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The paper presents model-in-the loop simulation results of the roadheader cutting speed control system. The roadheader is equipped with an 132kW induction motor supplied from the frequency inverter. The output frequency is calculated by a PI speed controller on the basis of speed error (signal difference between a reference signal from the load controller and the measured signal from the incremental speed encoder). The whole control system model (involving an inverter model, sensor model, induction motor linearize...

Belt conveying belongs to high-performance, economically and energy efficient continuous system. Optimization of this conveying systems makes possible reducing the total operating costs up to 30%. For this reason is necessary to choice of the suitable structural elements. Conveyor belt is the most important element of this system and quality of its strength properties is a needful prerequisite for a smooth operation of belt conveyors. Insufficient quality of strength properties has a negative effect on the reliabi...

It is a certainty that a rock massif is a very complex environment, known only partially; in the laboratory we cannot produce all the details encountered in situ; therefore, most of the properties determined experimentally not fully express their real value that they have in rock massif. As theoretical basis we might consider theory of similitude initiated by Newton, in the sense of similarity that we can establish to the boundary between theory and experiment. Based on this and considering the applicable theorems...

In a practical context and with a tendency to generalize the dependence between monoaxial and triaxial compressive strength of rocks and qualitative characteristics and also properties of connection between the elements that form the skeleton of studied rocks were analyzed. This qualitative connection was highlighted by means of void index and apparent specific weight. The obtained correlation can be generalized to any type of rock, if it takes into account the amount of adsorbed and absorbed water, the direction ...

The main aim of this study is separation of different populations for sulfur and phosphorus as harmful materials using fractal modeling in the Jalal-Abad iron ore, SE Iran. The elements are dangerous for steel production and environment and classification of those elements is important for excavation of iron ores. For this purpose, the grade distribution models for sulfur and phosphorus were generated using ordinary kriging geostatistical model. Then, the various sulfur and phosphorus populations were delineated b...

The belt conveyance plays an important role in mining, bulk material transportation, raw materials processing, and in many other areas (e.g., metallurgy, wood-cutting, and energetics) where large quantities are transported over the distances ranging from a few meters to several kilometres. A conveyor belt, as the basic element of the mining transport, is of particular economic significance. Increasing the belt service life, which can be achieved by reducing the wear of conveyor belts, has a high priority. The top ...

This article aims at developing a method to establish a model employment arrangement based on mining companies using a taxonomic approach and a similarity measure as well as potential practical applications of the presented studies. In order to establish the model employment arrangement, the author uses the production parameters of mining companies significantly affecting the number of employees. As a result, the following algorithm has been proposed: arranging mines into typologically homogeneous groups using the...

The progress (evolution) of a civilization based on natural resources development has resulted in permanent natural environment destruction. By the beginning of the third millennium it has become evident that exploitation of the planet's mineral resources, being the basis for the existence and progress of civilization, is the cause of the global environmental crisis. The Mining Institute has substantiated a methodology of restoration of natural ecosystems (ecological restoration), which consists in using an idea o...

The paper deals with the purchase and sale of electricity in companies like huge opencast brown coal mine. Regulation of electric energy usage is still an underrated component of automatization equipment in some companies. If good energy regulation methods are being used, not only financial saving will be achieved, but also energy supply and distribution system quality will get better. This article describes one of the most important systems for saving money and effectively managing the use of electricity in the m...

This article aims at determining the optimal number of organizational levels in a company's hierarchical structure. Based on this, the author establishes a certain number of managerial levels that simultaneously create the levels in the structure of the priority communication system ? information exchange ? in an organization. Also, the role of managers in an efficient and effective information flow is presented. Businesses that operate by market principles must strive for the highest possible efficiency and effec...

The publication concerns the issue of losses and gains related to the rock mining activity in the whole business life cycle of a mining undertaking in relation to: mining entrepreneur, communes, local communities and the environment. The analysis of the issues was conducted for three specific stages of a mining undertaking: identification of geological resources and technical and economic analyses of an undertaking, preparatory works, deposit opening and mining as well as winding up of the mine. The conducted anal...

The paper is aimed at estimating the abundance of polymetallic nodules in the Pacific area is administered by the Interoceanmetal Joint Organization (IOM) using statistical and geostatistical methods. Polymetallic nodules occurring in the Clarion-Clipperton zone in the Eastern Pacific Ocean contain numerous metals, of which the most important are Co, Cu, Ni, and Mn. In the area administered by the IOM, the four genotypes of nodules are marked with the following symbols: D and D1 (diagenetic), H (hydrogenic), and H...

Calculation of the mining support in tunnels and/or underground facilities can be based on application of contemporary numerical methods, but sometimes it can be performed with the classical methods too. These methods can be found to be used in order to choose variants and ways of supporting, but also in the moments that unpredictably appears during the construction of facility. Before installing a permanent mining support, these methods can help the projector at the selection of type of support and ways of tempor...

The methane hazard is one of the main natural hazards occurring in underground hard coal mining. This hazard is related to the potential ignition and/or explosion of methane when mixed with air. The underlying cause of this problem is methane release from the body of coal, the goaves with caving and the excavated coal area. The region most vulnerable to this hazard in coal exploitation during longwall ventilation using the U-type system from the exploitation field borders is the intersection of the longwall and th...

The accelerated ageing affects the quality of an important element of the belt conveyance ? a conveyor belt. This paper analyses the resistance of the belt cover layers to the deterioration caused particularly by the accelerated ageing. The investigation was carried out using the fabric conveyor belts of the P 2000/4 type (4-layer textile belts with a polyamide carcass, the strength of 2,000 N/mm) at different ageing periods. The effect of ageing on the rubber cover layers was identified on the basis of the observ...

The investigated lead - zinc ore panel is located in the Blaznei Valley ore deposit, Romania. Applying traditional methods for determining the average thickness proves useful in its exploration, although there are only four points of thickness measurement, located in each corner of the exploration panel. Later, in the second stage of the exploitation process (preparation), when the exploration panel becomes an operating (exploitation) panel by contour mining of four workings, two groves on direction and two runs, ...

The target of this article is the providing of the brief information about preventing the dust spreading problems solving during operations of machinery equipment in brown coal open pit mines and in coal dumps. The main part of this paper briefly describes operation tests of the new rotary mist unit realized during last years. The increased concentration of the dust in the air causes important health hazard. The dust is very bother factor. The occurrence of the dust in operation area is the source of danger fire r...

Various methods are used in the mining of minerals, where the transport of material is an integral part. This paper deals with the transport problem of backfill material from surface stock to underground tank. To solve the problem is applied the capacitive calculation of transport using 2 trucks and a loader. The calculation is complemented by graphic models. The backfill material is available on 5 surface stocks. It is possible to transport the material directly to the workplace from each heap, which is not effec...

The article presents the second part of the results of asymmetrical disc tools laboratory tests. The first part of this study was presented at SGEM International Conference in 2017. Asymmetrical disc mining tools can be used for mechanical mining of hard rocks, as an alternative to blasting methods. The study was conducted on a dedicated laboratory stand, with an installed drive power of 80 kW. Stand consists of rotating rock sample, mined by special plate equipped with asymmetrical disc tools by a so-called under...

Natural sources can contribute with significant radiation quantities toward the total radiation exposure that humans receive. The majority of this natural radiation is harmless to humans in the ambient environment. However, radon, a large component of the natural radiation which humans are exposed to, can pose a threat to the workers health when radon gas accumulates in poorly ventilated occupational settings. Radon is the most hazardous natural source of radiation. Even if it is an inert gas, having no color, tas...

The paper deals with the negative effects of mining on the transport network in the Moravian-Silesian area, especially is focused on problems reflected in construction layers of transport-related structures (railways, roads, area storage and handling areas). With the extraction downturn, the sources and objectives of transport have changed including the characteristics of transport flows of all traffic roads and connections. Various measures for all transport modes situated in Moravian-Silesian region are identifi...

The target of this article is the presentation of the first steps of solving the project No. TH03020368 from the programme EPSILON titled ?The optimisation of the shape and material of ground and mining machines research?. The main topic of this article is the optimization of the tooth shape and primarily the optimization of the materials used for manufacturing of cutting bodies of the ground and mining machines. This research is necessary for increasing of efficiency of mining process in conditions of the Most Ba...

In the combustion processes the nature and concentration of the developed gaseous effluents depends on the type of materials that are subject to combustion as well as on the conditions in which the oxidation processes take place. The purpose of this paper is the experimental determination of the combustion parameters and the study of the developed gaseous effluents from several combustible materials. The production of gaseous products resulting from combustion results in different yields depending on several param...

Production and consumption of electricity is, in contemporary society, the significant technical indices and social level you have reached. The use of electricity involves electric power systems (ESS), representing the large technical systems, which shall incorporate the Assembly plants for the production, transportation, distribution and consumption of electricity. Within the framework of the ESS are retrieved hydroelectric power plants (CHE), which represents about 25 percent of the installed power in power stat...

For underground extraction of coal are running a complex network mining vertical, horizontal and inclined role extraction, transportation and evacuation on the surface. Associated system of mining works has the ventilation network to ensure the oxygen necessary for workers, diluting explosive gases and toxic substances and evacuated heat and humidity from the underground. For air evacuation from the underground workings, from the point of entry of fresh air to the polluted air exit point, is used powerful fans loc...

Computer assisted design and simulation are essential stages in the process of creating a new technical product. The paper presents the utilization of cutting parts, equipping 2K-52 machines, as fundamental element in the development of modified cutting parts for KSW-460NE machine. This modification has been possible due to the study of the machine?s cutting parts with the help of CAD/CAE software. Adapting the cutting parts to KSW-460NE machine has been imposed by the geological-mining conditions of the coal laye...

The paper presents the results of the analysis of the accuracy of estimates of copper resources in parts of a Cu-Ag deposit in the Lubin-Glogow Copper District (LGCD) (Poland) where samples were not collected (test areas). The estimation was based on the samples collected from excavations surrounding the areas scheduled for mining activities, while the evaluation of the accuracy of the estimates was based on data obtained during the exploitation. The estimates of resources in the examined area were based on a 3D s...

In order to ensure energy security, at national level, coal constitutes an important source, though its share in the energy mix is reduced in the past few years in favor of clean technologies and on the background of the fall in the energy consumption. Where can be located in the project of energy security, the production of coal, exploited in the mining units in the Jiu Valley and valorized at the two power plants, Mintia and Paroseni-components of the Hunedoara Energy Complex, amid the request for intervention f...

Biomass belongs among renewable energy sources and its representation in national energy strategies is increasing due to the limited supplies of fossil fuels. One of the options for substitution of fossil fuels is short rotation cropping systems for woody biomass as a method of reclamation and revitalization of anthropogenic soil profiles during restoration activities in the areas after brown coal mining. The scope of the project "Methodology of sustainable agricultural management in anthropogenic damaged landscap...

The Cu-Ag deposit exploited in the Lubin-G?og?w Copper district (LGCD) in Poland is located in the Permian Rotliegend (sandstones) and Zechstein (shale and carbonate rocks) formations. The three main lithological series are not internally homogenous; within them, a total of 16 individual lithological units can be determined. The differentiation between lithological, mineralogical and geometallurgical ore properties is a criterion used to distinguish between main and individual lithologies in the deposit area. A sy...

The subject of the study was to characterize three deposit parameters of Pacific polymetallic nodules (the content and the abundance of nickel and the nodule abundance) using classical statistical methods. The input data points come from 448 sampling points of a bed area of about 48,000 km2 in the Clarion-Clipperton fracture zone (approx. 1,000 km west of the coast of Mexico). The sample points formed a pseudoregular grid with an average distance between them of about 10 km. On the basis of these, the basic statis...

A tough requirement for the development of the Partomchorr apatite-nepheline ore deposit containing rare-earth elements is a performance of environmental safety of production, because a sanitary zone of the projected mining and processing plant sides with the boundaries of the existing Simbozersky nature reserve and the created Khibiny national park. The studies have substantiated reasonability of the Partomchorr deposit development by a combined mining method; in the first stage step-by-step mining of four open p...

The basis for safety management is the assumption that safe conditions as well as safe behaviour at work do not arise spontaneously, but must be worked out according to a pre-approved program. It is known that preventive actions have a much greater importance and sense than the removing of a damage resulting from accidents. Therefore, it is necessary to take measures aimed at improving the working conditions, equipment and conduct of employees hired in the mine. The presented article is an attempt at a practical a...

Typomorphic features of placer gold from alluvial deposits of the Bolshaya Kuonamka river basin, draining Eastern framing of the Anabar massif are studied in order to identify association types of primary sources and places, promising for their discovery. Based on identified indicators of gold, it is defined that, ore manifestations of low-sulfide gold-quartz association are the main primary sources of gold-bearing placers. Identification of palladium gold in association with platinoids, as well as its intergrowth...

During the process of conceptual designing of earthmoving or construction boom type machine we have must ensure that it is applicable in practice, meaning stable. Unfortunately, not every time is design of upper structure of such a machine ideal in consideration of position of centre of gravity and that is the reason why are stabilizing outriggers usually attached. This article talks about possibilities of use various schematic drafts of stabilizing outriggers for earthmoving and construction machines on the wheel...

For generalized inversion, non L2-norm inversions have been widely used in geophysical inversion to obtain sharp and blocky models. However, problems such as the boundary of anomaly body obtained by inversion is not clear enough and the recovered residual susceptibility value is far less than or greater than the true susceptibility generally exist. In this paper a new 3D magnetic inversion approach based on residual node susceptibility is proposed. The residual node susceptibility model comes from residual block s...

Coal mining causes undesirable terrain subsidence due to caving in of the overlying rocks into the already excavated space. Subsidence deforms the terrain, damages structures on the surface and water flows, which results in the formation of inaccessible wetlands and swamps, and these areas need to be reclaimed. The problem of large flooded areas as a result of mining activities also concerns an area known as пїЅKozinecпїЅ, which is located between KarvinпїЅ and Doubrava in the Czech Republic. That territory has lo...

The major changes occurred in Romanian mining industry imposed by the transition to the market economy, concentration of extraction to fewer output units in deeper seams, the high gas emission rates and coal rank, other current specific trends requires new methods to produce the optimum design and operation of a safe and economic methane drainage system. Under the circumstances, the paper describes a mathematical model together with a computer-aided optimization strategy to assist the analysis of the differences b...

Testing and certification of explosion-proof electrical equipment required for product conformity assessment are extremely important, taking into account the unexpected hazard of explosion occurrence due to potentially explosive atmospheres generated by mixtures of air-gas/dust. The explosion risk has to be minimized in order to ensure the health and safety of people and for preventing material damages. The new European Directive which regulates the protection to explosion field is the ATEX Directive 2014/34/EU wh...

Changes of damage to the belt core that are not controlled during the exploitation can lead to dangerous accumulation of the defects (strains) in the cross cross-section. It can lead to serious weakness and even rupture of the belt. Early detection of the mic rodamage of the covers and evaluation of the increase speed of the damage allows the user to plan maintenance more precisely. Furthermore, it allows more effective cost management when conveyor belt maintenance is scheduled. In this paper, geometric data o f ...

Degraded post-mining areas have considerable potential for redevelopment. They are usually located in attractive urban areas and have convenient road and rail links to the rest of the city and other places in the region or country. These areas are often equipped with power, water and sewage systems. The redevelopment of these sites could take place in many different directions. They can be used to carry out production, service, commercial, residential and leisure activities. However, the unstabilized legal situati...

Conditions of the microclimate prevailing in mine workings are one of the most important factors influencing on the comfort and safety of the working mine crews. This climate depends on parameters of the ventilated air stream and conditions prevailing in these workings. Parameters having the most important influence on the conditions of microclimate are temperature of the air and rock mass, humidity, velocity of air stream and average temperature of radiation of wall surface of the working. Nowadays, due to the la...

The paper begins with the idea that in a large energy enterprise, formed by merging several energy companies with a mining company, the organizational culture is the key to success. The paper underlines the close connection between the organizational culture and the enterprise efficiency. The organizational culture supports the economic and social efficiency, the adaptability in the competitive context and the company which has a strong organizational culture may be saved from the consequences of unfavorable econo...

Rosia Montana deposit is made up of several ore bodies; the natural factors are characteristics of each ore body. The deposit is accompanied by an extensive area of hydrothermal alteration, whose distribution has a complex character. Fast alteration and humidity were one of the factors that have been taken into account in order to achieve quarry. The quarry platform has reached at the level of the upper bottoms in the breccia area, which involves passing to the exploitation of the reserves included in these pillar...

The article describes the chosen Japanese production and maintenance management philosophies, such as Lean Management, kazien and TPM. Japanese approaches to the process of work organizing and work planning, workplace preparing, tasks, duties and responsibilities turn out to be the most effective and the most efficient in the world. The practical application of these philosophies entails achieving the measurable benefits by the companies that use them. The basis of these philosophies is the elimination of all kind...

Since the beginning of deep mining for the acquisition of minerals or driving galleries, later tunnels, man has faced the problem connected with draining used and polluted air (the so-called mine air), and transport of fresh air to the workplace. Since time immemorial, mine air has influenced and prevented the work of miners and drifters, as well as of the mechanized technology. The most significant factors of air pollution include exhaust fumes of mechanisms used in the performance of work, blasting fumes and, ob...

The exploitation of copper ore deposits in Polish underground mines is performed primarily by the use of blasting technology which seems to be relatively well suited to the hardness of the local rocks and to local mining and geological conditions. Blasting works are also recognized as an active method of seismic events prevention, conducted as group strain-release blasting within potentially instable main roof strata and in pillars. A notable number of recorded dynamic events can be clearly explained by the blasti...

According Act No. 157/2009 Coll., on mining waste management, the Czech Geological Survey carried out a project of the Operational Programme Environment in 2010пїЅ2012. The project was entitled пїЅInvestigation of closed and abandoned mining waste facilities posing a serious threat to the environment or human healthпїЅ. The aim was to create an inventory of hazardous mining waste facilities and to develop a methodology for their assessment. In the Czech Republic, 300 potentially hazardous mining waste sites were i...

A conveyor belt in regular operation is negatively influenced by a number of factors. This negative influence is the result of coming in direct contact with the transported material, which frequently causes serious damage and reduces belt lifetime. The scale and type of this damage depends on many factors, such as a beltпїЅs physical and mechanical properties and its design. The properties of the transported material and the design of the feed point are also of considerable importance [4]. When the damage is cause...

This paperwork is based on the data emerged from a conducted research related to a moisture influence on ignition sensitivity of air-methane gas mixture. For the purpose of this demarche it were used method of signal processing approach as it is data filtering and mathematical transform of the experimental data. In the first part of the paper, it was presented the spark test apparatus used for the experimentation and the results of the experimental data obtained during the tests with mixture air-methane and moistu...