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Date submitted2024-03-22
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Date accepted2024-09-24
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Date published2025-02-25
Behaviour of cerium (III) phosphate in a carbonate-alkaline medium
- Authors:
- Tatyana E. Litvinova
- Stepan A. Gerasev
The article investigates the behaviour of rare earth metals in carbonate-alkaline systems. The results of experimental studies on rare earth element extraction from phosphogypsum, a large-tonnage industrial waste forming in production of phosphoric acid are presented. Using the liquid phase leaching method, it was possible to extract more than 53 % of rare earth elements from old phosphogypsum and more than 69 % from fresh phosphogypsum due to solid phase treatment with a 4 mol/l potassium carbonate solution at temperature 90 °C. The behaviour of model cerium (III) phosphate in a carbonate-alkaline medium is characterized: a solubility isotherm is obtained as well as the dependences of the degree of cerium extraction into solution on temperature, carbonate ion concentration, interphase ratio, stirring intensity, and pH. The ability of soluble rare earth element complexes to precipitate over time was established, which was confirmed using cerium and neodymium as an example. Within 240 h after the end of the experiment, approximately 25 % of cerium and 17 % of neodymium were precipitated from the liquid phase. A similar property was recorded in representatives of the light group and was not noted in elements of the heavy group. The ability to self-precipitate in future can serve as a basis for developing an alternative approach to separating rare earth metals into groups after extraction in a carbonate ion medium. Also, based on the analysis of experimental data, the mechanism of cerium (III) phosphate dissolution in a carbonate-alkaline medium was characterized. An assumption was made that rare earth metal phosphates dissolve sequentially passing into an insoluble carbonate and then into a soluble carbonate complex.
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Date submitted2022-01-28
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Date accepted2022-04-26
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Date published2022-07-26
On the presence of the postmagmatic stage of diamond formation in kimberlites
- Authors:
- Sergey K. Simakov
- Yuri B. Stegnitskiy
On nowadays multiphase and the facies heterogeneity of the formations are distinguished at the study of kimberlite pipes. Most researchers associate the formation of diamonds only with the mantle source. To date, satellite minerals with specific compositions associated with kimberlite diamonds have been identified as deep mantle diamond association. They are extracted from the concentrate of the kimberlites heavy fraction and may reflect the diamond grade of the pipe. For some minerals in the diamond association, however, they can not be reliable. Some researchers also revealed shallow diamond associations, related to the formation of serpentine, calcite, apatite, and phlogopite. There is recent data on the formation of diamonds in rocks of the oceanic crust. In the last years microdiamonds were identified in chromites of the oceanic crust in association with antigorite formed at 350-650 °C and 0.1-1.6 GPa. As a result, the authors established a postmagmatic kimberlitic stage of diamond formation associated with secondary mineral associations based on the experimental and mineralogical data for the conditions of the shallow upper mantle and crust. Mineralogical and petrographic studies of Angolan kimberlite pipe show that antigorite is the indicator mineral of this stage.
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Date submitted2021-04-20
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Date accepted2022-04-26
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Date published2022-07-13
Prediction of the stress-strain state and stability of the front of tunnel face at the intersection of disturbed zones of the soil mass
The article presents a numerical solution of the spatial elastic-plastic problem of determining the stability of the tunnel face soils at the intersection of disturbed zones of the soil mass. The relevance of the study is related to the need to take into account the zones of disturbed soils when assessing the face stability to calculate the parameters of the support. Based on the finite element method implemented in the PLAXIS 3D software package, the construction of a finite element system "soil mass-disturbance-face support" and modeling of the intersection of the disturbed zones of the soil mass were performed. To assess the condition of soils, deformation and strength criteria are taken. The deformation criterion is expressed by the value of the calculated displacement of the tunnel contour in the face, and the strength criterion - by the safety coefficient until the maximum values of the stress state are reached according to the Coulomb–Mohr criterion. The results of the study are presented in the form of histograms of the safety coefficient dependences on the distance to the disturbance at different bending stiffness of the face support structure, as well as the isofields of deformation development. The parameters of rockfall formation in the face zone at the intersection of zones of disturbed soils were determined. The local decrease in strength and deformation properties in the rock mass along the tunnel track should be taken into account when assessing the stability of the tunnel face and calculating the parameters of the support. Within the framework of the constructed closed system, a qualitative agreement of the simulation results with the case of a collapse in the face during the construction of the Vladimirskaya-2 station of the St. Petersburg Metro was obtained.
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Date submitted2020-12-11
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Date accepted2021-03-30
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Date published2021-06-24
Development of new compositions for dust control in the mining and mineral transportation industry
Dust control in summer and winter periods is a topical problem associated with conducting open pit mining operations; however, at negative temperatures the additional requirements are imposed on dust suppressants. Preventive compositions are proposed, in which light and heavy gas oils, obtained from catalytic cracking and delayed coking, are used as base components. Involvement of heavy fractions allows to increase the flash point, thereby reducing the flammability of dust suppressant, improve its adhesion properties by increasing the content of polyaromatic hydrocarbons and reduce the cost of the final product. In order to improve low-temperature and adsorption properties of developed dust suppressants, heavy oil residues (cracking residue and tar) are included in their composition in various concentrations: 2-10 wt.%. Alternative compositions of dust suppressants, obtained by water emulsification of vinylated alkyd oligomer, are developed; the ability of this dispersion to form strong films on dusty surfaces is examined. The efficiency of using aqueous solution of vinylated alkyd oligomer as a summer dust suppressant is demonstrated. The results of this study include the development of new preventive compositions with improved low-temperature properties and confirmation of the theoretical part of the study by the results of performance tests on a laboratory facility.Alternative compositions of dust suppressors have been developed, which were obtained by emulsifying a vinyl alkyd oligomer (VAO) in water; the ability of this dispersion to form strong films on dusty surfaces has been studied. The efficiency of using an aqueous solution of vinyl alkyd oligomer in the summer period as a dust suppressant is shown. The results of this study are the development of new prophylactic formulations with improved low-temperature properties and confirmation of the theoretical part of the study by the results of tests of operational characteristics in a laboratory facility.
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Date submitted2020-10-22
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Date accepted2021-03-02
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Date published2021-04-26
Dynamic simulation of industrial-scale gibbsite crystallization circuit
- Authors:
- Vladimir O. Golubev
- Tatyana E. Litvinova
Population balance model is crucial for improving the method of aluminum hydroxide massive crystallization and enhancing the quality of control over industrial precipitation trains. This paper presents the updated population balance model, which can be used for simulation of industrial-scale precipitation. Processes of birth-and-spread and particle breakage are considered integral parts of the precipitation process along with secondary nucleation, growth and agglomeration of particles. The conceptual difference of the proposed system of equations is its ability to reproduce the oscillatory process that occurs in precipitation circuits as a result of cyclic changes in the quality of the seed surface. It is demonstrated that self-oscillations can occur in the system without any external influence. The updated model is adjusted and verified using historical industrial data. The simulation of seed-recycle precipitation circuit showed an exact correspondence between the calculated dynamic pattern of changes in particle size distribution of aluminum hydroxide and the actual data.
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Date submitted2019-06-22
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Date accepted2019-09-11
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Date published2020-04-24
Effective capacity building by empowerment teaching in the field of occupational safety and health management in mining
The paper is dealing with a developed concept named Empowerment Teaching, which is based on practical teaching experience gained in various mining universities. It is demonstrated that this concept can be used to increase the effectiveness of knowledge transfer to mining countries in the world, as well as to overcome cultural barriers between lecturers and their students. The two models of participatory training, which are proposed to be named “physical” and “emotional” models, are portrayed. The authors are convinced that participatory training methods can be an ideal answer to a challenge associated with workers’ competencies in mining, namely – the potential of highly motivated and well-educated young academics is often diminished by a lack of ability to apply their knowledge. A special emphasis is made on the possible application of empowerment teaching for educational and training activities in the field of occupational safety and health (OSH), which is a matter of utmost importance for the mining industry. Several benchmarking initiatives in the field of OSH (“safety culture”, zero-accident vision) are underlined to be encouraged and promoted by means of new teaching methods. The examples of successful international cooperation among universities are given, as well.
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Date submitted2019-03-05
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Date accepted2019-05-03
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Date published2019-08-23
Efficiency Estimation of the Single- and Multicomponent Anti-hydrate Reagents
- Authors:
- N. A. Shostak
- E. P. Zaporozhets
Different types of technological and technical problems in the oil, gas and chemical industries are connected with the hydrate formation process and with the using of anti-hydrate chemicals. That is why, it is necessary to estimate thermobaric ranges within which reagents does not let hydrate to grow or is their dissociation. Also, to estimate anti-hydrate influence we need to determine the chemicals’ anti-hydrate efficiency and chose the best one. They make the reagents consisting of several chemical components depending on the purpose of their application – for prevention of formation and (or) elimination of hydrates. It demands calculations of the optimum concentration and expenses and also the intensity (speed) of hydrates dissociation causing with the reagents. The analytical method of the anti-hydrate chemical reagents efficiency determination containing one or several components from different classes of chemical compounds – alcohols, salts, acids, compounds of nitrogen and oxygen – is presented in this paper. With its help it is possible to define decrease in temperature of hydrate formation from reagents influence, to count key parameters of reagents anti-hydrate efficiency depending on component compositions of hydrate gas and a phase condition of a hydrate-gas system, to select types of chemical components and their quantity in multicomponent reagents, i.e., to make new compounds. The method can be used for express assessment of anti-hydrate chemical reagents efficiency on criteria sign for practical application in oil, gas and processing industry.
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Date submitted2017-08-26
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Date accepted2017-11-10
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Date published2018-02-22
On enhancement of cooperation between universities for implementation of the program «Sustainable development–2030»
- Authors:
- P. Ochirbat
- B. Chinzorig
The article is focused on one of the pressing issues of our time – the international training of qualified personnel in higher education institutions with the aim of developing a stable economic system of the state, the main elements of which are interrelated stages of economic activity (exploration, prospecting, extraction, processing, and use of mineral resources). The question of the contribution and role of universities of different countries cooperating in the sphere of sustainable development of this sector is considered. The necessity of practical solution of this task for the implementation of UNESCO's program «Sustainable Development – 2030» is determined. In this relation, the concept of «sustainable development», its philosophical, scientific-theoretical and cultural aspects are considered, the special significance of the connection between the sustainable development of society and its individual fragments with modern education is emphasized. It is stated that education, in the context of sustainable development, should be anticipating, advancing and open. Given the current trends in higher education, it is possible to mention the work carried out by the Mining Institute of the Mongolian State University of Science and Technology in the direction of international cooperation.
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Date submitted2016-11-07
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Date accepted2016-12-27
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Date published2017-04-14
Method of determining characteristics for air heating system in railway tunnels in harsh climatic conditions
- Authors:
- S. G. Gendler
- S. V. Sinyavina
The article describes climatic and mining-technical conditions influencing frost formation process. It was noted that the radical tools for preventing frost formation in winter periods is creation of positive temperature in tunnels by heating the incoming outside air. We formulated tasks, which solution will promote development of engineering calculation method for heating systems parameters. The article provides results of theoretical studies based on mathematical modelling and analytical solutions and data on field instrumental measurements, which were processed with similarity criteria. It compares mathematical modelling results on determining amount of tunnel incoming air flow with portal gates and calculations data from experimentally determined coefficient of local resistance. We proved the energy efficiency of placing the tunnel portal gates and validated the places of preheated air injection points and removal of cool air from this flow, which provides maximal energy effect.
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Date submitted2015-12-01
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Date accepted2016-02-29
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Date published2016-12-23
Simulation of diesel engine energy conversion processes
- Authors:
- A. S. Afanasev
- A. A. Tretyakov
In order to keep diesel engines in good working order the troubleshooting methods shall be improved. For their further improvement by parameters of associated processes a need has arisen to develop a diesel engine troubleshooting method based on time parameters of operating cycle. For such method to be developed a computational experiment involving simulation of diesel engine energy conversion processes has been carried out. The simulation was based on the basic mathematical model of reciprocating internal combustion engines, representing a closed system of equations and relationships. The said model has been supplemented with the engine torque dynamics taking into account the current values of in-cylinder processes with different amounts of fuel injected, including zero feed. The torque values obtained by the in-cylinder pressure conversion does not account for mechanical losses, which is why the base simulation program has been supplemented with calculations for the friction and pumping forces. In order to determine the indicator diagram of idle cylinder a transition to zero fuel feed mode and exclusion of the combustion process from calculation have been provisioned.
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Date submitted2015-10-11
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Date accepted2015-12-13
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Date published2016-08-22
The specifics of operating minor deposits (as given by the examples of gas condensate deposits of the Northern Caucasus)
- Authors:
- R. A. Gasumov
One of the most important directions in upgrading well productivity in the process of mining hydrocarbons consists in fighting with salt formation and salt deposition. Solving that problem becomes especially actual when operating deposits that are in their final stage of exploitation in complex mining and geological conditions accompanied by deposition of salts in the well foot area of oil bed and their sedimentation on the sub-surface and surface equipment. It provokes a drop in well productivity and results in off-schedule repair works. Specifics are considered of exploiting minor gas condensate deposits of the Northern Caucasus that are operated under complicated mining and geological conditions of anomalously high bed pressures, high temperatures, strong depressions on the beds and inflow of mineralized water from water saturated seams. Processes are studied of salt deposition from heavy hydrocarbons in the well foot and the bed area surrounding it. Water sample analyses data from different wells have demonstrated that the main salts carrier is the associated water, and the principal sedimenting agents are corrosion products, as confirmed by the results of microscopic studies. The dynamics is presented of salt deposition in the “well foot – wellhead – separator” system retrieved from the results of studies of reaction products in the well foot zone of oil bed. It is demonstrated that the efficiency of struggling with salt deposition in the course of mining hydrocarbons depends on comprehensive approach to the problem, the principal thrust lying with prevention of such deposition. Possible ways are considered to prevent precipitation of ferric compounds in the course of operating gas condensate wells, a way is suggested to intensify gas inflow.
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Date submitted2014-11-08
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Date accepted2015-01-27
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Date published2015-10-26
Geochemistry of ore-forming hydrothermal fluids of the World ocean
- Authors:
- C. M. Sudarikov
- M. V. Zmievskii
The most complete results of the study of hydrothermal ore-forming solutions geochemistry in the Russian and international expeditions to deep-sea hydrothermal fields of the world ocean are analyzed. Solutions of both high and low salinity with respect to seawater are formed in the discharge zone of fluids. Positive correlation of ore components with the chloride ion and negative one with the pH value may indicate the migration of components in acidic hydrothermal solutions in the form of chloride complexes. Hydrogen sulfide is associated with the significant positive correlation with metals, which indicates reducing conditions forming in ore-bearing hydrothermal solutions. This is confirmed by the close relationship of ore components with hydrogen. The transfer of metals mainly in the form of chloride complexes at high temperatures of the solution is confirmed by the results of our thermodynamic modeling. Methane is characterized by negative dependence on temperature and concentration of ore components, associated with positive dependence on pH and negative one on hydrogen sulfide. Each of the observed dependencies can testify against abiotic theory of income of methane in hydrothermal solutions. The following geochemical indicators are the most promising for the discovery of new ore deposits and the organization of geochemical monitoring during the development of already discovered fields: Eh, pH, Cl, Fe, Mn, H 2 S, CO 2 , H 2 and possibly CH 4 .
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Date submitted2014-06-23
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Date accepted2014-08-27
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Date published2014-12-22
Theoretical aspects of the kinetics of gas hydrates
- Authors:
- E. P. Zaporozhets
- N. A. Shostak
In the systems of collection, preparation, transportation and processing of hydrocarbons in conditions of a certain temperature and pressure, gas hydrates, which adversely affect the operation of the processing equipment, are formed. To prevent hydrate formation, it is necessary to determine the time and rate of growth. For this purpose, physical and mathematical models describing the growth of crystalline hydrates are being designed and developed. The developed models differ from one other. The reason for the difference is that each model is designed for specific temperature and pressure conditions and individual gas hydrates (or mixtures). The main theoretical models describing the process of growth of hydrates under different conditions are presented.
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Date submitted2013-07-09
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Date accepted2013-09-04
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Date published2014-03-17
A new chemical method of dust suppression for the storage of the rock mass
The using of chemically-active reagents is one of the most promising directions in the process of dust suppression. Due to the need to develop new ways of suppression of dust during storage of the rock mass. The paper provides the analysis of the use of calcium carbide as an element of the dust suppression system and the system of permafrost rocks.
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Date submitted2009-10-29
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Date accepted2009-12-26
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Date published2010-09-22
Control system of rock pressure at the «Antey» deposit
- Authors:
- B. A. Prosekin
- E. A. Ilin
The paper deals with the geomechanical monitoring system of the Antey deposits of uranium ores. Characteristics of the methods and means for rock pressure control are given.
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Date submitted2009-09-14
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Date accepted2009-11-28
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Date published2010-06-25
Formаtion of a new type individuality under the conditions of generation of integration of interdependent communities
- Authors:
- A. I. Mikheev
This paper deals with the question of model generation of a new type individuality, that contemporary society demands for an advanced, deteriorative-free, balanced and creative development, which renders possible the elaboration of a system of formation of the given linguistic identity as a result of foreign language teaching.
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Date submitted2009-09-14
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Date accepted2009-11-30
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Date published2010-06-25
Humanitarization of the ecological education аs a function of the ecological expert training system
- Authors:
- I. G. Rebeshchenkova
Ecological crisis is the essential part of the total crisis of the modern civilization. It is the consequence of the number of the causes, including dehumanization of society, moral decadence, loss of need in the beauty and so on. These processes are the special danger for the young generation. For the neutralization of the negative processes it is necessary to combine the ecological education with the ecological training, is engaged in its humanitarisation. In this connection we have the task of the creation of the ecological preparation system of the specialists. Saint Petersburg State Mining Institute is the first institute in Russia, in which are introduced the disciplines of the ecological profile and in which is accumulated the considerable experiment in the education of the engineers-ecologists, is created the scientific base and the skilled workers, is extended the spectrum of the directions and the disciplines – is laid of the stable foundation for the proposed system of the ecological education. The natural-science and engineering blocks of this foundation with the necessity must are cemented with the block of the social and humanistic disciplines, including ecoethics, ecoesthetics, ecopsychology, ecophilosophy, ecohistory, ecopolitology, ecoethnology, etc.
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Date submitted2009-07-02
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Date accepted2009-09-11
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Date published2010-04-22
Application of solid oxygen-containing substances for higher productivity of oil wells
- Authors:
- A. T. Karmansky
- E. V. Goncharov
The technological principles and results of realization of exothermal reactions in oil-and-gas productive wells are presented. Unique comfinations of chemical reagents on base of chlorates, saltpetres, etc ensured the simplicity, low prices and efficiency of technological operations for intensive influxes of oil and gas. High efficiency is reached not only due to reduction of oil viscosity and removal of paraffin and asphaltenes, but also due to re-forming of the reservoir rocks by relief of rock pressure and extension of fractures.
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Date submitted2009-07-17
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Date accepted2009-09-18
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Date published2010-04-22
Transformation of the form and angular parameters of rock movement processes with depth at ore deposits
- Authors:
- A. G. Shadrin
- M. A. Shadrin
It was established the increase of movement angles with mining depth and the mechanism of forming the stable natural arching in underground mining of ore deposits. The conditions and parameters of forming the stable natural arching were determined, under which the zone of dangerous deformations localizes inside the ore mass and does not manifest itself on the earth surface. The nomogram for analytical determination of the rock movement angles was developed, and the table was drawn up of the natural arching conditions with due account of main mining-and-geological factors of ore deposit occurrence and its mining.
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Date submitted1958-03-03
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Date accepted1958-05-17
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Date published1958-05-09
ПРЕДПОСЫЛКИ УГЛЕОБРАЗОВАНИЯ
- Authors:
- Unknown
Вопрос о предпосылках углеобразования нуждается в периодическом пересмотре вследствие непрерывного прогресса в различных областях геологической науки и критической проверки многих ее положений на основе диалектического мировоззрения и исторического сопоставления. Многое в угольной геологии, что было постоянным и застывшим в положениях западно-европейских руководств и казалось незыблемым и, что было выведено из изучения среднекарбоновых каменных углей на практике оказалось неполным, односторонним и неправильным в приложении к угленакоплению более молодых угленосных эпох. При рассмотрении всего многообразия угольных бассейнов различного возраста бросается в глаза прежде всего непостоянство обстановки, благоприятствующей угленакоплению из периода в период. Представление об одних каких-то стандартных оптимальных условиях и необходимых предпосылках углеобразования должно быть отброшено и заменено представлением о необратимом развитии этих предпосылок во времени и пространстве.