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The specific energy consumption is mainly influenced by kinematics and dynamic measures of vertical transport installations as well as by the compatibility of different composing parts and their subcomponents. The optimisation of kinematics and dynamic parameters characterising a transport cycle is decisive considering the energy consumption. Also considering the operation of the vertical transport installations, as well as the character of the variation of kinematics and dynamic parameters during a race, it has b...

Mineral fuels are among the non-renewable natural resources. For this reason, would be addressed in a responsible and rational use. Mineral fuels are among the so called strategic raw materials, the use of which is essential to the national economy and energy security. Raw materials base in Slovakia as regards energy raw materials consists mainly of brown coal, lignite and uranium, part of the oil and natural gas. To determine the prospects for the use it is necessary to know the quantity of reserves and the econo...

Currently mobile mining machines, including primary ones, such as drilling and bolting rigs, or used in underground mining of metal ores, are most commonly driven by internal combustion engines. Due to the large depth of mining, this type of drive provides a number of disadvantages, including a large generation of fumes, heat and noise. The solution to this problem seems to be the use of the electrical battery drives, similarly as is the case in motor vehicles. The article presents the assumptions and boundary 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...

Jiu Valley mining area is one of Romania where currently exploiting a coal deposit, which has important reserves of balance that can ensure beneficiaries' needs (CET Paroseni and CET Mintia) over a period of several decades. Structural changes that have occurred in the Romanian economy since 1989 have generated, but layoffs / redundancies collective personnel reorganization / activity restrictions in the mining units and the closure of some mines with no prospects of viability. All this led to a sharp economic dec...

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 technology of cutting with a plasma arc is today a very advanced solution for thermally cuttable conductive materials. Plasma or also the plasma arc is composed of positively and negatively charged particles, excited and neutral atoms and molecules. As it contains free particles, it is electrically conductive and thus subject to the effects of an electric and magnetic field. This article discusses the use of plasma cutting technology on a CNC machine. The resulting quality of the plasma cutting is determined b...

The paper presents an innovative strain and temperature measurement method using the fibre Bragg grating (FBG) technology to monitor the design and operating safety of selected underground mining machinery and equipment. The system is based on the fibre Bragg grating (FBG) sensors or sensors using the optical time domain reflectometry (Optical Time Domain Reflectometry) technology. The essence of the solution is to introduce FBG sensors into the structure to make them act as its пїЅnervous systemпїЅ. Compared to c...

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...

Nowadays surveying пїЅ geological departments of Polish coal mines conduct forecasts of leverages of underground mining on area and construction works based on J. BialekпїЅs formulas including, among others, distant leverages, reactivation of old workings and mining margin. The objective of this article is the adequacy study of the conducted forecasts of area deformation in this way with relation to real values of deformation indicators confirmed by surveys. For this purpose, an example of a really terminated expl...

The airborne geophysical survey in Kosova is a very important project, which has been conducted during 2006 -2007, according to the terms of references processed by the ICMM. The airborne geophysical survey in Kosova is carried out by the British Geological Survey and the Geological Survey of Finland. The geophysical survey is carried out for three components. There are provided the important data with the images of electromagnetic, magnetic and radiometric components. The ICMM possesses the necessary software, wh...

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...

In the case of this thick and gentle coal seam no.3 of the Jiu Valley coal basin (Romania), the mining methods are by use of the longwall mining technologies with roof control by caving or top coal caving. In this paper, it is presented the analysis of the complex deformations of ground surface, over time, as a consequence of the coal mining in certain mining fields of the basin. Also, it is analysed the ground surface subsidence phenomenon using the CESAR-LCPC finite element code. The modelling is made in the ela...

Selection of optimum support system for tunnels and underground opening is a multi criteria decision making pr oblem. In this paper, first, st ability analysis of access tunnel in gooshfill mine is done, then selection of support system for these tunnels by considering of economical cr iteria and technical criteri a by using ELECTRE method is presented. Criteria that are involved in d ecision making process are: displacement at roof, bottom and side of the tunnel, safe ty factor, cost, labor requirements and appli...

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...

The technogenic deposit “Slag Depot 1“ was formed by many decades dumping with content of significant amounts of copper, gold, silver and other useful components. As the copper percentage in the ore, whic h is now mined at the open pits within RTB Bor Group, is significantly lower than in the technogenic deposit, its mining and reprocessing have started in 2002. Considering that it is a technogenic deposit, a specific technology of its excavation was previously used, and the same is described in this paper, wi...

Basic results of many-years complex geomechanic research experiments carried out in Far Eastern Russian mines and aimed at a problem of rock – burst are given in the paper. Methods and approaches to rock – burst assessment are reported, some regularities of an ultimate - strained rock massif behavior and prognostic criteria of sorting of massif sections to a category of hazard regarding dynamical rock pressure appearances are considered. The paper includes four figures and 13 references.

Cankiri rock salt formation is one of the mo st important rock salt sources of Turkey. Rock salt production in this area is performed by underground room and pillar mining method approximately 150 m under existing t opography. However, pillar dimensions which are used in Cankiri rock salt mine ar e determined by trial and error method. Aim of this study is to create a model which will overlap long and short term rock mechanics analysis results with in-situ stresses and in-situ deformations. By the evaluation of th...

This paper represent a short review of non-metallic resourceses (NMR) on few selected lignite deposits in Kolubara Coal Mines (KCM) and estimate thems potential in material and economic aspects. The further discussions are in preliminary mean and looks like an preliminary case study estimation. The paper is in agrement with the principles of sustainable development and the principles of complete and complex utilisation of mineral resourceses potential of the coal deposits. A timing of open pit works on ’’E’в...

As per Regulation of the Czech Mining Of fice Board No. 435/1992 of Law Digest, as amended, there is a duty to survey any and all mine workings in the national reference system of S-JTSK type. The objective of both connecting and orientation surveys on the earth surface is to identify the end poi nt position for the plummet segment and especially to identify their bearing. Connec ting the horizon in the mine plays a role in transferring the coordinate values from the said plummet segment to the points ensuring the...

The cooper ore reserves of Ro Еџia Poieni deposit (Romania) represents about 40% of the national cooper ore, that importance increasing with the actual rising cooper price on the international market. Deposit mineralization is located within the Fundoaia andesitic ore body and appears mainly on a system of fractures, or as uneven distribution impregnations in andesitic rocks. The mini ng of this cooper deposit began in 1977 and in 1985 reaching about 9 million tonnes of or e capacity and in 1988, 15 million tonnes...

Rubbers used in conveyor belt transport undergo an aging caused by the aggressive character of external environment during their operation. The main changes of conveyor belts due to the aging process appear firs tly on their surface being in an immediate contact with the cargo transported and/or with an ambient air. Chemical changes caused by the aging are reflected in changes of physical properties of belt components such as network density, glass transition temperature Tg and other. Determination of physical pro...

Coal is the most consumed fossil fuel in the world. Determin ation of the thermal properties of coal is a very important matter and it is not straightforward because of the heterogeneous structure of the coal. The short and elementary analysis results of coals with different carbonization de grees are different. The mineral composition of a coal also affects the thermal behavior. To detect thermal properties of co als, thermal analysis devices are generally used in many widespread methods. The most widely used met...

The inadequate comprehension of specific haza rds, mainly related to their nature and magnitude, have lead in the past to the occurrence of several catastrophic events in the Romanian mining industry. The mining industry, like other major global industries, must consider and manage risks to business objectives, to remain successful. Management of risks requires a proactive, systematic approach, applied when key decisions are being made across the life cycle of the industry, from exploration to mine closure. Presen...

We present the results of precious metals leaching from stubborn sulphidic silver-and- gold-containing ore of Kazakhstani deposit Kunisty by complex cyanide в€’thiosulphate solutions in comparison with separate cyanide and thiosulphate solutions in the model and experimental conditions. It is establis hed, that in a range of investigated concentrations 0,03 - 0,1 M, application of complex cyanide в€’thiosulphate solutions leads to change of oxidation-reduction potential of the solutions by 50Г·200 mV. The degree o...

Coal mining trucks is failure in accordance with many reasons. As, the size and complexity of trucks conti nue to increase, the equipment failures become ever more important. In this study, maintenance and re pair durations for coal mining trucks are examined by using factor analysis and The Kolmogorov-Smirnov test for two independent samples techniques. These techniques are applied to dataset obtained by six different trucks working in coal mining. As the result of these methods, it was determined that there are ...

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 ...

Methods for gas extraction are currently ranked among clean coal technology. Coal gas is a normal part of coal deposits a nd its mining reduces methane emissions. Underground coal gasification is a non-traditional mining method that also allows use of coal deposits which are not possible to be mined by traditional methods. These technologies bring both positive and negative aspects aff ecting the environment. This contribution is covering the influence of gas extraction from coal deposits on the environment accomp...

In the Jiu Valley coal basin (Romania), fr om over 2 thousand million tonnes of balance reserve, more than 60% are involved in the bituminous coal seams no.3 and no.5, which ensure 90% of the coal output of the entire basin. The thick coal seams no.3 is mined in slices with longwall mining system and roof control by caving. Because of the short mining panels, often under 300-400m, the star ting costs of mining panels become very important at the entire panel coal reserves. Th erefore, in this paper there are prese...

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....

As a result of mining and quarrying is the exploitation of the landscape (e.g., mine depression or heaps as results of underground mining, or change in landscape due to opencast mining). Restoration of affected landscape is necessary in accordance with current legislation so as to allow its continued use. There are a number of procedures, methods and solutions for reclamation. The aim of our work was to design the information system which would provide ba sis for planning and de cision making about process and met...

For centuries formation of coexistance of two cultures on interface of Western and Central Europe, Germanic and Slavonic, in olden times disturbing clashes of noble families, was in recent hist ory seriously scarred by First World War and subsequent solution of their reasons. Coexistance in the Euroregion Ore Mountains, how is this area called, is in recent years renovated of various exchange of cultural an d sports relations, partnership of towns. Example of this and the most considerable cooperation is in saving...

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...

As is shown in the paper, Russia and its Far Eastern region (RFE) possess large amounts of mineral wealth, comparable to th at of China, USA, Australia, Canada and other major mineral producing countries. The same can be said with respect to the production of mineral commodities, including highly valuable ones. Unfortunately, country's and region's mineral potentials are insufficiently geologically explored and are not used to their full capacity. Presumably, the situation can be s ubstantially corrected in positi...

Knowledge of physical, mainly mechanical, properties of conveyor belt rubbers belongs to important preconditions of trouble-free op eration of conveyor belt transportation. Mechanical nature of rubber materials used in belt transportation have among others an immediate effect on the friction between rubber layers of a conveyor belt and a driving drum and/or on the total power consumption. This knowledge is relevant not only in the case of new belts where it help s their optimal selection with respect to the nature...

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...

The technological process applied to coal opencast mines is based mainly on a continuous technology: an excavator, long-di stance belt transport and if need be, a spreader. These extensive systems are controll ed remotely from central control stations. For some purposes, the visualization of the technological process using SCADA/HMI systems is insufficient. On the basis of th is research, procedures for the creation of virtual models of technology, mining process and opencast mine were proposed. Virtual models are...

The phenomenon of displacement and deformation of the surface land, continues to present a wide interest in th e implications of environmen tal problems and protection of existing construction area. The researches in this direction have led to the conclusion that the observations made in the areas affected by underground mining can be done short-term forecasts, medium and long forecasts about the phenomenon analyzed. These forecasts have been particularly important in the sense that future studies can be made for ...

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...

In the paper it is demonstrated that due to mineral resources specificity many mining industries do not strictly comply with clas sical liberal economic model and are faced with the necessity to combine mechanisms of both market and planned economic models. Besides, it is shown that various co mbinations of two leading economic models are present in countries throughout the World. With the help of a generalized structural model, both similarities a nd diversities are specified, which exist between mineral resource...

Coal is one of the main energy sources in condition of Slovak republic. During process of gasification there is rising coal gas that presents natural part of every coal bush. Methane presents its significant element. One of the technologies for ga s obtaining in situ is also underground coal gasification – UCG. Technologies for gas obtaining from the coal layer are considered as “clean coal technologies.” Despite of their using there can be contamination of every element of the living environment. By not per...

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...

Energetic theory of disintegration repres ents the starting point for the search for optimum of rock cutting, as it issues from the instantaneous advance rate of the indentor, specific cutting energy (am ount of energy used for cutting of a unit volume of rock) depending of applied thrust. Search for optimum on experimental drilling stand using the optimization met hods is impossible due to technological limitations (limited area for optimum search due to limited rock sample length, duration of experiment, possibl...

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 (...