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A structural analysis on the used in processes of open cast mining formula is made and some functional dependences are deduced. This shows the relation between optimal speed on temporary rail ways and the productivity of mounding excavator – single – bucket and with many buckets.A structural analysis on the used in processes of open cast mining formula is made and some functional dependences are deduced. This shows the relation between optimal speed on temporary rail ways and the productivity of mounding excav...

The flyrock from blasting operations can harm, damage or expose the workers of a particular worksite or the dwellers of a wider area of extractive activities (quarry, mine, construction site) to damage risks; in some cases even death might be caused, too. There are certain and different ideas and theoretical approaches regarding the evaluation of causes and the implementation of flyrock prevention measures to be taken, as well. This implementation, however, in practice requires a more delicate and rather professio...

Paste backfill is composed of a mixture of mine tailings, process and/or fresh water for the desired solid-water consistency and hydraulic binder to ensure a target mechanical resistance. This paper presents some studies undertaken on the strength development and deformation behaviour of paste backfill mixtures made from a Turkish zinc mine tailings. A series of laboratory experiments was conducted to determine the strength and deformation properties of paste mixtures with binder content ranging from 4 to 7 wt\% a...

The transport represents one of the main sides of the mining technological process, the preponderance of the expenses of this activity reported to the expenses for producing a tone of useful mineral substance extracted from the underground reaching almost 40\%. A good transport system presumes to assure a permanent continuity with passive time cycles having minimum values and functioning in well correlated cascade dimensionally and capacitive speaking. It’s obvious that a transport flow is performing if starting...

Nickeliferrous laterite is a source of ferronickel alloy extracted by a pyro-metallurgical process. Laterite deposits found in Greece are mainly secondary depositions and their nickel content is about 1\%. Beneficiation of the run of mine ore is limited to the +1 mm fraction by magnetic or gravitational processes and its effect is rather unsatisfactory due to the insufficient liberation of the nickel bearing minerals. The mineralogical structure of the ore consists mainly of hematite nodules (pissoids) and quartz ...

In this study, diagnostic leaching and ultrafine grinding as pretreatment step ahead of two-stage cyanidation of KaletaЕџ ore were studied to shed light on the refractory characteristics of ore. The overall gold extraction of 93\% was achieved in two-stage cyanidation of ultrafinely ground ore suggesting the presence of readily recoverable gold (74\%) and slowly reacting gold (19\%) in the ore. Diagnostic leaching approach provided information into the cause of the refractoriness of the ore. The findings of diagno...

In this study, flotation concentration of Trabzon-KayabaЕџД± Massive Sulphide ore was investigated. The effects of particle size, reagent concentration (collector and depressant) and agitation speed on the recovery of copper were studied. The results have shown that the ore responded poorly to concentration by flotation with low efficiency of seperation of copper minerals from sphalerite and pyrite. Changing the flotation conditions i.e. decreasing particle size to >99\% passing 38 $\mu$m or increasing the concent...

The influence of temporary rail ways over transporting ability through the mining railway net in open cast mines is researched. A functional relation between optimal speed of temporary ways and the transporting ability is found.

As it is well known, the process of extracting from the underground the reserves of useful mineral substances by using mechanical methods had been extended mainly regarding the energetic coal a series of countries in the period of 1970 ? 1990, that generated many actions of conception and manufacturing of some specific equipments being remarked mainly Germany, England, Poland, ex - countries of Soviet Union, etc. The main idea consists in choosing and correlating dimensionally, capacitive and functionally some com...

The optimization of the coal winning process using different mechanical and alternative cutting techniques using appropried mathematical models is an up to date reserch methodology. In the paper, two kind of such models are presented, first using deterministic analytical relations evaluated by numerical calculus, and the second using Monte-Carlo simulation of the process using experimentally obtained test data to generate random values of intrinsic rock parameters and logic diagram for the functional connections b...

In this material offers mechanical model that builds on the basic technological characteristics of the system rock – frictional pipe anchor bold (FPA). In the presentation, the anchor is divided on the modeling elements. Their size is determined from the physical model that describes combined anchor-rock system work. Key words: mechanical model, system anchor-rock, stress field

An ongoing geologic and geophysical investigation in the deep-water Black Sea, offshore Bulgaria reveals conditions suitable for hydrocarbon accumulations with giant field size potential. This potential lies within the buried offshore extension of the Paleogene Balkanide fold belt and its adjacent Eocene-Oligocene foreland basin, in water depths of 500-1,700 meters. With the benefit of onshore geologic studies and new offshore seismic acquisition and processing, it is possible to recognize and evaluate the basic e...

In this study, diagnostic leaching and ultrafine grinding as pretreatment step ahead of two-stage cyanidation of KaletaЕџ ore were studied to shed light on the refractory characteristics of ore. The overall gold extraction of 93\% was achieved in two-stage cyanidation of ultrafinely ground ore suggesting the presence of readily recoverable gold (74\%) and slowly reacting gold (19\%) in the ore. Diagnostic leaching approach provided information into the cause of the refractoriness of the ore. The findings of diagno...

The paper makes a general presentation of the firedamp resources of the world and the exploiting methods used before, during and after mining activitites. The evaluation of firedamp quantities from the coal bed in exploitation at active mines in Jiu Valley Outgas systems in exploitation at mining units in Jiu Valley and the monitoring of firedamp emissions from these mines Solutions to recovery the firedamp from closing mines Firedamp marketplace – energetic resource for the future.

Results from students’ education in subject “Explosions in Industry” are noted in the protocol. It is towards sector “Education of Bulgarian Citizens” to the Complex Center for Education and Qualification of MGU “St. Ivan Rilski”. There is a short analysis for study plans, programs, way of taking certificate for work with explosives and there are some offers for improving the education quality.

The Sabzevar complex ophiolite including igneous rocks consist of peridotites (lherzolite, dunite and harzburgite), serpentinite, gabbros and a volcanic sequence composed of basalts, andesites, rhyolites and basanites. Based on petrographic observations and geochemical analyses of incompatible trace and rare earth elements, three different types of extrusive rocks have been classified. a: Initial molten originated N-MORB-like basalts, which formed after a LREE depleted magmas, and are petrogenetically related to t...

According to the mineral compositions, paragenesis, relationships and the fluid inclusion microthermometry two stages of skarn alteration within the Rize pluton area have been identified. The first stage (stage I) was characterized by the Spurrite, vesuviavite, wollastonite, magnetite, pyroxene, gehlenite and garnet assemblages at high temperatures ( 750 oC). The second stage (II) occurred at lower temperature ( 500 oC) when the system collapsed, and is characterised by tremolite, low temperature vesuvianite, rust...

For increasing the endurance of bucket wheel excavators’ teeth dipper, used in brown coal open pits from Oltenia, were made theoretic researches and experiments finalized with the accomplishment of new dippers and teeth more reliable and more cheeper, which are used according to mechanic characteristics of brown coal and dead-ground from the working faces.

The idea of underground coal gasification is connected with the name of Mendeleev 120 years ago. But its practical realization starts during the 30th years of the previous century and continues up to now. There is not any technical or technological problem to perform gasification as a method of processing hard household wastes. In combination with recycling of part of the wastes and utilization of gaseous products of gasification for energy production, this method could be very effective and attractive. If we supp...

Temporary rail ways in open cast mines influence by the accepted speed for the trains. They have influence on the most important indicator of heavy mining mechanization – the productivity of excavators – stope and mounding. This problem has been always underestimated because a priori has been accepted the dependence between the accepted speed and productivity. This research proves another type of functional dependence – fraction-lineal.

Mine backfill can be defined as the material or materials used for filling the underground openings created by the mining process in order to establish and retain safe working conditions. In this study, an overview of the current application of mining operations with paste backfill technology has been examined with a case study from an underground copper-zinc mine located in the northeast Turkey. Due to the elimination of the harmful mine tailings obtained from mill processing and hence the reduced rehabilitation ...

The influence of temporary rail ways over transporting ability through the mining railway net in open cast mines is researched. A functional relation between optimal speed of temporary ways and the transporting ability is found.

The Sabzevar ophiolite is a highly dismembered ophiolite complex located along the northern boundary of the Central Iranian Microcontinet (CIM) and is one of the internal groups of ophiolites and colored melange. The area has various lithological units that are the cause of Sabzevar colored melange zone. There are many chromite pods in the area but the high topography and mountainous condition and inability to trace the hidden lenses, many of them are not explored yet. A mathematical- genetic model could be helpfu...

The mine production is an inflex point of industry due to the fact that the work is conducted in an environment with abruptly changing parameters and at great depths, where the laws of physics are valid through their exceptions. Under these conditions, the main controlling factor is the mine-geological and technological information. Its management is the basis of the modern mine production.

The optimal numbers of runs of a train in open cast mine is one of the most important technical indicators, on which the work of rail transport in mines is evaluated. A functional dependence between the optimum number of runs of a train and the accepted speed on temporary rail ways in a mine is deduced.

All the specialists in open cast mines which are equipped with technological railway transport know that the transporting process has underlined optional character. This is based on several factors. One of them is the levels intensity of possibility of transportation process to be done without any exceptions. The report is on the principles, on which the levels of intensity can be defined.

Twelve of the numerous methodological problems are represented. They appear in the development of the automated systems for control of the mine works at open mines; if these problems are not reported the work of the system can be compromised partially of totally. Shortly those problems could be formulated as follows: 1.The mine is not considered like a system; 2.A management of the model; 3.Hierarchy of proposes and limitations; 4.The depot – a solution or a problem; 5.Attention: literally performance; 6.In prob...