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Date submitted2023-11-02
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Date accepted2024-09-24
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Date published2025-02-12
Mercury contamination of sediments at Indonesia Ciujung watershed: contribution of artisanal small-scale gold mining
Artisanal small-scale gold mining is the largest artificial source of mercury pollution and has been a very common problem recently. This study examined the contribution of Hg release due to artisanal small-scale gold mining in contaminating the sediment of the watershed in Indonesia. Different from other methods, we measured Hg pollution using the stable isotopes of carbon and nitrogen. This report is the first time analytical reports in Indonesia since most papers focus primarily on only detecting heavy metals in river water and sediments, neglecting deep research on Hg pollution and resources. The findings of this study indicate that artisanal and small-scale gold mining activities, located in the upstream areas of the tributaries that act as point sources, are the primary source of mercury in the sediment of the Ciujung watershed. The isotopes δ13C and δ15N successfully trace the Hg-contaminated sediment in the Ciujung watershed derived from the Cisimeut and Ciberang Rivers based on soil organic matter. The biological effect showed the Hg concentration in most of the sampling sites exceeded the Effects-range medium and Probable effect limit values. The Risk quotient values of Hg indicated the Hg pollution had a possibility effect on the benthic organism. Several limitations have also been added in this study and needs for further investigation.
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Date submitted2024-04-11
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Date accepted2024-11-07
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Date published2025-01-17
Thyristor booster device for voltage fluctuation reduction in power supply systems of ore mining enterprises
The article is devoted to solving the problem of voltage fluctuations in the power supply systems of ore mining enterprises. The connection of high-power consumers with abruptly variable operating mode (for example, high-voltage mining excavators) causes voltage fluctuations and sags, disabling electrical equipment, communication, and automation devices in the 6-10 kV distribution network, which disrupts technological processes, etc. The use of existing solutions and methods to reduce voltage variations caused by dynamic loads is not effective. To solve the problem, booster transformers with high-speed thyristor switches can be used to work out switching the control steps towards increasing or decreasing the voltage. The authors offer a new circuitry solution for a thyristor booster device (TBD) with a pulse-phase control method. The purpose of the research is to determine the control laws of TBD, which enable to effectively reduce voltage fluctuations from dynamic load in the power supply systems of mining enterprises. The article provides a schematic diagram of the TBD and describes the principle of operation of the device. Some modes of increasing and decreasing the output voltage of the TBD, as well as the basic mode (without voltage addition) are provided. Mathematical modeling of TBD control processes was carried out and adjustment characteristics were set taking into account the load power factor. On a simulation computer model of a 6 kV electric network with a dynamic load, the verification of the adjustment characteristics of TBD obtained during mathematical modeling was carried out. Based on the research results, the laws for regulating the output voltage of TBD were established. The TBD effective control range with normal permissible limits of odd harmonics have been determined. The conducted research will make it possible to implement the device control system.
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Date submitted2023-11-10
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Date accepted2024-06-03
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Date published2025-02-25
Enhancing the interpretability of electricity consumption forecasting models for mining enterprises using SHapley Additive exPlanations
- Authors:
- Pavel V. Matrenin
- Alina I. Stepanova
The objective of this study is to enhance user trust in electricity consumption forecasting systems for mining enterprises by applying explainable artificial intelligence methods that provide not only forecasts but also their justifications. The research object comprises a complex of mines and ore processing plants of a company purchasing electricity on the wholesale electricity and power market. Hourly electricity consumption data for two years, schedules of planned repairs and equipment shutdowns, and meteorological data were utilized. Ensemble decision trees were applied for time series forecasting, and an analysis of the impact of various factors on forecasting accuracy was conducted. An algorithm for interpreting forecast results using the SHapley Additive exPlanation method was proposed. The mean absolute percentage error was 7.84 % with consideration of meteorological factors, 7.41 % with consideration of meteorological factors and a load plan formulated by an expert, and the expert's forecast error was 9.85 %. The results indicate that the increased accuracy of electricity consumption forecasting, considering additional factors, further improves when combining machine learning methods with expert evaluation. The development of such a system is only feasible using explainable artificial intelligence models.
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Date submitted2023-07-05
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Date accepted2024-06-03
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Date published2024-12-25
Complete extraction of conditioned ores from complex-structured blocks due to partial admixture of substandard ores
- Authors:
- Bayan R. Rakishev
The paper presents mining-technological substantiation of complete extraction of conditioned ores from complex-structured blocks of benches by mixing a layer of substandard ores of certain sizes. The relevance of the work consists in the development of innovative methods of establishing the parameters of the substandard layer of ores to be added to the conditioned ores. The main problem is to ensure complete extraction of useful components into concentrate from shipped ore with acceptable deviations from the required ones. A new typification of complex-structured ore blocks of the bench has been carried out. Analytical dependences of mining and geological characteristics of complex-structured ore blocks were obtained. Theoretical dependences for determining the main indicators of mineral processing are derived. Analytical dependences for determination of the content of useful component in shipped ore α' – mixture of conditioned ore with the content of useful component α and admixed layer of substandard ore with the content of useful component α'' are offered. For the first time in mining science, a new approach of complete extraction of conditioned ores from complex-structured blocks of benches by grabbing a certain part of substandard ores during excavation, increasing the volume of extracted ore and expanding the extraction of useful components in the concentrate has been substantiated. The increment of useful components can reach 10-15 % of the total volume of extraction, which allows predicting a significant increase in the completeness of mineral extraction from the Earth's interior.
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Date submitted2023-06-01
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Date accepted2024-03-05
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Date published2024-08-26
Analyzing friction bolts load bearing capacity in varying rock masses: an experimental study in Anti Atlas Imiter silver mining region, Morocco
This study analyzes how key factors impact friction rock bolt capacity using standard pull-out tests, focusing on 39 mm diameter, 180 cm long split-tube bolts. We investigate bolt performance dependence on rock mass rating (RMR), time after installation, schistosity orientation, surface roughness, and installation quality. The aim is optimizing bolt design and implementation for enhanced underground stability and safety. Results show RMR strongly exponentially correlates with pull-out resistance; higher quality rock masses increase capacity. Anchorage capacity significantly rises over time, especially for RMR above 70. Increasing angle between bolt axis and rock foliation from 0 to 90° boosts pull-out response. Reducing borehole diameter below bolt diameter grows bolt-ground friction. Empirical models estimate load capacity based on RMR, time, orientation, diameter, roughness and installation quality. These reliably predict bolt performance from site conditions, significantly improving on basic RMR methods. Experiments provide practical friction bolt behavior insights for typical rock masses. The data-driven analysis ensures models are applicable to actual underground scenarios. This enables tailored optimization of bolting configurations and supports. Methodologies presented should improve safety, efficiency and cost-effectiveness of reinforced mining and tunneling. Overall, this study fundamentally furthers friction bolt performance understanding, enabling superior underground support design.
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Date submitted2023-09-29
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Date accepted2023-10-25
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Date published2024-08-26
Laboratory studies of transformation of porosity and permeability and chemical composition of terrigenous reservoir rocks at exposure to hydrogen (using the example of the Bobrikovskii formations in the oil field in the northeast Volga-Ural oil and gas province)
The article describes the methodology for laboratory studies of reservoir rock exposure to hydrogen. The stages of sample research and the instruments used in the experiments are considered. A comparative analysis of the results of studies on porosity and permeability of core samples was performed. It was shown that after exposure to hydrogen, the porosity decreased by 4.6 %, and the permeability by 7.9 %. The analysis of correlation dependencies demonstrated a typical change in the relationship of these characteristics: after the samples exposure to hydrogen the scatter of the values increased and the correlation coefficient decreased, which indicates a change in the structure of the void space. Based on the research results, it was concluded that the decrease in porosity and permeability of the core samples occurred due to their minor compaction under the action of effective stresses. The chemical analysis of the rock showed no major difference in the composition of the basic oxides before and after exposure to hydrogen, which points to the chemical resistance of the studied formation to hydrogen. The experimental results showed that the horizon under consideration can be a storage of the hydrogen-methane mixture.
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Date submitted2023-07-27
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Date accepted2024-06-03
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Date published2024-12-25
Normalized impulse response testing in underground constructions monitoring
Impulse Response testing is a widespread geophysical technique of monolithic plate-like structures (foundation slabs, tunnel lining, and supports for vertical, inclined and horizontal mine shafts, retaining walls) contact state and grouting quality evaluation. Novel approach to data processing based on normalized response attributes analysis is presented. It is proposed to use the energy of the normalized signal calculated in the time domain and the normalized spectrum area and the average-weighted frequency calculated in the frequency domain as informative parameters of the signal. The proposed technique allows users a rapid and robust evaluation of underground structure’s grouting or contact state quality. The advantage of this approach is the possibility of using geophysical equipment designed for low strain impact testing of piles length and integrity to collect data. Experimental study has been carried out on the application of the technique in examining a tunnel lining physical model with a known position of the loose contact area. As examples of the application of the methodology, the results of the several monolitic structures of operating municipal and transport infrastructure underground structures survey are presented. The applicability of the technique for examining the grouting of the tunnel lining and the control of injection under the foundation slabs is confirmed. For data interpretation the modified three-sigma criteria and the joint analysis of the attribute’s behavior were successfully used. The features of the field work methodology, data collection and analysis are discussed in detail. Approaches to the techniques' development and its application in the framework of underground constructions monitoring are outlined. The issues arising during acoustic examination of reinforced concrete plate-like structures are outlined.
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Date submitted2023-08-02
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Date accepted2023-12-27
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Date published2024-04-25
Justification of the approaches to improve management strategy of the mining system based on the analysis of data on the mining of complex structural rock blocks
Long-term activity of mining enterprises causes the necessity to substantiate the strategies of management of the mining and technical system functioning in terms of improvement of ore quality control, which is determined by its change in the course of field development due to the priority development of the main reserves and, as a consequence, forced transition to the mining of complex structural rock blocks with a decrease in the recovery percentage, which is typical in case the ore component meets the requirements of the feasibility study in terms of grade at substandard capacity. In this case, it is possible to identify the recovery percentage and the potential for its increase by analyzing the long-term activity of the mining and industrial enterprise, namely, by analyzing the data of mining complex structural rock blocks with the subsequent establishment of the relationship between the primary data on mining and geological conditions and information on the quality of the mineral obtained from the technological equipment. Therefore, the purpose of the research was to substantiate the necessity of improving the management strategy of the mining-technical system functioning, which consists in the fact that on the basis of analyzing the mining data of complex structural rock blocks it is possible to determine the ore mass losses and their quantity and to lay the basis for the development of decisions on its extraction. For this purpose, the collected data on the mining of complex structural rock blocks, accounting the geological and industrial type of extracted ores, were considered in modeling the conditions and studying the parameters of technological processes, the implementation of which provides additional products. It was revealed that the ore mass from substandard thickness layers is delivered to the dumps, and ore mass losses have been estimated at 25-40 % per year. It is proved that determination of ore mass losses based on the analysis of data on mining of complex structural rock blocks, as well as timely solution of this issue can significantly increase the production efficiency of mining and technical system. Taking into account for the results obtained, the options for optimizing the production of the mining and engineering system were proposed.
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Date submitted2022-10-29
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Date accepted2023-10-25
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Date published2024-04-25
Assessment of rock massif sustainability in the area of the underground research laboratory (Nizhnekanskii Massif, Enisei site)
The study presents the results of the research on geodynamic and geological conditions of the Enisei site (Krasnoyarsk Krai), chosen for the construction of an underground research laboratory. The laboratory is being built at a depth of 500 m to assess the suitability of the rock mass for burying high-level radioactive waste. The rocks consist of weakly fractured gneisses, granites, and dikes of metadolerites. Field observations were conducted on bedrock outcrops. They included the determination of rock mass quality indicators, measurement of rock fracturing, and a rating classification of stability using N.Barton's method. GNSS observations were also made to monitor surface deformations. These data were used to develop a three-dimensional structural model, including lithology, fault disruptions, intrusive bodies, elastic-strength properties of rocks, and the sizes of zones influenced by faulting. It will serve as a basis for boundary conditions and the construction of three-dimensional variational models of stress-strain states, identifying zones of concentration of hazardous stresses, and planning in situ geomechanical experiments in underground mines of the laboratory. The obtained values of the modified QR index for the main types of rocks allowed their classification as stable and moderately stable, corresponding to strong and very strong rocks on Barton's scale and the massif rating according to geomechanical classification.
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Date submitted2023-07-07
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Date accepted2023-09-20
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Date published2024-02-29
Isotherm and kinetic adsorption of rice husk particles as a model adsorbent for solving issues in the sustainable gold mining environment from mercury leaching
One of the techniques used in extracting gold in small-scale gold mining is mercury amalgamation. However, the use of mercury presents significant health and environmental hazards, as well as suboptimal efficiency in gold extraction. This study explores the possibility of the use of rice husk as a prototype adsorbent for mercury removal from its leaching in mining environments. To support the analysis, the rice husk adsorbent was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, electron dispersive X-ray spectroscopy, atomic absorption spectrophotometers and Brunauer − Emmett − Teller analysis. To investigate the removal of Hg from aqueous solutions, batch adsorption experiments were conducted, and the efficiency was optimized under various parameters such as contact time, rice husk dosage, and initial concentration of mercury. Kinetic and isotherm investigations were also carried out to gain a better understanding of the adsorption properties. The kinetic adsorption was analyzed using the pseudo-first-order and pseudo-second-order. Furthermore, the isotherm adsorption was analyzed using ten adsorption isotherm models (i.e., Langmuir, Freundlich, Temkin, Dubinin – Radushkevich, Flory – Huggins, Fowler – Guggenheim, Hill – de Boer, Jovanovic, Harkin – Jura, and Halsey). The amount of mercury absorption increased with increasing contact time, adsorbent mass, and initial concentration of mercury. The pseudo-second-order kinetic model is the best model that can be applied to describe the adsorption process. Analysis of the adsorption results obtained shows that the adsorption pattern is explained through the formation of a monolayer without any lateral interaction between the adsorbate and adsorbent. In addition, the formation of multilayers due to inhomogeneous pore distribution also occurs which causes a pore filling mechanism. We found that the isotherm phenomena are near the Jovanovic models with the maximum adsorption capacity) of rice husk found to be 107.299 mg/g. As a result, rice husk could be a promising option for wastewater treatment due to its fast and efficient removal capacity, as well as its affordability and eco-friendliness. The predicted thermodynamic studies using the Flory – Huggins isotherm model show that the adsorption process is endothermic, spontaneous, and physisorption. The impact shows that the utilization of rice husk can be used and fit for the current issues in the sustainable development goals (SDGs).
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Date submitted2023-08-16
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Date accepted2023-10-25
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Date published2023-10-27
250 years in the service of the Fatherland: Empress Catherine II Saint Petersburg Mining University in facts and figures
In 2023, Empress Catherine II Saint Petersburg Mining University – the first higher technical educational institution in Russia – turns 250 years. Any significant anniversary is an occasion to look back, analyze and evaluate the way traveled. The article analyzes the main achievements of the Mining University on the basis of statistical material from the moment of the foundation of the Mining School to the present day: educational and pedagogical experience in the education and training of mining specialists, scientific and technical intelligentsia; the outstanding contribution of its scientists, graduates to the establishment and development of the mineral resource complex of Russia, in strengthening the country's defense power, the creation of scientific schools. The first part of the article provides data on the number of graduates for different periods of the history of the university, shows the dynamics of their number growth, the peculiarities of learning. According to the authors, over 250 years, about 99 thousand engineers and mining specialists have been prepared in the university. The second part of the article is devoted to the characteristics of the teaching staff, in which a special place is occupied by his favorites, who have become outstanding scientists, academicians and corresponding members of the Academies of Sciences. Those of them who have devoted more than a dozen years of their lives to teaching within the walls of the university are noted. The final part shows the main scientific achievements of the university: the organization of scientific societies, the development of scientific schools, research institutes, etc. About 200 graduates of the Mining University have been awarded State Prizes for their contribution to the development of science and technology. The work of dissertation councils was noted, in which more than 5 thousand dissertations have been defended since 1943.
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Date submitted2022-05-20
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Date accepted2023-06-20
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Date published2024-02-29
Increasing the quality of zeolite-bearing rocks from Eastern Transbaikalia by applying directed energy
This paper presents the use of accelerated electrons to treat zeolite-bearing rocks from Eastern Transbaikalia to increase the efficiency of separating zeolites from rock-forming minerals via electromagnetic separation. The effectiveness of the liberation of zeolite minerals using accelerated electrons was analyzed. The results of dry electromagnetic separation of zeolite-bearing rocks are presented. The dependence of the extraction of iron-bearing minerals from zeolite-bearing rocks by electromagnetic separation on the magnetic field intensity for different particle sizes has been established. The main methods of zeolite-bearing rock enrichment and ore preparation were determined. A technological scheme for processing zeolite-bearing rocks, based on the use of accelerated electron treatment at the ore preparation stage, is presented, significantly improving the zeolite production quality.
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Date submitted2022-10-13
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Date accepted2023-10-11
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Date published2023-10-27
An innovative approach to injury prevention in mining companies through human factor management
This study argues that human error has an effect on occupational injury risks in mining companies. It shows through an analysis of existing approaches to occupational risk assessment that it is necessary to develop a quantitative assessment method factoring in individual psychophysiological attributes in order to analyze injury risks posed to miners. The article presents the results of a comprehensive analysis of how workers’ psychophysiological attributes influence their susceptibility to occupational injuries in underground mining conditions. By utilizing statistical data processing methods, such as discriminant and regression analysis, the study develops models to forecast personal injury risks among miners. These quantitative models underlie the proposed method for assessing miners’ susceptibility to injuries. The study outlines an algorithm for the practical application of this method and shows how the method was validated using a training sample. It provides recommendations for managing the human factor, incorporating the results of the proposed method, and emphasizes the importance of implementing a series of protective measures to mitigate the risk of occupational injuries in underground mining operations.
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Date submitted2023-04-23
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Date accepted2023-10-24
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Date published2023-10-27
Mining Museum as a space of science and education in Mining University
An interdisciplinary investigation is presented focusing on the study of the Mining Museum collections in relation to research, educational and social practices. Natural science and artistic exhibits are considered. The authors made an attempt to determine the significance of the mineralogical collection based on the criteria proposed by I.V.Pekov. For the first time, general statistics on the new minerals in the mineralogical museums of the USSR was collected in 1988; in subsequent years, such information was not published. Collection of the Mining Museum comprises mineral species received after 1988 and having the status of holotypes, neotypes, and cotypes. In anticipation of the 250th anniversary of Saint Petersburg Mining University its special contribution to the progress of science was noted; the merits of scientists were immortalized in the names of minerals stored in the Mining Museum collection. An important role of the Museum in recording and representation of achievements of the Mining University is shown. The authors present the Mining Museum as a special educational space where an objective image of the world is created shaped by the scientific and humanitarian environment. The Museum is regarded as a space for forming the professional identity, important for the successful work of future University graduates. The interior of the Mining Museum designed and created in the 1st half of the XIX century taking into account the ideas about the succession of scientists from different epochs, respect for scientific traditions of antiquity and achievements in the field of studying the world plays a significant role in this process. Images of thinkers of the antiquity in the interiors of the educational and public spaces of the XIX century made it possible to emphasize the importance of cultural correlation with ideas of the Enlightenment. Specific examples from the collection show how the Mining Museum was implementing the scientific and educational goals of the Mining University throughout its history.
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Date submitted2021-05-12
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Date accepted2022-05-11
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Date published2023-07-19
Application of the cybernetic approach to price-dependent demand response for underground mining enterprise electricity consumption
The article considers a cybernetic model for the price-dependent demand response (DR) consumed by an underground mining enterprise (UGME), in particular, the main fan unit (MFU). A scheme of the model for managing the energy consumption of a MFU in the DR mode and the implementation of the cybernetic approach to the DR based on the IoT platform are proposed. The main functional requirements and the algorithm of the platform operation are described, the interaction of the platform with the UGME digital model simulator, on which the processes associated with the implementation of the technological process of ventilation and electricity demand response will be simulated in advance, is shown. The results of modeling the reduction in the load on the MFU of a mining enterprise for the day ahead are given. The presented solution makes it possible to determine in advance the necessary power consumption for the operation of the main power supply unit, manage its operation in an energy-saving mode and take into account the predicted changes in the planned one (e.g., when men hoisting along an air shaft) and unscheduled (e.g., when changing outdoor air parameters) modes. The results of the study can be used to reduce the cost of UGME without compromising the safety of technological processes, both through the implementation of energy-saving technical, technological or other measures, and with the participation of enterprises in the DR market. The proposed model ensures a guaranteed receipt of financial compensation for the UGME due to a reasonable change in the power consumption profile of the MFU during the hours of high demand for electricity, set by the system operator of the Unified Energy System.
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Date submitted2023-03-14
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Date accepted2023-06-20
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Date published2023-07-19
The wireless charging system for mining electric locomotives
The electric vehicles development has a high potential for energy saving: an energy-saving traffic control can reduce energy resource consumption, and integration with the power grid provides the ability of daily load pattern adjustment. These features are also relevant for underground mining. The critical element of vehicle-to-grid integration is the charging infrastructure, where wireless charging is promising to develop. The implementation of such systems in underground mining is associated with energy efficiency issues and explosion safety. The article discusses the development and research of a wireless charging system for mining electric locomotive A-5.5-600-U5. The analytic hierarchy process is used for justification of the circuitry and design solution by a comparison of different technical solutions based on energy efficiency and safety criteria. A complex computer model of the wireless charging system has been developed that gives the transients in the electrical circuit of a wireless charging system and the high-frequency field density distribution near the transmitting and receiving coils in a 3D setting. An approach to ignition risk evaluation based on the analysis of high-frequency field density in the charging area between the coils of the wireless charging system is proposed. The approach using a complex computer model is applied to the developed system. The study showed that the wireless charging system for mining electric locomotives operating in the gaseous-and-dusty mine is technically feasible and there are designs in which it is explosion safe.
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Date submitted2023-01-12
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Date accepted2023-06-20
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Date published2023-07-19
Improvement of energy efficiency of ore-thermal furnaces in smelting of alumosilicic raw materials
The issues of energy saving in pyrometallurgical production during processing of mineral raw materials in ore-thermal furnaces are particularly important for the development of new energy-efficient technologies. The reduction of the specific power consumption during melting at different stages of heating and melting of charge materials when modeling is related to obtaining kinetic curves in the process of kyanite concentrate regeneration in polythermal conditions. Based on practical data of carbo-thermal reduction the mathematical modeling of reduction processes from alumosilicic raw materials – kyanite was carried out. In this work, the nonisothermal method based on a constant rate of charge heating (i.e. a linear dependence between time and temperature) was used for the reduction of kyanite charge, which saves electrical energy. The experiments were carried out on a high-temperature unit with a heater placed in a carbon-graphite crucible. Based on the obtained kinetic dependences of nonisothermal heating of enriched kyanite concentrates in plasma heating conditions we obtained a number of kinetic anamorphoses of the linear form which point to the possibility of describing the reaction rate using the modified Kolmogorov – Erofeev equation for given heating conditions and within a narrow temperature range. The complex of mathematical modeling makes it possible to create a control algorithm of technological process of reduction of kyanite concentrate to a metallized state within the specified temperature range for the full flow of reaction exchange and to reduce the specific power consumption by 15-20 %. With the help of the received kinetic dependences, taking into account the thermodynamics of processes and current state of the art it is possible to create a universal thermal unit for the optimal carbothermal reduction of charge to a metallized state (alloy) with minimum power inputs compared to existing technologies.
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Date submitted2023-03-16
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Date accepted2023-06-20
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Date published2023-07-19
Evaluation of the influence of the hydraulic fluid temperature on power loss of the mining hydraulic excavator
In the steady state of operation, the temperature of a mining excavator hydraulic fluid is determined by the ambient temperature, hydraulic system design, and power losses. The amount of the hydraulic system power loss depends on the hydraulic fluid physical and thermodynamic properties and the degree of wear of the mining excavator hydraulic system working elements. The main causes of power losses are pressure losses in pipelines, valves and fittings, and leaks in pumps and hydraulic motors. With an increase in the temperature of hydraulic fluid, its viscosity decreases, which leads, on the one hand, to a decrease in power losses due to pressure losses in pipelines, valves and fittings, and, on the other hand, to an increase in volumetric leaks and associated power losses. To numerically determine the level of power losses occurring in the hydraulic system on an example of the Komatsu PC750-7 mining excavator when using Shell Tellus S2 V 22, 32, 46, 68 hydraulic oils with the corresponding kinematic viscosity of 22, 32, 46, 68 cSt at 40 °C, the developed calculation technique and software algorithm in the MatLab Simulink environment was used. The power loss coefficient, obtained by comparing power losses at the optimum temperature for a given hydraulic system in the conditions under consideration with the actual ones is proposed. The use of the coefficient will make it possible to reasonably select hydraulic fluids and set the values of the main pumps limit state and other hydraulic system elements, and evaluate the actual energy efficiency of the mining hydraulic excavator. Calculations have shown that the implementation of measures that ensure operation in the interval with a deviation of 10 % from the optimal temperature value for these conditions makes it possible to reduce energy losses from 3 to 12 %.
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Date submitted2023-03-14
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Date accepted2023-06-20
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Date published2023-07-19
A reliability study of the traction drive system in haul trucks based on failure analysis of their functional parts
The efficiency of a mining and processing plant depends on the level of complex mechanization of the production process. In mineral extraction, haulage is a major cost category, with haul trucks being the key component of the mining transportation system. To improve production performance, mining operations can increase their haulage turnover and reduce transportation costs, which necessitates making haul trucks more reliable. This can be done by improving their mean time to first failure (MTFF) indicators. This article analyzes the reliability status of the traction drive system inhaul trucks operating in the mineral resources sector. It provides a quantitative assessment of traction drive system failures resulting from part defects and discusses the associated repair costs. By examining failure data from 2018 to 2022 and the results of vibration tests performed on a diesel generator, the study reveals that the most expensive failures are associated with defects in the synchronous generator, which are primarily caused by elevated external vibrations. Based on basic vibration tests and vibration spectra tests at different operating modes, recommendations have been formulated concerning the generator’s robustness to external mechanical forces and the ways to increase the generator’s protection grade to prevent dust intrusion. The study also identifies the frequency range that poses the greatest risk of damage to the windings.
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Date submitted2022-04-03
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Date accepted2023-03-02
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Date published2023-12-25
Specifics of geotechnical risk control in the design of underground structures
The underground space development is associated with the emergence of complex and dangerous situations, often leading to accidents. The condition for their development is the potential geotechnical risks. High-quality execution and analysis of design work at all the stages of design, starting from the early stages, is one of the effective ways to control risks. Clarification of the characteristics and features of the rock mass adjacent to the projected underground structure makes it possible to identify the potential cause of the occurrence of an adverse event with a certain probability during the construction and operation of an underground structure. The purpose of a qualitative risk analysis is to identify risk factors in underground construction. The value of the total geotechnical risk, expressed by the sum of each of the possible risks, should be numerically estimated at the design stage of a specific underground facility. At the same time, it is extremely important to develop a methodology for managing geotechnical risks, which would make it possible to assess their probability of development at an early stage of project preparation and propose measures to reduce or prevent them. This technique is given in the article. The results of the study conducted in accordance with the presented methodology showed that geotechnical risk control proved an effective method in preventing accidents during underground construction.
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Date submitted2021-10-31
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Date accepted2023-03-02
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Date published2023-12-25
Improvement of technological schemes of mining of coal seams prone to spontaneous combustion and rock bumps
On the example of the Alardinskaya mine, the problem of underground mining of seams prone to spontaneous combustion and rock bumps in the conditions of the Kondomsky geological and economic region of the Kuznetsk coal basin is considered. The contradictions in the requirements of regulatory documents for the width of the inter-panel coal pillars in the mining of seams with longwalls in conditions of endogenous fire hazard and in the mining of seams that are dangerous due to geodynamical phenomena are discussed. These contradictions impede the safe mining of seams using traditionally used layouts with the danger of spontaneous combustion of coal and rock bumps. A mining-geomechanical model is presented, which is used for numerical three-dimensional simulation of the stress-strain state of a rock mass with various layouts for longwall panels using the finite element method. The results of the numerical analysis of the stress state of the rock mass immediately before the rock bump are presented, and the main factors that contributed to its occurrence during the mining of the seam are established. A dangerous degree of stress concentration in the coal seam near the leading diagonal entries is shown, especially in conditions of application of abutment pressure from the edge of panels’ gob. The analysis of the features of stress distribution in the inter-panel pillar at different widths is carried out. Recommendations for improving the layout for the development and mining of coal seams that are prone to spontaneous combustion and dangerous in terms of rock bumps in the conditions of Alardiskaya mine have been developed. The need for further studies of the influence of pillars for various purposes, formed during the mining of adjacent seams, on the stress-strain state of previously overmined and undermined seams is shown.
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Date submitted2022-11-04
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Date accepted2023-03-03
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Date published2023-04-25
Efficiency of acid sulphate soils reclamation in coal mining areas
During the development of coal deposits, acid mine waters flowing to the surface cause the formation of acid sulphate soils. We study the effectiveness of soil reclamation by agrochemical and geochemical methods at the site of acid mine water discharge in the Kizel Coal Basin, carried out in 2005 using alkaline waste from soda production and activated sludge. A technosol with a stable phytocenosis was detected on the reclaimed site, and soddy-podzolic soil buried under the technogenic soil layer with no vegetation on the non-reclaimed site. The buried soddy-podzolic soil retains a strong acid рН concentration Н 2 О = 3. A high content of organic matter (8-1.5 %) is caused by carbonaceous particles; the presence of sulphide minerals reaches a depth of 40 cm. Technosol has a slightly acid pH reaction H 2 O = 5.5, the content of organic matter due to the use of activated sludge is 19-65 %, the presence of sulphide minerals reaches a depth of 20-40 cm. The total iron content in the upper layers of the technosol did not change (190-200 g/kg), the excess over the background reaches 15 times. There is no contamination with heavy metals and trace elements, single elevated concentrations of Li, Se, B and V are found.
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Date submitted2022-10-17
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Date accepted2023-02-13
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Date published2023-04-25
Environmental geotechnology for low-grade ore mining with the creation of conditions for the concurrent disposal of mining waste
Due to the constantly deteriorating environmental situation in the regions with mining enterprises, the article considers the topical issue of disposing the maximum possible volume of waste from the mining and processing of low-grade ferrous ores through the creation of an effective underground environmental geotechnology. Traditional procedure with descending mining of reserves with a caving system does not allow waste to be disposed of in a gob. The idea is to use geotechnology based on the ascending order of mining the ore body, room excavation, leaving truncated pillars, and staggered arrangement of adjacent rooms in height, which makes it possible to form containers for waste disposal in the form of a cementless backfill. The main characteristics of the proposed procedure are investigated and compared with the traditional procedure of low-grade iron ores mining. It was established that from the point of view of the complete extraction of reserves and the unit costs for the preparatory-development operations, the processes are comparable, while in terms of the mining quality, the proposed option is much more efficient. Evaluation of environmental geotechnology by the criterion of waste disposal, performed according to the proposed methodology, showed that the combination of these technical solutions ensures the placement in the formed gob from 80 to 140% of all waste generated during the mining and beneficiation of low-grade iron ores.
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Date submitted2022-06-28
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Date accepted2023-01-19
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Date published2023-02-27
Influence of mining rent on the efficiency of using natural potential: the paradox of plenty and its Russian specifics
- Authors:
- Arunas A. Lapinskas
The most powerful potential of Russia's natural resources is only partially realized, and determining the reasons for the insufficient efficiency of its use is a current research topic. The exploitation of mineral resources that bring mining rent (primarily oil and gas) gives rise to the so-called “paradox of plenty” (PP), which in some cases manifests itself as a significant slowdown in economic development. The purpose of the article is to clarify the signs, degree and forms of PP manifestation and related problems (“resource curse”, “oil curse”, etc.) in the Russian economy. Since the causes of these phenomena are usually associated with rent extraction and peculiarities of the institutional structure of the economy, the works of leading economists who support the theories of “rent-oriented behavior” and the role of public institutions in the process of the PP emergence were critically analyzed. To determine the signs and degree of PP manifestation and related problems, an analysis of determining the shares of oil and gas in the structure of exports, revenues from their sale in the federal budget, and oil and gas products in the structure of GDP, was made. It is concluded that there are no sufficient grounds for ascertaining clear signs of a “rent-oriented” Russian economy and a “resource curse”; important counteracting factors that refute the unambiguous conclusions about the high degree of PP impact on the Russian economy were identified. The author's interpretation of the role of public institutions, the factors of formation and forms of PP manifestation, the specifics of differential mining rent and its role in the formation of PP are proposed; options for solving problems generated by PP – directions for improving the tax system in the field of oil and gas, etc.; substantiation of the need to develop a strategic state program for diversifying the sectoral structure of the Russian economy; directions for adjusting economic policy in the field of oil and gas industry development, etc.
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Date submitted2022-05-23
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Date accepted2022-07-21
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Date published2023-02-27
Alluvial tin mining by spray-suction borehole method: a case study on remaining alluvial tin reserves in Bangka Belitung, Indonesia
The area of the Bangka Belitung Islands, which is a potential area for alluvial tin deposits in Indonesia, has been affected by the destruction of tin reserves on the mainland due to rampant artisanal mining, which has left remnants of small-dimensional reserves. The remnants of these reserves can no longer be mined using the hydraulic mining of open pit method due to the small dimensions of the deposits. The hypothesis is that such sedimentary conditions can only be mined by the borehole method. This research aimed to design tools and perform test mining using the borehole method with a spray-suction mechanism. This research produced a novelty, namely, a method and parameters for alluvial tin deposits mining using borehole mining methods, such as the excavation capacity, excavation radius, mining recovery, and dilution factor. The benefit of this research is expected to provide an opportunity to increase the amount of onshore alluvial tin reserves to support tin production.