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Date submitted2017-03-25
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Date accepted2017-05-06
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Date published2017-08-27
Prospects of gas hydrate presence in the Chukchi sea
The purpose of this study is to forecast the scale and distribution character of gas hydrate stability zone in the Chukchi Sea under simulated natural conditions and basing on these results to estimate resource potential of gas hydrates within this area. Three types of stability zone have been identified. A forecast map of gas hydrate environment and potentially gas hydrate-bearing water areas in the Chukchi Sea has been plotted to a scale of 1:5 000 000. Mapping of gas hydrate stability zone allowed to give a justified forecast based on currently available data on geologic, fluid dynamic, cryogenic, geothermal and pressure-temperature conditions of gas hydrate formation in the Chukchi Sea. It is the first forecast of such kind that focuses on formation conditions for hydrates of various types and compositions in the Arctic seas offshore Russia. Potential amount of gas, stored beneath the Chukchi Sea in the form of hydrates, is estimated based on mapping of their stability zone and falls into the interval of 7·10 11 -11.8·10 13 m 3 .
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Date submitted2017-03-21
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Date accepted2017-04-30
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Date published2017-08-27
Petrophysical approach to electrical properties of loose soils
- Authors:
- V. A. Shevnin
- D. A. Kvon
- A. A. Ryzhov
The paper focuses on the relation between geoelectrical characteristics of the soil: resistivity, polarizability and normalized polarizability (ρ, η, M n ) – and its superficial conductivity (SC or σ") using methods of vertical electrical sounding with induced polarization (VES-IP), electric profiling with induced polarization (EP-IP) and frequency characteristic (FC-IP). The authors demonstrate that superficial conductivity can be determined not only from spectral IP data, but also from soil resistivity obtained through petrophysical measurements. In this case normalized polarizability (M n ) is equal to superficial conductivity (SC). Superficial conductivity, in its turn, is proportionate to clay content of the soil. Increasing clayiness reduces hydraulic conductivity. It has been demonstrated that interpretation of EP-IP results benefits from combined study of the plots of three abovementioned parameters (ρ, η, M n ). In the aeration zone, incomplete humidity has a significant effect on geoelectrical parameters of the soil. Petrophysical modelling helps to investigate the impact of humidity.
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Date submitted2017-03-07
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Date accepted2017-05-05
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Date published2017-08-27
Results of cement-to-rock contact study
- Authors:
- N. I. Nikolaev
- Lyu Khaoya
The paper focuses on the problems of oil and gas well cementation. It has been established that the main reason why formation fluids leak behind the casing is due to poor isolation of the annulus caused by incomplete cleaning of the filter cake, which results in weak or absent adhesion between the cement and the rock. The authors demonstrate that adding polymer modifier GM-II to the spacer fluid strengthens the cement-to-rock contact by several times. Moreover, mixing spacer with cement slurry does not degrade such important properties as spreadability and consistency of the latter. The paper contains investigation results on the content of polymer spacers that improve cementation quality of oil and gas wells. Spectral infrared and X-ray analysis allowed to define the impact of phase composition and mineral structure of the system «cement stone-filter cake-formation rock» on improving leak tightness of the annulus. Electron microscopic study showed that the use of polymer spacers facilitates formation of felted net-like structures between hydrated minerals. The composition of these structures, binding cement grains and clay minerals, has been studied by means of energy dispersive X-ray microanalysis. Obtained results allow to come to the conclusion that these structures mostly consist of hydrated calcium silicate (more than 77% by mass), which agrees well with the findings of infrared and X-ray analysis. Pilot tests, performed at the Shengli oil field in China, have confirmed efficiency of developed spacer fluids.
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Date submitted2017-03-28
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Date accepted2017-05-16
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Date published2017-08-27
Mathematical modeling of seismic explosion waves impact on rock mass with a working
In the article, within the framework of the dynamic theory of elasticity, a mathematical model of the impact of seismic blast waves on rock mass is presented, including a working. The increase in the volume of mining operations in complex mining and geological conditions, taking into account the influence of the explosion energy, is closely connected with the analysis of the main parameters of the stress-strain state of the rock massif including a working. The latter leads to the need to determine the safe parameters of drilling and blasting operations that ensure the operational state of mining. The main danger in detonation of an explosive charge near an active working is a seismic explosive wave which characteristics are determined by the properties of soil and parameters of drilling and blasting operations. The determination of stress fields and displacement velocities in rock mass requires the use of a modern mathematical apparatus for its solution. For numerical solution of the given boundary value problem by the method of finite differences, an original calculation-difference scheme is constructed. The application of the splitting method for solving a two-dimensional boundary value problem is reduced to the solution of spatially one-dimensional differential equations. For the obtained numerical algorithm, an effective computational software has been developed. Numerical solutions of the model problem are given for the case when the shape of the working has a form of an ellipse.
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Date submitted2017-03-20
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Date accepted2017-05-24
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Date published2017-08-27
Determination of parameters of the underground inclined coal seam mining in Quang Ninh basin under protected objects on the surface
- Authors:
- Le Van Khau
Based on analysis of mining and geological conditions of natural occurrence of coal seams at Quang Ninh basin it has been determined that more than 37 % of deposit reserves are located under the protected surface objects. To justify the possible variants of technological schemes for development of these coal seams situated under protected surface objects there has been a methodology for evaluation of displacement parameters of undermined layer during underground mining operations. The article shows the possibility to perform calculations for this methodology that originally were developed for coal deposits in Russia and to use calculated coefficients for Bulanashskoe deposit (Ural), because its mining and geological conditions of natural occurrence for coal seams are similar to the conditions of occurrence at Quang Ninh basin. It also presents the research results for possibility to apply the development systems to mine the reserves located under protected surface objects using the technological schemes with roof control, with complete caving, full backfilling and pillar roof support. It has been identified that with a system of roof support using complete caving the deformation of surface exceed the critical values required for preservation of surface objects. In case of using the development technology with full backfilling there have been defined a minimal admissible coefficient of backfilling, as well as requirements to filling materials. For coal deposit mining technology using the method of pillar roof support there have been defined parameters for pillars and chambers, identified maximum admissible extraction ratio ensuring protection and safety of objects located on the surface. It also presents the algorithm for selection of technological mining scheme for development of coal seams of Quang Ninh basin.
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Date submitted2017-03-19
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Date accepted2017-05-15
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Date published2017-08-27
Coal industry in Mongolia: status and prospects of development
- Authors:
- Ochirbat Punsalmaagiin
Currently, Mongolia ranks 10 th place in the world in terms of coal reserves. According to the Ministry of Mineral Resources and Energy of Mongolia, the total explored coal reserves in the country amount to 150 billion tons. The Government of Mongolia considers the development of industrial coal processing industry to be one of the most important strategic directions of its activity. At present, the Cabinet of Ministers of Mongolia has developed a target program for the development and support of projects for the production of synthetic fuel from coal. At the same time, foreign companies are waiting for the government of Mongolia to provide a stable and favorable environment for conducting business. The article deals with the issues related to the current state of coal industry in Mongolia, as well as prospects for the development of this industry, the expected levels of increase in production and changes in the structure of coal use.
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Date submitted2017-03-09
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Date accepted2017-05-12
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Date published2017-08-27
Electrowinning of cobalt from sulfate-chloride and sulfate solutions of cobalt and manganese under dynamic conditions
- Authors:
- L. P. Khomenko
- L. A. Voropanova
- Z. A. Gagieva
The design of an electrolyzer for electrowinning in dynamic conditions is developed. The dependence of the results of electrowinning of cobalt and manganese from sulfate and sulfate-chloride solutions under dynamic conditions using a titanium cathode and a lead anode with 1 % of silver was studied. It was found that the best extraction results for the current yield and the specific energy consumption were obtained by electrolysis from sulfate solutions at a low concentration of manganese in an electrolyser without a perforated baffle plate separating the cathode and anode spaces.
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Date submitted2017-03-24
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Date accepted2017-05-21
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Date published2017-08-27
Dynamic stabilization of machining process based on local metastability in controlled robotic systems of CNC machines
- Authors:
- V. V. Maksarov
- Yu. Olt
The paper describes an effective method, which permits to control the machining of hard-to-handle materials under local pre-strain and facilitates generation of structural metastability on the outer layer of the process material. Authors propose a new approach to creating local metastability in the machined material using thermal, plastic and cryogenic treatment. Changes in material properties, occurring under local deformation, are presented in a widely used graphic form of a stress-strain curve. In experimental tests, performed under local plastic strain, the authors observed normal vibration displacement of the tool in relation to the surface of the workpiece, made of medium-carbon steel (0.45 % C). Theoretical and experimental results confirmed the possibility to control the cutting process and to deliver dynamic stability for high-precision machining. The study allows to improve existing technologies for a wide range of materials and cutting modes, to implement segmentation and breaking of the chip in the shear zone, and to apply controlled robotic systems on CNC machines.
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Date submitted2017-03-07
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Date accepted2017-05-11
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Date published2017-08-27
Problems and solutions of reliability issues for external power supply in the coal mines
- Authors:
- I. Yu. Semykina
- E. V. Skrebneva
Restructuring of the energy sector and liberalization of the electricity market resulted in separation of a single industry into a multitude of generating companies, federal and interregional distribution utilities, regional power providers and energy suppliers. For a number of reasons, related to the process of managing separate companies, faults in the laws and regulations, and unsatisfactory technical state of the energy equipment both on the part of distributors and consumers, reliability of energy supply faces increasing negative trends, which potentially can lead to big problems. Up to this day the energy sector does not have a developed database on the state of equipment and results of its maintenance, nor has it defined criteria to actually assess technical conditions of the equipment. The authors propose to develop and implement a mechanism aimed at technical auditing and monitoring of the engineering state of external power supply system, whose results can help in the development of more efficient and economically sound measures to improve reliability of energy supply. In recent years, a lot of attention has been paid to the issues of enhanced security of industrial power supply. However, specific characteristics of underground coal mining and enormous work load of the production process limit the applicability of developed methods and algorithms. Existing research does not address economic issues of reliable energy supply, either direct (economic damage from power interruptions, contractual security of supply, tariff regulation) or indirect (charges for utility connection with a required level of reliability). There is no explicit definition for the term «autonomous energy source», nor is there a list of power receivers falling into the first and «special» categories according to their reliability. The paper contains a range of urgent problems and solutions that will increase reliability of external power supply in the coal mines.
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Date submitted2017-03-22
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Date accepted2017-05-26
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Date published2017-08-27
Improvement of threaded joint reliability by means of electromechanical processing
- Authors:
- L. V. Fedorova
- Yu. S. Ivanova
- M. V. Voronina
The paper presents technological schemes of electromechanical processing (EMP) and examines formation specifics of high strength steel structures in the area of thermomechanical highly-concentrated strain on the root and flanks of external and internal threads. Testing results of EMP implementation are described. Materials of this paper are of practical value to specialists in various fields, related to the issues of improving threaded joint reliability.
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Date submitted2017-03-04
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Date accepted2017-05-20
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Date published2017-08-27
Topological interlocking as a principle of engineering design in consruction of marine and coastal structures
- Authors:
- V. Yu. Piirainen
- Yu. Z. Estrin
As a discussion contribution, a new concept for solving problems of bank protection structures based on topological interlocking is presented, which opens up a way to obtaining new segmented or modular designs of building elements and structures. The relevance of the modular design principle based on the use of natural laws of harmonization of artificially created forms is justified. In this concept, the idea of Platonic solids is further developed in a quest for new types of harmony and practical technological and engineering design applications at macro scale. The ever growing capabilities of modern building materials and technologies make it possible to create new construction systems on the basis of the modular principle, one of the most interesting forms of which is topological interlocking. This innovative principle of engineering design and its many advantages are considered in relation to bank protection structures. Variants of new promising designs based on topological interlocking are presented.
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Date submitted2017-03-28
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Date accepted2017-05-24
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Date published2017-08-27
Legal challenges of the new energy policy in Germany
- Authors:
- Marian Pashke
German Energiewende has substantially changed the electricity mix in Germany. Green electricity from wind, solar, water and biomass now provides the largest contribution to the total electricity consumption. In this respect, Energiewende can be regarded as an overall success. But in parallel to this scenario, a critical discourse has evolved concerning socio-political, economic and legal issues. The congruence of objectives and measures – for example, in regards to ensuring security of supply, expansion of electricity networks, development of electricity price and environmental consequences – in the course of expansion of electricity generation from renewable sources is the main focus of socio-political and economic discussions. Accelerated phase-out of nuclear energy and constitutional disputes regarding the legality of national orientation of the promotional scheme for green electricity in respect to the integration of German electricity sector in the European internal market for energy are in the centre of the debate and have a remarkable impact on the energy policy in Russia as well. Against this background, present article examines the contribution of German Energiewende to the resolution of complex challenges of the developed industrial society.
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Date submitted2017-03-09
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Date accepted2017-05-05
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Date published2017-08-27
Challenges and trends of quality management in the context of industrial and mineral resources economy
- Authors:
- V. P. Semenov
- Yu. I. Mikhailov
The paper reviews key challenges and trends of quality management in the context of industrial and mineral resources economy, from the beginning of research on quality to organization of modern systems, based on principals of total quality management. Attention is given to relevant issues, associated with the application of process and project approaches to quality management and with international management system standards. The authors present a list of key modern methods, instruments and concepts of quality management in the context of industrial and mineral resources economy. The paper reviews modern trends in the development of quality management, including formation and development of integrated management systems, control over the reproduction of intellectual capital under the conditions of global market and development of innovation economy.
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Date submitted2017-03-03
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Date accepted2017-05-13
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Date published2017-08-27
3D-diagnostics of function of electron distribution in plasma
- Authors:
- A. S. Mustafaev
- A. A. Strakhova
The paper gives further development of the method of a plate single-sided probe, which makes it possible to reconstruct the total electron velocity distribution function in an axially symmetric nonequilibrium plasma with an arbitrary degree of anisotropy. The method is improved for plasma diagnostics without the assumption of any symmetry. The theory of the method is developed and analytical relations are obtained connecting the Legendre components of the second-order derivative of the probe current with respect to the potential of the probe and the electron distribution function. The method is experimentally tested in the plasma of a positive column of a helium glow discharge. New possibilities of the method for investigating plasma near the boundaries are demonstrated and non-traditional information is obtained on the processes of escape of charged particles from the plasma volume on the walls.
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Date submitted2017-03-08
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Date accepted2017-05-17
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Date published2017-08-27
Control of inhomogeneous materials strength by method of acoustic emission
- Authors:
- V. V. Nosov
The ambiguous connection between the results of acoustic emission control and the strength of materials makes acoustic-emission diagnosis ineffective and actualizes the problem of strength and metrological heterogeneity. Inhomogeneity is some deviation from a certain norm. The real object is always heterogeneous, homogeneity is an assumption that simplifies the image of the object and the solution of the tasks associated with it. The need to consider heterogeneity is due to the need to clarify a particular task and is a transition to a more complex level of research. Accounting for heterogeneity requires the definition of its type, criterion and method of evaluation. The type of heterogeneity depends on the problem being solved and should be related to the property that determines the function of the real object, the criterion should be informative, and the way of its evaluation is non-destructive. The complexity of predicting the behavior of heterogeneous materials necessitates the modeling of the destructive process that determines the operability, the formulation of the inhomogeneity criterion, the interpretation of the Kaiser effect, as showing inhomogeneity of the phenomenon of non-reproduction of acoustic emission (AE) activity upon repeated loading of the examined object. The article gives an example of modeling strength and metrological heterogeneity, analyzes and estimates the informative effect of the Kaiser effect on the danger degree of state of diagnosed object from the positions of the micromechanical model of time dependencies of AE parameters recorded during loading of structural materials and technical objects.
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Date submitted2017-03-24
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Date accepted2017-05-15
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Date published2017-08-27
Application of electronic learning tools for training of specialists in the field of information technologies for enterprises of mineral resources sector
- Authors:
- E. V. Katuntsov
- Ya. Kultan
- A. B. Makhovikov
The article shows the advantages of using modern electronic learning tools in the training of specialists for the mineral and raw materials complex and considers the basic principles of organizing training using these tools. The experience of using electronic learning tools using foreign teaching materials and involving foreign professors is described. A special attention is given to the electronic learning environment of the Cisco Networking Academy – Cisco NetAcad. The experience of teaching at the Networking Academy of the Saint-Petersburg Mining University is described. Details are given to modern virtual environments for laboratory work, such as Cisco Packet Tracer, GNS3 and Emulated Virtual Environment. The experience of using electronic learning technologies at the University of Economics of Bratislava is considered. It actively cooperates with a number of universities of other countries, such as the University of International Business (Almaty), the Eurasian National University named after LN Gumilyov (Astana) and the Institute of Social and Humanitarian Knowledge (Kazan).