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Date submitted2023-10-28
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Date accepted2024-11-07
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Date published2025-02-25
Radiation characteristics of coals at different stages of metamorphism
The formation of deposits and subsequent metamorphic processes that affect concentrations of radioactive elements in coal can indicate ongoing geological activities, therefore, analyzing trends in the radiation characteristics of coal throughout the metamorphic series is highly relevant. The aim of this work is to experimentally evaluate the radiation characteristics of different coal ranks (metamorphic stages) using thermoluminescent (TL) dosimetry and beta activity measurements, and to identify correlations between these radiation characteristics and data obtained from technical, elemental, and thermogravimetric analyses, as well as mass spectrometric and electron paramagnetic resonance spectroscopy (EPR) measurements. For dosimetric measurements that indirectly characterize the content of radionuclides in coal, a modified dosimetric complex and original soil-equivalent thermoluminescent detectors based on SiO2 were used. The analysis of the obtained results supports the use of TL studies to determine the ash content of coals at low and medium stages of metamorphism (coal rank B→G), while indicating that this method is not feasible for coals at higher stages of metamorphism. The correlation dependencies in the metamorphism series suggest abrupt change in the conditions of coal formation during the time range corresponding to transformation from high to low volatile bituminous coals (coal rank G→Zh→K). These abrupt changes in regional metamorphism conditions (time, temperature, pressure, oxidation-reduction conditions) are confined to the boundary of the Permian and Triassic periods (~250 million years ago), during which both the transformation of existing coal deposits and the formation of new deposits occurred.
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Date submitted2024-05-08
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Date accepted2024-11-07
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Date published2024-12-12
The effect of mechanical and thermal treatment on the characteristics of saponite-containing material
Solving the problems of modern building materials science is reduced to obtaining high-quality materials, expanding and searching for a rational raw material base, which can be carried out through the use of various industrial wastes. In this paper, the possibility of using waste from the mining industry – saponite-containing material (SCM) obtained during the enrichment of kimberlite ores from the Lomonosov diamond deposit, as an active mineral additive for cement binders and concretes is considered. The influence of mechanical and thermal treatment on a number of properties of the material selected from the tailings dump and in its initial state was studied. The study of the surface activity of SCM samples consisted in determining the sorption capacity, acid-base centers and their distribution. An increase in the activity of the surface of the material particles as a result of mechanical activation and its decrease during temperature treatment were determined. These effects are associated with phase rearrangements and structural changes in the sandy-clay rock, which was confirmed during thermal analysis. The temperature effect has no pronounced effect on the microstructure, the “smoothness” of the particles and the formation of a consolidated surface of the structural elements of the saponite-containing material are noted.
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Date submitted2022-05-17
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Date accepted2023-04-03
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Date published2024-02-29
Improvement of concentrate quality in flotation of low-rank coal
- Authors:
- Sergei A. Kondratev
- Tatyana A. Khamzina
Percentage of high-rank coal with low content of ash, moisture, and sulfur in total coal production output is low. Most of the produced coal has a low quality (lignite, bituminous coal: long-flame and fiery). Under increasing requirements for ecological cleanness of coal, the efficient use of coal products is only possible after improvement of their processing properties. The authors discuss the enhancement of flotation efficiency of low-rank coal using the mechanism of physisorption of a collecting agent in particle – bubble attachment. It is explained why the yield of concentrate with low ash content increases as a result of combination of collectors having different physical properties. It is shown that the surface activity of a heteropolar agent relative to the gas – liquid interface and the adsorption density of the agent govern its collecting properties. Based on the recovery – surface activity relationship, the correlation is found between the collecting activity of a chemical compound and the structure of its molecules. The combination of the collectors with different surface activity enables adjusting collectability and selectivity of the blend. The physisorption mechanism of collectors can be a framework for developing recommendations on modification of concentrate yield and ash content, and on selection of optimized ratios of surface activities of miscible collectors relative to the gas – liquid interface.
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Date submitted2022-10-24
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Date accepted2023-03-03
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Date published2023-04-25
Use of clay-containing waste as pozzolanic additives
Growing productivity of mining and processing enterprises entails an increase in the volumes of liquid tailings impoundments and upstream impoundments of ore processing waste. Enterprises face the challenge of minimizing the environmental impact of waste and guaranteeing the sanitary and epidemiological safety of population. The article presents a possibility of recycling one type of such waste (clay-containing concentration tailings of apatite-nepheline and sylvinite ores, coal beneficiation tailings) by using them after preliminary thermochemical treatment as pozzolanic additives to cements and concretes, including concrete mixtures used for soil stabilization, development of territories, reclamation of mine workings, as a component of the insulating layer of landfills for the disposal of municipal solid waste. An analysis of the phase changes of kaolinite, one of the main minerals that make up clay-containing waste, in the temperature range of 200-1,000 °С showed that a change in its mineral form during heat treatment is the main factor in changing its pozzolanic activity. The effect of heat treatment of clay minerals at temperature of 700-800 °C on their pozzolanic activity, estimated by the ability to absorb calcium hydroxide (0.7 g Ca(OH) 2 per 1 g of modified kaolinite), is considered. It is shown that the addition of heat-treated samples (20 % by weight) improves the quality of cement increasing its activity by 15 %, in comparison with the use of unmodified clay minerals. It was proved experimentally that partial replacement of Portland cement with thermally modified kaolinite increases the strength of consolidating stowing mixture by up to 15 %. This approach to processing of ores containing layered silicates, which provides for thermochemical modification of run-of-mine ore, intensifies the processes of tailings thickening and filtering.
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Date submitted2022-03-17
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Date accepted2022-06-20
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Date published2022-11-03
Assessment of collecting activity of physically sorbed reagents on the example of easily floatable coking coal sludge
- Authors:
- Sergey A. Kondratev
- Tatyana A. Khamzina
The article presents one of the new approaches to theoretical assessment of collecting ability of reagents. The efficiency of reagents-collectors with different chemical composition used for flotation of coking coals was studied. A comparative assessment of the flotation activity of kerosene, mineral oil, thermal gas oil, KETGOL and FLOTEK is given. The criteria of collecting activity of the above reagents-collectors for coal sludge flotation were specified. A correlation was established between the indicators of coal sludge flotation by the above reagents and their physical parameters. It is shown that the rate of spreading over water surface can characterize the flotation activity of reagents. Based on dependence of the collecting activity of a reagent on its rate of spreading along the “gas – liquid” interface and surface pressure, the main approaches to determining the structure and composition of molecules of an effective flotation collector can be determined. A new concept of the function performed by a physically sorbed collector in the elementary act of flotation and a criterion for the flotation activity of reagents used in coal sludge beneficiation are proposed. It is shown that the collector used in coal flotation, in addition to hydrophobizing the surface of the extracted particles, should reduce the induction time and remove the kinetic constraint on formation of a flotation aggregate.
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Date submitted2018-09-07
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Date accepted2018-11-08
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Date published2019-02-22
Assessment of refractory gold-bearing ores based on interpretation of thermal analysis data
- Authors:
- T. N. Aleksandrova
- G. Heide
- A. V. Afanasova
The article presents the results of a study on the possibility to assess refractory gold-bearing ores using thermal analysis data. It studies the flotation concentrates obtained during the enrichment of double refractory sulfide gold-bearing ores. This type of ore is complicated by the fine impregnation of gold in sulphide minerals and the presence of sorption-active scattered carbonaceous matter, which is in close association with sulphides. The results of thermogravimetric and mass spectrometric studies of refractory gold-bearing ores are presented. The obtained fragments for kerogen CH (m/z = 15), C 2 H (m/z = 29) and C 3 H (m/z = 43) indicate the presence of various types of carbonaceous matter in the studied samples. It is justified that the degree of sorption activity of carbonaceous matter depends on the presence of kerogen and bitumen in the ore. High sorption activity of scattered carbonaceous material significantly affects the processing technology of ores and concentrates, both flotation and pyro- and hydrometallurgical methods. Thermogravimetric and mass spectroscopic analyzes can be used to determine the degree of preg-robbing of refractory gold-bearing ores. The obtained results predetermine the direction of creating new methods and technologies in the field of decarburization of refractory gold-bearing ores in the integrated development of solid minerals in the mining regions of Russia.
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Date submitted2018-09-10
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Date accepted2018-11-06
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Date published2019-02-22
Comparative analysis of zincand tin oxidation with acids at room temperatures
- Authors:
- S. D. Pozhidaeva
- L. S. Ageeva
- A. M. Ivanov
The paper analyses the parameters of deep oxidation of zinc and tin by copper (II) compounds and molecular iodine in the presence of molecular oxygen and hydrogen peroxide, as second oxidizers working synchronously with them in various media (aqueous, aqueous-organic and organic) with the participation of mineral and carboxylic acids close to room temperature. The contribution of the reactivity of the metal to its rate of consumption, especially the average, is often much less than the contribution associated with the release characteristics of the working surface, determined by the rates of accumulation of surface deposits of metal oxidation products, their strength and adhesion characteristics their destruction and shifting into the bulk phase.
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Date submitted2014-12-07
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Date accepted2015-02-23
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Date published2015-12-25
Bump hazard evaluation of a rock mass area as a result of its seismic acoustic activity registration
- Authors:
- V. V. Nosov
Ore production in deep rock-bump hazardous mines is closely connected with the need to in-crease workers’ safety, which demands heavy costs of taking preventive shockproof actions and applying expensive protection systems against mountain blows. The article considers a resource forecasting technique and a bump hazard evaluation method for a rock mass area, based on a mi-cromechanical model, which registers acoustic emission of heterogeneous materials, and empirical data, obtained as a result of acoustic signals registration with the help of the model, aimed at seis-mic-acoustic activity evaluation at «Taimir» and «Oktyabrsky» rock mass areas, belonging to Norylsk industrial region.
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Date submitted2009-10-12
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Date accepted2009-12-26
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Date published2010-09-22
Methods and techniques for control of rockburst-hazard in underground mining at ore mines of the Far-East district
An assessment is given to the present-day state of control of dynamic rock pressure manifestations in the rockburst-hazardous ore mines of the Far-East district. Consideration is given to the used methods and facilities for control of rock pressure and the ways for their improvement . Basic foundations of methodical approaches to the assessment of geomechanical state of rock mass by data of geoacoustic control are considered.
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Date submitted2009-10-22
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Date accepted2009-12-27
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Date published2010-09-22
Preconditions for prediction of technogenic seismic activity by cycles of objects of the solar system
- Authors:
- B. G. Tarasov
- A. G. Olovianny
- L. V. Bugaenko
The paper contains the statistical rows of rockbursts, sudden outbursts of methane at coal mines and ore mines in Russia for the period from 1954 to 2007, as well as the reflection in them of the eleven-year cycles of the Sun activity. Some results are presented of computer modeling of activation periods of outburst-hazardous state of rock mass at coal mines of the Kuzbass basin. Recommendations are given.
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Date submitted2009-10-14
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Date accepted2009-12-11
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Date published2010-09-22
Investigation of present-day stress-strain state of rock mass by the results of observations at geodynamic polygons
- Authors:
- S. N. Savchenko
- E. V. Kasparyan
- Yu. G. Smagina
The methods are suggested for treatment of the results of optical distance and levelling measurements at the underground geodynamic polygons involving in their calculation the tensors of additional stresses and deformations, component of rotation and specific energy of deformability. As an example, consideration is given to changes in time of movements, deformations and specific energy of deformability at one of geodynamic polygons of the Kola peninsular.
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Date submitted2009-10-26
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Date accepted2009-12-27
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Date published2010-09-22
Support of geodynamic safety in mining of the Khibini deposits
The paper deals with the problems of geodynamics in mining of the Khibini deposits. Description is given to the complex of organizational-technical arrangements for provision of geodynamic safety at the Apatit Co and to principal trends of its development.
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Date submitted2009-10-01
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Date accepted2009-12-02
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Date published2010-09-22
Specific manifestations of tectonic and seismic activity in Kuzbass
- Authors:
- A. I. Ekimov
- S. V. Tsirel
The conducted observations demonstrated the substantial growth and variation of nature of tectonic and seismic activity in Kuzbas. Growth of geodynamic risks is marked. Methods for study of observable processes are suggested.
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Date submitted2009-10-17
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Date accepted2009-12-07
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Date published2010-09-22
Regularities of progressing of technogenic seismic activity in mining areas
- Authors:
- S. V. Tsirel
Regularities of variation of cumulative graphs of seismic events repetition in process of transferring from natural seismic activity to the technogenic one are studied. Processes of growth of technogenic seismicity in mining regions on examples of the Kola peninsula and Kuzbass are reviewed.
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Date submitted2009-09-10
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Date accepted2009-11-11
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Date published2010-06-25
Stages of training activation methods development
- Authors:
- M. A. Perfilova
The article is dedicated to the problem of developing methods of training activation. Historical and pedagogical background for the development of these methods and distinguishes the stages of training activation methods development from the ancient times till nowadays are analysed. The brief chronological survey is presented tabular. The main features of the methods of active training are pointed out.
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Date submitted2009-09-25
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Date accepted2009-11-18
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Date published2010-06-25
Methodic aspects of development of students` creative abilities in humanity courses in technical universities
- Authors:
- O. E. Bespalova
- O. N. Bondareva
The article deals with methodic aspects of development of students` creative abilities in humanity courses in technical universities. The complementary studies promoting creative self-realization of student’s person in art and culture spheres are presented.
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Date submitted2009-09-10
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Date accepted2009-11-15
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Date published2010-06-25
Media text substance and culturally significant information extraction
- Authors:
- K. P. Sidorenko
The article deals with interpretation of quotation (intertextual substance) in modern Russian speech and forming didactic principles in innovations aspect. Some practical materials concerning culturally significant information extraction are given.
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Date submitted2009-09-08
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Date accepted2009-11-12
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Date published2010-06-25
Psychology of creativity
- Authors:
- L. Ya. Zobnina
Article is devoted to problems of psychology of creativity. The author considers approaches of various authors to understanding of mechanisms of creative activity. It is offered to differentiate at an explanation of creative decisions two forms unconscious: sub consciousness and above consciousness.
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Date submitted2009-09-19
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Date accepted2009-11-15
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Date published2010-06-25
Potassium chloride content in ore and products оf recycling automatic control system
- Authors:
- S. S. Galushkin
- B. A. Vishnyak
- V. N. Smirnov
Potassium chloride percentage in continuous transported ore flows and products of potassium plants recycling automatic control system is offered and described. It differs fundamentally from used before ones at bulk solids containing natural radio-activity elements effective constituents producing and recycling plants. Sensing device is used in this information-measuring system (IMS). It allows to realize automatic control in flows for that instantaneous productivity fluidity in wide limits is resided. Using such IMS gives considerable economic effect by measurements error lowering and their quickness increase.
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Date submitted2008-11-17
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Date accepted2009-01-28
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Date published2009-12-11
Rating indicators of the financial condition estimation of mining enterprise
- Authors:
- J. V. Luebeck
The method of receiving of united factor is considered to be the foundation of system development monitoring factors based on integrations of private factors of financial analysis, that is to say calculation of rating for different variants of investment activity a mining enterprise. Calculation of rating of borrower and rating of financial stability has the most importance while developing the investment strategy of development a mining enterprise. Rating analysis will allow to motivate the possibility for calculating the real investments, defining the value of rational growth of production volumes, motivating the borders of rational increase the volumes of production within the framework of investment activity.