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Conveyor belt loop operates in a system comprising a series of belt segments and the splices between them. Splices are the weakest parts of a loop. Depending on the splicing technology, the spliceпїЅs strength, durability and reliability may vary significantly. Vulcanized splices offer the highest strength and durability. In the case of steel cord belts, such splices are practically the only technology available. In the case of textile belts, adhesive and mechanical splices may also be used. Although mechanical sp...

The authors have revealed particularities in destruction of the rock mass by the system of borehole charges and substantiated the least seismic hazardous blasting schemes which allow decreasing out-contour disturbances and providing more qualitative crushing of rock mass. It has been shown that for the boreholes with 250 mm diameter the least seismic hazardous blasting scheme is one with borehole line placed at the angle of 105пїЅ to the bench wall. At that, the stress level in the out-contour rock mass decreases ...

This paper presents results for a research of the possibility of applying the combined methods of mining in construction of the underground premises in coal mines in the Republic of Serbia. The purpose of this study is to process the application and effects of combined (standard) methods of a pit remises construction through coal with a goal to find new technology of construction which will result in more productive and rational ways of their building. This study includes the analysis of the construction of pit pr...

Healthy and safe working conditions underground, especially in areas with potentially explosive atmospheres depend mainly on the method of operation and management of the ventilation system. For underground extraction of coal are running a complex network mining vertical, horizontal and inclined role extraction, transportation and evacuation the surface. Associated system of mining works has the air network to ensure the oxygen necessary for workers, diluting explosive gases and toxic substances and preparations t...

A switch to combined automobile-conveyor transport is offered, i.e. cyclical and continuous method, at an early stage of the development of steeply falling deposits, based on usage of advantages of the safe intensive development of working zones along the steep open pit edges at a number of open pit mines on the territory of Kazakhstan. It is possible to shift from traditional approaches of cutting a new pit banks by advance of the cut trench with the minimum dimensions on the round-shaped open-pit fields. Decreas...

When it comes to workplaces characterized by a high degree of hazard and liability, such as mine intervention and rescue in major risk environments the most important element is the convergence of the skills required by job and skills of the individual, this being the guarantee of successful vocational selection. Along with psychological selection, training / retraining and physical training in conditions as close as possible to the reality of future interventions, under the action of stress factors that cause neg...

Uranium mining is the first step in the nuclear fuel cycle to produce energy. In the nuclear fuel cycle, main steps are; Mining / Milling, Conversion, Enrichment, Nuclear Fuel Fabrication, Reactors, Reprocessing of the spent fuel and Waste Management. In the first step, there are three main methods for uranium ore extraction. These are; Open Pit Mining, Underground Mining and In-Situ leaching (ISL/Lixiviation). All forms of mining methods create health risks for people and hazard for the environment. In this study...

The article deals with the treatment of terrain and the following forestry reclamation in the Erv?nice area situated near the city Most at the foot hills of Ore Mountains. It considers the impal of using secondary energy products for the reclamation of this previously mined area on ground water, surfac ewater, air and noise. The area had previously been used as sands and gravel waste disposal and in the last years efore there clamation there had been some natural restoration of the biotopes on the brought sands ub...

According to the European Commission, critical raw materials are defined as пїЅthose which display a particularly high risk of supply shortage in the next 10 years and which are particularly important for the value chainпїЅ. Therefore, when considering a raw material criticality, two main parameters are taken into account: its economic importance and supply risk. Technologies which a decade ago were considered high tech became current today, and raw materials once considered as minor, have gained importance. Parti...

The article summarised course of activities in trachyandezit (Latit) quarry (tephrite) in Bra?any location starting from mining working permit phase until termination of activities and subsequent redevelopment and reclamation of quarry residual pit. Redevelopment and reclamation of territory after mining is one of the main activities of Severo?eskпїЅ doly a.s.The paper provides data on the Bra?any opencast mine, namely the geography, environmental situation, climatic, hydrologic, geological and hydro-geological co...

The scientific paper proposed deals with the reliability analysis of the average usage time of the brake pads as components of the braking system of the industrial front-end loader and transporter machinery used in mining operations in Romania. The research was conducted at the request of several mining companies in Romania, that are using the front-end loader and transporter machinery in their daily operations. The study is based on the empirical information and the preliminary reliability results that were recor...

Non-electrical equipment has been used for over 150 years in industries in which likely to occur a potentially explosive atmospheres and a great deal of experience has been gained in the application of protective measures for reducing the risk of ignition of such atmospheres to an acceptably safety level. For using non-electrical equipment in potentially explosive atmospheres, it became necessary to produce ignition protection concept standards which clearly defined these protective measures and incorporated the e...

The Cukar 2 east ore body represents the latest explored ore body within the Mucim Mine with possibilities to enter exploitation stage in near fututre. Calculated ore-bearing coefficient in the Cukar 2 east ore body was 0.40%, meaning that within the ore body boundaries 60% of mass is not mineralized somehow, which is compatible with remaining three ore bodies within the Buchim porphyry copper mine. The calculated value of variation coefficient (V) has shown value of 71.39% that is in the range of 43-100%, which d...

The solving of European Commission (Research Fund for Coal and Steel) research project пїЅBucket wheel excavators operating under difficult mining conditions including unmineable inclusions and geological structures with excessive mining resistanceпїЅ is under way from 2015 to 2018. The Brown Coal Research Institute j.s.c. is a member of the research team comprising Czech, Polish, Romanian and Greek technical universities and companies. The main task of the year 2016 was the realisation of the three long term meas...

The paper presents the investigation results of rock mass state change regularities taking into account geological and mining factors by complex methods. The authors consider complexing of results from the cluster analysis of seismic events with numerical modelling of stress state in the rock mass on a case study of the Yukspor deposit (the Khibiny rock massif, Murmansk region, Russia). The time and dimensional analysis of the Yukspor depositпїЅs seismic regime was performed. The cluster groups of seismic events w...

Drilling by the submersible drilling hammer is one of the progressive technologies in drilling of boreholes and it is currently being widely applied method for the drilling works. Use of the submersible hammers disposed in the borehole - drilling directly above the drilling tool - entails number of advantages. The most important is the energy loss prevention. Submersible drilling hammers are gradually and successfully replacing the surface hammers, which have been widely used for many years in Slovakia and in the ...

A starting point for roadheader robotisation (understood as a fully autonomous machine) is to automate the cutting process, which is the basic working process carried out by such machines. In case of boomпїЅtype roadheaders, it consists in automatic control of the movement of cutting heads to ensure that the face surface can be worked with optimum process parameters. This will guarantee high drilling efficiency (drilling advancement) and lower energy consumption, reduced dynamic loads and elimination of overloads....

The paper deals with the theoretical and practical analysis of the influence that the cutting direction of the bucket wheel excavator has on the digging forces acting on the wheel. Usually, when the terrace cut technology is applied, the bucket wheel of the excavator cuts vertical chips where mainly the perpendicular to stratification digging method is predominant. All the laboratory trials - done on the test rig - were conducted mainly for this type of vertical chip cutting. In cases when the drop cut method is a...

Jiu Valley represents one of the most important areas for coal mining in Romania, thus industrial development has generated a high level of health and safety at work issues. At work places in mining industry, the staff of the woodworking workshops is exposed to various concentrations of dust, possibly leading, in time, to occupational illnesses. Thus, wood processed in mining unitsпїЅ workshops is utilized for temporary support of coal faces, wrapping underground mining, insulation dams, ventilation doors, etc. Th...

This paper presents a technical solution proposed for the mining drilling equipment command system, used for digging the horizontal mining works. The manufacturing industry of mining machinery in Romania and from different countries achieved a wide range of equipment for digging the horizontal mining works. As a result of the activity undertaken by a research team from the University of Petrosani, the drilling equipmentпїЅs with one manipulator arm (IMP-1) and two manipulator arms (IMP-2) were designed and constru...

Evaluation of explosion-proof protected electrical equipment in scope of certification is extremely important considering the risk of explosion that has to be minimized in order to ensure life safety and health of workers and to prevent damaging of property and the environment, as well as free movement of goods when they meet the essential safety requirements at European level. The purpose of this paper is to present the tests carried out on the cable entries with type of protection increased safety and flameproof...

In the Czech Republic, the production of energy using fossil fuels - particularly coal - is still a major proportion of total production. The energy sector is and will remain one of the most important areas of the Czech economy, ensuring supply of electricity and heat to the population and industrial enterprises. In the power and heating plants is burned primarily domestic brown coal mined in opencast mines in the north-western part of the Czech Republic, namely, Usti Region. For combustion of biomass in the Czech...

The performances of the excavation machines depend largely on the tool and overall machine characteristics and on the other hand on physical mechanical characteristics of the excavated rock. There were more theories based on analytical deductions to explain the main cutting parameters on the basis of basic physical mechanical properties of the excavated rock. In this paper we use a new methodology, based on reliable laboratory data, which make possible to obtain correlation and regression formulas in order to pred...

Discussed are analyses and studies of an innovative method for managing active mining impact on future urban areas. Taking into consideration legal, methodological, engineering, economic, environmental, and social aspects, the solution represents an interdisciplinary attempt to address active mining damage problems. The examination follows a number of theoretical and practical analyses in addition to standard, numerical, and statistical calculations, as well as econometric models based on case studies and EU guide...

The use of pneumatic energy in industry as well as in the tertiary system is quite frequent representing 10% of the industrial electricity consumption in the European Union, the life span of compressors being relatively long, namely between 14 and 16 years depending on the installed power. Although the compressed air demand of a coal mine is covered by performant compressors manufactured by well-known producers there still are multiple possibilities to increase their energetic efficiency. The working method is con...

The article deals with the structural design of the test equipment for analysis of coatings for hose conveyor belt conveyors. Processed list of existing test facilities in the world. Currently, there are various devices for testing materials using a bi-axial tension. The measuring device of its own production to measure axial forces in the conveyor belt, pipe conveyor is also the Technical University of Kosice. On it is possible to perform various tests conveyor belts by means of which the various measurements and...

The result of the experimental and analytical researches for the appointment of underground excavations, considering the interdependence with the type of rocks met, the working conditions and the safety of the supports have highlighted that the rational use of the actual types of supports, the improvement of the constructive parameters and the design of new types, as a unitary system, needs to be justified taking into account the study of the mechanism of the interaction. The analyses carried out for the rock cond...

The purpose of the paper is inventarization, mapping and valorization of coal mining waste dumps, which occur in the area of Gliwice city (southern Poland, NW part of USCB), for the needs of reclamation and management of examined objects and defining potential recovery of coal from the dumps. Valorization of post-mining waste dumps has been done using original methodology, considering problems of reclamation, management, accessibility of the dumps as well as environmental hazards. On three valorized post-mining wa...

Processing of copper ore strongly depends on its parameters, therefore the more accurate identification of them should improve the process efficiency. The ore exploited in the KGHM underground mines in Poland is among the most difficult for processing, mostly due to its differentiated lithological compound. It can be identified at mining faces but on the way to processing plants through the complex transportation system consisting of trucks, sectional and main belt conveyors and ore bunkers, the portions of ore ha...

The primary requirement for landscape regeneration affected by mining in addition to restoration of functional use is also the permanent sustainability of landscape. The paper deals with the alternative po ssibilities of using redevelopm ent procedures for general restoration of the landscape, also principles of using spontaneous succession, managed succession, forest and non-forest reclamation (including the recovery of the residential areas) on the basis of ecological and land-technical values and potential of l...

The contribution focuses on the technological possibilities of large-capacity extraction, transport and stacking of loose material. It is based on the actual condition of the continuous-operation equipment deployed at large pit quarries. The technical and performance parameters of this equipment, well-tried in practice, were used for modelling the option of replacing it with discontinuous-operation equipment, which has unique performance parameters compared wi th European standards. The key objective is to compare...

The vast territory of Bince region is loca ted in the Viti locality in the SW part of Kosovo, in between Kacaniku Gorge, Morava of Bince Valley and Zhegra Valley. It is characterized by a broad variety of lithology and numerous mineral showings of Cu, Pb, Zn and Fe. Geological setting: Paleozoic shale (Sbm), with marble and quartzite (M, Q), the series of Upper Cretaceous (Cr 2) flysch, Lower Oligocene (Ol 2) volcanogenic-sedimentary series, middle Miocene (M2) sediments, as well as by relatively widespread deposi...

Underground coal mines explosions generally arise from the inflammation of a methane/air mixture. This explosion can also generate a subsequent coal dust explosion. Traditionally such explosions have being fought eliminating one or several of the factors needed by the explosion to take place. Although several preventive measures are taken to prevent explosions, other measures should be considered to reduce the effects or even to extinguish the flame front. Unlike other protection methods that remove one or two of ...

The shape and geometry of bucket edge, edge and tooth material have a key influence on wheel excavator mining processes efficien cy and power consumption. The frequent change of cutting members due to their wear or break in increases mining process costs, shortens excavator operation time which mean s lower efficiency of the technological complex (TC). Every wear means a change of shape, geometry, eventually material properties of cutting members, but the incr eased power consumption of the mining process as well....

The main objective of geochemical mapping is to recognize the promising areas for the semi-detailed exploration in next steps of geochemical exploration. To reach the goal the thresholds value of each interested elem ent within the geochemical sample should be determined at the prelimin ary step. At the present article , it is attempted to use the raw geochemical data after pre-processing to distinguish the prom ising area within the Khusf 1:50000 sheets which is located at 35 km west of Birjand at the south khora...

Many researches have been carried out in field of “Roof rock behavior in coal mines", most of them concentrated on mines devel opment networks; but a less attention have been paid to assessment and classification of roof strata behavior over long wall coal mining panels. In this paper, It has been a ttentioned to roof strata behavior over long wall coal mining panels in East Alborz coal mines. Intens ive field work and laboratory analyses that discuses the influence of various parameters on roof rock behavior of...

Coal mining is connected with many burdens, which affect mostly the safety of mining. One of the most serious problems is exhalation of methane to the mine air. This Paper describes methods used for degassing in Czech Republic’s underground coal mines. Authors deal with new options and new trends in mainta ining security by the means of degassing drill holes. There are two main methods Czech Republic used to prevent accumulation of the Methane gas in gaseous mines. The first method is sufficiently effective vent...

Self-ignition processes are a serious probl em in brown coal mining and depositing. Infusions and following fires are frequent events in open pit brown coal mines with seams influenced with previous underg round mining, homogenisation and other deposits, and on stock-piles of power and heat stations and industrial plants combusting coals as well. The objectives of the project from the ALFA programme No. TA01020351 are presented in this article. The project solves a research, development, and verification of a comp...

The open pit Veliki Krivelj is a copper mine which operates within RTB Bor Group in Serbia. In 1998 a combined haulage system involving the initial dump truck haulage, crusher, belt conveyor and a boom spreader for waste disposal was designed and installed in order to reduce the costs on overburden removal. The designed productivity of the system is 4 700 t/h and it will be fully operational in the next few weeks. Up to date it has been capable of achieving maximal 50% of this productivity because only one of two ...

This paper gives some information about risk management and its significance for financing project in mining industry. The projects in mini ng industry are very exacting for financial sources. By the obtaining of financial sources must be accepted kinds of financing. In the concrete mining company we were determining, which kind of financing is possible to use to finance mini ng projects with acceptance of risk. With the selection of the form of financing are conn ecting risks, that we are analyzing and we were pr...

The aim of this paper is to develop a methodology for predicting the potential of future drilling, not merely on average but more specifically as a function of the grades obtained in the drilling in Chadormalu Ir on ore deposit. In most cases additional samples are collected to reduce the overall unc ertainty on the estimation. To do this, the GET function method is used to find the bore hole locations that are more sensitive in reducing the local and global uncertainty than others. This function considers the Gra...

Investment in the mine scope is one of the most risk able fields. In the new management skills, risk management is a ve ry important feature. During of the execution of a mine project, the variation of each effective factor can affect on the execution, production and efficiency, therefore a mining project ma nager must be knowledge about of any effective parameter such as Annual productivity, annual benefit, annual cost and exploitation time, in project The net present value (NPV) is one of the most important meth...

Sorkhe-Dizaj iron oxide - apatite deposit is located within the Cenozoic Tarom volcano- plutonic belt in southeast of Zanjan, northwest Iran. The oldest units at the Sorkhe-Dizaj area are of Eocene age including trachyte, trachyandesite and andesitic tuffs intruded by quartz-monzonite, monzonite and granite plutons of Upper Eocene-Oligocene. The syn- to post-orogenic island arc magmatism and th e plutonic rocks show characteristics of I- type granites. Mineralization in the area is divided into th ree main zones (...

The paper deals with verification of the sl udge stabilization from retention tanks by using modified cellulose fibers. Verifica tion of the method was implemented through laboratory tests and field test. Laboratory te st take place in VUHU a.s. Most and field test was performed at the quarry Ji Е™Г­, Sokolov coal company, a.s. legal successor. Stabilization took place in order to allow extr action of sludge from retention reservoirs. These reservoirs are build for longer time period and must be cleaned due mainta...

Public Enterprise Elektroprivre da Srbije (EPS - Electric Power Industry of Serbia), the dominant electricity producer in Serbia, is a 100% state-owned public company. The Kolubara Mining Basin (MB Kolubara) with its open cast mines is one of 11 subsidiaries of EPS. In accordance with the Serbian Energy Strategy by 2015, one of the EPS priorities is a modernization and improvement of the efficien cy of EPS' coal mining operations at the Kolubara basin and significantly improvement the quality and uniformity of the...

This paper is focused on the sulphur and su lphur forms distribution in the Antonin coal seam at Jiri and Druzba open-cast mines in the North Bohemian brown coal basin, in the Czech Republic. Briefly describes the basic geological structure of the area, deals with sulphur forms, sulphur genesis, chemism, coal sampling and analysis from the exploration boreholes. Overall 32 coal samples were precisely analyzed. The results of this analysis were used for the construc tion of the graphic outputs. Based on these resul...

A comprehensive review of published books and articles shows that discontinuities, especially joints within coal-bearing depos its are important features that must be considered during mine planning and desi gn. Less attention has been paid to orientations of joint sets and other disc ontinuities relative to mining face in proposed rock mass classification systems. In fact the structural competence of mine roof rock is determined primarily by the discontinuities that weaken the rock fabric. In this paper the effec...

The objective of mine closure is to prev ent or minimize long-term environmental damage, and to create a self-sustaining natural ecosystem or other land use based on an agreed set of objectives. The Romanian mine closure legislation s hould be enforced in the coming years for taking best follow up actions and management of post mining closure. The mine closure is a process which should begi ns during the pre-feasibility phase of a project and continues through operations to lease relinquishment. The closure of min...

The Chah Zard Ag–Au epithermal deposit is located within an a ndesitic to rhyolitic volcanic complex in central part of Urumieh–Dokhtar Magmatic Arc (UDMA), west– central Iran. The deposit is formed in breccia bodies dominantly hosted by rhyolite porphyries. Geological field relationships s how that epithermal mineralization occurred in close association with a phreatomagmatic fracturing event, being localized in breccia cements, and formed as disseminated sulfides in the matrix of the more permeable breccia...

Costs are present in many daily decisions they take managers from lower hierarchical levels, but especially importa nt for strategic decision taken at top management level. The very adoption of certain strategies fo r the enterprise is based on analytical considerations which require methods of ec onomic and financial evaluation of projects, methods that can not be imagined outside costs. Allocation of resources to the enterprise are based on estimated costs, just as they and replacement of assets. Computation of ...