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Date submitted2024-06-17
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Date accepted2024-07-17
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Date published2024-10-03
Justification on the safe exploitation of closed coal warehouse by gas factor
The annual increase of coal production and its demand lead to the necessity in temporary storage places (warehouses) organization to accommodate raw coal materials before the shipment. It is noted that at the open method of coal storing the dust emission from loading/unloading operations and from the pile surface effects negatively the health of the warehouse workers and adjacent territories. An alternative solution is closed-type warehouses . One of the main hazards of such coal storage can be the release of residual methane from coal segregates into the air after degassing processes during mining and extraction to the surface, as well as transportation to the place of temporary storage. The study carries the analysis of methane content change in coal during the processes of extraction, transportation and storage. Physical and chemical bases of mass transfer during the interaction between gas-saturated coal mass and air are studied. It is determined that the intensity of methane emission depends on: the coal seam natural gas content, parameters of mass transfer between coal, and air and the ambient temperature. The dynamics of coal mass gas exchange with atmospheric air is evaluated by approximate approach, which is based on two interrelated iterations. The first one considers the formation of methane concentration fields in the air space of the bulk volume and the second accounts the methane emission from the pile surface to the outside air. It is determined that safety of closed coal warehouses exploitation by gas factor can be ensured by means of artificial ventilation providing volumetric methane concentration in the air less than 1 %. The flow rate sufficient to achieve this methane concentration was obtained as a result of computer modeling of methane concentration fields formation in the air medium at theoretically calculated methane emission from the pile surface.
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Date submitted2023-03-14
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Date accepted2023-06-20
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Date published2023-07-19
The wireless charging system for mining electric locomotives
The electric vehicles development has a high potential for energy saving: an energy-saving traffic control can reduce energy resource consumption, and integration with the power grid provides the ability of daily load pattern adjustment. These features are also relevant for underground mining. The critical element of vehicle-to-grid integration is the charging infrastructure, where wireless charging is promising to develop. The implementation of such systems in underground mining is associated with energy efficiency issues and explosion safety. The article discusses the development and research of a wireless charging system for mining electric locomotive A-5.5-600-U5. The analytic hierarchy process is used for justification of the circuitry and design solution by a comparison of different technical solutions based on energy efficiency and safety criteria. A complex computer model of the wireless charging system has been developed that gives the transients in the electrical circuit of a wireless charging system and the high-frequency field density distribution near the transmitting and receiving coils in a 3D setting. An approach to ignition risk evaluation based on the analysis of high-frequency field density in the charging area between the coils of the wireless charging system is proposed. The approach using a complex computer model is applied to the developed system. The study showed that the wireless charging system for mining electric locomotives operating in the gaseous-and-dusty mine is technically feasible and there are designs in which it is explosion safe.
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Date submitted2022-10-13
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Date accepted2022-12-13
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Date published2023-07-19
A complex model of a drilling rig rotor with adjustable electric drive
A modified mathematical model of an asynchronous electric drive of the rotor – a drill string – a bit – a rock is considered and implemented, which develops and generalizes the results of previously performed studies. The model includes the following subsystems: a model of an asynchronous drive with vector control; a model of formation of the resistance moment at the bottom of the bit, taking into account the peculiarities of the interaction between the bit and the rock; a model of a multi-mass mechanical part that takes into account the deformation of the drill string; subsystem for the drilling rig energy-technological parameters formation. The integrated model makes it possible to calculate and evaluate the selected drilling modes, taking into account their electro-mechanical, energy and technological efficiency and the dynamics of drilling processes. The performed computer simulation of drilling modes confirmed the possibility of a stick-slip effect accompanied by high-frequency vibrations during bit stops, which may change the direction of rotation of the bit, its accelerated wear and unscrewing of the drilling tool. Long bit stops lead to a significant decrease in the average bit rotation speed, which can explain the decrease in the ROP and increase in energy consumption when drilling in the zone of unstable bit rotation. The model can be used as a base for further improvement of rotary drilling control systems.
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Date submitted2022-08-20
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Date accepted2022-11-17
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Date published2022-12-29
Comparison of the approaches to assessing the compressibility of the pore space
- Authors:
- Vitaly S. Zhukov
- Yuri O. Kuzmin
Integral and differential approaches to determining the volumetric compression of rocks caused by changes in the stress state are considered. Changes in the volume of the pore space of rocks are analyzed with an increase in its all-round compression. Estimation of changes in the compressibility coefficients of reservoirs due to the development of fields is an urgent problem, since the spread in the values of compressibility factors reduces the adequacy of estimates of changes in the physical properties and subsidence of the earth's surface of developed fields and underground gas storages. This parameter is key in assessing the geodynamic consequences of the long-term development of hydrocarbon deposits and the operation of underground gas storage facilities. Approaches to the assessment differ in the use of cumulative (integral) or local (differential) changes in porosity with a change in effective pressure. It is shown that the coefficient of volumetric compressibility of pores calculated by the integral approach significantly exceeds its value calculated by the differential approach, which is due to the accumulative nature of pore compression with an increase in effective pressure. It is shown that the differential approach more accurately determines the value of the pore compressibility coefficient, since it takes into account in more detail the features of the change in effective pressure.
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Date submitted2021-12-21
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Date accepted2022-06-20
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Date published2022-11-10
Scientific justification of the perforation methods for Famennian deposits in the southeast of the Perm Region based on geomechanical modelling
The article presents the results of analysing geological structure of the Famennian deposits (Devonian) in the Perm Region. Numerical modelling of the distribution of inhomogeneous stress field near the well was performed for the two considered types of perforation. With regard for the geometry of the forming perforation channels, numerical finite element models of near-wellbore zones were created considering slotted and cumulative perforation. It is ascertained that in the course of slotted perforation, conditions are created for a significant restoration of effective stresses and, as a result, restoration of reservoir rock permeability. Stress recovery area lies near the well within a radius equal to the length of the slots, and depends on the drawdown, with its increase, the area decreases. From the assessment of failure areas, it was found that in case of slotted perforation, the reservoir in near-wellbore zone remains stable, and failure zones can appear only at drawdowns of 10 MPa and more. The opposite situation was recorded for cumulative perforation; failure zones near the holes appear even at a drawdown of 2 MPa. In general, the analysis of results of numerical simulation of the stress state for two simulated types of perforation suggests that slotted perforation is more efficient than cumulative perforation. At the same time, the final conclusion could be drawn after determining the patterns of changes in permeability of the considered rocks under the influence of changing effective stresses and performing calculations of well flow rates after making the considered types of perforation channels.
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Date submitted2021-04-06
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Date accepted2022-04-27
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Date published2022-07-13
Experimental study on the effect of rock pressure on sandstone permeability
The results of laboratory studies to determine the effect of effective stress on the permeability of sandstone are presented. During the test, the samples were subjected to a stepwise increase or decrease of the effective stress (at a constant pore pressure) in a specified step. The values of rock permeability at different values of effective stress were determined, and the influence of the grain size of the reservoir rock matrix on the character of the change in the sandstone permeability coefficient was also established. During the test, a decrease in permeability was observed with an increase in effective stress. It was found that as a result of gradual loading/unloading of the sandstone sample, the original permeability values were not restored, which indicates the beginning of the formation of residual strains in the rock. This effect should be taken into account when modeling field development because in the process of reserves extraction the effective stress acting on the reservoir rock skeleton changes, which results in a significant chang in rock permeability. The results of laboratory studies showed that the deviation of permeability in medium-grained sandstones relative to the initial value was greater than in medium- and fine-grained sandstones. The pressure sensitivity coefficient and constant of material, which are used in empirical relationships between permeability and effective stress, were numerically estimated. At the same time, the constant of material showed no such convergence, which indicates that the values of this parameter are individual for each rock.
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Date submitted2021-05-19
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Date accepted2022-04-07
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Date published2022-04-29
On the possibility of reducing man-made burden on benthic biotic communities when mining solid minerals using technical means of various designs
The paper analyses features of the species composition and diversity of biotic communities living within the ferromanganese nodule fields (the Clarion-Clipperton field), cobalt-manganese crusts (the Magellan Seamounts) and deep-sea polymetallic sulphides (the Ashadze-1, Ashadze-2, Logatchev and Krasnov fields) in the Russian exploration areas of the Pacific and Atlantic Oceans. Prospects of mining solid minerals of the world’s oceans with the least possible damage to the marine ecosystems are considered that cover formation of the sediment plumes and roiling of significant volumes of water as a result of collecting the minerals as well as conservation of the hydrothermal fauna and microbiota, including in the impact zone of high temperature hydrothermal vents. Different concepts and layout options for deep-water mining complexes (the Indian and Japanese concepts as well as those of the Nautilus Minerals and Saint Petersburg Mining University) are examined with respect to their operational efficiency. The main types of mechanisms that are part of the complexes are identified and assessed based on the defined priorities that include the ecological aspect, i.e. the impact on the seabed environment; manufacturing and operating costs; and specific energy consumption, i.e. the technical and economic indicators. The presented morphological analysis gave grounds to justify the layout of a deep-sea minerals collecting unit, i.e. a device with suction chambers and a grip arm walking gear, selected based on the environmental key priority. Pilot experimental studies of physical and mechanical properties of cobalt-manganese crust samples were performed through application of bilateral axial force using spherical balls (indenters) and producing a rock strength passport to assess further results of the experimental studies. Experimental destructive tests of the cobalt-manganese crust by impact and cutting were carried out to determine the impact load and axial cutting force required for implementation of the collecting system that uses a clamshell-type effector with a built-in impactor.
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Date submitted2021-04-30
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Date accepted2021-11-30
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Date published2021-12-27
Methodology for testing pipeline steels for resistance to grooving corrosion
- Authors:
- Viktor I. Bolobov
- Grigoriy G. Popov
The methodology for testing pipeline steels is suggested on the assumption that for the destruction of pipes in field oil pipelines by the mechanism of grooving corrosion the simultaneous fulfillment of such conditions as the occurrence of scratches on the lower generatrix of the pipe, eventually growing into a channel in the form of a groove, emulsion enrichment with oxygen, presence of pipe wall metal in a stressed state, presence of chlorine-ion in the oil-water emulsion is required. Tests are suggested to be carried out in 3 % aqueous solution of NaCl with continuous aeration by air on bent plates 150×15×3 mm, made of the analyzed steel, the middle part of which is under the action of residual stresses σ res , close to the level of maximum equivalent stresses σ eqv in the wall of the oil pipeline, with the presence of a cut on this part on the inner side of the plate as an initiator of additional mechanical stresses. Using the value of the modulus of normal elasticity of the analyzed steel, the degree of residual strain of the elastic-plastic body from this material, corresponding to the value σ res ≈ σ eqv is calculated, based on which the plates are bent to the required deflection angle, after which the cut is applied to them. After keeping the plates in the corrosive medium for each of them the increase in depth of the cut as a result of corrosion of the walls by the corrosive medium is analyzed, from which the rate of steel K by the mechanism of grooving corrosion is calculated taking into account the duration of tests. Corrosion rate values for two pipe steel grades determined by the suggested procedure are given. The comparison of K values obtained leads to the conclusion about the higher resistance to grooving corrosion of 09G2S steel.
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Date submitted2021-03-17
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Date accepted2021-04-12
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Date published2021-06-24
Application of the resonant energy separation effect at natural gas reduction points in order to improve the energy efficiency of the gas distribution system
- Authors:
- Andrei M. Schipachev
- Alena S. Dmitrieva
Maintaining the gas temperature and the formation of gas hydrates is one of the main problems in the operation of gas pipelines. Development and implementation of new effective methods for heating the gas during gas reduction will reduce the cost of gas transportation, solve the problem of resource and energy saving in the fuel industry. Study is aimed at increasing the energy efficiency of the natural gas reduction process by using a resonant gas heater to maintain the set temperature at the outlet of the gas distribution station (GDS) and prevent possible hydrate formation and icing of the station equipment. Paper considers the implementation of fireless heating of natural gas and fuel gas savings of heaters due to the introduction of a thermoacoustic reducer, operating on the basis of the Hartmann – Sprenger resonance effect, into the scheme of the reduction unit. By analyzing the existing methods of energy separation and numerical modeling, the effectiveness of the resonant-type energy separation device is substantiated. Modification of the reduction unit by introducing energy separating devices into it will allow general or partial heating of natural gas by its own pressure energy. Developed technology will allow partial (in the future, complete) replacement of heat energy generation at a gas distribution station by burning natural gas.
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Date submitted2021-03-12
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Date accepted2021-04-12
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Date published2021-06-24
Increasing the efficiency of phosphate ore processing using flotation method
The paper presents flotation of two phosphate ore samples of different origin. Statistical analysis was used to study the effect of operating parameters on flotation efficiency. The paper proposes to increase the efficiency of flotation processing of magmatic phosphate ore with a low grade of the valuable component (P 2 O 5 = 10.88 %), containing nepheline and feldspars, by means of direct anionic flotation. Authors present an optimization of anionic flotation using tall oil fatty acids mixed with anionic phospholane as an anionic collector. The effect of adding soda ash to compensate for the influence of calcium cations on technological parameters of P 2 O 5 flotation was examined. The results of studying the flotation of nepheline ore (flotation tailings of magmatic phosphate ore) showed that replacement of phospholane with oxyethylated isotridecanol allowed to obtain a high-quality concentrate. It was estimated that with the addition of Na 2 CO 3 in the amount of 2,000 g/t, a concentrate was obtained with the grade and recovery of phosphorus pentoxide equal to 39.15 and 94.19 %, respectively. The paper proposes to increase the efficiency of flotation processing of sedimentary phosphate ore with a low grade of the valuable component (P 2 O 5 = 22.5 %), containing gypsum and quartz, by means of desliming followed by anionic or cationic reverse flotation. Tall oil fatty acid with anionic phospholane was used as a collector in anionic reverse flotation, and amine was used in cationic reverse flotation. Sodium tripolyphosphate was used as a P 2 O 5 depressant. It was found to be an effective depressant in both anionic and cationic flotation. When analyzing the statistical plan, it was estimated that the maximum grade of the valuable component in the concentrate (P 2 O 5 = 31.23 %) and the recovery to concentrate of 95.22 % were obtained in the chamber product at amine consumption of 950.88 g/t and sodium tripolyphosphate consumption of 500 g/t.
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Date submitted2019-12-25
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Date accepted2020-06-30
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Date published2020-10-08
Accounting of geomechanical layer properties in multi-layer oil field development
Amid the ever-increasing urgency to develop oil fields with complex mining and geological conditions and low-efficiency reservoirs, in the process of structurally complex reservoir exploitation a number of problems arise, which are associated with the impact of layer fractures on filtration processes, significant heterogeneity of the structure, variability of stress-strain states of the rock mass, etc. Hence an important task in production engineering of such fields is a comprehensive accounting of their complex geology. In order to solve such problems, the authors suggest a methodological approach, which provides for a more reliable forecast of changes in reservoir pressure when constructing a geological and hydrodynamic model of a multi-layer field. Another relevant issue in the forecasting of performance parameters is accounting of rock compressibility and its impact on absolute permeability, which is the main factor defining the law of fluid filtration in the productive layer. The paper contains analysis of complex geology of a multi-layer formation at the Alpha field, results of compression test for 178 standard core samples, obtained dependencies between compressibility factor and porosity of each layer. By means of multiple regression, dependencies between permeability and a range of parameters (porosity, density, calcite and dolomite content, compressibility) were obtained, which allowed to take into account the impact of secondary processes on the formation of absolute permeability. At the final stage, efficiency of the proposed methodological approach for construction of a geological and hydrodynamic model of an oil field was assessed. An enhancement in the quality of well-by-well adaptation of main performance parameters, as well as an improvement in predictive ability of the adjusted model, was identified.
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Date submitted2020-04-24
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Date accepted2020-05-20
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Date published2020-10-08
Prospects and social effects of carbon dioxide sequestration and utilization projects
The issues of global warming and occurrence of the greenhouse effect are widely discussed on a global scale. Various methods of reducing greenhouse gas emissions are actively being investigated and tested, including technologies for sequestration of carbon dioxide, the implementation of which is carried out in the form of CC(U)S (carbon capture, utilization and storage) projects related to capture, disposal and, in some cases, use of CO 2 . In Russia, CC(U)S technologies are not yet used, but there is a significant potential for their development and distribution. CC(U)S technologies acquire a special role in the context of the development of the energy and industrial sectors of Russia, which are key sources of emissions, and the geological objects belonging to them are potential carbon storages. The purpose of this study is to conceptually analyze the CC(U)S technological cycle and typify such projects, assess the prospects for their implementation in Russia, and identify social effects from the implementation of CC(U)S projects. The main results of the study are presented in the form of a typology of CC(U)S projects, a strategic analysis of the prospects for introduction of such technologies in Russia, as well as development of approaches to assessing social effects with systematization and highlighting a set of indicators for their assessment, which can serve as a basis for re-estimation of the values of CC(U)S projects. The main research methods used were methods of decomposition, systematization and typology, as well as strategic analysis with a focus on relevant practical materials on the topic of the work. Directions for further research are related to the substantiation of the methodology for assessing social effects of CC(U)S projects, including for the conditions of Russia, based on the principles of balancing the interests of key participants.
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Date submitted2020-01-09
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Date accepted2020-01-20
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Date published2020-02-25
Mechanical Properties of Sandstone using non-Destructive Method
- Authors:
- H. Rajaoalison
- A. Zlotkowski
- G. Rambolamanana
The understanding of physical and mechanical properties of rock is considered as critical in drilling, geo-engineering, and construction applications. As an example, the awareness of these rock parameters contributes to avoid or minimizing instability around the wellbore while drilling. The laboratory experiment of understanding of these parameters can be done in two-different ways: static, where the sample subjects to destruction after the test and dynamic, known as non-destruction method. The non-destructive method using ultrasonic waves under a series of different stress conditions, starting from 7 to 56 MPa with incrementation of 7MPa, has been used in this paper in order to characterize the mechanical properties of dry Zbylutów sandstone at 20 and 80°C. The velocity of primary (P) and secondary (S) waves within these ranges has been recorded in order to understand the behavior of the mechanical properties. The results showed that the Young’s modulus, bulk modulus, shear modulus, and Lame’s constant of Zbylutów sandstone have a positive correlation with good coefficient correlation with the increased stress, while the Poisson’s ratio showed a negative correlation. Besides, the effect of temperature on the rock parameters is approved by the decrease of primary wave velocity in this two-different temperature range. Such results are necessary when preparing the appropriate mud weight for drilling process, which is related to wellbore instability.
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Date submitted2019-05-24
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Date accepted2019-07-15
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Date published2019-10-23
Effective Power and Speed of Mining Dump Trucks in Fuel Economy Mode
- Authors:
- V. I. Alexandrov
- M. A. Vasileva
- V. Y. Koptev
Existing methods for determining the effective power, based on the calculation of the average indicator operation of the engine during the piston stroke, do not take into account the change in thermodynamic parameters and the polytropic operation of the engine, the value of which depends on the polytropic efficiency of the duty cycle. This is the reason that the calculation of the effective power leads to some error – the margin of the engine features. The identification of this stock allows us to review the entire line of dump trucks in the direction of increasing their pass- port effective capacity, which will lead to a reduction in capital purchase costs due to the choice of a previously un- derestimated and cheaper option, as well as a reduction in current operating costs due to a decrease in the specific fuel consumption rate. Taking into account the stochastic nature of the transport process and assessing the influence of all external and internal factors when calculating the rational mode of operation of a mining truck can further reduce specific fuel consumption by choosing the rational speed of its movement in loaded and empty directions.
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Date submitted2018-04-26
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Date accepted2018-06-28
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Date published2018-10-24
Modern specificity of corporate relations on the example of vertical-integrated company
- Authors:
- A. A. Lapinskas
The article describes features of the modern model of Russian corporate relations on the example of a vertically integrated and diversified company. The CRs are still affected by the consequences of the privatization processes of state and municipal enterprises in the 1990s, which resulted in the emergence of a peculiar economic model of oligarchic capitalism and a specific model of CR. On a specific example, the pros and cons of this model are analyzed considering the processes of consolidation of entrepreneurial activities in the metallurgy and gold mining industry. The conclusion is made about the predominance of quasi-corporate relations, the ways to improve CR are suggested.
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Date submitted2017-09-10
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Date accepted2017-11-10
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Date published2018-02-22
Research of heat generation indicators of gas engines
- Authors:
- O. N. Didmanidze
- A. S. Afanasev
- R. T. Khakimov
A comprehensive strategy for reviving the production of mining industry equipment and ensuring its competitiveness includes the wide use of gas engines for various purposes. Experimental studies of the working cycle of a gas engine are one of the main tasks in determining the heat generation characteristics. To this end, indicator charts were recorded in various modes, which were subjected to analysis in order to determine the key parameters characterizing intra-cylinder processes. According to the experimental program, the maximum cycle pressure, the rate of pressure build-up, the heat generation characteristic, the first heat generation phase, the duration of the second combustion phase, and the effect of the ignition advance angle for the ignition period were determined. The results of an experimental study of the influence of gas engine working process with allowance for the change in the ignition advance angle for the ignition period are described and the parameters of the maximum cycle pressure, the rate of pressure build-up, and the heat generation characteristics are determined. In the processing of data, integral charts are constructed, the working cycle parameters are calculated, and the dynamics of the engine heat generation is determined.
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Date submitted2017-09-20
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Date accepted2017-10-29
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Date published2018-02-22
Substantiation of strength of the filling mass by taking a blast effect into account for the room-and-pillar methods
- Authors:
- E. T. Voronov
- V. N. Tyupin
The development of the uranium ore bodies at the ore mines of PJSC «Priargunsky Industrial Mining and Chemical Union» (PJSC «PIMCU») by room-and-pillar method as high as a pillar between the levels (60 m) without fill, as a rule, leads to the fall of the adjoining rock, to the strong contamination of the ore and to the high yield of the oversize pieces of the barren rock. A longstanding industrial and theoretical research shows that the sizes of the self-sustaining rock escarpments at the ore mines of PJSC «PIMCU» in the solid mass of trachydacites, conglomerates, sandstones, felsites are equal to 20-40 m. Moreover, the sizes of the self-sustaining rock escarpments depend to a great extent on the intensity of fracturing of the adjoining rocks. The stable size of the escarpment does not exceed 5-10 m for the rocks with the size of a jointing up to 0.05 m. Consequently, timely performance of the filling operations of the worked-out space of the chamber is important. However, the question then arises: which characteristic strength should the filling mass have? The calculations of the characteristics of the filling mass in compliance with the reference guide «Shaft filling operations» show underestimated values of the characteristic compressive strength of the fill (1.4 MPa) for the room-and-pillar method, which leads to the increase of the ore contamination by the fill and provokes the additional costs for refilling of the volumes of the rock fall. On the basis of the Russian experience of using of the consolidated fill for the development of the ore bodies of 15 m thickness by chamber method the strength of the fill is taken as 3-5 MPa under the resultant value of the static stresses without taking into account the character of the dynamic loading stresses induced by the sequence blasthole ring initiating in a chamber. Overestimating the characteristic strength of the filling mass results in the high consumption of the cementing materials. On the basis of the theoretical research the authors suggested the theoretical dependence of calculation of the characteristic strength of the filling material with respect to compressive stresses of the fill induced by the blasting operations. The process of designing of the filling mass with the zones of diverse strength for the room-and-pillar extraction with the consolidated rock fill is proven to be economically reasonable. The bottom zone of the solid mass should have high strength (3-4 MPa), and the strength of the upper zone should be up to 2-2.5 MPa.
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Date submitted2016-09-03
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Date accepted2016-11-24
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Date published2017-02-22
Research of compression strength of fissured rock mass
- Authors:
- A. G. Protosenya
- P. E. Verbilo
The article examines a method of forecasting strength properties and their scale effect in fissured rock mass using computational modelling with final elements method in ABAQUS software. It shows advantages of this approach for solving tasks of determining mechanical properties of fissured rock mass, main stages of creating computational geomechanic model of rock mass and conducting a numerical experiment. The article presents connections between deformation during loading of numerical model, inclination angle of main fracture system from uniaxial and biaxial compression strength value, size of the sample of fissured rock mass and biaxial compression strength value under conditions of apatite-nepheline rock deposit at Plateau Rasvumchorr OAO «Apatit» in Kirovsky region of Murmanskaya oblast. We have conducted computational modelling of rock mass blocks testing in discontinuities based on real experiment using non-linear shear strength criterion of Barton – Bandis and compared results of computational experiments with data from field studies and laboratory tests. The calculation results have a high-quality match to laboratory results when testing fissured rock mass samples.
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Date submitted2015-12-13
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Date accepted2016-02-02
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Date published2016-12-23
Corporate social responsibility in coal industry (practices of russian and european companies)
- Authors:
- T. V. Ponomarenko
- R. Volnik
- O. A. Marinina
Corporate social responsibility (CSR) is built on interaction between companies and the society which is especially important for major companies that exploit natural resources and play the role of city-forming socially significant entities. Various interpretations of the notion of social responsibility define the varying levels of influence companies have on the society, different levels of contribution of companies in the said process and the degree and level of implementation of CSR. The relations between social responsibility and economic results and the effects of implementing CSR policies are often not obvious. This study offers an assessment of present-day state of corporate social responsibility policies in coal companies of Russia and Poland and formulates proposals on implementing social responsibility projects with consideration of state-of-the-art CSR concepts. The results of the study are as follows: the achieved level of social responsibility in coal companies of Russia and Poland has been assessed; it is proven that most companies in the coal industry are at the level of fragmentary application of CSR concepts; an analysis has been carried out of tools available in the area of social responsibility of coal companies.
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Date submitted2015-12-29
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Date accepted2016-02-21
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Date published2016-12-23
Poorly studied phenomena in geoelectrics
- Authors:
- V. S. Mogilatov
Undoubtedly, modern geoelectric technologies emerge in the result of the development of traditional approaches and techniques. However of more interest is the appearance of completely new technologies based on new effects and new models of interaction of geological medium and electromagnetic field. The author does not commit to indicate principally new directions, but only wants to discuss some poorly known facts from the theory and practice of geoelectrics. The outcome of this study could be considered attracting the attention of experts to non-traditional signals in geoelectrics. The reviewed phenomena of interest, not fully implemented in practice in the author’s opinion, are field split into two polarizations: transverse electric (the ТЕ-field) and transverse magnetic (the ТМ-field), then some poorly known properties of ТМ-field, the role of bias currents, the anisotropy of horizontal resistances, the role of geomagnetic field in geoelectric sounding, the unique resolution of CSEM (Controlled Source Electro-Magnetic) techniques at sea.
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Date submitted2014-12-20
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Date accepted2015-02-05
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Date published2015-12-25
Synergetic changes of tribochemical properties in the heterogeneous systems containing surface modified metals
- Authors:
- A. G. Syrkov
In the article tribochemical properties and synergetic effects in lubricants with metal addi-tives, characterized by surface modifcations, have been analysed. The priority results of measur-ings friction coefficient (f) and friction force (F fr) are given for heterogeneous systems in the form of И-20 oil with solid Al-additives, contatiing dispersed aluminium, with surface-modified triamon (Т), alkamon (A) and ethylhydridsiloxane according to various programs. It has been educed that with all other things being equal, triamon underlayers introduction into Al-additives with the external chemisorpted ethylhydridsiloxane layer results in the decrease of F fr and f in the system in proportion to the Т-underlayer number reduction from three to one. It has been discovered that the use of low-molecular Т-underlayer in Al-additives is a delicate method of summand value regulation (from 10,8 to 13,2 Н), accountable for intermolecular forces in the boundary fritction equation in the tribological pair applied.
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Date submitted2010-07-12
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Date accepted2010-09-14
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Date published2011-03-21
Principles of an automatic control system of ventilation creation the kuznetsovsky railway tunnel
- Authors:
- S. G. Gendler
- V. A. Pleskunov
For effective ventilation Kuznetsovsky railway tunnel the longitudinal scheme of ventilation based on use of jet fans is offered. It is shown that use of the offered scheme of ventilation at influence of natural draft and piston effect of trains is impossible without an automatic control system of ventilation (ACSV). The principles of work ACSV taking into consideration natural and operational factors are proved.
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Date submitted2009-09-24
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Date accepted2009-11-02
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Date published2010-06-25
Oral presentation skills forming. Technical university undergraduates and phd students foreign language teaching а posteriori
- Authors:
- A. A. Petrova
The article is dedicated to the educational methods of oral presentation in foreign language practical skills forming.
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Date submitted2009-07-18
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Date accepted2009-09-30
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Date published2010-04-22
Account of stress gradients in rock mass in designing of mining constructions
- Authors:
- S. V. Suknyov
- M. D. Novopashin
Using the gradient approach the criteria of shear and tensile cracking are developed in compression under conditions of stress concentrations near mine workings. Considering the size effect, a function type of local strength is determined, expressions for critical pressure are derived and comparison between analytical and experimental data is performed.
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Date submitted2008-11-23
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Date accepted2009-01-30
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Date published2009-12-11
The estimate of the utilization’s efficiency of the production waste products, which appeared as a result of the preservation of the environment measures
- Authors:
- E. M. Pronin
Nowadays the problems of the stable growth of mineral and source of raw materials and fuel and energy complex industries are attached great importance to, since it influences the country social-economic condition. In its turn the development of the mining industry requires opening up new lands, which are especially vulnerable to different kinds of anthropogenous and technogenous factors. The changes in the state of economic system have excluded the lowering expenditure by the economy of the production scale. The typical features of a new economy became the progress of free competition and intensive demonopolization. At the same time for the mining industry it is significant that large-scale enterprises should be the foundation of many cities economies of the Russian Federation. For the way out of a system crisis it is necessary to change the strategy – to alter not only the condition of the system, but its management. The formation of the mining complexes permits to use sources of raw materials of the exploited deposits in the proper way, to process waste products of the basic production into the commodity output, to raise the efficiency and cut costs of the preservation of the environment measures from concentration waste products, exhaust solutions, gases, warm water harmful influence on the environment. The practical use of the production waste products of the mining complexes is unprofitable and makes sense only because of its opportunity partially compensating the aggregate investments for the preservation of the environment. The estimate of the utilization s efficiency of the production waste products has made.