Grades Of Ores Research Articles

Compositional peculiarities of the primary, mixed, and oxidized copper ores in gabbroids of the Volkovsky massif (Middle Urals, Russia)

The Ural type magmatic copper deposits in gabbro are assigned to a specific type of copper deposits which exploitation substantially depends on the oxidation degree of the ores, that is often not unambiguous. At the Volkovskoe Cu-Fe-V deposit (Middle Urals, Russia), three technological grades of the copper ores are known, the primary, oxidized, and mixed ones, that are distinguished based on the relative content of Cu2+ in the total copper balance. This paper presents petrological, petrochemical, geochemical, and mineralogical characteristics of natural varieties of the copper ores of the Northwestern zone of the Volkovskoe deposit. It is demonstrated that the criterion for distinguishing the technological grades of the copper ores by the relative Cu2+ content does not reflect the real degree of the supergene oxidation for the selected technological varieties. The results of our research suggest a necessity of studying the copper sulfides in more detail to clarify peculiarities of the redox conditions of the ore formation, to correct the indicators of the primary and supergene copper oxidation degree, which may provide new criteria to determine the boundaries between the technological grades of copper ores, using the Volkovskoe ore deposit as an example.

Flue gas desulfurization by natural recyclable manganese ore in packed bed reactor and its performance prediction by random pore model

Various grades of manganese dioxide ores, as a natural recyclable sorbent, can be used in dry flue gas desulfurization (FGD) at moderate temperatures (350–450 °C). This research provided low- and high-grade manganese dioxide ores to examine SO2 removal in a packed bed reactor. To obtain characteristic parameters of mineral sorbents, XRD, XRF, BET, and mercury porosimetry were employed. Then, kinetic parameters of desulfurization reaction were determined using thermogravimeter analyzer (TGA) and random pore model (RPM) for a single pellet. In desulfurization experiments of simulated flue gas in a packed bed reactor and mass spectrometer (MS) apparatus, the breakthrough times were measured under various operating conditions. The onset of these breakthrough times or life-time of MnO2 reactor for the SO2 removal was predicted successfully by RPM for a packed bed reactor using related kinetic constants from TGA. In addition, reacted sorbets were recycled multiple times after washing with water. Not only does this simple method separate MnSO4 from unreacted sorbents as a valuable byproduct to reduce the FGD cost, but it also improves pore size distribution (PSD) of mineral MnO2 by creating large pores. Modified PSD of this recycled sorbent caused increased breakthrough time.

A lithium ore grade measurement based on the neutron & X-ray bi-modal imaging system

The grades of the minerals significantly affects the energy consumption and chemical pollution along with the beneficiation process for extracting lithium element from the ores. Based on the large neutrons’ macro cross section of the Li2O cluster inside the ores, the grades of lithium ores could be analyzed by the thermal neutron penetrating information. In this work, a bimodal imaging method, which utilizes both the information of penetrating neutrons and X-rays delivered by the same electron linear accelerator driven photoneutron system, was proposed to investigate the lithium concentration of each ore. A linearity R-square value of 0.991 between the results obtained with this method and those from the chemical method has been achieved. The average error in lithium concentration estimation is approximately 0.2 wt percent (wt%). The underlying principles and the experimental results will be elaborated on in this study.

Effect of sodium silicate modified with Fe2+ and Al3+ as dispersant on flotation of molybdenite and chalcopyrite in presence of kaolinite and seawater

Mineral processing is increasingly challenging due to the low grades of ores being processed and the high content of ultra-fine particles, such as clays. Negative effects of the presence of clays on the flotation process include modification of the rheology of slurries, changes in the hydrodynamics of the particle-bubble attachment and slime coating, which reduce the recovery of valuable material. The negative effects have been addressed by using dispersants such as silicates. In this paper, the effect that the presence of silicates modified with Fe2+ and Al3+ has on flotation of molybdenite and chalcopyrite is studied. Microflotation of ores with high content of chalcopyrite and molybdenite were carried out, using kaolinite as ultra-fine particulate system, and conventional and sea water as aqueous medium. Results showed that the effect of modified and unmodified sodium silicates is higher in the flotation of the molybdenite than in the flotation of chalcopyrite. This was corroborated in the measurements of zeta potential in solutions of different ionic charges. The measurements of the zeta potential showed that the addition of sodium silicate modified with Fe2+ maintained the potential in the most negative zone in the different aqueous solutions tested for the case of the chalcopyrite, which would indicate that there is a major repulsion of the precipitates of calcium and magnesium of the surface mineral compared with the measurements in which Al3+ was utilized.

Potential ore possibility of rocks of the deposit Kalmakyr of Almalyk district (Middle Tien-Shan)

The article presents the mineralogical and geochemical features of the types and grades of ores of the porphyry copper deposit Kalmakyr. The chemical, mass spectrometric results of analyzes of selected samples are given. When describing polished sections, ore minerals and their structural and textural features were established. The polyformation and potential ore content of the rocks of the deep horizons of the Kalmakyr deposit was revealed. It has been determined that the change of copper mineralization with depth to copper-molybdenum is due to the change of diorite by monzonitoids. Gold and silver ores appear to be superimposed, young, and associated with basic-felsic dykes.

Technological grades of iron ores as a basis for identification of stratigraphic horizons of the Saksaganska Formation of the Ingulets deposit of the Kryvyi Rih Iron Ore basin

Characterisation of technological varieties of iron ores of Ingulets deposit is given. It is marked that each technological grade corresponds to a certain stratigraphic horizon of the Saksaganka Formation. It is suggested to use this fact for identification of ferruginous and shale horizons of the Saksaganska Formation at the Ingulets deposit

Mineralogical and geochemical features of the Yoshlik deposit (Almalyk-Angren are region, Uzbekistan)

The article presents the mineralogical and geochemical features of the types and grades of ores of the Yоshlik copper-molybdenum deposit. Chemical, mass spectrometric results of analyses of the selected samples are given. Ore minerals and their structural and textural features are established in the description of the anschlifs. The formation of the Yоshlik deposit is associated with small intrusions of diorites and mainly monzodiorites and monzonites, since it is polychronous and polyformational like other copper-porphyry objects of the Almalyk ore region. There is a possible connection between the mineralization of gold, silver and platinoids with plutonic dyke formations.

Совершенствование методов рудоподготовки минерального сырья при освоении сложноструктурных месторождений

The article assesses available methods of managing mineral grades in mining and possible ways to improve the mining efficiency. Assessment criteria for the ore masses are given depending on mineral and chemical composition, structural and other features. The outcomes are presented of developing a methodology of zoning technological types of ores within an open pit with account of complex evaluation of qualitative characteristics of minerals using modern geoinformation technologies. Two main methods, i.e. express and detailed, are proposed for data interpretation in geoinformation systems, which require preliminary creation of a geological database and allow to make reliable assessment and zoning of ores within an open pit based on qualitative indicators. The methods are different in terms of labour intensity, level of detail and the possibility of adjusting the resulting models depending on established or changed requirements towards the mineral grade. An enhanced mining and geological information system allows zoning of technological types and grades of ores within an open-pit with a high degree of reliability, which contributes to the selection of the most effective ore treatment method as part of the ore grade management for specific mining and geological conditions at the planning stage of mining operations. Examples of zoning technological types of ores within an open pit as well as methodological approaches to selecting effective methods of ore grade management are presented for deteriorating mining and geological conditions of deposits and increasing requirements towards the quality of products.

Meeting Energy Demands Through Mining

The Mineral and Mining industry is a huge energy requiring sector which demands connections to a viable electric power origin and reference. With the upsurge of these mineral requests and decreasing valued grades of ores, energy aspiration is approximated to sky-rocket to 36% by the year 2035. It is even projected to accelerate geometrically from the fact that sophistication and powering of the mine locations speeds up the stability into the necessity of energy applications and its requirements derived from fossil fuels utilized to generate electricity. This paper discusses other fossilized fuel-based materials for generation of electricity

Meeting Energy Demands Through Mining

The Mineral and Mining industry is a huge energy requiring sector which demands connections to a viable electric power origin and reference. With the upsurge of these mineral requests and decreasing valued grades of ores, energy aspiration is approximated to sky-rocket to 36% by the year 2035. It is even projected to accelerate geometrically from the fact that sophistication and powering of the mine locations speeds up the stability into the necessity of energy applications and its requirements derived from fossil fuels utilized to generate electricity. This paper discusses other fossilized fuel-based materials for generation of electricity.

ТИПИЗАЦИЯ РУДНЫХ ОБРАЗОВАНИЙ УРАНОВЫХ МЕСТОРОЖДЕНИЙ СТРЕЛЬЦОВСКОГО ТИПА

Based on the results of geological exploration and operational work on the uranium deposits of the Streltsovsky ore field, extensive material on their geological structure has been obtained. This material served as the basis for the analysis of the ore situation in deposits belonging to the hydrothermal type [2; 5]. The deposits are confined to the subsidence caldera and have similar mining and geological characteristics. The use of systems approach during the analysis of the received information has allowed to discharge three bunches of criterions of classification of ore objects: geologic, mining-and-geological and quality. The structural and morphological characteristics of ore formations, elements of their occurrence are classified as geological [3]. As mining and geological features, the following are considered: fracturing of rocks and ores, strength coefficient, stability, average power, variability of ore contours, complexity of ore objects. The qualitative characteristics include the content of uranium in ores, the share of metal reserves in technological grades of ores. In the course of research, the relationships between various classification features that can be expressed by mathematical formulas are obtained. Knowing the quantitative characteristics of ore formations, it is possible to predict the parameters of ore bodies, the use of various geotechnologies for the development of these ore objects. The analysis of all combination of performances hydrothermal uranium ores of the deposits Streltsovsky allows to divide all variety of ore educations into three types: I - powerful, II - medium power, III - low power. The combination of personal performances, inherent in each phylum, enables to justify original technologies of mining for each type of ore educations. Is established, that defining performances of classification of ore educations is the value of a mean power, thus character the convergence of reserves of ore on classes of power for each type is original, mean contents of uranium in ore object and character of convergence of reserves of metal in each class of the contents. Auxiliary performances of ore educations are a parameter of variability of an ore circuit, quotient of complication of ore body, quotient of dispersion of ore bodies in reservoir, the ore circuits1 confirmability from a section to a section. In practical and methodological terms, the proposed classification of ore objects makes it possible: to make a forecast of the development conditions at the stage of geological exploration; to use the regularities and characteristics inherent in each type of ore formations individually when justifying technical solutions

Substantiation of parameters of underground geotechnology in the development of complex structural deposit of various grades of ores

Analysis of mining production activities at the current stage of field development shows an acute deficit in mineral raw materials. At present, most enterprises have exhausted all their prospective reserves and inevitably return to the reserve. Such sites have as a rule a low content of the useful component, are composed of different-grade ores and are located in difficult mining and geological and technical conditions. Their development requires significant capital investment and accordingly this leads to a decrease in the profitability of production. In order to maintain production capacity and extend the life of the field, companies are forced to ensure their development, despite a decrease in overall profits. The search for possible technologies for mining these areas of deposits is an urgent and priority direction for many enterprises. So, in the presented report are the optimal variants of the development of deposits shown, it is represented by different-grade ore bodies, most of them are stacked off-balance ores. The presented solutions make it possible to increase the life of the enterprise by increasing the reserves of previously substandard ores.

Comparative Study of the Flue Gas Desulfurization Using Different‐Grade Natural Manganese Oxides

AbstractDifferent grades of natural manganese ores were used to remove SO2 by dry flue gas desulfurization. The grades of the manganese ores were negatively correlated with the desulfurization performance. The produced MnSO4 enriched on the surface would block the gas diffusion channels during desulfurization. The better desulfurization properties of the low‐grade manganese ores are ascribed to the highly active γ‐MnO2, the porous structure, and the high specific surface area as well as the SiO2 bridge‐like effects. This study supports the cooperative use of sulfur‐containing flue gases and low‐grade natural manganese oxides.

Оценка качественных показателей полезных ископаемых с использованием геоинформационных технологий блочного моделирования

The article presents the results of developing a methodology for evaluating the quality indicators of minerals based on block modeling technologies using modern mining and geological information systems (GGIS). A flowchart for modeling quality indicators of mineral resources is proposed and the results of its use are shown on the example of the Serov complex ore and coal deposits of the Odegeldey section. The presented method of block modeling allows us to zone technological types and grades of ores with high confidence in the quarry space, which contributes to solving the problems of design, planning and production management in the conditions of economic uncertainty, deteriorating mining and geological and mining and technological conditions for the development of deposits. Keywords: mining and geological information system, GIS, quality characteristics of ores, block modeling, geometrization, geological database.

Mineral grades: an important indicator for environmental impact of mineral exploitation

We have collected and analysed grade information for nine metals: copper, gold, iron, lead, manganese, nickel, PGM, tin, and zinc. Based on this analysis, we have developed a proposal of “grade classes”, i.e., what could be considered low-grade, average-grade, and high-grade deposits for all these metals. We discuss the implications of possible developments into the future of the grades of ores, from which these metals are extracted. A focus on high-grade deposits will naturally reduce the environmental impact of mining. For six metals (copper, gold, iron, nickel, PGM, and zinc), we have further analysed the volumes available for the 10% cohort of projects and operating mines with the highest grades. Three metals (iron, PGM, and zinc) show considerable volumes, between 15 and 20% of total metal content in resources in this high-grade percentile. Copper and gold have between 5 and 10% while nickel has only 1.7% in the highest 10% grade percentile.

To blend is a good solution to improve the heat insulation applicability of diatomite ores

BackgroundThe idea of mixing different grades of diatomite ores with certain ratios to obtain blends with tailored minerals constitution that can help on improving their thermal insulation applicability is introduced in this study. In this respect, three diatomite samples were collected for investigation from El-Masakheet, Kasr El-Sagha, and Demia deposits, El-Fayoum, Egypt. Complete chemical and phase analyses of these samples were carried out. The analyses showed that El-Masakheet sample was of low-grade diatomite with excess calcite content. In addition, Kasr El-Sagha and Demia samples were of high-grade diatomite with minor calcite contents. By firing the dried Kasr El Sagha and Demia yellow samples specimens at different temperatures for 1 h, they showed complete destruction at 900 °C. Different amounts of El-Masakheet sample was blended with Kasr El-Sagha and Demia yellow samples. The specimens were subjected to firing at different temperatures for 1 h. The physical properties of the fired mixed specimens were followed up.ResultsResults showed that by blending El-Masakheet sample with 50% mass ratio with Kasr El-Sagha or Demia yellow samples, a pronounced increase in the thermal applicability of the fired blends from 900 to 1100 °C was achieved. In addition, a notable increase in their open porosity was recorded. This improvement was attributed to the change in the minerals constitution ratios in the blends due to the increase in their calcite contents after El Masakheet addition, especially the Ca/Si and Ca/(Al + Si) atom ratios. This change served in forming high melting points minerals like α-wollastonite and akermanite on firing the blends specimens instead of low melting point minerals like cristobalite and alkali aluminosilicate which were formed on firing the high-grade ores alone. Consequently, an increasing in the porosity and the thermal applicability of the new specimens from 900 to 1100 °C was achieved.ConclusionsThe idea of mixing different grades of diatomite ores with certain ratios to obtain blends with tailored minerals constitution can help on improving their thermal insulation applicability and their open porosity. Besides, this concept gave a good solution to get use of the unexploited low-grade diatomite ores, especially of high calcite content.

Characterisation and magnetic concentration of an iron ore tailings

The Quadrilátero Ferrífero mineral province is one of the most important sources of iron ore in Brazil. Nowadays this region produces 65% of the Brazilian iron ore. However, since the 1970s, there has been a continuous depletion of high Fe grade ores, obliging the mineral companies to concentrate low Fe grade ores in order to reach the quality demand of the steel mills. It is estimated that 400kg of tailings is produced for each tonne of beneficiated iron ore. This means there is a very big volume of tailings dumped from industrial plants over the years. Owing to the inefficiency of the industrial operations, the tailings deposited in tailings dam have Fe grades similar to or higher than the Fe grades of some iron ores exploited nowadays (30–45wt%). Therefore, the reprocessing of this material can recover millions of tonnes of discharged Fe and decrease the volume of the existent tailings, which can be interesting for the environmental and economic sustainability of this region. Herein, we present the characterisation of a tailings sample from a gravity concentration circuit of a mine located in northwest of Quadrilátero Ferrífero with the objective of proposing a concentration route for this material. The main characteristics of this tailings sample were: d80=4mm; grades of 30.3wt% Fe and 55.4wt%SiO2, while the identified minerals by XDR, optical microscopy and thermal analyses were quartz, hematite (martitic, lamellar, granular, sinuous, specularitic), goethite (alveolar, amphibolitic, botryoidal), magnetite, kaolinite (5.3wt%) and apatite (0.7wt%). Liberation of quartz for size fraction – 0.150mm was of 80%. Bench magnetic concentration of this material increased the Fe grade up to 23wt% and decreased the SiO2 grade up to 39.4wt% in the obtained concentrates, which is satisfactory for the rougher concentration step.

A Study and Implications on the Potential of Satellite Image Spectral to Assess the Iron Ore Grades of Noamundi Iron Deposits Area

Jharkhand is well known for the largest iron deposits in India. Noamundi is the main deposit, which is associated with shale, keolinite. The rock succession exposed in the southern Singbhum and Keonjhar and lying unconformably over the older metamorphics are known as Iron Ore Series (Ravindrakumar, 1986). This paper relates the assessment of grades of iron ore of the area. The study involves with pre-processing, FLAASH (Fast Line-of-Sight Atmospheric Analysis of Spectral Hypercubes) Atmospheric correction algorithms of EO-1 Hyperion data and evaluating the spectral characteristic by using ENVI 4.7 software package. The position of peak reflectance and absorption trough, continuums removal and absorption band depth are considered for assessment the spectral characters. The strong absorption observed is between the 860 to 900nm wavelength region and peak reflectance is observed in the 750 to 780nm wavelength region of the image spectra. The position of the NIR absorption trough shift to the direction of the longer wavelengths is due to decrease of iron content. Higher values of band depth indicate a better possibility of the iron occurrence. As a result, this spectral study enables the possibility to differentiate the grades of iron ores from hyperspectral satellite images.

Sorting out of Gusevogorsk deposit titaniferous magnetite ore by technological types by methods of geoinformation modeling and preliminary estimation of their washability

A more complete and complex extraction of valuable components in the development of mineral resources is achieved through the separation of technological types and grades of ores, their separate extraction and processing, which allows to increase the yield, quality and nomenclature of commercial products and to raise the economic efficiency of the extraction and preparation processes. An important element of the separate processing of types of ores is the technology used for their zoning by grades in the open-pit space. Innovative direction in the development of the forecast of quality and preparation characteristics of mineral resources is the methods of geoinformation modeling with the use of Geological and Mining Information System technologies. The paper describes the technique of modeling and separation of ores into technological grades on the example of the Gusevogorskoye deposit of titanomagnetites, and presents the method of express ore preparability analysis with the estimation of the degree of contrast of qualitative characteristics.

Geological Controls on High-Grade Iron Ores from Kiriburu-Meghahatuburu Iron Ore Deposit, Singhbhum-Orissa Craton, Eastern India

Numerous iron ore deposits are hosted within the Meso to Neo-Archean banded iron formations (BIFs) extending across the Singhbhum-Orissa Craton, eastern India. Despite the widespread distribution of BIFs, which forms part of the iron ore group (IOG), heterogeneity in their grade and mineral composition is occasionally observed even within a single ore deposit. Kiriburu-Meghahatuburu iron ore deposit (KMIOD), west Singhbhum district, Jharkhand, eastern India is characterized by a dominant hematite (often martitized) occurrence with a total resource of >150 million tonnes (MT) at 62.85 wt % Fe. Very high-grade blue dust ore (friable and powdery hematitewith~67% Fe), high-grade massive, hard laminated hematitic ores (~66% Fe) and medium to low grade goethitic/lateritic ores (50%–60% Fe) are the common iron-ore lithologies in KMIOD. These ores can be distinguished in the field from their physical appearance, meso-scale texture and spatial occurrences with the host rocks along with the variation in chemical composition. The high-grade ores are characterized by high Fe (>62 wt %), low Al2O3 (1.5–2.5 wt %), low SiO2 (2.0–4.5 wt %) and low P (<0.06 wt %). Detailed field studies and laboratory investigations on the ore mineral assemblages suggest that the mineralization of high-grade iron ores at KMIOD is controlled by three major parameters, i.e., lithological, paleoclimatic and structural controls. High-grade iron ores such as blue dust seem to be formed during leaching processes through inter-bedded ferruginous shale and banded hematite jasper (BHJ) occurring within BIFs. Structural elements such as folds, joint network, fracture arrays, local faults and steeply dipping bedding planes are surmised as strong controls for the evolution of different iron ore types from the BHJ. Most of the high-grade ores are concentrated at the hinge portions of second generation folds (F2) owing to the easy access for circulation of meteoric solution along the fractures developed due to release of stresses at the hinge portions aided by supergene ore enrichment processes. The BHJ and interbedded ferruginous shale seem to have been given a significant contribution for the formation of different grades of iron ores over the area. Lithologically, the BIFs are governed by rheological features providing channel ways in the ore enrichment process. The variation in the iron ore mineralogy is caused by the variation in depositional and paleoclimatic environment, structural setting and lithological attributes. Hence, these parameters could be used for future exploration and grade recovery of iron ore resources in the region and in the adjoining areas.