It is traditionally believed that the use of high-performance mining equipment in collieries leads not only to increasing productivity of the enterprise, but also to significant increasing release of methane into the mine air. Based on this, the existing regulatory and methodological support for calculations allowed predicting the rate of methane release into the mine air and determining the required operating modes of the ventilation system to ensure mining safety. The task of this study is to investigate in practice the laws of methane release as a function of the productivity of mining equipment and to identify phenomena that affect the nature of these laws. Based on the data of air gas monitoring, the results of statistical study of methane release in 101 working faces of 33 collieries of Kuzbass are presented. In 76 working faces, parabolic law of the dependence of the methane release on the productivity of mining equipment, having peak points in relation to the rate of advance and productivity of the shearer were established with high confidence. Using the law of A. Darcy and the equation of sorption of I. Langmuir, it has been theoretically established that methane release from loose coal is a function inversely proportional to the linear hyperbolic dependence, and also has a peak point in relation to the rate of advance and productivity of the shearer. Analysis of the established dependence of the rate of methane release from the loose coal shows that the methane release significantly (quadratically) decreases with decreasing the rotational speed of the cutting auger and the number of cutters in the cutting line or the number of blades on the drum. Methane release also quadratically increases with increasing formation thickness and the shearer cutting width. The extreme dependence of the rate of methane release from loose coal forms two areas of allowable rate of advance and productivity of the shearer by gas factor.
Reservoir simulation is a powerful tool to mimic the formation behaviour during primary production and later on for planning enhanced oil recovery (EOR) pattern. However, all available commercial and developed scien-tific/academic software for this purpose is based on either finite difference method (FDM) or finite volume method (FVM). Recently finite element method started to gain more attention in the scientific and commercial practices due to its robust results and the ability to deal with complex boundaries. COMSOL Multiphysics is a finite element method (FEM)-based software, having very special features, which are different from standard reservoir engineering software packages like Eclipse or CMG, which are black box-type software. The most important feature of the COMSOL is that user can see equation and modify it - customize for specific conditions and objectives, as well as couple different physics together and apply different solvers, which are under user’s disposal. In this paper, short background of FEM will be illustrated and then the mathematical models of two-phase immiscible flow of water and heavy oil will be reviewed and simulated using COMSOL Multiphysics on the famous inverted five-spot model. The comparison between the results of Comsol Multiphysics and Eclipse shows good agreement. This study is the first step in applying Comsol Multiphysics to reservoir simulation. Further steps will involve simulating thermal enhanced oil recovery using steam flooding technique and coupling Comsol Multiphysics with CMG software package to enhance simulation inputs and outputs.
The process and equipment have been developed for preparation and burning (at small and medium capacity boiler plants) of slurry coal-water fuel, produced from finely dispersed coal preparation waste (filter cakes) from coal preparation plants of Komsomolets Mine and Named after S. M. Kirov Mine. It was shown that, based on these wastes, it is possible to produce slurry coal-water fuel with solids content of 56-60 %, the required structural and rheological characteristics, and lower heating value of up to 13 MJ/kg. Based on the research findings, detail design was developed for creation of the pilot process complex for processing of waste coal to produce slurry coal-water fuel for burning at boiler plant. Assessment of using the whole volume of the SUEK Kuzbass coal preparation plants waste coal at the nearby Belovskaya SDPP was performed, which showed high economic and environmental efficiency of the proposed project.
In mining technical literature, the prevailing idea is still that rockbursts in open pits and underground mines are caused by gravitational forces produced by the overburden rock mass, put forward in the 20th century by S.G. Avershin and I.M. Petukhov. This concept is the basis for the rules of safe mining at rockburst-hazardous deposits, including modern guidance documents of Rostekhnadzor. Numerous studies of the behavior of a rock mass as a geological medium, the phenomena causing rockbursts in underground workings, the mechanisms of manifestation of rockbursts and rock-tectonic bursts change many ideas. They have now become urgently needed to explain the causes of particularly powerful geodynamic phenomena in mines - rock-tectonic bursts, technogenic earthquakes - phenomena that were practically not observed in the 20th century. Intense geodynamic events in mines (rock-tectonic bursts, technogenic earthquakes), comparable in energy level to natural earthquakes, have once again shown their analogy with natural earthquakes to be studied by seismology. M.A. Sadovsky et al. established the law of self-similarity of seismic process at different scale levels. Based on this law, the relationships established for seismic focuses proved to be applicable to dynamic manifestations of rock pressure at mines. In this paper, further details of this analogy are developed. It shows which forms of dynamic manifestations of rock pressure correspond to which sizes of structural heterogeneity of rock mass. Based on the law of self-similarity of seismic processes at different scale levels, we showed that the energy characteristics of the rock pressure manifestations at mines obey the laws established in seismology.
The paper presents comprehensive studies of abutment pressure formation zones in the geotechnical system of "paired drifts", including numerical simulation based on the finite element method. For the simulation, the Mohr - Coulomb elastic-plastic model was used, as well as physico-mechanical properties of coal and host rocks. The simulation was carried out for specific mining and geological conditions of k2 anthracite seam occurrence. In a software module, several stages were simulated, allowing to determine magnitude of stresses and displacements of the roof in stopes at various stages of abutment pressure formation in front of the advancing stoping face. As a result of the simulation, the values of the stresses and displacements of the roof in the rock mass around the stopes at various stages of the development of the abutment pressure formation zones were obtained, enabling using the experimental design method to optimize the parameters of adjustable pillar (as support structure). These studies are aimed at improving efficiency of stope protection by optimizing the parameters of protective support structures (adjustable pillars) to increase productivity of the stoping face during excavation of flat-lying anthracite seams, including rockburst-dangerous ones.
The features of originating load on “support-interframe shield” system in the process of formation of broken rock zone around a mine working were investigated by laboratory tests on models of equivalent materials and structural models. The role of interframe shield in the formation of frame support load has been revealed. It was found that a natural self-supporting arch is formed over interframe shields within the broken rock zone, which redistributes the load on the roof support frames, while the weight of rocks within the arch puts pressure on the interframe shields. The requirements for interframe shield of frame supports in mine workings have been developed.
Development of economic sectors related to mining and processing industries is largely determined by national approaches to subsoil use regulation. For the Republic of Kazakhstan, having enormous geological potential, it is relevant and significant to develop and use globally competitive approaches to public administration of subsoil. Achieving these goals allows building in foreseeable future the potential for consistent and secure participation of the national economy in market interaction with leading global partners on mutually beneficial terms. In the paper, emphasis is placed on the fact that, despite forecasted promising geological data, significant excess of the scope of mining work over that of exploration is observed in the Republic of Kazakhstan. This is accompanied by low investment potential of the exploration sector. To solve the accumulated problems in the field of subsoil use, an analysis of the current situation was carried out, the causes of the current circumstances were identified, and the suggestions were made for improving the system of and approaches to public administration of subsoil, with justification of their effectiveness. The analysis convincingly showed that the reforms carried out in the field of subsoil use in the Republic of Kazakhstan and the changing trends in the global economy strongly require revising the previously used approaches to public administration of subsoil for developing the most effective system of public administration of subsoil. The study examined the international experience of public administration of subsoil in the countries that have achieved the greatest progress in this field, identified the basic principles in building a system of public administration of subsoil use, conducted historical analysis to determine the effect of the methods and approaches selected by state for subsoil administration at different stages of economic development. Based on the study findings, the risk zones of inefficient public administration of subsoil were identified, and approaches to improving the system and methods of public administration of subsoil in the Republic of Kazakhstan were proposed.
Globalization of the energy feedstock market has led to the fact that, in recent decades, parameters of the thermal coal market significantly changed. Depletion of “rich” deposits implies development of new deposits of more complicated structure and characteristics. The paper proposes a new approach to managing quality of marketable products in the course of development of a coal deposit of complicated structure, which has demonstrated its effectiveness in the conditions of the Beisky deposit. The approach to managing quality of the marketable products is based on the concept of the relevance of improving the quality of technological processes and their differentiation according to the criterion of the maximum ratio of value and cost of the products. Typical solutions are proposed, and the results of implementation of the developed methodological approach to managing quality of the marketable products as exemplified by the Vostochno-Beisky open-pit coal mine are presented. Methods of analysis of technological factors governing the selection of parameters of the process operations were used, and the substantiation of the processes for preparation of blocks, excavation, transportation, storage and processing of products in conditions of open pit mining of a coal deposit having complicated structure was performed. The implementation of the developed technological solutions in the conditions of the Vostochno-Beisky open-pit coal mine allowed to obtain positive results, expressed in the growth of quality indicators of the marketable products by 4-6 %
One of the most problematic aspects in underground ore extraction in mining-disturbed rock masses is backfilling of man-made voids, which affect origination and redistribution of stress-strain state of the rock mass. Their existence in the earth's crust provokes subsidence/collapse of the day surface and also contributes to arising geomechanical and seismic phenomena. The purpose of the study is to substantiate environmental-friendly and resource-saving methods for backfilling of voids in underground ore mining based on revealing the features of rock integrity of the day surface and life-sustaining activity of the population living in the mining-affected area. The main negative consequences of the impact of mining on the environment and humans are high costs for conserving day surface and ensuring life-sustaining activity of the population living in the mining-affected area, as well as removing large areas of land from human activity, etc. Based on the study of a rock mass stress-strain state using geophysical and surveying methods, an environment-friendly method for backfilling of man-made voids in disturbed rock masses is proposed. It enables ensuring the integrity of the day surface and life-sustaining activity of the population living in the mining-affected area (in the vicinity of mines, dumps, sites of backfilling complexes, preconcentration and heap leaching of metals from substandard ores, tailings storage facilities, etc.). Combined geotechnologies are proposed for backfilling of voids during the development of ore deposits by underground block leaching, and scientific and methodological and technical support was provided for drilling and blasting preparation of hard ores and underground leaching of pilot blocks at the Michurinsky deposit of GP VostGOK, Ukraine. The research findings can be used in underground mining of ore deposits of complicated structure.
The tasks of continuous optimizing production, looking for ways of increasing performance, cutting mining costs and expanding mineral resource base of a mining enterprise are becoming more relevant than ever in conditions of the current negative trends at the world market of uranium resources. Increasing enterprise competitiveness requires permanent improvement of approaches and methods for managing performance of production blocks of a mine and ensuring the necessary volumes of reserves prepared for production. In the study, a theoretical information analysis of the process flow sheet of commercial ISL uranium production was carried out. The regression relationships between the main indicators of the production process cycles were determined, and the task of controlling production blocks at the stages of acidification, active leaching, completing operation, and decommissioning was formalized. The statistical characteristics of a production block cells and the distribution of uranium reserves, obtained based on the data of ore body drilling-in, as well as the analysis of the dynamic pattern of uranium production and recovery by production block depending on time, the balance of production block productivity by pregnant and leaching solutions enabled calculating key geotechnological indicators that formed the basis for calculating regression relationships between the uranium recovery and the ratio of the leaching solution amount to the rock mass amount, as well as for estimating specific consumption of sulfuric acid and electricity depending on operation time. This approach allowed identifying the problem areas and promising ways for improving the control procedure and performance of ISL mine wellfield operation. The planned measures will allow re-estimating resource potential of a production block while simultaneously providing a reasonable forecast of the residual uranium reserves in the being exploited and drilled-in blocks, reducing costs at the main development stage, and, by providing timely decommissioning of the blocks, reducing power consumption, optimizing sulfuric acid consumption, and overall improving quality of projecting and planning the production indicators for achieving uranium production targets. The study results can be used for improving short- and medium-term planning of technical and economic indicators of main development and production based on the forecast of ore interval sizes in production blocks that contributes to strengthening resource base and increasing capitalization of a company.
The Earth remote sensing technologies (ERS) in exploration largely determine their effectiveness. Therefore, development of a new methodological support for the use of remote sensing data in predicting mining and geological conditions is a key priority area. The studies are based on the analysis of the assessment of information, social, and economic efficiency of remote sensing data application at mineral deposits. The role of application of new technologies (including remote ones) in the process of optimizing initial exploration stages is noted. The possibilities of using remote sensing data to assess general nature, direction, and extent of environmental changes due to mining activities are shown. A technique is proposed that can be used in the process of tracking changes in the topology of objects in the course of mining. The differences in the results obtained using the proposed technique for processing satellite images on rectangular and hexagonal grids (rasters) are considered. The advantages of using the hexagonal grid for tracking the boundaries of objects and formation of signs are shown. Practical examples - a number of open source satellite images processed using the proposed method - are presented. The study findings allow applying intelligent analysis of satellite imagery data with the subsequent identification of the earth's surface objects of interest. An example of using the obtained results together with specialized software tools (such as GIS INTEGRO geographic information system capable of solving geological problems, or the foreign ArcGIS system) for constructing contour maps of the territory and obtaining its description based on topological relations and metric information is shown.
The Republic of Azerbaijan has significant potential in the oil and gas industry, which is the basic for the country economy. Prospects for the development of oil and gas production technologies are largely determined by the effectiveness of geological and geophysical surveys and exploratory drilling. The features of the geology and oil and gas potential of the Azerbaijanian continental depression zones are considered for determining the targets for further exploration for hydrocarbons (HC). The analysis of such studies shows that the Srednekurinskaya depression (the Azerbaijani part) and the Guba-Divichinsky depression are superimposed with the corresponding features of the conditions for the formation and survival of hydrocarbon accumulations. Low oil and gas potential of the Miocene-anthropogenic strata of the discussed superimposed depressions is substantiated: this is due to low hydrocarbon potential of the rocks (especially the Lower Pliocene ones), as well as low temperatures insufficient for the conversion of organic matter to hydrocarbons. It is proposed to use poorly tectonized Jurassic and Cretaceous sediments, especially those overlaid by oil and gas generating Paleogene-Miocene strata (commercial accumulations of Muradkhanli type) as the HC exploration prospects.
Gravity methods are widely used for processing of gold ores. But many aspects of these processing techniques require improvement. In the study, methods of fire assay, gravimetric, chemical, mineralogical analyses of gold ores were used. In terms of sulfide sulfur content and degree of sulfur oxidation, the gold ore is assigned to the low-sulfide type of ore in the primary zone. Mineralogical analysis showed the ore-bearing rock is represented by phyllite. Gold in the ore occurs mainly in the form of free large and fine particles. The fine gold is closely associated with pyrite. GRG test was carried out for assessing gravity dressability of the gold ore. The total gold recovery is more than 41 %. The highest gold recoveries were achieved at the first stage at 100 % of -1.6 mm ore grain size, and at the third stage at 80 % of -0.071 mm ore grain size. This indicates that both relatively large gold and fine free gold particles are present in the ore. This is also confirmed by mineralogical analysis. The GRG test results showed that the gold ore can be effectively concentrated using centrifugal concentrators. The level of gold recovery by gravity at the multi-stage ore grinding is quite high. When developing the ore concentration process flow sheet, gravity separation in centrifugal concentrators should be included.
The paper considers a specific case related to the development of a program for upgrading soft skills of employees of maintenance service in mining and processing industry, and its testing in actual practice of the production cycle rearrangement. The project aim is to assess the potential of introducing the principles of advanced training from the viewpoint of psychological readiness of employees for changes at an industrial enterprise. The degree of effectiveness of this staff training method is considered. The project objectives are aimed at forming groups of workers based on the degree of their influence on the changes produced; the incoming assessment of readiness to fulfill the role of “change champions” is studied; implementation of training activities aimed at improving employee's readiness; output assessment of the training activities effectiveness is produced. In the project implementation, the following methods and tools were used: soft skills-based approach, sociological and expert surveys, statistical analysis, trainings and chalk and talk sessions, solution of theoretical and practical cases (problems). Based on the results of the implemented soft skills changing (upgrading) program, the dynamics of increasing psychological readiness of employees (who participated in the proposed training activities) to accept large-scale and local changes was revealed. The study findings present rationale for investing funds of production companies in proactive and advanced development of employees from the standpoints of both professional competencies and soft skills aimed at psychological readiness for changes and understanding the need for lifelong learning of engineers and technicians, being effective "change champion" in production activities.
Until now, the intensification of ion exchange processes (sorption, desorption, washing of ion exchanger) remains an urgent problem in obtaining commercial strippants. This paper presents the study of ultrasonic (US) effects on the process of uranium sorption from pregnant solutions by ion-exchange resin at operating in-situ leach recovery (“ISR”) uranium production. The study and evaluation of effectiveness of ultrasonic intensifying the ion exchange processes was implemented at one of the mines of NAC Kazatomprom JSC. Ultrasonic pulses periodically generated by emitters produced effects on the whole working space of the mass transfer apparatus. Thus, the whole mass of reagents is kept in continuous motion, and the whole surface of the anion exchanger grains is permanently purified during the ultrasonic device operation. The study findings showed that the ultrasonic intensification of the sorption process allows: - increasing the sorption rate by 6.4 times at uranium concentration in the pregnant solutions of 0.003 g/m3; - increasing the sorption rate by 1.4 times at uranium concentration in the pregnant solutions of 0.014 g/m3; - achieving weighted average increasing the sorption rate by 1.3 times through applying the ultrasonic treatment; - increasing full dynamic exchange capacity of the ion exchange resin for uranium in 1.13 times at keeping mechanical strength of the ion exchanger grains.
Heavy metal-containing waste has become one of heavy environmental problems. Processing of such waste accumulated at waste dumps to extract valuable components is commercially beneficial activity and, in addition, decreases environmental impact. In this study, Lewatit MonoPlus TP 207 (TP 207) ion exchange resin was evaluated for its suitability for selective removal of cobalt (Co) and copper (Cu) from mine waste waters, generated by heap leaching waste materials at a Chilean copper mine. In series of laboratory scale fixed-bed ion exchange column tests, the effects of process parameters, such as waste water flow rate and regenerant (sulfuric acid) concentration, were studied in both waste water treatment by the ion exchange resin process and the resin regeneration (metals eluting) process. The regeneration process tests were performed using 1 % and 10 % sulfuric acid. The best separation of the metals (in the eluting process) was achieved with regeneration of TP 207 resin using 1 % sulfuric acid at flow rate of 1 bed volume per hour (BV/h).
Extraction of coal measures leads to origination of a large number of increased rock pressure zones in rock mass, caused by the influence of abutment pressure of rock mass edge parts and pillars kept in adjacent seams. The presence of such zones sharply worsens the condition of development and permanent workings when developing coal measures. The paper presents the findings of the observations made in the areas of the underground workings in coal mines of Karaganda coal basin, located under and above pillars and edge parts of overlying coal seams. If abutment pressure under pillars and edge parts of coal seams has been studied quite actively, abutment pressure above the pillars and the edge parts of the coal seams has not been practically studied. The findings of the performed studies showed that in all the workings in which the observations were made, the height of the workings located underneath the pillar (the edge part) varies wavily. The studies revealed wavily behavior of the stationary abutment pressure propagating along the seam, in which the working is located, according to the law of damped sinusoid while increasing distance from the source of the abutment pressure. At the same time, the half-wave length λ/2 corresponds to the thickness of the main roof above the working. The height of the workings located above the pillar (edge part) also varies wavily. At the same time, the nature of the abutment pressure influence varies depending on the distance of the working from the pressure source and is determined by undermining factor Ku. The abutment pressure half-wave length corresponds to the step of secondary collapse of the main roof of the coal seam on which the pillar (edge part) is located.
The launch of the Russian-Germany interstate project (the Russian-German Year of Scientific and Educational Cooperation 2018-2020) sets new requirements for the agenda formation for interstate cooperation in the field of education and science. The “Russian-German Roadmap for Cooperation in Education, Science, Research and Innovation” (the Roadmap) defines new opportunities for expanding cooperation between states in the educational and research fields, as well as developing economical innovations. The key directions of the cooperation are: “Large research infrastructure”, “Priorities”, “Young talents”, “Innovations, science and society”. The expansion of bilateral cooperation on a wide range of topics, the development of large research infrastructures and joint research projects in particular, will be carried out in the areas that are priority for both countries. By means of the Roadmap, young scientists should be supported, and the academic mobility of researchers, students and postgraduate students should be increased. It is also planned to enhance the transfer of research results to the real economy, as well as increase the advanced innovative business involvement in the partnership. One of the tasks that the organizers of the year face, is to create conditions for the public presentation of specialized events, as well as the dissemination of cooperation practices in the academic environment. For this purpose, a special website to gather the information from participants and organizers of events implemented in both countries, was launched (https://russia-germanycooperation.ru). The inclusion of innovative business in the year’s action field will create conditions for the formation of joint teams, both in the academic and professional environment, aimed at tackling new problems of states economies' innovative development.
This paper presents the experiences obtained in the application of Principal Component Analysis (PCA) method to map hydrothermal minerals based on remotely sensed data. In this study, Sentinel-2B MultiSpectral Instrument (MSI) image is used to detect distribution of hydroxyl-bearing minerals in Vinh Phuc province, northern Vietnam. Four bands of Sentinel-2B image including blue band (band 2), Vegetation Red Edge band (band 8A) and SWIR bands (band 11 and 12) are used to calculate the Principal Components, then and then select the Principal Component, which containing provides information on the hydrothermal minerals information. The obtained results findings show that the methodology and data are effective in detecting and mapping hydrothermal mineralization.
In mining industry safety is top priority. There is a request for safety management, risk prevention and operator training. Operator fatigue and distraction leads to dangerous situations. The paper is aimed at reviewing the issues of fatigued or distracted driver operation. This is achieved through creating models in occupational safety strategies. Hereafter the implementation of fatigue and distraction control system within a pilot project is discussed. The pilot project was aimed at collecting realistic operation data from mining industry in Europe. Caterpillar Inc. offers a solution called Driver Safety System (DSS). When driver’s micro-sleep is detected, the system alerts operator through different alarms directly. Dangerous events are also recorded and classified individually in 24/7 monitoring centre. The DSS was tested at European limestone open pit mine with typical working regime. This paper discusses theories, results and transferable insights of the study.
