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Used the specialized software solution regarding to the thermochemical facilities, we can predict detonation (e.g. detonation velocity, pressure, energy, heat end temperature, etc.) and combustion (e.g. specific impulse, force, pressure, etc.) performance of energetic materials. The calculation of detonation parameters is based on the chemical equilibrium steady-state model of detonation. The equilibrium composition of detonation and combustion products is calculated by applying modified White, Johnson, and Dantzi...

The transition to mining benches with transverse panels from top to bottom within the boundaries of steeply inclined layers does not allow transforming the results of mininggeometric analysis sequentially for each individual stage of mining into a calendar schedule of mining operations. Therefore, a model is offered for converting the results of mining-geometric analysis into a calendar schedule of mining operations with sequential mining of benches from top to bottom using phased volumes of overburden rocks and o...

The Alto do Sobrido and Ribeiro da Serra Mines, are two antimony-gold mines located in Gondomar, Portugal, and are part of the Durico-Beirao Mining District (DBMD). In this work, we use four geophysical methods, such as gravity, radiometry, magnetic and electromagnetic, to improve the knowledge about these mineralizations and the lithologies and structures associated with them. These four methods allowed us to study these mineralizations through different physical properties. The gravimetric method allowed us to a...

Initially developed as one of the most successful methods for stimulating hydrocarbon production, hydraulic fracturing (HF) has gradually found its application in related fields, such as underground mining. At the same time, the importance of controlling the crack propagation path increases, since the design of in-mine hydraulic fracturing is a complex technological task due to the influence of mine workings and other inseam boreholes. When performing HF for the purpose of degassing a coal-bearing massif, there is...

In accordance with the latest trends, considerable emphasis is put on all mining companies in the Czech Republic not only on reducing the environmental impact of brown coal mining, but also on overall efficiency, the balance of which can be improved by increasing of the operational reliability of individual components of technological units and reducing operating costs. And it is the latter sphere, in that Vrsanska uhelna a.s. does considerable initiative. In cooperation with the firm RENOMAG s.r.o. and the Resear...

The work is devoted to the study of the effect of powdered WC monocarbide of different grain sizes, introduced into the composition of the binder of diamond grains of the composition 94 WC + 6Co + Cu in the manufacture of a diamond-bearing matrix of BS-NQ drill bits with a diameter of 75.6 mm, designed by ISM (Ukraine). The effectiveness of the mentioned crowns was evaluated according to the proposed indicator F= ( - mechanical drilling speed; h - the value of the deepening per single experience, - - linear wear o...

Psychosocial risks are defined by the International Labor Organization in terms of interactions between job content, work organization and management, and other environmental and organizational conditions, on one hand, and employee conditions, skills, and needs, on the other. Thus, psychosocial risks refer to those interactions that prove to have a dangerous influence on employees' health through their perceptions and experience. Long-term involvement in stressful work situations can lead to onset of burnout syndr...

DETEX Electronic Detonator made by Kirlioglu consists of an electronic circuit with communication and microprocessor and wire bridge resistance coated with explosive material. DETEX Electronic Detonator, which identity information, delay information, charge, discharge and all functions are controlled digitally, is a system consisting of all electronic circuit elements. The system consists of a communication circuit, a master control circuit with a microprocessor, a controlled charge, a discharge and an ignition ci...

It is advisable to conduct mining operations in the conditions of the ultimate state of the opened massif with an increase in the pit wall slope angles below the limit of effective use of combined motor-conveyor transport in the cleaning-up zone of deep and ultradeep open pit mines to the final depth. Such a design of the pit walls is achieved when mining benches from top to bottom within the boundaries of steep-slope layers with the use of in-bench loaders in the cleaning-up zone. The conditions for the occurrenc...

Conveyance of goods and travelling of persons through the tunnels of mines or subway is done on railways of narrow or normal gauge. In interventions in case of accidents, hydraulically operated installations with small dimensions are used for lifting and rerailing the derailed rolling stock. They include hydraulic jacks (double or single acting hydraulic cylinders), supplied with low flow rates at high pressures. Feeding of hydraulic cylinders for lifting and relocating the derailed rolling stock is usually done b...

Uranium mining companies of Kazakhstan during 15 years increased production of uranium more than 15 times using in-situ recovery of uranium (ISR). At the same time a significant part of uranium deposits contains gold, silver, palladium and rare metals like rhenium, germanium, scandium and et`s. The task was set for the complex extraction of associated metals from technological solutions of a uranium mine. Work was carried out to select and study samples of productive solutions and leaching solutions at one of the ...

Managing emergencies is a complex task, which involves precise coordination of many activities and people, as well as fast decision-making in environments in which critical, vital information can often be lacking. From a technical and technological point of view, in spite of all advances encountered in most industrial branches, accidents with human casualties and material damage can still occur. For this reason, the presence of special intervention and rescue teams within certain industrial/ economic units is esse...

The storage of explosives and pyrotechnic articles must be carried out in complete safety conditions and only in storage facilities (depots) arranged and authorized for this purpose. The legislation in force has strict provisions on the rules of explosive & pyrotechnics storage, handling and access in the storage facilities. Failure to comply with certain provisions of the law in the product safety data sheet prepared by the manufacturer may lead to the generation of hazardous situations which may result in very s...

Currently, one of the main problems in the extraction of useful minerals in term of environment is their transport in quarries. With the requirements to reduce the noise of the belt conveyor track, we were looking for a suitable solution to reduce it. So, we started thinking about attaching rollers made of a material other than steel. The final solution was to insert classic rollers in polyurethane beds called suspension cartridge - which are roller holders made of polyurethane and reinforced with a steel liner to...

The energy crisis triggered globally in the last quarter of 2021, forced Romania to go through a winter with liberalized electricity and gas prices, a period unprecedented in terms of consumer prices, accentuated by the result of closing energy targets that coalfired operations as a result of the imposition of EU conditions for the restructuring of the mining and energy sector. The year before, 2020, the COVID-19 pandemic, with restrictions imposed, produced a decrease in electricity demand, a decline in coal-fire...

The economic results of many dynamically developing European countries largely depend on the availability of mineral raw materials. For this reason, securing their supplies from import must be supported by a committed foreign policy as well as a sustainable raw materials policy in the field of their obtaining from domestic sources, both from mineral deposits, as well as secondary and waste sources. Raw material security must be based on the diversification of supply sources and minimizing supply risks. The results...

Underground mining remains one of the most dangerous occupations in the world, and coalmining is known for its high accident rates. In this paper we aim to present an overview of safety in the extractive industry and we will present statistics on known accidents. The repeated occurrence of explosions in underground mining raises questions about the measures taken to prevent their occurrence. Hazard identification and risk analysis are necessary to identify adverse events that may lead to a hazardous situation, to ...

In recent years, virtual reality developers have managed to create an artificial environment that can simulate reality so that the user has the impression of an almost real physical presence in the virtual world. By overlapping and synchronizing projected images with spatial sounds and even with forces that interact with the user, the user is detached from the real environment and an all-encompassing involvement in the virtual world occurs. Virtual reality is frequently present in aviation, medicine, military trai...

The article justifies the need for technological solutions in the use of polymer-composite materials in order to limit the impact of dynamic frictional forces in oil drilling. The relationship between macrostructural surfaces was investigated, in particular increasing the effectiveness of the axial load on the drill bit during drilling directional and horizontal wells. It is established that the polymer coating of drill string elements (BC) based on fluoroplastic brand F-4, with a small thickness of 2 ? 3 mm and t...

The evaluation of the seismic action generated by blasting, aims to establish the connection between the levels of ground vibration with the parameters of the blasting and the characteristics of the geological environment related to the quarry. In order to assess the seismic effects on site of the mining / civil / industrial objectives within the quarry, the criterion of the oscillation speed of the soil particles was chosen, because it was considered to be the only reproducible parameter for the whole frequency r...

Pipe conveyors belong to the most perspective systems for continuous transport technologies intended for the transport of bulk materials in various industries. In addition to the product and process quality, another important component of the quality evaluation system for pipe conveyors is the service quality. Service quality evaluation is based on the service quality of enclosed rubber conveyor belts which represent the most sensitive and the most expensive structural component of pipe conveyors. This article ana...

The Valea Jiului coal basin is the largest mining basin in Romania and includes from east to west the mining fields: Lonea, Lonea-Pilier, Petrila-Sud, Petrila, Livezeni, Salatruc, Dalja, Iscroni, Aninoasa, Vulcan, Paroseni, Lupeni , Lupeni-Sud, Barbateni, Uricani, Valea de Brazi and Campu lui Neag. The first opening works in the Lonea perimeter began with the excavation of the Rascoala gallery, in 1870, a gallery supported by brickwork. Also in the same period, the up-to-date exploitation of the outcrops from the ...

The main role of ventilation systems and especially air conditioning systems is to create indoor conditions and air quality inside the rooms that are independent of external atmospheric influences. The sizing of ventilation systems and especially of air conditioning systems is done, in most cases, by considering the climatic elements as a basis for calculation. The real limit to air quality insurance it consists in maintaining in the air certain concentrations of harmful substances which do not endanger human heal...

Despite all technical and technological advances, most industries are experiencing damage resulting in human casualties and property damage. Thus, the presence of special intervention and rescue teams at economic agent’s units is essential to limit / eliminate damage that generates toxic / explosive / flammable environments and rescue those caught in such events. The intervention activity in such special conditions can be carried out exclusively by trained and authorized personnel in this respect, personnel using ...

Quarry sites are famous for the different types of materials produced. Many aggregate elements, extracted by different methods in quarry activities, such as blasting operations, are widely used for different applications, such as construction, road paving and monuments. Generally, the process to obtain these materials is very complex. A stationary production facility does not require machinery to be moved or relocated, whereas the quarry process involves machinery such as wheel loaders, trucks and articulated dump...

Coal production in the Socialist Republic of Vietnam (SRV) is a strategic industry that provides resources to many sectors of the economy, including the energy industry, metallurgy, and construction. The distinctive characteristics of the Vietnamese coal industry are a high concentration of operations, the depletion of readily available reserves, and, as a result, an increase in underground mining activities, which already account for more than 60% of coal production. Coal mines belonging to Vinacomin, which is a ...

The structure of the tailings dump in the technological chain of a mining enterprise is functionally designed for storage of ore processing waste and clarification of technical water in the recycling water supply system of the mineral processing plant. In most cases, a tailings dump is an aggradation facility, the capacity of which is provided by the protective structures called tailings dams. The author analyses functional features of construction and operation of tailings in a technological chain of the mining e...

Mining is a very heavy industry. Every day miners take incredible risks to extract valuable ores and minerals from the earth's crust. In order to ensure the safe operation of the underground, adequate ventilation is required to ensure that the workplaces are permanently supplied with fresh air. By combining general ventilation with kilometers of secondary ventilation specific ventilation pipes, mining ventilation is a special area where errors can occur. Modeling and simulation of mining ventilation networks have ...

Modern industry is characterized by the intensive use of INDUSTRY 4.0 technologies and digitalization, which provide tools to increase efficiency, to reduce costs and achieve goals for the sustainable development of enterprises. This is also relevant for mining production as one of the areas of the general industry. INDUSTRY 4.0 technologies and digitalization increase the deposit development efficiency, optimize technological and production chains, improve mining safety, simplify internal and external logistics (...

Consideration of the issues of interaction of hydrogeological and geomechanical processes in mining development at water objects in difficult geological conditions is proposed. It is argued that the prediction of the interaction of these processes can be carried out on the basis of complementary deformation approach and the approach based on the theory of cracks. The issues in relation between the mining development and the negative impact on surface and underground waters as well on the safety and technology of p...

Regression analysis is one of the most used statistical methods, where it is necessary to determine the dependence of a certain quantitative (continuous) variable on one or more other quantitative (continuous) variables. The aim is to describe this dependence using calculations of given quantities. The paper aims to find the possibility of using this method in strategic management as a support tool. The research creates a tool in the MS Excel environment, which can find suitable dependencies according to defined p...

The vast territory of the Republic of Sakha (Yakutia), located in permafrost conditions and scattered by impassable roads, creates a serious problem in the energy supply of the population. In this regard, throughout the territory of the republic there are small open-pit mines with a production capacity of 40 to 200 thousand tons of coal per year to meet the needs of local consumers. The advantages of small open-pit mines are the low cost of coal mining, reduction of transport and transshipment costs, provision of ...

Unwanted effects of detonation of explosive materials (explosions) can occur due to deliberate actions (terrorist attack) or accidental. Modelling the effects of the explosion on the environment and the urban neighboring, occupies an important place in global and national research programs for the modernization of techniques for the safe use of explosives, in order to combat and operatively counter accidental explosions or those based on their use for terrorist purposes. The current trends are on the way to approx...

The dust cloud is the main form of existence of combustible dust in the production area and together with the existence of effective ignition sources are the main causes of dust explosions in production processes. Dust explosions are mainly characterized by the minimum ignition temperature, explosion limits, the minimum ignition energy, maximum explosion pressure and the rate of pressure rise. The explosive behavior which is represented by a mixture of air and flammable substance is influenced by many factors of w...

Taking into account the Regulation (EU) No 98/2013 of the European Parliament and of the Council of 15 January 2013 on the marketing and use of explosives precursors, which establishes harmonized rules concerning the making available, introduction, possession and use of substances or mixtures that could be misused for the illicit manufacture of explosives, with a view to limiting their availability to the general public, and ensuring the appropriate reporting of suspicious transactions throughout the supply chain,...

Dumping during open-pit mining is one of the important processes on which the area of disturbed lands and the environmental friendliness of the technology as a whole depend. In permafrost conditions, the issue of dumping requires a comprehensive study of the technology, dumping processes and taking into account the strength, thermophysical properties of frozen rocks. In most cases, when developing small coal deposits in the North-East of Russia, favorable mining and geological conditions of bedding are used for in...

Commonly the product’s life cycle ends up with waste. Conventionally the remains go to the landfill, earlier times – a dumpsite, the least manageable waste disposal method. To ensure that lost to society materials are treated with high priority, the European Union (EU) has implemented the Circular Economy Action Plan, continuing the monitoring of old dumpsites. The hierarchy of waste management points at preventing raw material use at first sight, but the following steps point at material reuse and recycling. The ...

The paper demonstrates relevance of diagnostics and monitoring of tailings as collectors of liquid mining wastes. The author has been an initiator and supervisor of the development of the methodological bases of combining multilevel observations to monitor hydraulic structures of tailings of mining enterprises. Monitoring observations are carried out at four levels: satellite, aerial, surface and subsurface (underground). The satellite level includes GPS geodesy, processing and analysis of optical and radar images...

The nature of their work places intervention and rescue personnel at the top of professions that face a considerable number of occupational health and safety risks, which are sometimes unavoidable. Often, this occupational category does not face a single safety risk, but a complex combination of risk factors, including unpredictability of situations in which they are required to work. The growing issue of protecting emergency workers against occupational health and safety risks has been highlighted as a priority b...

The use of indicator methods in oil and gas field geology allows us to obtain representative quantitative information about the direction and velocity of fluid movement in the studied formations, to assess the main filtration parameters and the presence of inter-reservoir flows, as well as reliable information about the technical condition of wells. The use of indicators (tracers) is based on the injection of water (or an aqueous solution of the reagent) labeled with a stable or radioactive indicator and subsequen...

In Oituz and Targu Ocna, the attestation of salt extraction was established during the Geto-Dacian period. The oldest written testimony dates from 1380. The mining works that serve the Trotus mine within the Tg. Ocna Salt Mine, are located in the Fetele Targului salt massif located near the town of Tg. Ocna, on the left side of the Trotus river. Currently, the Trotu? Salt Mine has 14 horizons: 2 at the Pilot mine and 12 at the Trotu? mine. The specialized 3D CANVENT program was used to establish the optimal distri...

Usually, only a part of the work capacity is spent in the professional activity, being materialized as products and services made/accomplished within the work process. However, there are also instances, in extreme cases, when total work capacity needs to be engaged, thus an important body reserve being used. Work capacity is represented by the totality of an individual’s (physical, mental, intellectual) possibilities to perform a useful activity at an optimal level of intensity and efficiency. One of the most impo...

In the paper the authors present the study results of rock massif fracture based on the case study of a rockburst hazardous Khibiny deposit. The authors have revealed peculiarities in seismic process at different mining stages over a five-year period. The principal aim was to study the particularities of seismicity occurrence when the deposit is mined by approaching fronts, namely, in the periods between bulk blasts in the docking sections between them. The authors have proposed an approach to reveal the features ...

The purpose of the research was to develop an algorithm for a comprehensive assessment of the sustainable development of a mining enterprise based on an integral indicator from the standpoint of environmental performance and test it on the example of the largest Russian coal and energy company SUEK. In modern conditions the Russian energy sector is in a state of transformation, which is associated with the strengthening of globalization processes, tougher competitiveness and management of production systems. Moreo...

In the process of hydraulic fracturing (HF), pressurized fluid is supplied to an isolated interval of the well. This causes the formation of an artificial crack, the growth direction of which greatly affects the method efficiency. It is especially important to take this into account when designing in-mine hydraulic fracturing for the solid minerals development. In this case HF is carried out close to underground workings and other inseam boreholes and these factors can influence the stress-strain state of stimulat...

Unlike friable rocks, salt behaves pseudoplastic when blasted, which leads to other premises of the blasting technique compared to those applied for stratified sedimentary or eruptive rocks. Here can also add the salt inhibitory character on the thermodynamic parameters of the explosions, with effects on their efficiencies as well as some particularities of the execution of the blasting works due to the presence of methane gas in the salt mines. The article presents the results of the research carried out in fired...

One of the main tasks of open pit mining, besides maintaining the planned productivity, is to ensure the safety of production and personnel, and to keep the stability of the elements of open pit geotechnology. The open-pit mining operations form a large open-pit excavation for dozens of years, which results in a gradual change in the properties and state of the adjacent rock mass and in a decrease in its strength and elastic characteristics. This circumstance makes periodic monitoring of the geomechanical state of...

Belt conveyors constitute an important part of the machinery for the underground and surface mining of materials. In the course of time, conveyor belts proved to be the most efficient way of transporting material, which is still valid not only in the mining industry. For the transport of rocks to a mine disposal site, a combination of multiple belt conveyors is necessary. Places of transfer belong to the most stressed parts and there are frequent breakdowns. They operate in difficult conditions and are subject to ...

Objective of the research is to develop annular-type drilling tools, which application increases mechanical velocity of drilling and overall productivity of drilling operations. Methodology is represented by the following: analysis and generalization of the scientific and technical achievements in mining industry; mathematical and physical modeling; and numerical methods of solution. Findings – a drill bit with following features has been developed: first, during the initial well sinking, the bit operates with one...

In the paperwork are presented aspects regarding uncertainty involved in the process of spark ignition assessment for intrinsically safe equipment. In the first part of the paper was presented the explosion risk. In the field of power generation and also, in a lot of other fields of industrial activities, the occurrence of flammable substances is a common fact. As a consequence, an explosion risk can occur. On the other hand, the installations placed in areas endangered by presence of flammable substances should b...