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Date submitted2024-03-22
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Date accepted2024-09-24
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Date published2025-02-25
Behaviour of cerium (III) phosphate in a carbonate-alkaline medium
- Authors:
- Tatyana E. Litvinova
- Stepan A. Gerasev
The article investigates the behaviour of rare earth metals in carbonate-alkaline systems. The results of experimental studies on rare earth element extraction from phosphogypsum, a large-tonnage industrial waste forming in production of phosphoric acid are presented. Using the liquid phase leaching method, it was possible to extract more than 53 % of rare earth elements from old phosphogypsum and more than 69 % from fresh phosphogypsum due to solid phase treatment with a 4 mol/l potassium carbonate solution at temperature 90 °C. The behaviour of model cerium (III) phosphate in a carbonate-alkaline medium is characterized: a solubility isotherm is obtained as well as the dependences of the degree of cerium extraction into solution on temperature, carbonate ion concentration, interphase ratio, stirring intensity, and pH. The ability of soluble rare earth element complexes to precipitate over time was established, which was confirmed using cerium and neodymium as an example. Within 240 h after the end of the experiment, approximately 25 % of cerium and 17 % of neodymium were precipitated from the liquid phase. A similar property was recorded in representatives of the light group and was not noted in elements of the heavy group. The ability to self-precipitate in future can serve as a basis for developing an alternative approach to separating rare earth metals into groups after extraction in a carbonate ion medium. Also, based on the analysis of experimental data, the mechanism of cerium (III) phosphate dissolution in a carbonate-alkaline medium was characterized. An assumption was made that rare earth metal phosphates dissolve sequentially passing into an insoluble carbonate and then into a soluble carbonate complex.
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Date submitted2024-05-30
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Date accepted2024-10-14
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Date published2024-11-12
Thermodynamic modelling as a basis for forecasting phase states of hydrocarbon fluids at great and super-great depths
The possibility of discovering oil and gas occurrences at great (more than 5 km) and super-great (more than 6 km) depths is considered in two aspects. The first one is the preservation conditions of large hydrocarbon accumulations forming at depths to 4 km and caused by different geological and tectonic processes occurring at great and super-great depths with partial oil-to-gas transformation. It was ascertained that among the factors controlling preservation of liquid and gaseous hydrocarbons are the temperature, pressure, subsidence rate (rate of temperature and pressure increase), time spent under ultrahigh thermobaric conditions, and initial composition of organic matter. The possibility of existence of liquid components of oil at great and super-great depths is characteristic of sedimentary basins of China, the Gulf of Mexico, the Santos and Campos basins on the Brazilian shelf, and in the Russian Federation it is most probable for the Caspian Depression, some submontane troughs and zones of intense accumulation of young sediments. Determination of critical temperatures and pressures of phase transitions and the onset of cracking is possible using the approach considered in the article, based on estimation of organic matter transformation degree, kinetic and thermobaric models taking into account the composition of hydrocarbon fluid. The second aspect is the estimation of composition of hydrocarbons associated with rocks forming at great depths or rocks transformed under conditions of critical temperatures and pressures. This aspect of considerable science intensity can hardly be considered as practically significant. The study focuses on the investigation of the possibilities of thermodynamic modelling and the use of alternative methods for studying the transformation degree of liquid formation fluid into components of the associated gas through the example of two areas with identified oil, condensate and gas accumulations.
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Date submitted2024-05-13
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Date accepted2024-09-05
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Date published2024-11-12
Potential trace element markers of naphthogenesis processes: modeling and experimentation
With the growing demand for hydrocarbon energy resources, there is a need to involve oil fields at deeper horizons in processing and increase the profitability of their development. Reduction of expenses on prospecting works is possible at revealing and substantiation of physicochemical markers of the naphthogenesis processes. One of the key markers is the transition metals content, which are both a measure of oil age and markers of potential associated processes in the migration and formation of hydrocarbons in the Earth's strata. The elemental composition of samples of oil and reservoir rocks of the Timan-Pechora field was studied. Based on the results of thermodynamic modeling, plausible processes of contact rock minerals transformation were proposed. Based on the results of molecular modeling the probable structure of vanadium and nickel host molecules in the heavy fraction of oils is proposed. The ratios of transition metal and sulfur contents were experimentally established, and assumptions about possible mechanisms of formation of deep hydrocarbon reservoirs were made. Analysis of the obtained ratios of transition metal contents in reservoir rocks and oil samples allowed to suggest possible processes of mantle fluids contact with the host rock and subsequent accumulation of hydrocarbons on sorption active rocks. According to the combined results of experimental and theoretical studies it was found that polymers of heavy fraction more selectively capture vanadium, which indicates the predominance of vanadium content in oil-bearing rocks in relation to the content of nickel. In this case, oil acts as a transport of transition metals, leaching them from the bedrock.
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Date submitted2024-04-08
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Date accepted2024-06-13
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Date published2024-12-25
Analysing the problems of reproducing the mineral resource base of scarce strategic minerals
The results of studying the scarcity of strategic minerals in the Russian Federation are presented, domestic consumption of which is largely provided by forced imports and/or stored reserves. Relevance of the work is due to aggravation of the geopolitical situation and a growing necessity to meet the demand of national economy for raw materials from own sources. Analysis of the state of mineral resource base of scarce minerals in the Russian Federation was accomplished, problems were identified and prospects for its development were outlined taking into account the domestic demand for scarce minerals, their application areas and the main consumers. Reducing the deficit through the import of foreign raw materials and the development of foreign deposits does not ensure the reproduction of the domestic mineral resource base, independence of the country from imported raw materials as well as additional competitive advantages, economic stability and security. It was ascertained that a major factor holding back the development of the mineral resource base is insufficient implementation of new technological solutions for the use of low-quality ore. Improving the technologies in the industry is relevant for all types of scarce minerals to solve the problem of reproducing their resource base. Taking into account the prospects for the development of the resource base for the minerals under consideration (manganese, uranium, chromium, fluorspar, zirconium, titanium, graphite) requires a set of legal and economic measures aimed at increasing the investment attractiveness of geological exploration for subsoil users at their own expense without attracting public funding. The proposed measures, taking into account the analysis of positive experience of foreign countries, include the development of junior businesses with expansion of the “declarative” principle, the venture capital market, various tax incentives, preferential loans as well as conditions for the development of infrastructure in remote regions. The proposed solution to the problem of scarcity of strategic minerals will make it possible in future to present measures to eliminate the scarcity of certain types of strategic minerals taking into account their specificity.
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Date submitted2024-03-30
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Date accepted2024-06-13
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Date published2024-07-04
Organotin pollutants in emerging coastal-marine sediments of the Kaliningrad shelf, Baltic Sea
Based on two years of monitoring of modern bottom sediments of two sections of the Kaliningrad shelf of the Baltic Sea – “Curonian Spit” and “Northern Sambian” – an assessment of the sources of pollution with organotin compounds (OTs) and heavy metals was carried out. The content of individual organotin compounds and OTCs spectra obtained by gas chromatography with mass spectrometry of relatively coarse-grained bottom sediments indicate the presence of organotins in significant quantities – the total OTs content (ΣOTs) is from 0.6 to 8.3 ng/g. However, the content of tributyltin (TBT), the main component of anti-fouling systems for marine vessels and the most dangerous endocrine-disrupting compound among the hazardous substances for marine ecosystems, is at a low level (0-2.3 ng/g) in all studied samples and has not increased over the two-year observation period (biodegradation index 1.7-12.4). At the same time, the presence of abnormally high concentrations of mono-, triphenyl- and tricyclohexyltin in the sediments of the ”Northern Sambian” site (up to 30, 7 and 6.4 ng/g, respectively) indicates an additional source of pollution of coastal waters and shelf sediments (for example, plastic litter and agricultural runoff). The absence of significant shipping in the study areas ensures a consistently low level of pollution with tributyltin and its derivatives (less than 0.3 and 2.3 ng/g of TBT in 2017 and less than 0.1 and 1.3 ng/g in 2018 for the sites “Curonian Spit” and “Northern Sambian”, respectively), which indicates the activity of the processes of TBT transformation and self-cleaning of sandy sediments. However, the identified trends and their predictive accuracy require long-term observation and monitoring of the sediment environment using data on the deep-water part of the shelf, enriched in clay and humus components.
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Date submitted2022-08-10
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Date accepted2023-02-28
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Date published2024-02-29
Selection of the required number of circulating subs in a special assembly and investigation of their performance during drilling of radial branching channels by sectional positive displacement motors
The task of sludge removal to the surface during construction of directional and horizontal wells and strongly curved radial channels is relevant. For stable operation of technical system “Perfobore”, it is proposed to use a circulating sub that ensures efficient cleaning of channel wellbore from the drilled rock. Two schemes of technical system “Perfobore” are considered, consisting of two seven-meter coiled tubing, a positive displacement motor, a bit and one circulating sub in the first scheme and two subs in the second scheme. For each of the schemes CFD modeling was implemented to determine values of pressure and speed. It was found out that the use of two circulating subs in the assembly is more efficient. In order to confirm the numerical experiment, bench tests were carried out. It was determined that the designed circulating sub can eject up to 25 % of pumped drilling fluid. The bench tests of full-size technical system “Perfobore” for drilling 14-meter channels with two circulating subs showed that the axial load on positive displacement motor produced by hydraulic loader was 3000 N and pressure drop depending on flow rate was 1.5-2.0 MPa. This allows the motor to operate at maximum power.
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Date submitted2022-06-09
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Date accepted2022-11-17
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Date published2022-12-29
Drilling of deep and ultra-deep wells for prospecting and exploration of new raw mineral fields
Scientific and technological progress over the last century has led to an enormous increase in the consumption of minerals, including energy resources. Most of the exploited oil and gas fields are already considerably depleted, so it is necessary to search for new hydrocarbon resources, particularly at great depths. Deep drilling plays a special role in solving this problem. The article considers the world and Russian experience of ultra-deep wells drilling. The methods and technologies used in the construction of wells, as well as complications and accidents occurring during their drilling were analyzed. The analysis revealed that the existing limitations for drilling parameters of deep and ultra-deep wells are caused by the technical characteristics of surface and bottomhole drilling equipment, which do not meet the extreme drilling conditions. The directions for development of deep and ultra-deep well drilling machinery and technologies are suggested. The notion of extreme rock and geological drilling conditions is introduced, which describes drilling in conditions of hydrostatic pressure of flushing fluid column and high bottomhole temperature both at stable and unstable wellbore conditions, coming close to the upper limit of operating technical characteristics of bottomhole assembly, the drill string and flushing fluid.
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Date submitted2022-06-20
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Date accepted2022-09-06
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Date published2022-11-03
Adaptive approach formation using machine vision technology to determine the parameters of enrichment products deposition
In this paper, an adaptive approach has been developed for automatic initialization of the thickening curve using machine vision technology, which makes it possible to determine with high accuracy the material parameters necessary for the design of thickening and clarification apparatuses. Software has been developed that made it possible to search for the coordinates of the condensation critical point in automatic mode. Studies on two samples of materials (tailings of apatite-containing ores and gold-bearing concentrate) were carried out and made it possible to statistically prove the reproducibility of the results obtained using the parametric criteria of Fisher and Bartlett. It has been established that the deposition curves are approximated with high accuracy by the Weibull model, which, together with the piecewise linear approximation, makes it possible to formalize the method for determining the critical point coordinates. The empirical coefficients of the Weibull model for two samples are found, and the final liquefaction and settling rates of the studied materials are determined.
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Date submitted2021-07-19
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Date accepted2022-05-31
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Date published2022-07-13
Study of a set of factors influencing the error of surveying mine facilities using a geodesic quadcopter
The factors influencing the qualitative and quantitative components of the result of surveying in open-pit mining using a quadcopter were identified and systematized, and the mathematical dependence of the influence of factors on the final error of surveying was determined. After a large number of field observations – numerous flights of a geodesic quadcopter over mining facilities – the subsequent mathematical justification of the results of the aerial photogrammetric surveying was made, which allowed to analyze the degree of participation in the final accuracy of the survey of each of the considered factors. The results of this study demonstrate the source of errors, which provide the surveyor with the opportunity to efficiently and competently carry out pre-flight preparation and planning of fieldwork. The study and subsequent consideration of the factors affecting the accuracy of surveying with the use of an unmanned aerial vehicle are the basis for the subsequent development and formation of a methodology for using a geodesic quadcopter in the conditions of open-pit mining.
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Date submitted2021-03-23
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Date accepted2022-01-24
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Date published2022-04-29
Justification of the technological scheme parameters for the development of flooded deposits of construction sand
- Authors:
- Vladimir V. Ivanov
- Denis O. Dzyurich
The article describes the main types of technological schemes for working out the flooded strata of sand deposits using hydraulic shovel excavators. The analysis of scientific and technical literature describing the experience of using hydraulic shovel excavators in the open-pit mining, including pits for the extraction of construction sand, has been carried out. The proposed technological scheme is that the development of reserves of the flooded strata without preliminary water reduction is carried out by a hydraulic shovel excavator from under water by a downward digging with the storage of the extracted rock mass in bulk (for dewatering), placed in such a way that when working out the next mining bench width, it is located within the working area of the excavator for simultaneous processing of the next bench width and loading of dewatered sand from the pile. Calculations of the parameters of the operating platform and the excavator block of the proposed technological scheme for conducting open-pit mining were carried out. The dependence for determining the minimum length of the mining operations front of an excavator for drawing up a technological scheme of operation of a backhoe hydraulic excavator on working out the flooded strata with the pile formation for dewatering sand and its subsequent uploading from the pile by the same excavator is presented.
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Date submitted2021-05-19
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Date accepted2022-04-07
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Date published2022-04-29
On the possibility of reducing man-made burden on benthic biotic communities when mining solid minerals using technical means of various designs
The paper analyses features of the species composition and diversity of biotic communities living within the ferromanganese nodule fields (the Clarion-Clipperton field), cobalt-manganese crusts (the Magellan Seamounts) and deep-sea polymetallic sulphides (the Ashadze-1, Ashadze-2, Logatchev and Krasnov fields) in the Russian exploration areas of the Pacific and Atlantic Oceans. Prospects of mining solid minerals of the world’s oceans with the least possible damage to the marine ecosystems are considered that cover formation of the sediment plumes and roiling of significant volumes of water as a result of collecting the minerals as well as conservation of the hydrothermal fauna and microbiota, including in the impact zone of high temperature hydrothermal vents. Different concepts and layout options for deep-water mining complexes (the Indian and Japanese concepts as well as those of the Nautilus Minerals and Saint Petersburg Mining University) are examined with respect to their operational efficiency. The main types of mechanisms that are part of the complexes are identified and assessed based on the defined priorities that include the ecological aspect, i.e. the impact on the seabed environment; manufacturing and operating costs; and specific energy consumption, i.e. the technical and economic indicators. The presented morphological analysis gave grounds to justify the layout of a deep-sea minerals collecting unit, i.e. a device with suction chambers and a grip arm walking gear, selected based on the environmental key priority. Pilot experimental studies of physical and mechanical properties of cobalt-manganese crust samples were performed through application of bilateral axial force using spherical balls (indenters) and producing a rock strength passport to assess further results of the experimental studies. Experimental destructive tests of the cobalt-manganese crust by impact and cutting were carried out to determine the impact load and axial cutting force required for implementation of the collecting system that uses a clamshell-type effector with a built-in impactor.
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Date submitted2021-03-30
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Date accepted2021-07-27
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Date published2021-10-21
Integrated development of iron ore deposits based on competitive underground geotechnologies
- Authors:
- Vladimir L. Trushko
- Olga V. Trushko
The article presents an analytical review of the current state of the iron ore base of the ferrous metallurgy of Russia and the world, identifies the largest iron ore provinces and iron ore producers. The promising directions of development and improvement of the quality of the iron ore base of Russia and the features of the development of new deposits of rich iron ores are identified. Effective technologies for the development of rich iron ores deposits that ensure an increase in production volumes are proposed. The geomechanical justification of rational technological parameters that are easily adapted to changes in mining and geological conditions has been performed. Based on the results of field studies, the use of an elastic-plastic model with the Coulomb – Mohr strength criterion for modeling changes in the stress-strain state of an ore rock mass during mining operations is justified and recommendations for ensuring the stability of mine workings are developed. Effective engineering and technical solutions for the complex development and deep processing of rich iron ores with the production of fractionated sinter ore, which increases the efficiency of metallurgical processes, the production of high-grade iron oxide pigments and iron ore briquettes, which increase the competitiveness of iron ore companies and the full use of the resource potential of deposits, are presented.
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Date submitted2020-06-16
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Date accepted2021-03-29
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Date published2021-09-20
Empirical regularities investigation of rock mass discharge by explosion on the free surface of a pit bench
- Authors:
- Igor A. Alenichev
- Ruslan A. Rakhmanov
Minimizing the discharge of blasted rock mass into the developed space of the pit is a very relevant area for study, as it allows to increase the processability of work and reduce the cost of mining. The article presents the results of experimental industrial explosions, during which the study of this issue was conducted. The main purpose of the work was to establish the key factors affecting the volume of rock mass discharge to the pit haulage berm. During the analysis of the world experience of research on this topic, the key factors affecting the formation of collapse and discharge – natural and technological – are identified. The method of conducting experiments and collecting data for analyzing the influence of technological parameters of location, charging and initiation of wells on the volume of rock mass discharge is described. It is established that the main discharge to the pit haulage berm is formed by the volume of rock mass limited by the prism of the slope angle. With a sufficient rock mass displacement from the edge of the bench crest towards the center of the block, only the wells of the 1st and 2nd rows participate in the discharge formation. Empirical dependences of the total volume of rock mass discharge on the length of the block along the bench crest, the specific consumption of explosives, the size of a rock piece P 50 and the rate of rock breaking are obtained. The obtained results can be used to design the parameters of the drilling and blasting operations (DBO), as well as to predict and evaluate the possible consequences of a mass explosion in similar mining and geological conditions.
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Date submitted2020-12-11
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Date accepted2021-03-30
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Date published2021-06-24
Development of new compositions for dust control in the mining and mineral transportation industry
Dust control in summer and winter periods is a topical problem associated with conducting open pit mining operations; however, at negative temperatures the additional requirements are imposed on dust suppressants. Preventive compositions are proposed, in which light and heavy gas oils, obtained from catalytic cracking and delayed coking, are used as base components. Involvement of heavy fractions allows to increase the flash point, thereby reducing the flammability of dust suppressant, improve its adhesion properties by increasing the content of polyaromatic hydrocarbons and reduce the cost of the final product. In order to improve low-temperature and adsorption properties of developed dust suppressants, heavy oil residues (cracking residue and tar) are included in their composition in various concentrations: 2-10 wt.%. Alternative compositions of dust suppressants, obtained by water emulsification of vinylated alkyd oligomer, are developed; the ability of this dispersion to form strong films on dusty surfaces is examined. The efficiency of using aqueous solution of vinylated alkyd oligomer as a summer dust suppressant is demonstrated. The results of this study include the development of new preventive compositions with improved low-temperature properties and confirmation of the theoretical part of the study by the results of performance tests on a laboratory facility.Alternative compositions of dust suppressors have been developed, which were obtained by emulsifying a vinyl alkyd oligomer (VAO) in water; the ability of this dispersion to form strong films on dusty surfaces has been studied. The efficiency of using an aqueous solution of vinyl alkyd oligomer in the summer period as a dust suppressant is shown. The results of this study are the development of new prophylactic formulations with improved low-temperature properties and confirmation of the theoretical part of the study by the results of tests of operational characteristics in a laboratory facility.
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Date submitted2020-06-10
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Date accepted2020-11-19
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Date published2021-04-26
Influence of jarosite precipitation on iron balance in heap bioleaching at Monywa copper mine
Ferric iron is an important oxidant in sulfide ore bioleaching. However, recirculating leach liquors leads to excess iron accumulation, which interferes with leaching kinetics and downstream metal recovery. We developed a method for controlling iron precipitation as jarosite to reduce excess iron in heap bioleaching at Monywa copper mine. Jarosite precipitation was first simulated and then confirmed using batch column tests. From the simulations, the minimum pH values for precipitation of potassium jarosite, hydronium jarosite, and natrojarosite at 25 °C are 1.4, 1.6, and 2.7, respectively; the minimum concentrations of potassium, sulfate, ferric, and sodium ions are 1 mM, 0.54, 1.1, and 3.2 M, respectively, at 25 °C and pH 1.23. Column tests indicate that potassium jarosite precipitation is preferential over natrojarosite. Moreover, decreased acidity (from 12 to 8 g/L), increased temperature (from 30 to 60 °C), and increased potassium ion concentration (from 0 to 5 g/L) increase jarosite precipitation efficiency by 10, 5, and 6 times, respectively. Jarosite precipitation is optimized by increasing the irrigating solution pH to 1.6. This approach is expected to reduce the operating cost of heap bioleaching by minimizing the chemicals needed for neutralization, avoiding the need for tailing pond construction, and increasing copper recovery.
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Date submitted2019-07-10
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Date accepted2019-08-30
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Date published2019-12-24
Methodology for calculating technical efficiency of power sections in small-sized screw downhole motors for the «Perfobur» system
With an increase in the share of old and low-yield wells and for the efficient exploitation of fields, it is necessary to include low-capacity formations into production. There are many wells where sidetracking and hydraulic fracturing are difficult due to the close proximity of the gas cap and underlying water caused by geological and technological reasons, and the use of existing secondary drilling-in technologies is not effective due to the extensive colmatated zone or annular circulation. Relevance of radial drilling technologies is growing, which allows drilling-in of the formation with a network of extended channels to establish high-quality hydraulic communication between the formation and the well without affecting the permeability of the formation. In contrast to radial drilling technologies using hydraulic washing, technical system (TS) «Perfobur» uses small-sized screw downhole motors (SDM) and rock cutting tools for channel construction. For efficient milling of production casing and destruction of rock, the hydraulic downhole motor must have high torque, and for the possibility of drilling with a high rate of angle gain, it must have short power section. Existing Russian and foreign SDM have limited number of standard sizes and do not meet the requirements specified for the development of the downhole module of TS «Perfobur». The paper discusses the development of universal small-sized sectional screw downhole motors for milling casing strings and drilling a network of branched channels of super-small diameter and radius of curvature as a part of the TS «Perfobur». Methodology proposed in the article for selecting optimal configuration of the SDM power sections allows constructing small-sized sectional downhole motor that meets the technical requirements and has improved characteristics compared to standard SDM.
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Date submitted2019-06-29
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Date accepted2019-08-25
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Date published2019-12-24
New technical solutions for ventilation in deep quarries
- Authors:
- S. G. Shakhrai
- G. S. Kurchin
- A. G. Sorokin
The paper discusses the issues of ventilating in deep quarries caused by the intensification of blasting operations at great depths, the increased distance of ore truck transportation to the daylight area, constant change in the geometrical parameters of the quarry, its microrelief and direction of mining, and increased isolation of the mined space from the environment. We provide a brief analysis of the current tools for forced airflow in deep quarries, which showed that the use of forced ventilation is often challenging since it leads to high energy consumption, high level of noise exceeding the permissible parameters, and high speeds of forced air flows may blow the dust off the quarry surfaces. The article presents methods and tools developed at the Siberian Federal University for intensifying the natural airflow in deep quarries by changing the air density at the entrance and exit points of the pit, as well as heating the shady areas using mirrors and solar energy, which do not interfere with mining and blasting operations.
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Date submitted2019-04-27
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Date accepted2019-07-10
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Date published2019-10-23
Estimation of Rock Mass Strength in Open-Pit Mining
The paper presents results of an experimental study on strength characteristics of the rock mass as applied to the assessment of open-pit slope stability. Formulas have been obtained that describe a correlation between ultimate and residual strength of rock samples and residual shear strength along the weakening surface. A new method has been developed to calculate residual interface strength of the rock mass basing on data from the examination of small-scale monolith samples with opposing spherical indentors. A method has been proposed to estimate strength characteristics (structural weakening coefficients and internal friction angles) of the fractured near-slope rock mass. The method relies on test data from shattering small-scale monolith samples with spherical indentors, taking into ac- count contact conditions along the weakening surface, and can be applied in the field conditions. It is acceptable to use irregular-shaped samples in thetests.
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Date submitted2019-02-28
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Date accepted2019-05-24
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Date published2019-08-23
Methodological Approach to Substantiation of Capital Investments of Gold Fields Based on Unit Costs
- Authors:
- A. Yu. Zaitsev
Issues of assessing capital expenditures for setting mineral deposits into operation are considered. Existing methods have a number of advantages and disadvantages, but they are determined separately for each type of fixed assets of the field. A simple method, that allows to quickly and easily determine the amount of capital costs for setting gold deposit into operation, based on data on ore reserves, as well as unit costs, taking into account the degree of infrastructure development at the deposit, is proposed. Presented methodology allows one to determine the real amount of initial capital expenditures of a gold deposit, calculate their marginal (recommended) value, and also assess the balance of capital investments in the development of a particular deposit, taking into account the existing one in the company's investment portfolio. The methodology is based on analysis of empirical material, which used real capital costs for development of gold deposits (and foreign-metal impurities) by Polymetal International plc. As a result of a statistical study, method for determining the marginal cost of a field is obtained.
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Date submitted2018-11-10
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Date accepted2019-01-17
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Date published2019-04-23
AMT soundings in the dead band within the Chukotka region (Russian Far East)
The article analyzes the amplitude spectra of audio magnetotelluric sounding (AMTs) data. Particular attention is focused on the frequency range from 1 to 5 kHz, which is called dead band. We analyzed the data of base stations used in the fieldwork during the summer and autumn seasons in 2013, 2014, and 2017. The area of work is located in the Chukotka Autonomous Area beyond the Arctic Circle. Previous researchers noted that a reliable signal in the dead band can only be obtained at nighttime. The authors of the article found that in Chukotka region in the daytime against the minimum signal within the dead band there is a local maximum at a frequency of 2.4 kHz. When registering a field for more than 3 hours during daytime, in most cases, it is possible to restore the frequencies of 2.2 and 2.6 kHz. These frequencies are reliable benchmarks, allowing in some cases to restore the AMT curve using the correlation between amplitude and phase. We have proposed ways to improve data quality in the dead band when measured during the daytime.
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Date submitted2018-05-14
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Date accepted2018-07-15
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Date published2018-10-24
Experience of Integrated use of gold-bearing raw material in the production of precious metals
- Authors:
- V. V. Zhmurova
- N. V. Nemchinova
With the depletion of rich gold-bearing ores, the processing started to use polymetallic ores, which, in addition to precious metals, contain other elements that could be valuable after recovery. The problem of using such ores is extremely difficult because of the high cost of recovery of associated valuable components. The paper presents the results of studies on the integrated use of extracted gold-bearing raw materials based on the example of the Berezitovoye deposit (Amurskaya oblast), they have low content of precious metals and many heavy non-ferrous metals (copper, lead). Experimental work was carried out to obtain copper by the method of cementation from solutions formed after the leaching of the impurities of gold-containing cathode deposits with hydrochloric acid. The cementing metal was iron turnings (waste products of the turning shop of the enterprise). Next, it was proposed to use cemented copper as a collector during re-melting of slags – wastes of processing of low-grade polymetallic ores containing precious metals. The authors obtained ingots of alloyed gold with gold weight fraction of 16 %, which meets the requirements of TU 117-2-7-75 on the content of non-ferrous metals. During hydrochloric acid treatment of cathodic deposits silver partially passed into the solution, it was recovered together with cemented copper and, in subsequent melting, passed into alloyed gold. Thus, the method proposed by the authors helps to reduce the content of precious metals in the «incomplete production cycle» of the gold recovery factory. The opportunity of selling the cementation copper at the enterprises specializing on manufacturing of jewels is shown; the expected economic effect at the same time amounted to more than 1.8 million rubles.
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Date submitted2018-01-15
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Date accepted2018-02-28
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Date published2018-06-22
About the role of hydrafed calcium carboaluminates in improving the technology of complex processing of nephelines
- Authors:
- V. M. Sizyakov
- V. N. Brichkin
The scientific justification and development of the method for industrial synthesis of complex aluminates of alkaline earth metals is an innovative solution that determined several directions in the development of technology for complex processing of nepheline raw materials. It ensures the production of high-quality metallurgical alumina, the effective utilization of nepheline sludge and production of new types of multipurpose by-products. The modern development of these technical solutions is associated with ensuring the energy efficiency of the synthesis of hydrafed calcium carboaluminates (HCCA) and increasing the level of purification of aluminate solutions. The conditions for synthesizing HCCA with the use of calcareous materials of natural and technogenic origin have been experimentally determined, which makes it possible to isolate the average particle diameter as one of the determining factors of this process. The effect of the turnover of the hydrogarnet sludge on the removal of kinetic limitations in the process of deep desalination of aluminous solutions is theoretically justified. The conditions of a two-stage dosage of HCCA are experimentally determined. It is shown that the optimum ratio of the amount of the reagent supplied in the first and second stages is about 3: 2. At the same time, the maximum degree of precipitation of silica provides the production of aluminate solutions with a silicon module at the level of 95,000, which is achieved by using a HCCA synthesized based on chemically precipitated calcium carbonate in the processing of wastes from the production of mineral fertilizers.
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Date submitted2016-11-18
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Date accepted2016-12-28
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Date published2017-04-14
Frequency electromagnetic sounding with industrial power lines on Karelia-Kola geotraverse
The paper describes theory, method and first experimental results of research on the interaction between electromagnetic waves of extremely low and ultra low frequency (0.1-200 Hz), the Earth crust and ionosphere in the field of two mutually orthogonal industrial power lines, 109 and 120 km long, in the course of FENICS experiment (Fennoscandian Electrical conductivity from Natural and Induction Control Source soundings). The main focus was on the observation results along the line of Karelia-Kola geotraverse over a distance of 700 km from the source. High horizontal homogeneity of geoelectrical lithosphere section has been detected in the eastern part of the Baltic shield at depth range from 10-15 to 50-70 km. Parameters of «regular» lithosphere section have been specified to the depth of 60-70 km. As a result of inverse problem solution for the western part of Karelia and Central Finland, a zone of decreased transverse resistivity has been detected at the depth of 50-60 km, corresponding to the area, detected by seismic methods, where Moho boundary reaches the same depth.
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Date submitted2016-09-04
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Date accepted2016-11-14
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Date published2017-02-22
Methodology of reducing rock bump hazard during room and rillar mining of North Ural deep bauxite deposits
- Authors:
- D. V. Sidorov
The article describes practical experience of using room and pillar mining (RAPM) under conditions of deep horizons and dynamic overburden pressure. It was identified that methods of rock pressure control efficient at high horizons do not meet safety requirements when working at existing depths, that is explained by changes in geodynamic processes during mining. With deeper depth, the geodynamic processes become more intensive and number of pillar and roof failures increase. When working at 800 m the breakage of mine structures became massive and unpredictable, which paused a question of development and implementation of tools for compliance assessment of used elements of RAPM and mining, geological, technical and geodynamic conditions of North Ural bauxite deposits and further development of guidelines for safe mining under conditions of deep horizons and dynamic rock pressure. It describes reasons of mine structure failures in workings depending on natural and man-caused factors, determines possible hazards and objects of geomechanic support. It also includes compliance assessment of tools used for calculations of RAPM structures, forecast and measures for rock tectonic bursts at mines of OAO “Sevuralboksitruda” (SUBR). It describes modernization and development of new geomechanic support of RAPM considering natural and technogenic hazards. The article presents results of experimental testing of new parameters of RAPM construction elements of SUBR mines. It has data on industrial implementation of developed regulatory and guideline documents at these mines for identification of valid parameters of RAPM elements at deep depths.
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Date submitted2015-12-21
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Date accepted2016-02-19
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Date published2016-12-23
Composition, age and tectonic meaning of granite boulders in the devonian conglomerates of the north-west part of Spitzbergen
- Authors:
- A. N. Sirotkin
- A. N. Evdokimov
Identifying complexes of the early Proterozoic age in the composition of crystal foundation is a key task in studying pre-Cambrian formations of the whole of Spitzbergen and its northwestern part in particular. The territory of that region is formed by three deeply metamorphosed complexes that underwent the processes of migmatization and granitization in mid-Rifey and were broken through by granitoids of mid-Rifey and mid-Paleozoic. In their turn, the outbursts of the foundation are overlayed by terrigene rocks of the Devonian graben of Spitzbergen, conglomerates forming a large share among them. In the course of petrographic and chemical studies of such compositions, as well as isotopic characteristics of zircons from the boulders of basal conglomerates of Red Bay (D 1 ) series, the suite of Wolfberget at Cape Conglomeratodden the presence was identified of reddish (meat-red) granites of isotopic age of 1631±19 Mil years, which is comparable to late Karelian processes manifested actively across the archipelago. It is also proven that transformations of these rocks within the range of 380±42 Mil years are well associated with mid-paleozoic events, considerable restructuring of the foundation associated with them. The age range we defined is another proof of manifestation of early pre-Cambrian (late Karelian) processes in the northwestern Spitzbergen.