateritic nickel ore processing through hydrometallurgical route generates a significant amount of residue from the leaching stage. Two examples of hydrometallurgical process residues, namely natrojarosite and leaching residue can potentially be used as secondary raw materials for the iron and steel industry. A relatively high sulfur content of up to 12% is a severe issue because the sulfur threshold value for steel raw materials is 1%. Therefore, it is necessary to reduce the sulfur content in natrojarosite and leaching residue to meet the standards as a secondary raw material for the iron and steel industry. In this research, reduction of natrojarosite, laterite nickel ore leaching residue, and palm kernel shell reducing agents composite was conducted in varying amounts of palm kernel shell reductant of 25-100% using a non-isothermal method at an initial temperature of 1000°C with a final temperature of 1300-1450°C and an isothermal method of 1000°C, 1300°C, and 1450°C for 2 hours. The results showed that an excessive amount of reductant (≥25%) would inhibit the formation of iron metal at macrosize (above 0.35 mm). Reduction, both by non-isothermal and isothermal methods, results in decreasing sulfur content in the metal phase as the reduction temperature increases, but a sulfur-rich matte phase is still observed in all experimental conditions. The proportion of the metal phase produced is getting higher and more separated from the slag phase as the temperature increases. The optimum condition was obtained at a non-isothermal reduction of 1450°C using a 25% reducing agent which resulted in iron and sulfur content in the metal phase of 88.53% and 0.49%, respectively, with a metal-matte phase proportion of 65.56%. In this case, slag was dominated by liquid phase with a FeO content of 7.64% and a viscosity of 7.313 PaS.

Enigma of Nickel Export Ban: Understanding Its Impact through Input-Output Analysis

The nickel ore export ban policy has drawn pros and cons in various circles. This study aims to analyze the impact of the nickel ore export ban on other sectors of the economy and the interrelationship between one sector and another. This study uses secondary data in the form of Indonesia's Input Output Table Total Transactions at Basic Prices in 2016 derived from BPS publications and data on the number of Ferro-nickel exports in 2020 derived from UNData publications, which are then analyzed using the input-output method and presented using descriptive quantitative analysis. Based on the research results, electricity and gas procurement are the economic sectors with the most significant backward linkage. In contrast, the manufacturing sector achieves the most significant forward linkage value. In addition, the electricity and gas procurement sector also has the most significant output multiplier value, followed by the construction and manufacturing sectors. The increase in Ferro-Nickel exports due to the nickel ore export ban has considerably impacted the economy regarding both domestic and import output, especially in the manufacturing industry sector. Thus, nickel ore processing activities depend on capital goods and other imported raw materials. The study's implication shows that the export of Ferro-Nickel as part of the mining and quarrying sector impacts the output of other sectors to increase overall economic growth.

Dynamic system employed for predicting noise emission at new constructed mineral ore processing plant

Abstract The impact of noise can arise from the operation of a mineral ore processing plant in the mining industry, such as PT Freeport Indonesia. The use of advanced technology in modern industry, like SAG#3, has increased production productivity but can also lead to noise emission issues that may endanger workers’ health. This research aims to project the impact of noise in the workplace at a new mineral ore processing plant using dynamic system analysis. Noise sampling was conducted using a sound level meter instrument following SNI 7231:2009. After data collection, dynamic system analysis was performed using Vensim Pro software, involving steps such as causal loop design, stock flow diagram formation, and model verification testing. The analysis results indicate that the noise level exceeds the permissible exposure limit, measuring at 85 dBA. Therefore, the implementation of a Hearing Conservation Program (HCP), personal protective equipment (PPE) policies, and periodic noise control policy evaluation are crucial steps in reducing the impact of noise on employees. This study highlights the need for concrete actions by the company, such as improving the effectiveness of the HCP, enforcing stricter PPE policies, and conducting regular evaluations. Consequently, the company can create a safer work environment and reduce the health risks associated with noise exposure in the workplace.

LED-driven photocatalytic degradation of tetracycline by chromite ore processing residue (COPR): Mechanism, pathway, toxicity assessment

Soda-based chromite ore processing residue (COPR) is a hazardous waste produced from chromium salt plants. In this study, detoxified water-washed chromite ore processing residue (DW-COPR) was investigated as a catalyst to activate peroxymonosulfate (PMS) to degrade tetracycline (TC) in the presence of visible light. Performance, mechanism, pathways of TC degradation process in the DW-COPR/PMS/light catalytic system and the toxicity analysis of the intermediates were systematically analyzed by EPR, LC-MS, and Toxicity Estimation Software Tool (T.E.S.T). The results indicated that the DW-COPR had excellent properties on TC degradation and practical application, with optimal efficiency of 94.37% in the DW-COPR/PMS/light system, due to the combined participation of radical •OH, SO4•-, O2•-, 1O2, h+, and e-. Simultaneously, the study outlined four potential degradation pathways for TC: deamidation, hydroxylation, benzene ring opening, and carbonylation. It was revealed that the naturally formed spinel structure in DW-COPR played a dominant role in the reusability and recyclable performance. The present work provides a new perspective on the high-value-added resourcing of DW-COPR as catalyst.

An analysis of the interaction of infiltration waters from tungsten ore processing tailings and limestone

An experimental plant designed to study the interaction of acidic pore waters in tailings ponds was developed. The study showed that processing tailings of the Dzhida tungsten-molybdenum plant contain residual ore mineralization, which decomposed during long-term storage. The filtrate obtained by washing sand with distilled water contains sulfur, aluminum, iron, manganese, zinc, copper, cadmium and other components. To displace all dissolved substances from the pore space of sand, the threefold volume of water is sufficient. When the filtrate is neutralized with limestone under the dynamic conditions, amorphous compounds of iron, calcium, aluminum, sulfur, silicon, and fluorine are precipitated and the minerals gypsum, dolomite, and smithsonite appear. In addition, precipitation of non-ferrous and rare earth elements occurs on the surface of limestone. The study revealed an europium anomaly. To precipitate rare earth elements from a solution, it is necessary to use substances with an active surface.

Methods of ore processing by microwave radiation

Methods of ore processing by microwave radiation

Поиск резервов повышения производительности экскаваторно-автомобильных комплексов с применением компьютерного моделирования

An analysis of the performance indicators of the main high-performance excavators used at leading coal mines and iron ore mining and processing plants in Russia showed that the actual average monthly productivity of excavators achieved at mining enterprises is lower than the calculated technical one by 30% or more. To increase it, it is necessary to minimize negatively influencing factors and optimize the operation of the excavator-automobile complexes. The possibility of this is confirmed by the information available in the scientific and technical literature on record productivity indicators established at mining and processing plants and open-pit mines during full-scale experiments. The choice of excavator-automobile complexes is a relevant and important task at the design stage of new enterprises, or justification of the optimal parameters of the loading and hauling equipment in conditions when the existing quarries are going deeper or expanding and the productivity of mining and processing plants is increasing, as well as for comparing various technological options for the development of deposits. One way to solve this issue may be computer simulation of the functioning of both the individual elements (excavators, dump trucks, excavatorautomobile complexes, etc.) and the quarry transport system as a whole. The Institute of Mining of the Ural Branch of the Russian Academy of Sciences has developed the In-Pit Transport System software suite, aimed, among other things, at solving these problems.

Trash to Treasure: Recovery of Trace Platinum from Industrial Process Solutions

Concerns about metal scarcity are becoming more prevalent due to the depletion of the world’s natural resources and increased demand of metal productions. Therefore, more efficient and innovative methods for metal recovery are required. Among the traditional hydrometallurgical methods [1], the electrochemical recovery of metals - like electrowinning - provide a state-of-the-art basis for sustainable metals recovery through the use of renewable electricity. In electrowinning, the metals are recovered by electrodeposition from concentrated and purified leaching solutions. Nevertheless, the process solutions in the final stages of hydrometallurgical or pyro-hydrometallurgical operations still contain precious metals Ag, Au, and platinum group metals at very low concentrations (< mg L-1 or < μg L-1). For example, platinum - a critical element in photocatalysts for the hydrogen economy, electronics and medical applications – can also be recovered from such trace concentrations to prevent both material loss and to provide additional value. Recently, electrodeposition and redox replacement (EDRR) - method has been applied for selective precious metal recovery from lower-grade raw materials-hydrometallurgical process solutions [2]. During EDRR, a sacrificial metal with less nobility is first deposited through electrodeposition, then the precious metal is recovered onto the electrode surface through RR reaction, driven by the difference in reduction potentials between the two metals. EDRR can be tailored through operational parameter selection, thereby allowing an optimized purity of recovered metals and even controllable preparation of metal coatings, nanoparticles, high-value-added functional surfaces (photocatalyst, corrosion resistant) directly from industrial process solutions [2].In the course of previous studies, it has been observed that metal reduction may also occur via aqueous reduction close to the electrode surface [3]. If actual electrodeposition of sacrificial species into metallic form is not indispensable before the metal recovery in the RR step, process with lower energy consumption and higher purity end-product may be realized via aqueous reduction (EAR). In the current study, multivalent iron was selected as reductive species during EAR-process to recover dissolved platinum. Specifically, dissolved Fe(III) in chloride-based media is first electrochemically reduced to a lower oxidation state Fe(II), then in the RR step, the produced aqueous Fe(II) species serve as reductant to trigger the consequent deposition of Pt on the electrode. As a result, the EAR method succeeded in recovering platinum on the electrode. Chloride concentration was shown to have a substantial impact on the platinum recovery, in terms of both recovery efficiency and structure of deposits, which is suggested to be derived from the Fe and Pt complexation in chloride-based media. The recovery of Pt based on EAR also varies with EAR process parameters, e.g., the applied potential and time to reduce Fe(III), or RR time. The influence of other species (concentrations) and the pH in solution were systematically studied as well, further paving the way to apply EAR method in other metal recovery system. Acknowledgements This work was supported by the Academy of Finland project EARMetal (LC, KY, ML: 339979 and LC, KY, JV: 342080). The RawMatTERS Finland Infrastructure (RAMI) funded by the Academy of Finland and based at Aalto University is also acknowledged. Reference [1] M.E. Wadsworth, J.D. Miller, Hydrometallurgical Processes. In: H.Y. Sohn, M.E. Wadsworth (Eds), Rate Processes of Extractive Metallurgy, Springer, Boston, 1979. https://doi.org/10.1007/978-1-4684-9117-3_4[2] L. Cui, K. Yliniemi, J. Vapaavuori, M. Lundström,Recent developments of electrodeposition-redox replacement in metal recovery and functional materials: A review, Chem Eng J. (2023). https://doi.org/10.1016/j.cej.2023.142737 [3] I. Korolev, S. Spathariotis, K. Yliniemi, B.P. Wilson, A.P. Abbott, M. Lundström, Mechanism of selective gold extraction from multi-metal chloride solutions by electrodeposition-redox replacement, Green Chem. 22 (2020) 3615–3625. https://doi.org/10.1039/D0GC00985G

The Mining Industry's Role in Enhanced Weathering and Mineralization for CO2 Removal.

Enhanced weathering and mineralization (EWM) aim to remove carbon dioxide (CO2) from the atmosphere by accelerating the reaction of this greenhouse gas with alkaline minerals. This suite of geochemical negative emissions technologies has the potential to achieve CO2 removal rates of >1 gigatonne per year, yet will require gigatonnes of suitable rock. As a supplier of rock powder, the mining industry will be at the epicenter of the global implementation of EWM. Certain alkaline mine wastes sequester CO2 under conventional mining conditions, which should be quantified across the industry. Furthermore, mines are ideal locations for testing acceleration strategies since tailings impoundments are contained and highly monitored. While some environmentally benign mine wastes may be repurposed for off-site use─reducing costs and risks associated with their storage─numerous new mines will be needed to supply rock powders to reach the gigatonne scale. Large-scale EWM pilots with mining companies are required to progress technology readiness, including carbon verification approaches. With its knowledge of geological formations and ore processing, the mining industry can play an essential role in extracting the most reactive rocks with the greatest CO2 removal capacities, creating supply chains, and participating in life-cycle assessments. The motivations for mining companies to develop EWM include reputational benefits and carbon offsets needed to achieve carbon neutrality.

Evaluation of lactate esters as novel biobased and environmentally friendly flotation frothers within PGM ore processing

As the mining industry moves towards more sustainable processing practices, the consideration of environmentally friendly reagents becomes important. Lactate esters are produced from renewable feedstock and considered green reagents because of their benign toxicological and environmental impact. Lactate esters may be considered to be suitable as flotation frothers owing to their heteropolar nature and the fact that they contain similar functional groups as commonly used industrial frothers. The most promising lactate ester, PURASOLV® BL, developed a stable froth with a lower level of entrainment than the commonly employed PPG frother, resulting in good metal recoveries and grades thereof. Utilizing lactate esters as novel green flotation frothers will attribute to the desired and mandatory shift towards greener reagents in PGM ore processing.

Оценка потенциала восстановления экологического состояния природных экосистем, нарушенных при освоении георесурсов, по спутниковым данным

The factors of environmental state restoration of the natural ecosystems disturbed as the result of mining mineral deposits were investigated using the case study of the phytocenosis formed on the enclosing dam of the apatite-nepheline ore processing waste storage in the Khibiny group of deposits according to the technology developed in the Mining Institute of the Kola Scientific Center of the Russian Academy of Sciences for the restoration of disturbed lands through creation of a biologically active environment without deposition of a fertile layer. Based on the data of satellite observations of the monitoring sites during the vegetation period, the impact of relief as well as the heat and moisture availability on the state of the emerging vegetation cover was studied using gradient transects of different exposures along the height of the enclosing dam slope. The spatial resolution of the satellite images was harmonized using the enhanced pan-sharpening procedure with the minimum characteristic size of the dam slope elements and the representativeness of the data obtained when assessing the vegetation cover condition using the vegetation index and the moisture stress index was ensured. Generalization was made of the relationship between the parameters characterizing the vegetation cover state and abiotic factors of its formation using a neural network model. Two artificial neural networks were trained to predict the vegetation and the plant moisture stress indices using the data set obtained from processing of visible, infrared and thermal spectral channels of satellite images of the monitoring sites. The neural network model shows that the vegetation index of the emerging vegetation cover is antibate to the plant moisture stress index - the dominant factor in restoration of the environmental state of the investigated site, and to the surface temperature of the enclosing dam of the tailing dump. Dependence of the predicted moisture stress of the phytocenosis formed ontop the enclosing dam slope on the elevation and exposure was used to assess the potential of its restoration to the forest succession stage corresponding to the phytocenosis of the surrounding natural environment. Zoning of the tailing dump according to the potential for restoration of the environmental state was performed in order to support the decision-making process when planning environmental protection measures.

Comparative review on the technologies of briquetting, sintering, pelletizing and direct use of fines in processing of ore and technogenic materials

Comparative review on the technologies of briquetting, sintering, pelletizing and direct use of fines in processing of ore and technogenic materials

Tools for the metal processing of the Alakul population of the forest-steppe Tobol River basin

The paper presents the results of the study of a tool complex associated with metalworking from the sites of the Alakul Culture of the forest-steppe Tobol River basin — the settlements of Kamyshnoe 1 and 2, Uk 3, Nizhneingalskoe 3, and Zolotoe 1. The Alakul antiquities, in general, date to 1900–1450 BC. The purpose of this work is the consolidation and clarification of information on the metalworking of the Alakul population of the forest-steppe Tobol basin. For this purpose, collections of trade tools of the aforementioned Alakul settlements were revisited; the tools used in the production in question were identified; the signs of their wear, documented by a series of microphotographs, were characterised; and groups of the tools were identified according to their functional feature. The main research method was experimental-traceological. It implies, firstly, the study of traces of wear, their mutual occurrence and specifics of the location on the tools; secondly, the comparison of the obtained characteristics with experimental data. In the work, theoretical and experiential concepts of the methodology and classification schemes developed by S.A. Semenov, G.F. Korobkova, and V.V. Kileynikov were employed. To verify the traces of wear on archaeological tools, experimental reference samples of the tools were used, obtained during many years of work and stored in the Tyumen Scientific Centre SB RAS. As analogies, published results of the experiments and experimental and traceological studies of similar tools from territorially close Bronze Age sites were used. As the result, forging tools (hammers for cold and hot forging of castings, smoothers) and abrasive tools were identified; their technological characteristics and distinctive signs of wear marks were clari-fied. A set of tools in one quantity or another was recorded at each of the studied sites; therefore, the blacksmith production was quite developed also on the periphery of the Alakul Culture. Additional arguments were obtained in favour of the hypothesis that the ore processing was taking place in the immediate vicinity of its sources, and the metal could have been supplied to the re-mote villages already in a ‘finished’ form; there, the products were cast, forged, and finished. Analogies to the studied tools are known from the earlier Petrovka and Sintashta complexes of the Southern Trans-Urals. Thus, we can talk about common patterns in the manufacture and use of metalworking tools during the Bronze Age in the Trans-Urals territory.