Mine Planning Research Articles

Slope geometry optimization considering groundwater drawdown scenarios at an open-pit phosphate mine, southeastern Brazil

The design of open-pit mines should balance safety and economy. However, safe geotechnical conditions generally involve redesigning the geometry of slopes and groundwater drawdown, significantly increasing the costs of mining operations. The use of numerical models to simulate groundwater drawdown and slope stability can be an alternative to assess cost–benefit trade-offs for decision-making. This study documents a mining plan using groundwater drawdown scenarios that illustrate how geotechnical, economic, and environmental indicators can be combined to obtain optimum slope geometry for open-pit mining. The optimization approach analyzed different scenarios of groundwater drawdown for the final pit of a phosphate mine to improve the pit slopes stability. The groundwater simulation scenarios included the combination of deep horizontal drains and pumping wells. Stability analyses using the limit equilibrium method were used to obtain the bench, inter-ramp, and overall factors of safety of different representative sections. The factors of safety obtained, the drawdown costs and the water table elevation of each section were selected as indicators for obtaining the optimal drawdown scenario using a multi-objective tool. The groundwater control system obtained with 11 horizontal drains and 1 pumping well was considered the most adequate from the geotechnical and economic perspectives. Slope geometry optimization obtained with this drawdown scenario led to adequate inter-ramp and overall safety factors for the final pit design, reducing the barren-to-ore ratio to 0.38, much less than the present ratio (≈ 3). The results are important for optimizing the slope geometry of open-pit mines and can be replicated in other regions.

Coal Mine Goaf Interpretation: Survey, Passive Electromagnetic Methods and Case Study

Coal mine goaf detection remains confronted with the lack of fast, effective and low-cost exploration means, especially for the accurate prediction of mining threats primarily caused by hydraulic infiltration. The rapid popularization of passive electromagnetic methods has contributed greatly to improving the interpretation effects of different types of goafs. This paper, firstly, summarizes the pros and cons of various exploration methods in goaf detection. Then, the feasibility of goaf detection using novel passive electromagnetic methods (e.g., the super low frequency alternating magnetic component method (SLF) and audio frequency magnetotelluric method (AMT)) is proposed and further discussed. With well-designed geo-electrical goaf models, the theoretical results demonstrate that the semi-quantitative interpretation of SLF responses can be directly used for the delineation of the target layer in the estimated depth range. In contrast, 3D inversion provides more information about conductive targets with the appropriate initial model selection. Then, shallow, low-resistive targets can be more accurately allocated in the inversion maps. Moreover, the real data interpretation results from study areas demonstrate that the SLF method can utilize the magnetic component responses to effectively identify the fault structures, and indirectly contributes to judge the goaf collapse locations in favor of describing the potential distribution of fracture water infiltration. Combined with the three-dimensional (3D) resistivity inversion of AMT data, the low-resistive water-rich areas within the depth of 400 m were revealed. The inverted depth distributions are basically consistent with those of the water-filled goafs and surrounding layers, which were also confirmed by known logging data. The detailed delineations of water-control fracture zones can be inferred to relate to aquifers in some mining areas; this can reveal potential collapses that require successive mining planning. In specific working faces, goaf risks have been handled in advance by strengthening the continuous monitoring of the water level and water inflow. The above verification has laid a theoretical and practical foundation for passive electromagnetic interpretation methods for effectively predicting collapse-type risks or hydraulic threats in coal mine goafs.

Numerical Simulation of Underground Mining-Induced Fault-Influenced Rock Movement and Its Application

The F317 fault, as a major tectonic zone in the Jianshan mine area, influences the geotectonic features and geomechanical properties of the mine area. Mining operations need to be conducted within these tectonic systems, so it is important to fully study and understand the characteristics and evolution of these tectonic systems to develop reasonable mining plans and safety measures. Aiming at the problem that the existence of the F317 fault affects the stability of the west road during the mining of the security pillar at The Jianshan underground mine in Panzhihua Iron Mine, the mechanical model of the fault surface was established through the theory of material mechanics. The mechanical criterion of fault slip during the security pillar retrieval process was obtained and combined with the contact surface theory in the numerical analysis software FLAC3D. Two numerical calculation models with and without the F317 fault were established to analyze the change characteristics of the maximum tensile stress and displacement of the road protection zone under different simulation scenarios. The influence of the fault’s presence on the surface road’s stability during the security pillar retrieval process was obtained. The study results show that changes in positive and shear stresses at the fault face caused by the security pillar retrieval process are the main factors influencing the fault slip. The upper side of the fault tends to slip along the fault face during the security pillar retrieval process, which theoretically prevents the transfer of subsidence displacement caused by underground mining to the roadside (foot side of the fault). The presence of the F317 fault has less effect on the tensile stresses at the road protection zone. Still, the fault allows the tensile stresses to be concentrated at the top and bottom of the quarry and at the isolated pillar, which is more likely to cause the rock to be stretched and squeezed. Without the F317 fault, the maximum subsidence displacement at the road protection zone is 30.59 mm, the maximum X-directional displacement is 42.17 mm (both of which are greater than the safe displacement limit by 20 mm), and the maximum Y-directional displacement is 19.75 mm, which is less than the safe displacement limit by 20 mm. Compared with the case without the F317 fault, the displacement at the road protection zone with the F317 fault is smaller, with a maximum subsidence displacement of 16.92 mm, a maximum X-directional displacement of 19.63 mm, and a maximum Y-directional displacement of 3.35 mm, all of which are less than the safe displacement limits. Therefore, the presence of the F317 fault provides some protection to the west side of the road from collapse due to underground mining.

Geotechnical analysis of blasting sequence and resulting shapes of drawbells in block cave mines

ABSTRACT Drawbells allow disassembled ore to be extracted from the production levels in block cave mines. As part of the construction process, blast damage must be minimised, enabling the remaining rock mass surrounding the drawbell to sustain the induced stress during the different stages of a block-caving operation for a successful mine plan extraction and ore recovery.This paper proposes two approaches for the geotechnical evaluation of drawbell blast performance. Initially, the expected dynamic burden is calculated along the length of the blasthole and used to assess surveyed blast holes. Secondly, the design compliance is evaluated using the Radial Distance of Over/Underbreak concept, which compares designed and scanned shapes relative to height and radial orientation.The results have identified confined blast zones at the top and around the corners of drawbells. Excessive confinement may cause damage to the pillars and negatively impact the stability of the production level.

Performance indicators and their importance for effective short-term and operational mine planning

Mining in Brazil is one of the pillars that support its GDP (gross domestic product). Its execution requires technique and expertise. In a mining venture, the value chain drives the business to achieve its goals. Mine planning has a great influence on its performance, as it is through it that the organization is based to offer its products to the market and, consequently, the low compliance with the established premises will bring undesirable inconveniences. Within the planning, the short term is dedicated to operationalize the plans made possible by the long and medium term teams, in addition to attending to market variations. The indicators that control this process are of great importance, as an incorrect identification inserted in the various criteria that compose it can guide managers towards inefficient decision making. The objective of this study was, through lean methodology, to identify the main performance indicators that impact on the non-exception of the mining plan measured by the adherence and compliance indicators. In this method, the main causes of non-adherence and compliance with the mining plan were identified, enabling short and medium-term actions that leveraged the indicators. This study leveraged the average adherence and compliance by 17% and 54.9%, respectively, exceeding the target set for 6.5% and 49.2% respectively.

Investment Project Analysis of PT. Berau Coal Block 5-6 Binungan Using Discounted Cash Flow Method

The evaluation of business projects that have high complexity and uncertainty will require a thorough study since the coal mining industry is a business that has extremely high costs as well as a high risk where there are many uncertainty elements that impact this sector. Blocks 5 and 6 are locations that have previously been mined by PT. Berau Coal in an effort to boost output. PT. Berau Coal now wants to reopen the block 5-6 region to optimize the area that was previously deemed unproductive for mining in an effort to boost coal output there. To assess if the block 5–6 region can be mined once more in an endeavor to increase PT. Berau Coal's production reserves, an analysis is thus required. PT. Berau Coal currently uses the Discounted Cash Flow (DCF) approach to determine the viability of an investment. The mathematical results of the DCF technique will be taken into account by management when making mining decisions. Further research is required to be able to maximize shareholder value because this technique has a restriction in that it does not offer flexible project for management. We obtain an NPV of $14,44 million, an IRR of 67,98%, and a Payback Period of 3.4 years based on the results of the DCF calculations performed on the Block 5-6 project from the mine plan for PT. Berau Coal. There are a number of preparations that must be made for the mining plan for this project, including the building of farm roads to replace existing roads that are part of the mining plan and pumping operations to lower the water level in the mining plan area. There is no new investment required because the infrastructure for mining equipment is already a part of the contractor selection component and the infrastructure for processing coal already uses it.

Integrating flexibility in open pit mine planning to survive commodity price decline

Historically the mining industry grew substantially across the globe, acquiring new licenses, investing in exploration activities, and opening new mines along with the boom in commodity prices. However, the steady decline in mineral commodities prices significantly affects mineral industry as well as commodity producing nations. Mining risk management is undertaken to mitigate the adverse effects of uncertainties such as price fluctuations using Net Present Value (NPV). In this article risk management of commodity price decline was undertaken by integrating a recourse action with mine planning. The framework was presented in four distinct phases namely commodity price simulation using autoregressive distributed lag forecasting method; formulation of the mathematical stochastic phase design structure of the stochastic graph framework, and parametric solution of the graph problem; estimation and analysis of risk by Value at Risk (Var) and Weibull exceedance of losses concepts respectively, and minimizing the risk by optimizing operating level using the Lagrange model on Cobb-Douglass model. The proposed methodology was applied on an anonymous gold mine and the analysis of potential losses using Gumbel exceedance shows that mine could incur an annual loss of $20 million with a recurrence period of 1 in 1.38 years with a probability of 0.72. The recourse action was identified using the Lagrange model on the Cobb-Douglass model which reduced the cost by about 50% and subsequently the production level. The NPVs for the stochastic minimum cut models after application of the recourse action was 54% of the NPV at full production showing that there is an increase in the value of the project.

Effect of Long-Term Stockpiling on Oxidation and Flotation Response of Low-Grade Copper Sulphide Ore

Since the start-up of the Sossego copper concentrator, located in the Carajás Mineral Province in the southeast of Para State, Brazil, the low-grade ore (~0.34% Cu) has been stockpiled, as defined in the long-term mine plan, to be reclaimed at the end of the mine life. Given this imminent need to process around 40 Mt of this low-grade ore, questions have been raised related to the extent of oxidation that might have occurred in this stockpiled ore. In this context, a study was designed to characterize the stockpiled ore and assess the effect of the ore oxidation on its flotation response. A sampling campaign of the stockpiled ore was carried out to analyze the main variables that could influence the level of oxidation, and, consequently, copper recovery, such as stockpiling time, depth, and particle size. The results showed that there are two main factors negatively impacting the copper recovery of the low-grade stockpiled ore: the surface oxidation and the level of liberation of the copper mineral. Depth and period of stockpiling were not found to influence the level of oxidation, nor the flotation response. An empirical model was proposed for the copper recovery in the rougher stage, which resulted in a predicted value of 90.7%, which was lower than that for the fresh (and higher copper content) ore fed to the plant (93%).

Ground Response of Non-Coal Pillar Mining Panel

The mining-induced ground response (MIGR) has a critical impact on safety management, the mining plan, and entry support. A clear understanding of the characteristics is the foundation of the MIGRs scientific control. This study is the result of the MIGRs development of the non-pillar mining panel with gob-side entry by roof cutting (GSERC). Comprehensive research of the in situ measurements, numerical simulation, and theoretical analysis to determine the ground response characteristics, including mining panel and GSERC, were implemented. The results indicate that the MIGR presents the characteristic of asymmetric development and that the ground response near the non-roof cutting side is more significant than that near the roof cutting side. The development stage of the entry convergence of GESRC can be divided into seven stages; the primary rapid development stage should be paid more attention to in the support process. The entry convergence rapidly increases to 275 mm, 380 mm, 410 mm, and 525 mm, respectively, for the roof cutting rib to the virgin coal rib, the roof near the virgin coal side, the roof of the middle section, and the roof near the cutting side. The hydraulic support end cycle resistance at the roof cutting side and the middle section of the mining panel with the value of more than 30.8 MPa is greater than that at the non-roof cutting side with the value of less than 26 MPa, which presents the asymmetric feature. The numerical simulation results regarding vertical stress development, vertical displacement, and horizontal displacement also presents the asymmetric feature. The MIGR division is divided into five divisions. Division II (the middle section of the panel) and division IV (the entry range near the roof cutting side) should be paid more attention to in the panel mining process. The results of this study can provide technical guidance and theoretical reference for similar engineering practices.

Investment Project Analysis Pit CACD Block 8 Using Discounted Cash Flow (DCF): A Case Study of Pt. Berau Coal

PT Berau Coal which is located in Berau Regency, East Kalimantan Province. Pit C2 Block 8 Binungan Mining Operation Area 2 PT Berau Coal is a coal mining operation area with multi-seam characteristics with a slope of coal seams at intervals of 40 – 60 degrees. The characteristics of coal deposits are one of the considerations in the formation of coal mining designs in collaboration with other disciplines, including geotechnical, hydrology, safety and environment, as well as other aspects. PT Berau Coal faces several challenges, risks and uncertainties such as fluctuations in coal prices, production capacity, mining costs and related legal aspects. Therefore, mining planning and strategy must be carried out carefully until PT Berau Coal's mining permit expires in 2025. Financial assessment must accommodate the risks and uncertainties that exist to overcome the weaknesses of the DCF method. The monte carlo symulation method serves as an alternative for creating dynamic quantitative models for mining projects. In this method, the discounted risk factor is applied directly to variables of uncertain sources, such as coal prices, to improve accuracy. Therefore, evaluating long-term mine planning at PT Berau Coal using scenario analysis and Monte Carlo simulation is useful for making better decisions in production, investment and resource allocation schemes. With the results of a financial evaluation of NPV DCF 38mio USD, NPV Monte Carlo 40mio USD, IRR 51%, PI 4.12, and PBP 2.28 years PT Berau Coal will consider and make a decision whether to continue the project considering several risks or cancel the investment and not continue mining in Pit CACD.

Bergbaukunde, quo vadis?

ZusammenfassungUm dem Klimawandel und dem zunehmenden Wettbewerb beim Zugang zu Ressourcen zu begegnen, hat die Europäische Union im sogenannten Green Deal weitreichende Transformationen in den Bereichen Energie und Digitalisierung sowie die Umstellung des Wirtschaftssystems hin zu einer inklusiven Kreislaufwirtschaft festgelegt. Aus Sicht des Bergbaus bedeuten diese Transformationen einen weiterhin wachsenden Rohstoffbedarf, der durch die Gewinnung mineralischer Rohstoffe aus primären Lagerstätten gedeckt werden muss. Gesteigerte Mengen mit „Business as usual“ würden allerdings auch die Umwelt- und Sozialauswirkungen des Bergbaus steigern, was vor allem in Europa und Österreich keine Option darstellt.Aufgrund dieser Tatsachen ergibt sich Forschungsbedarf für neue und verbesserte Abbauverfahren und -planung ebenso wie für optimierte Prozesse und Maschinen. Im vorliegenden Artikel wird beschrieben, wie der Lehrstuhl für Bergbaukunde, Bergtechnik und Bergwirtschaft an der Montanuniversität Leoben mit seiner aktuellen Strategie, sowohl für die Forschung als auch für die Lehre, diese Herausforderungen als Chance nutzen möchte. Für den Forschungsbereich soll dabei die Nachhaltigkeit und Involvierung in die Gestaltung von Rohstoffpolitik den Rahmen bilden. Mit einer Fokussierung auf die Digitalisierung und den untertägigen Bergbau sowie der Stärkung der Bereiche Tagebau, Fördertechnik und Geoinformatik soll die Forschung für die anstehenden Transformationen zukunftssicher ausgerichtet werden. Die Lehre wird inhaltlich weiterhin eine ingenieurwissenschaftliche Grundausbildung mit Spezialisierung auf den Bergbau beinhalten, wobei die Digitalisierung eine zunehmend stärkere Rolle spielen wird.

Geometallurgical Detailing of Plant Operation within Open-Pit Strategic Mine Planning

Mineral and metallurgical processing are crucial within the mineral value chain. These processes involve several stages wherein comminution is arguably the most important due to its high energy consumption, and its impact on subsequent extractive processes. Several geological properties of the orebody impact the efficiency of mineral processing and extractive metallurgy; scholars have therefore proposed to deal with the uncertain ore feed in terms of grades and rock types, incorporating operational modes that represent different plant configurations that provide coordinated system-wide responses. Even though these studies offer insights into how mine planning impacts the ore fed into the plant, the simultaneous optimization of mine plan and metallurgical plant design has been limited by the existing stochastic mine planning algorithms, which have only limited support for detailing operational modes. The present work offers to fill this gap for open-pit mines through a computationally efficient adaptation of a strategic mine planning algorithm. The adaptation incorporates a linear programming representation of the operational modes which forms a Dantzig-Wolfe decomposition, nested within a high-performing stochastic mine planning algorithm based on a variable neighborhood descent metaheuristic. Sample calculations are presented, loosely based on the Mount Isa deposit in Australia, in which a metallurgical plant upgrade is evaluated, showing that the upgraded design significantly decreases the requirement on the mining equipment, without significantly affecting the NPV.

Environmental Noise Impact Assessment for Large-Scale Surface Mining Operations in Serbia

Noise emissions are a significant environmental impact caused by the mining industry in all technological phases of surface mining, mineral processing, and waste disposal. This paper presents the role of noise impact assessment and control in large-scale surface mining operations. Mine planning develops the model of mining operations, ore excavation, and waste dumping scheduling and processing rates, including spatial distribution of mining activities. Such a level of mine planning requires an environmental impact assessment study. This can be achieved by applying noise impact assessment models. The described approach can be used to verify the effectiveness of the proposed protection measures to reduce or eliminate the identified negative impacts. This paper presents a case study of environmental noise impact assessment and control at the Serbia Zijin Copper DOO Bor mine, encompassing the analysis of the noise protection measures efficiency within the planning of large-scale mining operations at the open-pit mine Veliki Krivelj.

The Dump is the Target—A Reversed Mine Plan

Mine plans usually need to consider the tonnage that must be stored in the dumping area and the machine hours required to place material there as a constraint. The Department of Mining Engineering and Mineral Economics was involved in a project, in which the whole mine planning procedure had to start with the dump. To start with a dump, formulating the targets for the mine plan did require some adaptation of the standard mine planning procedure. After a proper set-up, the schedule was updated several times to optimize it. In total, six complete scenarios have been created where the dam could be built in the simulation.For confidentiality reasons no details on the project location or project coordinator are included in the text.

A novel geostatistical index of uncertainty for short-term mining plan

ABSTRACT The uncertainty associated with geostatistical estimates is as important in a model as the estimated value itself. This uncertainty is commonly assessed through different scenarios obtained by geostatistical simulation methods. Although the applications of geostatistical simulation methods have grown significantly in recent decades in long-term modeling, the same improvement has not occurred in medium- and short-term modeling. This study presents the “geological-operational risk indicator,” which comprises: (1) the uncertainty of geological contacts, determined by the variance of the sequential indicator simulation; and (2) the continuity of grades, obtained by sequential Gaussian simulation for variability of grades in relation to the economic or operational limit of that variable. The proposed index is applied to five grade variables of a short-term model of the Capitão do Mato iron mine in Brazil. The results are satisfactory and advance the concept of a geological risk indicator that is appropriate for medium- and short-term operations. This novel indicator helps to predict and manage in advance the uncertainties associated with mining plans.

Assessment of the capability of SWAT model to predict surface runoff in open cast coal mining areas.

The hydrological response of watersheds affected by large-scale coal mining activities is complex and difficult to simulate. The present study aims to bridge this gap by simulating the effects of land-use and topographical changes due to coal mining on surface runoff in the Jamunia basin of Jharkhand, India. The derivatives of digital elevation model (DEM) have been used to simulate the changes in topography of the study area and the runoff has been calculated using Soil and Water Assessment Tool (SWAT) hydrological model. The study results revealed significant increase in surface runoff (mm) during the simulation period. The findings of this study established that unplanned mining activities can reduce the water holding capacity of downstream reservoirs and increase the runoff. The outcome of the study will be helpful for mine planners to design sustainable mining operations which will have less adverse impact on the hydrological regime of the watershed.

ЗВ’ЯЗОК ГЕРМАНІЮ ІЗ ЗОЛЬНІСТЮ ТА «ТОКСИЧНИМИ» ЕЛЕМЕНТАМИ У ВУГІЛЛІ НА ПРИКЛАДІ ПЛАСТА с5 ПОЛЯ ШАХТИ БЛАГОДАТНА ЗАХІДНОГО ДОНБАСУ

Purpose. The character and level of the statistical relationship between the content of germanium and “toxic elements” in coal seam c5 of the “Blahodatna” mine and the main features of their distribution were established for the assessment of possible environmental risks during the selective processing of coal enriched with this element. It has been proven that the correlation between germanium and all “toxic” elements is inverse and very weak. The existence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium was revealed. Methods. The research materials included analysis of 38 coal samples for germanium, beryllium, fluorine, mercury and arsenic, performed in accredited state laboratories after 1981. The content of germanium, beryllium and fluorine was determined by quantitative emission spectral analysis, mercury and arsenic – by atomic absorption analysis. The samples were taken during the work of production enterprises and research organizations with the participation of the authors, using the furrow method of sampling in mine workings and from the core of wells from 1981 to 2018. For primary processing of geochemical data, STATISTICA 13.3 and IBM SPSS Statistics 22 were used to calculate basic statistical characteristics, including mean, standard error of the mean, median, kurtosis, mode, standard deviation, variance, minimum and maximum values, coefficient of variation, and sample skewness . Frequency histograms were created for visual assessment of the studied parameters, as well as the characteristics of their distribution were determined. To achieve the objectives of the study, correlation and regression analyzes were carried out using the functions available in Micromine – the leading professional mining and geological information system for 3D modeling, statistical data processing and mining planning. Results. It was established that a general feature of the distribution of ash content, germanium, arsenic, fluorine, mercury and beryllium in the c5 coal seam of the Blahodatna mine field is their non-compliance with normal and lognormal laws and the polymodality of the distributions with a shift of the density nuclei to the left, except for beryllium and germanium. Each of the studied elements in seam c5 of the “Blahodatna” mine accumulated in several forms, which differed significantly in their genesis. At the same time, the forms of finding, which are responsible for the minimum contents, were jointly accumulated at the initial, syngenetic stage. The presence of an inverse and very weak correlation between germanium concentrations and ash content, arsenic, fluorine, and mercury contents in the c5 coal seam of the Blahodatna mine was revealed. The only element considered that forms a very weak positive correlation with germanium is beryllium. Scientific novelty of the results. The presence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the Blahodatna mine was revealed. The polymodality of the distributions was established for all the considered components, while the displacement of the density of their distribution to the left was proved, except for germanium and beryllium. It has been proven that the correlation between germanium and ash content and all “toxic” elements (except beryllium) is inverse and very weak. Practical significance of the results. Justification of the method of the most accurate assessment of the central tendency in the distribution of a sample population of concentrations of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the “Blahodatna” mine. The presence of a very weak correlation between the content of germanium and “toxic” elements makes it possible to predict the minimal nature of possible environmental risks during the selective processing of germanium-enriched coal.

FORECASTING OF THE PARAMETERS OF MICRO-FAULT OF COAL SEAMS USING ARTIFICIAL INTELLIGENCE

Purpose. Research and development of a method for predicting micro-fault fractures in coal seams using artificial intelligence methods. Methodology. To carry out the study, a neural network of the sing structure was formed. The training of the network was based on the principles of natural selection, which is the strongest one. The implementation of this principle was designed to support the genetic algorithm. Each network was tested for fitness, proportional to its ability to predict, and the best one was used for forecasting. The forecast was made in such a way that from the base point the forecast was made for the entire project site. Results. The research was conducted to develop a method for predicting the coordinates and amplitudes of low-amplitude disturbances using neural networks and genetic algorithms.The method consists in training a neural network based on reliable data taken from mining plans and, after a certain number of trainings, forecasting micro-fault discontinuous disturbances on the project site. The parameters of the violations revealed by tunnelling and cleaning works are used as training data. Originality. The method of forecasting micro-fault discontinuous disturbances using artificial intelligence allows predicting the presence and probability of distribution of disturbances in the predicted area. The main advantage of this method is the minimal cost with sufficient reliability. This favourably distinguishes it from the known methods. The application of this method does not require the use of special equipment in mine conditions, which significantly reduces the labour-intensiveness of the forecast. The efficiency of this method allows you to quickly and in a short time make a forecast on a given site, which contributes to the fastest possible commissioning of new mining fields. Practical value. The proposed method can be used to predict micro-fault discontinuous disturbances in the extraction fields of mines in the Ukrainian Donbas to assess the reliability of working out the extraction pillars and ensure the stability of the preparatory works due to their rational location. At the same time, the forecasting technique is being improved, taking into account the main characteristics of the physical process of the genesis of micro-fault discontinuous disturbances.

Управление качеством углей по критерию их опасности с использованием цифровых моделей полезного ископаемого на Кутинском буроугольном месторождении

The purpose of the research is to substantiate the need for preliminary planning with the use of block models in the extraction of TPI as an important element of designing an economically and environmentally efficient enterprise for the development of a deposit of solid minerals. The object of the study is the Kuta brown coal deposit, which has areas of coal with increased concentrations of natural radionuclides. The method of planning the quality of coals, taking into account the hazard criterion and products of their processing with the use of Micromine Alastri software (software) is considered. The objectives of the study are to test the author’s hypothesis regarding the use of BM in the process of predicting the quality of the extracted PI according to the obtained characteristics. Expected results of the scientific study: it is expected that the specific activity in the samples of dust and slag will be recorded several times; when conducting field studies on the content of carbon in coal seams and coal dust with the inclusion of rock, it is necessary to establish the regularity of increasing the value of Aeff in coal dust with the inclusion of rock particles relative to coal samples. The results of the interpolation of the contents of the ORE into the blocks of the digital block model of the coal seam I of the Kuta brown coal deposit are presented. In conclusion, the author highlights the methodology for determining the parameters of mined coal and coal products, taking into account the hazard criterion, which has the following logic: burning of an experimental batch of coal; analysis of the correlation regularity between the average content of OER in coal by block and the average content of OER in coal combustion products, determination of the dependence of the oxygen content in coals and combustion products; assignment by reverse interpolation of the obtained forecast values to each three-dimensional block of the block model included in the mining blocks for each horizon and their transfer to the maps of horizon-by-horizon mining planning. Thus, obtaining a safety map of the extracted PI with the predicted values of the content of N in the combustion products.

Future of Mining and Geology: Increase in the Use of Cave Mining Methods to Extract Ore Over the Next 30 Years

Abstract The mining industry faces a period of increasingly difficult challenges over the next 30 years. The increasing demand for traditional mineral resources will likely continue unabated as developing countries modernize and the transition from fossil fuels to renewable energy sources ramps up. Compounding the challenge will be more rigorous constraints on mining imposed by environmental, social, and corporate governance (ESG) standards and regulations, as well as the progression from open-pit and shallow underground deposits to large, deeper, potentially lower-grade deposits, where underground mass mining methods are the only viable option. The latter change will especially apply to metals that are critical to mass electrification, including the traditionally required metals such as Cu, Ni, Co, Mn, Zn, U, etc. The more expensive-to-produce critical metals, such as Li, rare earths, high-purity alumina, etc., are currently only used in smaller quantities, and thus open-pit mining of these may remain viable until their near-surface resources are depleted. The large-scale mining of Cu, Ni, and Mo in particular will increasingly rely on cave mining methods, as these are the only profitable underground methods capable of yielding the large tonnages necessary to meet global demands, such as raising living standards within developing countries and providing the foundation for mass electrification of modern society, and all at a time when shallow deposits mined by open pit are becoming scarce. The application of cave mining is thus expected to increase in the future for deep mineral deposits with characteristics that are suited to this mining method. However, poor cave mine performance and/or unpredicted rock-mass responses (e.g., mine-induced seismicity) during cave mining can threaten the viability of the mine and will reduce investor confidence in this method. Irrespective of whether mining is of a traditional metal on a very large (mass) scale, or of a presently critical metal that now has lower tonnage requirements, we predict that geology will need to be more comprehensively considered during mine planning and design—right from the early stages of mine study—because of the uncertainties that the host rocks (geology) present to mining. This will be especially important in complying with the ESG constraints that are being applied to mining companies, in addition to the concept of sustainability that they also seek to address. We review—and propose remediation research of—the various geology-related issues that are already causing concern during mass underground mining by caving of Cu ore; some of these issues are equally applicable to other types of mining, such as open-pit and narrow-width extraction.