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Date submitted2022-04-14
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Date accepted2022-07-21
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Date published2022-11-03
Technological mineralogy: development of a comprehensive assessment of titanium ores (exemplified by the Pizhemskoye deposit)
Technological mineralogy of titanium ores is the basis for assessing their complexity. It enables, from a unified standpoint, to trace the entire course of changes in mineral matter through operating procedures, including beneficiation, processing, and obtaining target industrial products. The study targets are Pizhemskoye ilmenite-leucoxene sandstones, which are distinguished by a complex polymineral composition. Along with the main ore components, there are other metals with different speciation (isomorphic admixture, independent mineral phases). The optimal set of mineralogical analysis methods for the predictive assessment of their further use is substantiated exemplified by titanium ores of the Pizhemskoye deposit, which are complex, noted for a variable content of iron oxides and contain rare earth metals. Examinations by X-ray phase analysis and scanning electron microscopy confirm that the main titanium phases of sandstones are pseudorutile and a polymineral aggregate, “leucoxene”. Considering the granulometric peculiarities of the magnetic and non-magnetic fractions of the gravity concentrate, the prospects of technologies for processing titanium raw materials are discussed. Along with the problems of obtaining high-quality raw materials, the transformations of mineral phases as a result of extreme impacts and their physicochemical properties as a consequence of isomorphic substitution of a part of Ti atoms with natural modifier agents (Fe and V) in the synthesis of titanium oxide nanostructures for industrial applications are considered (photocatalytic nanoreactor).
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Date submitted2022-02-22
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Date accepted2022-09-15
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Date published2022-11-10
The problem of the genesis of the Mesoarchean aluminosilicate rocks from the Karelian craton and their possible use as a quartz-feldspar raw material
The article presents original data obtained in the study of the chemical and mineral compositions of the Late Archean aluminosilicate rocks (formerly called silicites) from the Koikari and Elmus structures of the Vedlozero-Segozero greenstone belt of the Karelian craton (Central Karelia). A comprehensive study of these formations revealed their complex genesis as a result of the late imposition of hydrothermal and metamorphic alteration on sedimentary and volcanic-sedimentary rocks of feldspar-quartz composition. Due to the superimposed metasomatic (temperature?) impact on feldspar-quartz siltstones, Fe was removed from microinclusions in quartz and feldspar and its oxides were concentrated along the grain boundaries. Minerals such as monazite, parisite, allanite are also located either along the grain boundaries of quartz and feldspars, or together with calcite they fill microfractures, which makes it possible to get rid of them when preparing quartz-feldspar concentrates using various beneficiation technologies. According to most indicators limited by GOSTs, individual samples in their natural form meet the requirements for quartz-feldspar raw materials for use as part of batch in the production of diverse types of glass. Additional beneficiation of the feedstock (grinding, screening into narrow classes and further magnetic separation) leads to a decrease in Fe 2 O 3 content to normalized values. The resulting quartz-feldspar concentrates with various particle sizes can be used in the production of building material and fine ceramics (sanitary and ceramic products, facing and finishing tiles, artistic, household porcelain and faience). The homogeneity of the mineral and chemical composition, the possibility of compact extraction and beneficiation (including in mobile small-sized installations) increase the prospects and competitiveness of this non-traditional feldspar raw material from Central Karelia.
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Date submitted2020-11-16
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Date accepted2021-03-02
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Date published2021-04-26
Determination and verification of the calculated model parameters of salt rocks taking into account softening and plastic flow
The article suggests using a combination of the modified Burgers model and the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient to determine the parameters of salt rocks. A comparative analysis of long-term laboratory tests and field observations in underground mine workings with the results obtained using a calculated model with certain parameters is carried out. The parameters of the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient were obtained from the statistically processed data of laboratory tests, and the parameters of the modified Burgers model were determined. Using numerical methods, virtual (computer) axisymmetric triaxial tests, both instantaneous and long-term, were performed on the basis of the proposed model with selected parameters. A model problem is solved for comparing the behavior of the model with the data of observation stations in underground mine workings obtained from borehole rod extensometers and contour deformation marks. The analytically obtained coefficients of the nonlinear viscous element of the modified Burgers model for all the analyzed salt rocks did not need to be corrected based on the monitoring results. At the same time, optimization was required for the viscoelastic element coefficients for all the considered rocks. The analysis of the model studies showed a satisfactory convergence with the data on the observation stations. The comparative analysis carried out on the models based on laboratory tests and observations in the workings indicates the correct determination of the parameters for salt rocks and the verification of the model in general.
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Date submitted2021-01-20
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Date accepted2021-03-15
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Date published2021-04-26
Improving the quality of electricity in the power supply systems of the mineral resource complex with hybrid filter-compensating devices
- Authors:
- Yurii A. Sychev
- Roman Yu. Zimin
The urgency and necessity of choosing and justifying the structures of hybrid filter-compensating devices based on series and parallel active filters to improve the quality of electricity in the power supply systems of enterprises of the mineral resource complex is shown. Mathematical models of hybrid filter compensating devices based on parallel and series active filters have been developed. Based on these mathematical models, computer simulation models of the indicated hybrid structures have been developed. The results of simulation showed the effectiveness of the correction of power quality indicators in terms of reducing the level of higher harmonics of current and voltage, as well as voltage deviations. The degree of influence of filter-compensating devices on the power quality indicators, which determine the continuity and stability of the technological process at the enterprises of the mineral resource complex, have been revealed. It has been established that a hybrid filter-compensating device based on a parallel active filter can reduce the level of higher harmonics of current and voltage by more than 90 and 70 %, respectively, and based on a series active filter, it can reduce the level of higher harmonics of voltage by more than 80 %. Based on the simulation results, the possibility of compensating for the reactive power of a hybrid structure based on parallel active and passive filters has been revealed. The possibility of integrating hybrid filter-compensating devices into more complex multifunctional electrical systems for the automated improvement of the quality of electricity is substantiated, as well as the expediency and prospects of their use in combined power supply systems based on the parallel operation of centralized and autonomous sources of distributed generation.
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Date submitted2020-06-13
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Date accepted2020-06-14
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Date published2020-06-30
Deep structure and geodynamic conditions of granitoid magmatism in the Eastern Russia
- Authors:
- Viktor I. Alekseev
We investigated the deep structure of the lithosphere and the geodynamic conditions of granitoid magmatism in the Eastern Russia within the borders of the Far Eastern Federal District. The relevance of the work is determined by the need to establish the geotectonic and geodynamic conditions of the granitoids petrogenesis and ore genesis in the Russian sector of the Pacific Ore Belt. The purpose of the article is to study the deep structure of the lithosphere and determine the geodynamic conditions of granitoid magmatism in the East of Russia. The author's data on the magmatism of ore regions, regional granitoids correlations, archive and published State Geological Map data, survey mapping, deep seismic sounding of the earth's crust, gravimetric survey, geothermal exploration, and other geophysical data obtained along geotraverses. The magma-controlling concentric geostructures of the region are distinguished and their deep structure is studied. The connection of plume magmatism with deep structures is traced. The chain of concentric geostructures of Eastern Russia controls the trans-regional zone of leucocratization of the earth's crust with a width of more than 1000 km, which includes the Far Eastern zone of Li-F granites. Magmacontrolling concentric geostructures are concentrated in three granitoid provinces: Novosibirsk-Chukotka, Yano-Kolyma, and Sikhote-Alin. The driving force of geodynamic processes and granitoid magmatism was mantle heat fluxes in the reduced zones of the lithospheric slab. The distribution of slab windows along the Pacific mobile belt's strike determines the location of concentric geostructures and the magnitude of granitoid magmatism in the regional provinces. Mantle diapirs are the cores of granitoid ore-magmatic systems. The location of the most important ore regions of the Eastern Russia in concentric geostructures surrounded by annuli of negative gravity anomalies is the most important regional metallogenic pattern reflecting the correlation between ore content and deep structure of the earth's crust.
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Date submitted2019-09-04
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Date accepted2019-12-25
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Date published2020-04-24
Composition of spherules and lower mantle minerals, isotopic and geochemical characteristics of zircon from volcaniclastic facies of the Mriya lamproite pipe
The article presents the results of studying the rocks of the pyroclastic facies of the Mriya lamproite pipe, located on the Priazovsky block of the Ukrainian shield. In them the rock's mineral composition includes a complex of exotic mineral particles formed under extreme reduction mantle conditions: silicate spherules, particles of native metals and intermetallic alloys, oxygen-free minerals such as diamond, qusongite (WC), and osbornite (TiN). The aim of the research is to establish the genesis of volcaniclastic rocks and to develop ideas of the highly deoxidized mantle mineral association (HRMMA), as well as to conduct an isotopic and geochemical study of zircon. As a result, groups of minerals from different sources are identified in the heavy fraction: HRMMA can be attributed to the juvenile magmatic component of volcaniclastic rocks; a group of minerals and xenoliths that can be interpreted as xenogenic random material associated with mantle nodules destruction (hornblendite, olivinite and dunite xenoliths), intrusive lamproites (tremolite-hornblende) and crystalline basement rocks (zircon, hornblende, epidote, and granitic xenoliths). The studied volcaniclastic rocks can be defined as intrusive pyroclastic facies (tuffisites) formed after the lamproites intrusion. Obviously, the HRMMA components formed under extreme reducing conditions at high temperatures, which are characteristic of the transition core-mantle zone. Thus, we believe that the formation of primary metal-silicate HRMMA melts is associated with the transition zone D".
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Date submitted2018-11-23
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Date accepted2019-01-03
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Date published2019-04-23
Structural model and tectonic evolution of the fault system in the Southern part of the Khur area, Central Iran
- Authors:
- A. Sohrabi
- A. Nadimi
- I. V. Talovina
- H. Safaei
In the southern part of the Khur area, there is faults system with predominantly North-West strike. This network of tectonic disturbances is one of the most important fault systems in Central Iran which crosses Paleozoic metamorphic rocks, Cretaceous limestones, and Eocene volcanic rocks. Interpretation of satellite imagery ETM+ (Enhanced Thematic Mapper plus, Landsat) and field observations showed the presence of left-lateral shifts along with fault system. This formed the structure of the branch faults at the northeast end of the main fault. Another feature associated with shear dislocations is the rotation of blocks in the northeastern and southwestern segments of the area under study. There are several basins and positive structures within the area such as a series of uplifts and thrusts, indicating the presence of compressional and extensional tectonics. Another part of the work is devoted to the study of the correlation between active faults and earthquakes. Processing of satellite images, field observations, records of micro-earthquakes within a radius of 17 km made it possible to analyze the earthquakes parameters and the position of tectonic disturbances, and, as a result, confirm the presence of active faults in the region. In addition, we have identified three successive stages of the Khur area tectonics: rifting, contraction, change of convergence and uplift direction.
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Date submitted2018-05-14
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Date accepted2018-07-01
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Date published2018-10-24
Method for forecast of surface deformation during excavation operations in restraint urban conditions using the slurry trench technique
- Authors:
- P. A. Demenkov
- L. A. Goldobina
- O. V. Trushko
The article suggests the method for forecast of surface deformation during excavation operations in restraint urban conditions using the slurry trench technique based on FEM simulation. The results of numerical simulation of the construction of a semi-underground structure with slurry trench technique are given. The regularities of the change in the stress-strain state are determined depending on the trench parameters and the physical-mechanical properties of the soils. The work presents the troughs of surface subsidence during the construction of an excavation using the slurry trench technique, the diagrams of bending moments, transverse and longitudinal forces arising in the trench. Numerical experiments in Plaxis 2D and 3D were performed to estimate the discrepancy between modeling results in a plane and volumetric formulation of the problem.
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Date submitted2017-10-25
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Date accepted2018-01-17
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Date published2018-04-24
Innovative technology of large-size products manufacture
- Authors:
- S. N. Sanin
- N. A. Pelipenko
Advantages and prospects for the use of mobile robotic machine-tools in the manufacture of large parts in the mining, cement and nuclear industries are considered, as well as the importance of using welded structures to reduce production costs. Schemes for finishing mechanical machining of welded large-sized parts such as bodies of revolution with the use of mobile robotic machine-tools equipped with a belt-grinding tool, an enlarged description of the technological process for manufacturing a large-sized shell of a welded structure are presented. The conclusion is made that it is necessary to take into consideration the use in the industry of frameless production technology, especially for the machining of large-sized parts, and the use of small mobile robotic machine-tools is a productive approach and has a prospective character. The technological approaches proposed in the article make it possible to remove the restriction on the overall size and mass of the parts being manufactured, which are proposed to be manufactured directly at the site of future operation. The effectiveness of this technology is confirmed both by theoretical research and by practical data of the authors. It was noted that the production by the domestic machine-tool industry of mobile universal and special robotic machine-tools will allow the country's engineering industry to be brought to a new, high-quality world level.
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Date submitted2010-07-29
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Date accepted2010-09-02
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Date published2011-03-21
The depth estimation of 2D conductive isometrical bodies by singular points at the tipper frequency characteristic
- Authors:
- E. Yu. Ermolin
- O. Ingerov
The relation between parameters of 2D anomaly body and features of vertical sections of tipper amplitude are considered in this paper. According to investigations the depth of center, top and bottom of conductive body is connected with geometrical distance between two symmetrically located positive extremes in tipper pseudo-sections. In addition the tipper amplitude in extremes decreases on account of increasing depth of anomalous body. The described regularities can be used for MT projects planning and quantitative estimation of anomalous body parameters using tipper pseudo-section constructed from field data.
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Date submitted2010-07-13
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Date accepted2010-09-25
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Date published2011-03-21
Hydrogeological typisation of the north part of the Mid-Atlantic ridge
- Authors:
- M. V. Krivitskaya
The deep basite-hyperbasite rocks wich are special features for the north part of the Mid-Atlantic Ridge (MAR) are observed. The hydrogeological structures of the MAR are distinguished.
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Date submitted2009-09-26
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Date accepted2009-11-25
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Date published2010-06-25
Interaction of lexical and grammatical aspects in foreign languages teaching (the beginner level)
- Authors:
- A. N. Spiridonov
- K. V. Fedorov
The article studies further broadening and sophistication of mastered lexico-grammatical material through use of modality and The Sequence of Tenses which helps students to produce more complex syntactic structures and enhance the speech act.
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Date submitted2009-08-03
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Date accepted2009-10-30
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Date published2010-02-01
Geotechnical engineering features of the estimation of stability of heavy constructions of designed cement works in Novorossiysk
- Authors:
- Yu. V. Khaliullina
In the paper possibilities of constructing industrial heavy structures near slopes are described. The influence of tectonics, seismicity, a relief, deposit rocks thicknesses, their physical properties of geotechnical engineering feature are analyzed. The law of marls durability change is established. Positions of the most probable surfaces of sliding in cracked monoclonal deposit thickness are shown. The estimation of stability of the loaded slopes is made. Some recommendations for maintenance of structure stability are given.
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Date submitted1951-07-10
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Date accepted1951-09-12
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Date published1952-03-26
On the issue of protecting structures from the harmful effects of underground mining in coal and shale deposits with an unexplored nature of rock movement
- Authors:
- D. A. Kazakovskii
Until now, at newly developed deposits and at operating deposits with an unexplored nature of rock movement, the calculation of safety pillars in accordance with the recommendation of the "Rules for the Technical Operation of Mines" was carried out by analogy with other more or less studied deposits. However, there were no instructions on the selection of analog deposits, which could not but lead to an incorrect choice of parameters for calculating safety pillars. At present, it seems possible to give some guidelines on the selection of analog deposits based on accumulated factual data. These instructions can be used in calculating pillars during the design of mines and at operating deposits with an unexplored nature of rock movement. They can also be useful in calculating the profile lines of observation stations.