rss_2.0Mining Revue FeedSciendo RSS Feed for Mining Revue Revue 's Cover Influence of Physical Parameters on the Mechanical Characteristics of Some Volcanic Magmatic Rocks of the Andesite Type<abstract> <title style='display:none'>Abstract</title> <p>The factors that influence the strength characteristics of rocks can be different in nature, being divided into external and internal factors. The mechanical properties of hard rocks are a result of geological, physical and chemical factors. In order to highlight the physical parameters that influence the strength characteristics of the rocks, in this paper there were analyzed six types of volcanic magmatic rocks such as andesites. In terms of stress behavior, rocks are directly influenced by their physical properties, such as volumetric density, porosity, compactness, moisture and the degree of alteration of mineral components. For this purpose, several sets of tests were performed to determine the physical and mechanical characteristics of the rocks, based on which it was possible to analyze how the physical parameters influence the strength characteristics.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Update of the Ventilation Network Related to Livezeni Mine<abstract> <title style='display:none'>Abstract</title> <p>The ventilation networks are associated with the set of underground mining works used for the extraction of useful mineral substances. Over time, the ventilation networks involve a change in the structure due to either the expansion or restriction of the mining works structure. For the establishment of air flows at the level of each active mining work, specialized programs are used at international level. These programs allow the modelling and solving of complex ventilation networks. The most advanced specialized programs are those from the VENTSIM range. The paper presents the updating of the ventilation network related to Livezeni mine, with the help of the VENTSIM program.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Analysis of Methods for Preventing and Fighting the Self-Heating Phenomena of Coal Used in Jiu Valley Mines<abstract> <title style='display:none'>Abstract</title> <p>This paper deals with the analysis of two cases of coal self-heating from two longwall mining within the coal exploitations belonging to Complexul Energetic Hunedoara, phenomena that started similarly but later evolved differently, as a result of prevention methods applied or not applied in each case. For the analysis of these self-heating phenomena, the data collected after the occurrence of the first signs were used, respectively the emission of carbon monoxide in the longwall mining area, until the moment of desertion and closure of the longwall with dams in the first case and eradication of the phenomenon in the second case. By analyzing in parallel the two cases, several conclusions are drawn which may help to counteract these types of phenomena that may occur in the longwall exploited in similar conditions.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Using the PIV Techniques in the Expertise of Gas Explosions<abstract> <title style='display:none'>Abstract</title> <p>Given the possibilities offered by PIV systems, it was considered appropriate to test them in the study of the formation of explosive atmospheres. In this sense, within the INCD INSEMEX Petroșani laboratories, a test stand was created subject to the conditions of applying PIV techniques. Thus, this stand was built of transparent materials, having the possibility to introduce, in the inner volume, the suspended particles and the combustible gas, being at the same time able to be sectioned by the light plane generated by a laser source and to provide the recording conditions using a CMOS camera. The physical experiments concerned both the situation of a normal atmosphere inside the test stand and the situations of the appearance of a fuel gas leak and an efficient source of initiation of the formed explosive atmosphere.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Monitoring and Forecasting of Surface Deformation at Victoria and Cantacuzino Mines<abstract> <title style='display:none'>Abstract</title> <p>The underground mining of the rock salt deposit from Slănic started in 1665, with the Old Mines and continued in 1970, with Victoria Mine, then in 1993, with Cantacuzino Mine. The mining method applied at Victoria and Cantacuzino mines was the one with small rooms and square pillars, with which over 9.7 million m3 of rock salt were extracted. This very large volume of underground mining voids led to the convergence of the underground excavations and thus to the deformation of the surface. This article presents the analysis of the measurements of surface displacement and the prediction of its subsidence over time. Also, the main factors that contributed to the deformation of the surface are analyzed, namely: the dimensions of the underground voids, the mining depth, the geomechanical characteristics, the tectonics and microtectonics of the deposit, the hydrogeology and the effect of blasting.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Modeling of the Complex Ventilation Network Related to Livezeni Mine<abstract> <title style='display:none'>Abstract</title> <p>In order to ensure the microclimate conditions for the exploitation of useful mineral substances underground, it is necessary to ensure the control of gas emissions from the field and from the exploited space. For this it is necessary to ensure a balanced air flow at the level of each active mining work in order to dilute the gases. Specialized programs are used to ensure the optimal distribution of air flows at the level of each mining work. The paper presents the modelling and solving of the ventilation network related to Livezeni Mine with the help of the 3D CANVENT program.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Spatial Representation of Useful Minerals Deposits<abstract> <title style='display:none'>Abstract</title> <p>Starting from the fact that in the mining industry and in general in the field of underground constructions, the topographic activity, regardless of which of its manifestations, conditions and substantiates the achievement of economic and technological objectives, implicitly resulting in the dependence between topographic precision and qualitative and quantitative performance of mining. The level at which the professional responsibility of the topographic activity, as a whole is engaged in the achievement of some proposed objectives, depends on the framework resulting from the technological complexity of the mining activity in the conditions of its restructuring and efficiency. Spatial representations of useful mineral deposits in the earth's crust, which meet the quality conditions necessary for the design of underground mining works, can be used to choose the most efficient methods of opening, preparation and exploitation of useful mineral deposits. These analyzes are the basis for the realization of underground topographic networks that have a precise connection with the topographic base at the surface. The use of stereographic projection and stereographic networks can be achieved by faithfully representing the tectonics and positioning of deposits of useful mineral matter inside the earth's crust.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00The Impact of Exploiting Lignite in Lupoaia Open Pit on Environmental Water<abstract> <title style='display:none'>Abstract</title> <p>The impact of extracting lignite in Lupoaia open pit over waters is local and regional, and temporary. The hydrographic network in Lupoaia open pit depends on River Motru, with its afluents, Ploștina and Lupoița Valley Rivers. The aquifers are to be found in the coal layers V-XII, mainly of sands formation. The impact over water in Lupoaia consists of water pollution and of changes in both the quality and the quantity of ground and surface waters. The surface waters are polluted resulting in industrial wastewaters, household wastewaters and waste rainwater. The wastewater is polluted within maximum admitted limits. The quality of groundwaters is influenced and modified by extracting coal resulting in the extinction of some aquifers. Environmental risks that can occur when extracting lignite are water floods, landslides, disasters which can be prevented by building guard channels around the open pit. The actions for reducing the impact are, in general, accomplished through monitoring both the water pollutants and the morphological changes caused by extracting lignite. That is why wastewater treatment plants must function. The impact of the activity in Lupoaia open pit over the hydrographic net of the area is to be observed during the entire extracting period, and monitoring this activity is highly demanded by the European environmental protection laws.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00The Share Distribution and Precision Evaluation in Underground Topographic Routes and Networks<abstract> <title style='display:none'>Abstract</title> <p>The underground topographic works of elevating and drawing are necessary for the execution of underground works (mining, hydrotechnics, communications, etc.) Fulfilling these works efficiently and safely requires an advance study for the precisions in topographic support routes and networks. This paper aims to establish the share distribution correlated with the underground works distribution.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Environmental Impact Assessment Related by Energy Sector in Rovinari Mining Area<abstract> <title style='display:none'>Abstract</title> <p>In this article an impact assessment is carried out, generated by activities in the energy sector related to Rovinari mining area. Energy-related activities in this area are carried out by open pit mining activities in the context of Tismana, Roșia, Pinoasa, Peşteana and Rovinari locations and Rovinari thermal power plant. Some information that has formed the input for the author’s approach has been provided by SC. Complexul Energetic Oltenia SA (CEO) and S.C. Institute of Scientific Research, Technological Engineering and Mine Designs on Lignite S.A. Craiova (ICSITPML) which has been processed, analysed and used for the presented environmental impact assessment. Two methods from specialized studies have been used for the impact assessment, namely: the Matrix Method for Rapid Impact Assessment (MERI) and the Method for Integrated Quantitative Impact and Risk Assessment of Environmental Pollution (EIRM). Based on the analysis carried out, it can be concluded that the activity in this sector does not lead to significant negative effects strictly associated with it.</p> </abstract>ARTICLE2021-07-15T00:00:00.000+00:00Solubilization Processing of Ashes Power Plant<abstract><title style='display:none'>Abstract</title><p>The paper presents the attempts of acid and alkaline solubilization of the power plant ashes, using different chemical reagents, at different concentrations. Due to the mineralogical content of these ashes, was elaborated a technological flow for the recovery the iron minerals, resulting an ferrous concentrate containing noble metals. For their recovery from ferrous concentrate, were studied properties of gold, silver and platinum, the conclusion being that these chemical elements can be extracted, in economic conditions, with sodium hypochlorite.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Correlation of the Local Projection System with the National System<abstract><title style='display:none'>Abstract</title><p>In areas with border extension (localities, mining areas, hydrotechnics, etc.) it is advisable to establish the positions of the points in a local system, the methods used being simpler and the results more precise. However, it is necessary to transcalculate the coordinates from the local system to the national projection system. A transcalculation method is assumed to ensure efficiency and accuracy.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00An Innovative Method for Testing Electronic Detonating Caps Regarding Sensitivity to Electrostatic Discharges<abstract><title style='display:none'>Abstract</title><p>The paper present the issue of explosion risk assessment presented by the risk of accidental initiation of electrical detonating caps and pyrotechnic articles. The purpose of the explosion risk assessment is to establish appropriate protection measures to prevent or limit them.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Impact of an Abandoned Mining Site - Central Flotation Platform<abstract><title style='display:none'>Abstract</title><p>The paper highlights a strong environmental impact due to a mining perimeter (Central Flotation - Baia Mare) in which significant quantities of complex and concentrated ores were abandoned without the most basic protection measures against environmental factors. The period of time since the cessation of activity has been more than 14 years, during which time an extreme reactivity took place, generating an acid drainage with very low pH and heavy metals exceeding hundreds and even thousands of times the maximum allowed values. These waters reach the natural receptors directly or infiltrate the groundwater. Another serious aspect is given by the fact that this site is located in the middle of the busiest community in Maramureș County (upstream of Baia Mare) and close to rural communities that practice agriculture and animal husbandry. Alongside the already existing environmental problems in the perimeter there is also added seepage of mine water through the exit of the tunnel from the Herja mine. Also adjacent is the Central pond with a supply of mine water and toxic dust.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Risk of Exposure for Workers to Professional Vibrations<abstract><title style='display:none'>Abstract</title><p>The study focused on the model of estimating the risk of exposure of workers to global occupational vibrations / with local action on the hand-arm system. In order to estimate the risk of exposure to occupational vibrations, we developed a generalized mathematical model for estimating the risk of exposure to mechanical vibrations transmitted to the whole body / with action on the hand-arm system. This model is based on the statistical function of probability with exponential decrease (Gumbel function), and its argument is expressed either by the values of the weighted acceleration parameter or in the form of exposure points.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Assessing the Suffosion Risk for the Final in-Situ Slopes of the North Peşteana Open-Pit<abstract><title style='display:none'>Abstract</title><p>With the occasion of complex and detailed studies, conducted especially from the geotechnical point of view (between 2016 and 2019), on the North Pesteana mining perimeter (more precisely on the lignite open-pit with the same name) numerous areas affected by suffosion were highlighted, mainly located on the lower steps (steps III and IV). Starting from these observations, the present paper analysis the risk of suffosion phenomenon to occur in the case of the final slopes of North Pesteana open-pit. In general, as observed, these areas have small and medium sizes, and do not affect significantly the stability of the steps, being immediately remedied with the advancement of the work front. Also, it was observed that, with the advancement of the excavation fronts, the groundwater currents constantly entrain the fine particles from the aquifer formations, and therefore new such suffosion areas occur. Taking into account the fact that the exploitation of lignite in this perimeter is ending soon, it was considered as necessary to assess the risk of suffosion at the final slopes (long term slopes) in order to be able to identify appropriate measures to prevent future potential catastrophic events.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Finite Element Modelling of the Stability of Underground Mining Excavations at Old Mines – Slănic Salt Mine<abstract><title style='display:none'>Abstract</title><p>The underground mining of the rock salt deposit from Slănic started over 350 years ago, in bell-shape room (Ocna din Deal and Ocna din Vale) and in large trapezoidal rooms (Carol, Mihai and Unirea mines), until 1970, generating a volume of underground excavations of over 5.3 million m<sup>3</sup>. Over time, these large excavations have lost their stability (collapse of the mines to the surface and various degrees of instability of the Carol and Mihai mines), keeping only the Unirea mine in operation for tourist purposes. This article is a synthesis of the analysis with 3D finite elements, in elasto-plasticity, of the state of stress and strain developed around the excavations and highlighting the factors that led to the loss of their stability, focusing on the Unirea mine.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Study of Reducing the Damage and Reuse of Waste Tanks in the Certej Mining Area<abstract><title style='display:none'>Abstract</title><p>The Certej area is an area of gold mining activities with a history of several hundred years. The only activity with a significant share in the area was the mining activity, which provided the population of Certeju de Sus commune and its surroundings with the means necessary for a decent living. In the case of tailings dumps, the soil suffers a combined impact - by removing large areas of land from the natural circuit and by generating acidic water. The geology and morphology of the region, characterized by the existence of surfaces with different slopes, are natural causes that attribute different levels of vulnerability to land at the onset of degradation processes by erosion, landslides and excess moisture. All these bring limitations in the use of land on the main uses: agricultural, forestry, construction, etc. The paper aims to provide solutions for the reuse of these lands, their use by recultivation, the search for plant species adaptable to soil conditions. A relatively small number of species were determined on the tailings dumps in the studied area, the spontaneous vegetation is visibly stressed by the existing conditions. As such, the method of ecological reconstruction of freshly deposited tailings dumps by the method of forest recultivation is proposed.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Increasing the Accuracy of the Orientation of Underground Topographic Works<abstract><title style='display:none'>Abstract</title><p>Geodetic and topographic works determine the necessary information base and of major importance in the design and management of underground construction works (mining, hydrotechnics, roads, etc.). The efficiency and safety of these investments with special financial implications depend on their quality. In this context, the geodetic orientation of the underground topographic works was the main and permanent subject of study and analysis on which this scientific paper refers.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00Mining Risks at Exploitation in Roşia Poieni Open Pit Mine, Romania<abstract><title style='display:none'>Abstract</title><p>The mining sector is a particularly important field that has the ability to support the economic development of a country by supplying various mineral products that are used as raw materials in other sectors of activity. When the depth at which a deposit is located and the geological conditions allow, the exploitation of useful mineral substances is realized through open-pit mine. The aim of this paper is to analyze the malfunctions that could occur and cause susceptible incidents and that could have consequences on staff safety and the environment. These malfunctions can have different causes: either an internal origin of the mining unit, or in natural phenomena. In this paper are identified and analyzed the potential mining risks that may occur in the Roşia Poieni open pit mine. The guidelines underlying the identification of these risks took into account three main principles: reducing risks for people, ensuring their security and at the same time limiting the risks on the property, respectively the financial risk for the mining unit. Acknowledge these risks, allows the delimitation of areas that are directly or indirectly exposed to potential risks and the establishment of specific measures for prevention, protection and security regarding the realized activities. Depending on the potential mining risks identified, we have made a hazard map that can be used to develop a risk prevention plan, taking into account the presence of several types of risks that may overlap in the same work area of the quarry.</p></abstract>ARTICLE2021-04-13T00:00:00.000+00:00en-us-1