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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 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 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 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.

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...

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...

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...

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 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...

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...

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...

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 (...

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...

Trepça mine in Stantërg during its activities of exploitation periods divides this process in three stages of exploitati on, where in the first stage there are old exploitations of levels from 830m and 610m, and the way of exploitation method, dimensions of backbones and securing plates has been change d as a result of determination of height of floor-horizons between them. The heights of 30m and the angle of small fall allows this method of exploitation to be more favourable and secure. Securing backbones, are ...

Mining bodies that lay in the depth of Earth’ s core always appear as irregular bodies in different geological- mining circumstances. Mine “Trepça” in Stanterg since the beginning of its work in 1930 up to now has applied several exploitation methods of mining bodies, and one of these methods is the so called Frontal Method. This method is applied in cases when the ore body has small sizes in length from 30m and the fall angle up to 30º. During the app lication of this method, the securing backbones have b...

All Kosovo mines have undergone the different declines and degradations in transition period. Some of the underground mines have also undergone the flooding under water as a result first of the war in Kosova, because of the damage of dewatering system, the lack of investments and disorganisation of mine’s management, undefinition of the ownership status of mines, the interference of peoples interest, the ownership status, the resource of no one without any care at all, th e transfer from the monist system to the...

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...

Contribution notifies of the variant solutions of the recovery of consequences of chemical uranium mining in the Czech Republic in the Straz pod Ralskem region. Remediation is realized by a state company DIAMO. In the chemical extraction period over four million tons of sulf uric acid and other chemical s were injected into the ground, whereas approximately 370 million cubic meters of groundwater were contaminated. Currently, the contaminated water is pumped from the underground to the surface and it leads to liqu...

Efficient protection and construction of engine ering and other struct ures in seismically active areas is a series of contradictions, where an optimum solution must be found, which does not comprise a compromise at the expense of safety and security of the people, and which minimizes damage of property. Along with the increase of the needs for energy, the need for open pit mining production increases, which is related to the mass blasting with incr easing quantities of explosive, and nearing to the population cen...

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 ...

Ground vibrations arising from excavation with blasting is one of the environmental problems in mining industry. The prediction of ground vibrations and the realization of controlled blasting based on this prediction have a great importance in order to minimize the environmental effects of blasting. The purpose of this study is to analyze the ground vibrations induced by blasting at Akyol Quarry which selected as a test site after the determination of the geomechanical properties of the rock mass with a computer s...

We propose a device which produces a high density cloud of spray that is consisted mostly of water micro droplets. The cloud automatically occurs when an electromagnetic pulse or/and shock wave from a close explosion matches the device. The ratio of absorbed energy of the dangerous shock wave depends on the density of the cloud and on its spreading speed as well as on the size and the mass of micro droplets. We have developed a mathematical model of physical processes in the Absorber. Numerical simulations show sa...

The paper presents the evaluation of mine disasters statistics with particular reference to aerological disasters which took place in Polish coal mines from 1945 to 2008. These disasters concern the events which the death of five or more miners working in the mine underground. They were caused by: breakout or outflow of carbon dioxide, methane explosion, tremors and roof falls, explosion of coal dust, fires, heat strokes, water outflows or breakdown of mine equipment. The special attention was paid to fire prevent...

Abrasive waterjet technology (AWJ) is one of the fastest growing machining processes. It is environmentally friendly, can machine almost any engineering materials. It has received considerable attention from various industries due to its beneficial characteristics. Compared with traditional and most non traditional machining technologies, AWJ exhibits a high potential in the field of the shape machining of hard or brittle materials such as ceramics, glass and rocks. The present study investigates the machinability...

Bauxite mineralizations of Seydisehir reside in western Taurides, in Konya region. Mesozoic limestones form the base of local stratigraphy. On top of these Eocene aged limestones and flysch units have precipitated. Allochthonous Paleozoic aged limestones of Hadim nappe units have moved on top of all these units. Formations of the region have undergone extensive tectonic activity. Bauxite mineralizations in the region are associated with Mesozoic limestones. They are located in karst spaces of limestones. These spa...

GIS enables spatial or nonspatial data to be transferred or stored into computers and various spatial, numerical, verbal analysis to be made by using this data prepared for this purpose. Although GIS has been used immersely in many fields, it hasn’t been widely used in mining. The aim of this study is to show the applicability of GIS in mining and its benefits for this field. With the help of the software developed in the scope of this study, it is aimed to plan the maps belonging to area of mining licence in th...

The project No 17005 (2008-2010) is a correlation Subotinac locality in the global wine and gave immense larger investigation of Subotinac (The Aleksinac basin) in respect of geological research. This paper is the result of research by the project of the Ministry of Science and Technological Development No 17005 R. Serbia. Papir presented corelation results of previous prospecting and detailed geological study of the basis for a new supplementary geological and chemical-technological research oil shale in the vici...

Basing on physical model of heat exchange between human body and environment, predicted thermal load under the work site parameters, specific for deep mines, was defined in the paper. The relationships included in EN ISO 7933 standard were used for this purpose. Level of heat accumulation, degree of skin moistness, maximum volume of sweat and body dehydration were evaluated. These parameters we used to define the safe time of work under difficult climate conditions. The calculations were made in respect of acclima...

DelPat program makes possible to design of blasting operations and cost estimation with ground vibration analysis arising from blasting. In this study, these applications of DelPat program were used for blasting works in excavation of Boyabat Dam and H.P.P. (Hydroelectric Power Plant) construction and the results were researched extensively. Blasting design was done and the results of planned blasting works and ground vibration measurements were analyzed by use of DelPat. At the end of some shots, 35 events were r...