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The problems of geodynamic safety assurance in mining are common for many countries with developed mining industries. Considerable results have been achieved in Russia in solving rockburst problem, yet in the last decades this problem is transforming into man-triggered seismicity problem. Induced earthquakes in areas where mines had been flooded, seismic activity in previously safe regions, re-activation of tectonic faults, violent man-triggered earthquakes in open pit operations have been registered. As a matter ...

Substances that have chemical energy are known under the generic name of explosives. The chemical energy resulting from the decomposition of explosive substances has constituted and will continue to be one of the main forms of energy used in many sectors of the economy as well as in the military field. The technical experience accumulated so far has demonstrated that it is very difficult for a simply characterization of the explosion. Thus, in order to achieve this it is necessary to know the thermo-chemical chara...

One of the complicating factors in oil production is the deposition paraffin, as a result of which the production well rate is decreasing and the Electric submersible pump failure occurs. The main factors influencing the intensity of paraffin formation are: downhole temperature, gas evolution, hydrocarbon composition in each phase of the mixture, high viscosity of oil, change in the velocity of the gas-liquid mixture. To solve problems, the thermal method is used, which consists in artificial increase of the well ...

The underground mining of a deposit leads inevitably to the deformation of the surface as well as to the destruction of the buildings located in the area of influence of the extraction. Therefore, the rocks surrounding the excavation, created by the extraction process, go from the initial equilibrium state of tensions (triaxial) to a biaxial or even uniaxial stress state. This secondary state of tension leads to the occurrence of rock breaking phenomena in the areas where their resistance are exceeded, respectivel...

Facilities and technical systems used in coal mines have limited durability. This is the result of very difficult conditions in which they are used. In particular it applies to environmental conditions and not entirely predictable load states of these facilities. Mining machines and devices are also exposed to various types of hazards, which in many cases significantly reduce their durability. For this reason, it is very important to properly use them and supervise and monitor their work. In this respect, huge res...

In the Czech Republic, mining is regulated by a number of laws and decrees. The basis of this article is the approximation of legal provisions and their quantitative expression, the legal provisions applied in the area of economical exploitation of mineral resources in our territory. The provisions of the Upper Law are based on four fundamental principles and, on the basis of these principles, the provisions regarding the economical exploitation of mineral resources can be assigned to the individual principles. Am...

The paper presents information about the mineral resource base of the Republic of Sakha (Yakutia)-one of the richest regions of Russia in minerals and severe climatic conditions of their development, the presence of almost universal permafrost causes a particular vulnerability of the environment in mining. In this regard, the methods and results of studies of the geoecological state of the landscape in the development of Geosciences, including space surveys of mining operations, the regime of their restoration by ...

The pressure transducer installed in the hydraulic system play an important role for the correct work of the powered roof support. Currently, in the free market economy there are many manufacturers offering a wide range of such products, however, it is often difficult to find a solution that would meet specific requirements, for example when selecting a pressure transducer for a powered roof support. It is difficult to find an ideal transducer that would meet all the requirements for the correct operation of the s...

Psychological research makes progress in associating personality traits with specific actions and behaviours, seeking individual differences in brain anatomy and physiology, in body functions and processes of self-regulation, sensation and perception, in information processing and thinking patterns, in behaviour and emotional regulation, in interpersonal interactions and many other psychological indicators. Depending on the characteristics of the work environment, various psychological indicators are involved in r...

Restructuring of mining activity in Romania resulted in active implementation of reconstruction programs, upgrading and modernization of the mines in the Jiu Valley. These programs were aimed mainly at increasing labor productivity safely. Considering, along with requirements for ensuring a safe and healthy working environment, also the issues related to the drained methane valorization and to environmental protection restrictions it was imposed to rethink the so-called "global methane treatment" at the level of m...

Work safety in hard coal mines is implemented based on Geological and Mining Law. It imposes an obligation on the entrepreneur to identify hazards related to activities of the mine and to undertake actions aimed at preventing and removing these threats and hazards. The owner is required to assess the risk and propose solutions necessary to minimize it. These activities must cover all activities performed during the production process and the operation of all types of equipment, including mining machines. The most ...

The use and maintenance of underground spaces in bedrock, e.g. those formed upon the completion of mining operations, often gives rise to discussion of other uses of remaining tunneling systems. Filling tunnels with rock blocks, concrete and groundwater is not always an optimum decision because this environmentally controlled work requires funding. Another option is to establish underground laboratories (UL?s) at these locations and to use underground spaces for non-quarrying purposes. However, the transition of s...

In this study, the environmental impacts of blasting activities carried out for excavation of a building foundation close to a nearby building were investigated. The study was performed due to the complaints and request of the residents. Before blasting activities (shots), the residents, the investor and the blaster were informed about the environmental effects of blasting, regulations and the measures if an adverse effect occurs. In this scope, 7 shots were accompanied and blast-induced parameters were monitored....

The article presents research on the capacity of Polish mining enterprises to introduce organizational changes. The main difficulties, which are problems arising in the introduction of changes in enterprises are primarily generated by the human factor. Moreover, the efficiency of the organization during the process of change depends largely on the productivity of employees. Therefore, our change management research focuses to the greatest extent on the situation of people in the organization. The authors carried o...

The purpose of this paper is to determine the rate of methane (explosive gas) and of carbon dioxide (asphyxiating gas) in the mine workings of Dej salt mine. In Romania there are six salt mines which exploit the salt through underground mine workings: Dej salt mine, Tg. Ocna salt mine, Slanic Prahova salt mine, Ocnele Mari salt mine, Cacica salt mine, and Praid salt mine. The purpose of the present paper work is to establish the methane release (explosive gas) and the carbon dioxide release regime in mine workings...

Applying iterative techniques to relatively simple ventilation networks, involves a considerable volume of mathematical calculations. For systems encountered in practice, the iterative methods become impracticable if the repeated calculations are to be performed manually. Computers can provide help in calculating mesh correction factors, respectively in calculating the branch flow rates. However, the number of iterations to be applied, along with organizational arrangements for mesh selection and network upgrading...

The management system of technological processes at open pits is a system for planning and managing mining and transport operations and includes such types of planning as perspective, current and operational. The most difficult to implement and requiring the highest degree of accuracy, and also the most responsible is the shift operational planning. This stage is also characterized by the fact that it requires maximum interconnection and co-ordination of mining planning and management systems. Within the scope of ...

Belt conveying belongs to high-performance, economically and energy efficient continuous system. Optimization of this conveying systems makes possible reducing the total operating costs up to 30%. For this reason is necessary to choice of the suitable structural elements. Conveyor belt is the most important element of this system and quality of its strength properties is a needful prerequisite for a smooth operation of belt conveyors. Insufficient quality of strength properties has a negative effect on the reliabi...

It is a certainty that a rock massif is a very complex environment, known only partially; in the laboratory we cannot produce all the details encountered in situ; therefore, most of the properties determined experimentally not fully express their real value that they have in rock massif. As theoretical basis we might consider theory of similitude initiated by Newton, in the sense of similarity that we can establish to the boundary between theory and experiment. Based on this and considering the applicable theorems...

In a practical context and with a tendency to generalize the dependence between monoaxial and triaxial compressive strength of rocks and qualitative characteristics and also properties of connection between the elements that form the skeleton of studied rocks were analyzed. This qualitative connection was highlighted by means of void index and apparent specific weight. The obtained correlation can be generalized to any type of rock, if it takes into account the amount of adsorbed and absorbed water, the direction ...

This paper pursue ways of effective utilization of surveyor mining documentation fundaments in practical application of mining design and additional following professions. Special emphasis is put on utilization of historical documentation fundaments, nowadays stored in archives. Principal part of paper is dedicated to reverse construction of Pokrok fill solid foundation from analog and digital documentation and 3D interpretation of the results. 3D model of material distribution in the dump body is final result of ...

In this article, the stages of creating three-dimensional geomechanical models in the development of deposits by open method are considered in detail, based on the results of calculating the safety factor of the open pit sides. The geomechanical model consists of four main components - geological, structural, hydrogeological models and rock mass model. The models are based on the geological, hydrogeological, geotechnical data of the field. Such geomechanical models allow to optimize the work of the whole enterpris...

The most important products of the seismological network are complete and reliable earthquake catalogs. Detecting earthquakes over an extended scale, from smallest magnitudes to large events is a critical issue in many studies, such as earthquake statistics, source seismology and seismic hazard. During the last years, the seismic network of Romanian has developed by increasing the number of stations and station coverage. Despite the significant improvement, the coverage is still not uniform all over the Romanian t...

The establishment of the characteristics to mechanical cutting of the rocks through chipping, just as it happens in practice for the bucket-wheel excavator having teeth, represents an elemental problem and underlies the concrete knowledge of rocks dislocation. Interdependency laws among the geometric parameters and technological ones of the chipping teeth, the parameters of the dislocated chippings and the parameters of the cutting regimes which can be established taking into account qualitative and quantitative a...

The belt conveyance plays an important role in mining, bulk material transportation, raw materials processing, and in many other areas (e.g., metallurgy, wood-cutting, and energetics) where large quantities are transported over the distances ranging from a few meters to several kilometres. A conveyor belt, as the basic element of the mining transport, is of particular economic significance. Increasing the belt service life, which can be achieved by reducing the wear of conveyor belts, has a high priority. The top ...

Adaptability of training complexes, i.e. the possibility of their optimization for the psychophysical characteristics of the student, is a promising direction in the design of such systems. Design, optimization and implementation of adaptive training complexes (ATC) is impossible without the development of mathematical and algorithmic support, allowing to represent the entire sequence of stages of creation of the training complex. Due to the modular principle of building a system and decomposition of the original ...

The paper informs about the process of development and testing of dynamic cone penetration test semi-automatic data recorder. Dynamic probing is widely used in-situ testing procedure. The test principle is to drive a rod with a cone tip on its end into a soil by a ram. During the test an operator records the number of blow count and value of torque moment evaluating the soil lateral friction with rods. Keeping the handwritten record during test is a concentration demanding process providing large room for human er...

In the aim of preventing and controlling major accident hazards involving dangerous substances, many risk assessment methodologies have been developed worldwide. Until now, in Romania no formalized methodology has been proposed to competent authorities to determine the risk level of an industrial establishment. Based on the critical analysis of the risk assessment methods, there have been identified the key elements of the methodological basis of risk assessment for establishments concerned by the requirements of ...

The hazard of tecnogenous earthquakes caused by mining of mineral deposits is increased if they occur at economically developed regions with ecologically dangerous objects. A deep coal mine of the Sinvay deposite in China is an example when seismicity due to mining was an important factor influencing both the mining conditions and ecological environment. At a more than 1000m mining depth the power of rock bursts rose to 107 J and they manifested themselves as minor earthquakes on the earth surface. The increasing ...

An electrohydraulic control system as a part of powered roof support is required to be equipped with a safety valve. The aim of the valve is to protect the roof support against overloads that may damage hydraulic legs, and subsequently lead to loss of stability of the whole support unit. In order to select optimal operating parameters of the safety valve it is necessary to carry out tests in conditions similar to those in the mine. The tests should reflect the actual load condition of the support as much as possib...

The choice of support design for mine excavations driven beyond the influence zone of stoping in the conditions of permafrost is governed by the service life of the excavations, geomechanical behavior of surrounding rock mass and by working temperature range of ventilation. The research findings on influence exerted by temperature on stress state of rock mass around a single tunnel are presented. Based on solution of quasistatic thermo-elastic problems, the mechanisms of change in the stresses and displacements at...

The flow properties of porous media play an important role in the study of hydrodynamic processes in oil and gas reservoirs. Such characteristics as absolute permeability coefficients, capillary pressure curves, relative phase permeability cannot be estimated from well logs and seismic survey. Their measurements in laboratory are time-consuming and cost expensive. An alternative approach for estimation flow properties is "Computational Rock Physics" using computational experiments on digital models of porous media...

The problem of industrial ventilation has emerged as a result of the serious pollution problems that arise both in the industrial and industrial environments. Before addressing an industrial ventilation study, the question should be raised whether there is no simpler means of reducing or eliminating the causes of pollution or of reducing pollution by modifying the production process or the design and construction of the actual ventilation system. Verification of ventilation facilities has a strong preventive role ...

The paper deals with the purchase and sale of electricity in companies like huge opencast brown coal mine. Regulation of electric energy usage is still an underrated component of automatization equipment in some companies. If good energy regulation methods are being used, not only financial saving will be achieved, but also energy supply and distribution system quality will get better. This article describes one of the most important systems for saving money and effectively managing the use of electricity in the m...

The publication concerns the issue of losses and gains related to the rock mining activity in the whole business life cycle of a mining undertaking in relation to: mining entrepreneur, communes, local communities and the environment. The analysis of the issues was conducted for three specific stages of a mining undertaking: identification of geological resources and technical and economic analyses of an undertaking, preparatory works, deposit opening and mining as well as winding up of the mine. The conducted anal...

Rocks can be structurally represented as layered bodies, whereby the layers can be located at different orientation angles with respect to the original ground. Such angles are usually called the bedding angles. To avoid mistakes in the calculations of the stress-strain state of rock massifs, it is very important to take into account the dependencies of mechanical properties of layered rocks on the bedding angle. Also, rocks are at a certain depth under hydrostatic compression conditions. For an adequate simulation...

Calculation of the mining support in tunnels and/or underground facilities can be based on application of contemporary numerical methods, but sometimes it can be performed with the classical methods too. These methods can be found to be used in order to choose variants and ways of supporting, but also in the moments that unpredictably appears during the construction of facility. Before installing a permanent mining support, these methods can help the projector at the selection of type of support and ways of tempor...

The results of the study of high-Mg rocks from the Aganozero chromite deposit, located in the Republic of Karelia, are reported. It is a complex type of deposits. Other promising useful minerals, in addition to chromite ore mining, are Mg-rich ultramafics such as olivinite, dunite, serpentinite and pyroxenite. High-Mg dunite units are thick, and their MgO concentration varies 36.97 from 46.77%. Aganozero dunite is a good raw material for the production of refractory materials, e.g. refractory bricks, steel furnace...

The former village Rosiuta, now neighborhood of Motru city, located in Motru mining basin, is surrounded by sterile waste dumps and lignite storage platforms. These are a constant source of particulate matter which is carried by the wind over the inhabited area and affects the quality of breathing air. In order to evaluate the powders dispersion from these sources, it was made chemical and granulometric analysis of the particulate matter on several material samples collected from the area. Based on various meteoro...

Industrial ventilation and air conditioning systems aim at ensuring the air purity and microclimate conditions of the human activity and the nature of the technological process. These ventilation systems help in maintaining work capacity, removing occupational illnesses, increasing the labour productivity and the quality of work-related products. The structure of ventilation systems in spaces and industrial premises requires a thorough knowledge of the technological processes that take place, of the equipment and ...

The use of the borehole camera when observing the blasting results in clay soils provides accurate data on the effects. For this purpose, GNSS, Heavy Duty GeoVision borehole camera, and laser (EDS-C) integration were used. The spherical cavity formed after the detonation of the explosive charge in the bottom of the borehole was measured with the aid of a borehole camera and a laser system. The measurement data obtained was used to determine the coordinates of the boreholes at a certain depth of recording based on ...

The accelerated ageing affects the quality of an important element of the belt conveyance ? a conveyor belt. This paper analyses the resistance of the belt cover layers to the deterioration caused particularly by the accelerated ageing. The investigation was carried out using the fabric conveyor belts of the P 2000/4 type (4-layer textile belts with a polyamide carcass, the strength of 2,000 N/mm) at different ageing periods. The effect of ageing on the rubber cover layers was identified on the basis of the observ...

The investigated lead - zinc ore panel is located in the Blaznei Valley ore deposit, Romania. Applying traditional methods for determining the average thickness proves useful in its exploration, although there are only four points of thickness measurement, located in each corner of the exploration panel. Later, in the second stage of the exploitation process (preparation), when the exploration panel becomes an operating (exploitation) panel by contour mining of four workings, two groves on direction and two runs, ...

The quantification of the influence exerted on the targets from an establishments concerned by the SEVESO II Directive requirements can be performed through the potential danger resulting by the aggregation of the gravity index and the propagation flow index. Starting from the environment?s specific characteristics, the major accident?s propagation kinetics and the distance between the target and the danger source, the paper has as goal to depict a propagation flow determination method. In this index determination...

At present, we have a number of legal provisions in the Czech Republic that give miners the responsibility to make economic use of mineral deposits. The main one is Upper low No. 44/1988 Sb. on the Protection and Use of Mineral Resources, referred to as the Upper Law, there are also laws, decrees and government orders that are closely related to or follow the Upper Act or impose further expansion obligations for the economical exploitation of mineral resources in our country. Despite a number of existing legal pro...

Antropogenic seismicity is one of the most important geomechanical hazard encountered in Polish deep copper mines. Obviously, it may have a negative impact on the people?s safety and the production process. In such circumstances, a number of both active and passive prevention measures have been implemented in the mines, at least partially. One of the most effective, applied for many years, active means used for seismic hazard reduction, is multi-faces blasting works which by assumption should result in release of ...

The paper presents the results of theoretical and practical research on developing the infrastructure for assessment of overall risk (explosion / occupational terrorist attack) associated with unwanted events such as major accidents that can occur at explosive storehouses for civilian use. The scientific research outlined in this article was carried out within the NUCLEU Project PN 16 43 02 15 - ?Research on increasing safety levels at technical facilities for storage of explosives for civil use?. The key element ...

The target of this article is the providing of the brief information about preventing the dust spreading problems solving during operations of machinery equipment in brown coal open pit mines and in coal dumps. The main part of this paper briefly describes operation tests of the new rotary mist unit realized during last years. The increased concentration of the dust in the air causes important health hazard. The dust is very bother factor. The occurrence of the dust in operation area is the source of danger fire r...

The particularities of the hydraulic system of the roof supports are determined by the repetitive structure specific to the supporting component, by the supply network, by the operating liquid and by the length of the coalface, as well as by the operation principle of the pumping station supplying the execution elements with the average flow given by the load and the resistance of the hydraulic networks. The paper highlights all these particularities bringing forward a series of practical details for calculation o...

One of the main problems industries in general are facing is the prediction of errors or failures of the most sensitive or critical assets of their equipment. For this reason, techniques based on predictive maintenance are emerging, searching for the early detection of possible cracks, imperfections or defects that are likely to cause an accident or the partial or complete shutdown of a plant. The main objective is to anticipate breakages in order to improve the planning and scheduling of control and maintenance o...