Статьи журнала - Горные науки и технологии
Все статьи: 1030
Статья научная
Geostatistics-based estimators, i.e. ordinary kriging and simple kriging, are state-of-the-art estimation techniques widely used in the mining industry. However, the estimation result of kriging techniques is not able to cope with the well-known uncertainty of geological attributes in mineralization deposits. Moreover, the smoothing effect of kriging algorithms has led to over/under estimation in many circumstances. To overcome these drawbacks, the deterministic estimation result of kriging is usually followed by stochastic results provided by stochastic simulation. In this paper, the application of ordinary kriging and stochastic simulation are performed to build the resource model together with the uncertainty assessment of the Sinquyen copper mine.
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Статья научная
This article presents a study on the application of remote sensing techniques to detect clay minerals, iron oxide and ferrous minerals using LANDSAT 7 ETM+ multispectral images. We used band ratio method to determine areas that are rich and poor in mineral composite content. The results obtained in this study can be used to create a distribution map of clay mineral and iron oxide, and to facilitate mineral mining and exploration
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Approach of recovering thin coal seams
Статья научная
The Mae Moh basin is situated in the Mae Moh District of Lampang Province, which is about 26 km east of Lampang City. The basin floor is about 320340 m above mean sea level. The Mae Moh basin consists of three formations, namely the Huai King, Na Khaem, and Huai Luang formations, in ascending order. The total thickness is nearly 1 000 m in ascending order. The Na Khaem formation is a coal measure comprising three main coal zones, Q, K, and J. This study introduces preliminary approaches to determine minimum thickness to excavate thin coal seams within coal quality requirements or maximum dilution thickness acceptance. The approach considers heating value as a main parameter to determine under different scenarios of loss and dilution. The results indicate the high quality of coal-bearing soil seams, such as BK and BK3 can be excavated with K3 and acceptable dilution thickness is between 1.685.3 m at 2 800 kcal/kg of heating value. These dilution thickness can be converted to 2050 % at any excavated thickness of K3 coal seam. Low quality of coal-bearing soil seams, such as TK1, TQ and BQ4, cannot be excavated with any K and Q coal seams. Coal-bearing parting layer should have heating value more than 1,000 kcal/kg to possibly be excavated with coal seams.
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Behaviour of pollutants in the upper reaches of East Jiu river case study
Статья научная
Surface water pollution is one of the consequences of modern society development through permanent pressures on the environment imposed by economic activities to provide the necessary resources for keeping modern living standards. Degradation of fresh water bodies is caused by the disappearance of natural water collection areas, deforestation and unsustainable farming practices, river pollution with wastes and the discharge of non-treated domestic and industrial wastewater into natural recipients. The main purpose of the mathematical modeling of rivers is to predict pollution dispersal in longitudinal and transversal directions, taking into account water body mixing coefficient. This paper is devoted to monitoring of physico-chemical indicators in the sampled river reaches and simulation of pollutant dispersal in the upper reaches of the East Jiu river.
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Статья научная
Oltenia’s coal basin occupies an area of 4500 km2 and has the most important deposits of lignite in Romania, many of which are exploited through open-pit mining works. Open-pit lignite exploitation involves occupancy of large areas of land on long-term and considerable negative changes of physical, chemical and structural characteristics that define the regional elements, resulting in full damage of the existing landscape. Recovery and rehabilitation planning of a remaining void represents an essential step and consists into establish and implement the necessary measures of reasonable accommodation of land so that it is compatible with the environment, and aims at reintegrating degraded land in the landscape and increases its value. Choosing the final use of a remaining void is made taking into account criterias such as the climate, land morphology, slope stability conditions, regional development strategy, community requirements, financial resources, etc.
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Статья научная
An analysis of the constraints that apply the technology and the complexities of the mining and geological conditions of the Quang Ninh coal basin. The possibility and expediency of using the foreign experience of working out of the medium thick inclined coal seams in the mines of Vietnam. The scheme of preparation and working out of the excavation area is given in view of the technological features in difficult mining and geological conditions, using the room and pillar system and determination of the rational length of the block along the strike.
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Development of automatic system for Unmanned Aerial Vehicle (UAV) motion control for mine conditions
Статья научная
Underground mining operations are connected with significant risks of technogenic accidents, which can be catastrophic. Mitigating the consequences of such phenomena directly depends on the reliability and efficiency of information about the state of parameters of many technological processes, mine workings and facilities located in them. At failure of standard systems of industrial telemetry in conditions of underground mining the creation of new information channels and places of information measurement becomes practically impossible in case of emergency situation development. This predetermines necessity of use of essentially new systems of gathering and transfer of the information, based on robotized autonomous complexes. The task of acquiring reliable information about the situation in an emergency mine working with the help of drones (unmanned aerial vehicles or UAV) in order to make rational decisions in the course of the rescue operation is quite relevant. The aim of the paper was to develop a system of automatic control of an unmanned aerial vehicle (UAV) movement in confined space of a mine working, with significant perturbations of the mine air flow. The mathematical model of UAV movement in mine conditions, based on Euler angles or quaternions, was substantiated. The method of positioning through triangulation with the use of radio beacons was accepted as the basic method that allowed to determine the current position of an UAV. It was proposed to solve the problem of creation of the automatic system for an unmanned aerial vehicle movement control with the use of a hierarchical multiloop control system. The route planning algorithm was formed on the basis of the Dijkstra algorithm. For this purpose, discretization of the future motion space was performed, a labeled connected graph was constructed, on which the arc weights were the distances between the route points. A simulation experiment was implemented. The average deviation from the planned trajectory when flying at a speed of 10 m/s with payload mass up to 0.6 kg did not exceed 1 m, and the maximum deviation was unacceptably large. When flying at 6 m/s with payload mass up to 0.6 kg the average deviation did not exceed 0.3 m, and the maximum deviation, 1.2 m. The results of simulation of movement along the route towards the disturbing mine airflow showed that the control system allowed the UAV with payload of 0.6 kg to withstand the oncoming flow up to 8 m/s. It was obtained that with payload mass of 0.6 kg, the braking distance does not exceed 6 m if the UAV had a speed of 6 m/s, and the braking distance does not exceed 12 m at the speed of 10 m/s. The performed simulation studies confirmed the operating capability of the developed system for automatic motion control.
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Driver safety system implementation in Europe
Статья научная
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.
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Статья научная
The horizontal wells have been adapted to use for dewatering purpose in the mining industry. Due to unique characteristics, those horizontal filters are recommended to utilize not only the mechanical strength but also the hydraulic performance. Pressure drop along the horizontal well is a major factor that affects the performance of a wellbore. The pressure drop incurs due to four separate effects: wall friction, perforation roughness, inflow acceleration and mixing effects. This work presents the effects of the two first factors in perforated or slotted pipes, which correspond to the case of no flow through the wall. Numerical analysis was carried out with different types of perforations and slots. The simulated model accomplished using ANSYS Fluent 14.5. The results revealed that at high Reynolds number, the roughness friction factors in circular perforated pipes are significantly greater than those in axial slotted pipes and perpendicular slotted pipes.
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Статья научная
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 scientific/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...
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Статья научная
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, thenand 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.
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Identification of the sources generating impact on the water quality of the East Jiu basin
Статья научная
The main economic activity in the Jiu Valley is mining, which provides to the society an important content of mineral raw materials required for the development and progress, representing the main activity in producing the value chain. The majority of the mining activities and other economic activities deployed along the basin of the East Jiu generates both negative environmental impacts (more or less serious) and positive impacts such as those related to employment, staff training, creating infrastructures etc. In the most cases, the negative impacts of the human activities can be much improved up to a point or even eliminated through the remedial measures, particularly through environmental rehabilitation of the affected areas. But if a watercourse is strongly affected by sediments generated by the human activity still on the top side, the pollution will be intensifed much more on the bottom side with signifiant changes on the aquatic ecosystems and with an impossibility of consumption and the use of the water resources by the riparian population...
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Improvement of technology and jar mills for preparation of coal-water fuel from waste coal
Статья научная
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.
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Статья научная
Khanh Hoa coal mine (Thai Nguyen province) is one of the largest coal mines in the north of Vietnam. For many years, this area suffered from underground fires at coal mine waste dumps, seriously affecting production activities and the environment. This paper presents the results of classification of underground fire areas at Khanh Hoa coal mine using Normalized Diference Coal Fire Index (NDCFI). 03 Landsat 8 OLI_TIRS images taken on December 2, 2013, December 10, 2016, and December 3, 2019 were used to calculate NDCFI index, and then classify the underground fire areas by thresholding method. In the study, the land surface temperature was also calculated from Landsat 8 thermal infrared bands data, and then compared with the results of underground coal fire classification at Khanh Hoa coal mine. The obtained results showed that the NDCFI index can be used effectively in detecting and monitoring underground fire areas at coal mines. The use of the NDCFI index also has many advantages due to its calculation simplicity and rapidness compared to other methods for classifying underground coal fire areas.
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PEST-анализ развития Нивенского ГОКа на территории Калининградской области
Статья научная
Сегодня, в реалиях экономической неопределенности и непредсказуемости, важно своевременно реагировать на новые вызовы, используя актуальные инструменты для принятия эффективных управленческих решений. В мировой практике одним из таких инструментов для эффективного управления проектами промышленных предприятий является PEST-анализ, функциональные возможности которого рассмотрены в данной работе. Цель исследования заключается в проведении PEST-анализа, рассмотрении и анализе факторов, оказывающих влияние на развитие Нивенского ГОКа, расположенного на территории Калининградской области, – экспортно-ориентированного инвестиционного проекта строительства нового промышленного предприятия с основным производством премиального минерального удобрения – сульфата калия. Посредством проведенного анализа полученных результатов в статье предложен ряд возможных превентивных мероприятий для нивелирования негативных факторов, а также для развития сильных сторон компании-оператора Нивенского ГОКа – ООО «К-Поташ Сервис». Таким образом, PEST-анализ ключевых микро- и макроэкономических факторов позволил комплексно оценить положение Нивенского ГОКа в создаваемой горно-химической промышленности Калининградской области. В работе установлена степень влияния на компанию и других внутренних и внешних факторов, включая возможности внедрения новых инновационных технологий в работу промышленного предприятия, тенденции развития рынка минеральных удобрений с учетом геополитического контекста. Выводы, рекомендации и предложения позволяют оценить компанию со стороны, а полученные результаты учитывать возможности развития промышленного предприятия при принятии стратегических и долгосрочных решений по развитию проекта. Основные результаты проведенного исследования могут быть использованы в качестве эффективных мер развития проекта нового промышленного предприятия – Нивенского ГОКа.
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Статья научная
The paper is devoted to studying the possibility of using artificial neural networks (ANN) to estimate ground subsidence caused by underground mining. The experiments showed that the most suitable network structure is a network with three layers of perceptrons and four neurons in the hidden layer with the back propagation algorithm (BP) as a training algorithm. The subsidence observation data in the Mong Duong underground coal mine and other parameters, including: (1) the distance from the centre of the stope to the ground monitoring points; (2) the volume of mined-out space; (3) the positions of the ground points in the direction of the main cross-section of the trough; and (4) the time (presented by cycle number), were used as the input data for the ANN. The findings showed that the selected model was suitable for predicting subsidence along the main profile within the subsidence trough. The prediction accuracy depended on the number of cycles used for the network training as well as the time interval between the predicted cycle and the last cycle in the training dataset. When the number of monitoring cycles used for the network training was greater than eight, the largest values of RMS and MAE were less than 10 % compared to the actual maximum subsidence value for each cycle. If the network training was less than eight cycles, the results of prediction did not meet the accuracy requirements.
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Research design lining for utilities tunnel in the city based on state of "lining-massif soil"
Статья научная
Nowaday, in order to resolve the problem of utilities tunnel in large cities is very necessary. The technical pipelines, power cables, plumbing, drainage,... in the large cities such as Hanoi, Ho Chi Minh is still a problem with no explanation. Within the paper, the method to calculate the anti-tunnel structure of small tunnel by small tunneling machine. In fact, due to the condition of the soil is not good and the limited construction conditions, it is necessary to calculate the composition of the tunnel for the tunnel. For each area to ensure stability, aesthetics, economics,... for the project.
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Rock burst and actually effective bolting for rock burst prevention
Статья научная
Rock burst represents a very dangerous phenomenon in deep underground mining, as well as for underground structures in unfavourable conditions (great depth, high horizontal stress, proximity of major tectonic structures, etc.). The rock burst problem relates to the natural and mining conditions of the rock mass. The evaluation of rock burst is becoming increasingly important as mining activities reach greater depths. In the literature, rock burst assessment challenge was tackled by many researchers using various methods. However, no study providing review and comparison of different rock burst assessment methods is available. In this paper, rock burst classification is briefly summarized. This includes a classification based on rock burst type, and another classification based on rock burst severity. As an important method for rock burst prevention, some novel energy-absorbing bolts were developed. These bolts demonstrate constant resistance under both static and shock loads and large elongation ability enabling them to withstand large deformations of rock masses under rock burst-prone conditions. Among the novel energy absorbing bolts, Modified Cone Bolt (MCB) and Constant Resistance at Large Deformation (CRLD) Bolt are selected to be presented in this paper.
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Selective extraction of cobalt and copper from Chilean mine water by ion exchange resin
Статья научная
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).
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Status of development orientations for mining titanium placers in Vietnam
Статья научная
Vietnam has potential reserves of titanium placers, located mainly along the coast of the Middle spreading across provinces from Thanh Hoa to Ba Ria - Vung Tau. Mining titanium placers deposits has gained considerable profit for localities and the country as a whole, but it has also given rise to significant environmental issues. The paper introduces the potential of titanium placers in Vietnam, current mining status and environmental issues faced, and then proposes a number of strategic orientations for sustainable development of the future titanium industry of Vietnam. These orientations are completely feasible with regard to the titanium placer mines of Vietnam in order to consider and apply effectively for suitable conditions. They also represent a useful reference for similar titanium placer mines in the world.
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