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Date submitted2023-07-31
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Date accepted2024-11-07
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Date published2025-02-25
Environmental assessment of biochar application for remediation of oil-contaminated soils under various economic uses
- Authors:
- Tatiana V. Minnikova
- Sergey I. Kolesnikov
Remediation is an important area of oil-contaminated soil restoration in Russia, since oil refining industry is the major one for Russia and neighbouring countries, and the issues of environmentally effective and economically profitable remediation of oil contamination have not yet been solved. Soils under various economic uses have different surface areas and degrees of soil particles envelopment with oil due to the presence or absence of cultivation, the amount of precipitation and plant litter. The introduction of various substances for remediation into oil-contaminated soils of steppes (arable land), forests, and semi-deserts, considering their differences, gives different results. Biochar is coal obtained by pyrolysis at high temperatures and in the absence of oxygen. The uniqueness of this coal lies in the combination of biostimulating and adsorbing properties. The purpose of the study is to conduct an environmental assessment of biochar application for remediation of oil-contaminated soils under various economic uses. The article compares the environmental assessments of biochar application in oil-contaminated soils with different particle size fraction. The following indicators of soil bioactivity were determined: enzymes, indicators of initial growth and development intensity of radish, microbiological indicators. We found that the most informative bioindicator correlating with residual oil content is the total bacteria count, and the most sensitive ones are the roots length (ordinary chernozem and brown forest soil) and the shoots length (brown semi-desert soil). The use of biochar on arable land and in forest soil (ordinary chernozem and brown forest soil) is less environmentally efficient than in semi-desert soil (brown semi-desert soil). The study results can serve to develop measures and managerial and technical solutions for remediation of oil-contaminated soils under various economic uses.
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Date submitted2024-03-18
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Date accepted2024-11-07
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Date published2025-01-14
Public-private partnership in the mineral resources sector of Russia: how to implement the classical model?
A comparative financial and economic analysis is conducted of different public-private partnership (PPP) models for industrial infrastructure construction projects in an underdeveloped resource-rich region. The Stackelberg game theory-based model is used to build a parametrized family of bilevel mathematical programming models that describe an entire spectrum of partnership schemes. This approach enables a comparison of different strategies for the distribution of infrastructure investments between the government and the subsoil user and hence a scenario of transformation of Russia’s current PPP scheme into the classical partnership model, which is practiced in developed economies. To this end, a database is created on fifty polymetallic deposits in Transbaikalia, and a comparative analysis is conducted of Stackelberg-equilibrium development programs that implement different PPP models. The numerical experiment results show the classical PPP model to be most effective in the case of a budget deficit. The analysis helps assess the economic consequences of a gradual transformation of the partnership institution in industrial infrastructure construction from investor support in the Russian model to government support in the classical scheme. Intermediate partnership models, which act as a transitional institution, help reduce the budget burden. These models can be implemented by clustering the deposits, developing subsoil user consortia, and practicing shared construction of necessary transport and energy infrastructure. The intensification of horizontal connections between subsoil users creates favorable conditions for additional effects from the consolidation of resources and can serve as a foundation for a practical partnership scheme within the framework of the classical model.
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Date submitted2023-07-27
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Date accepted2024-06-03
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Date published2024-12-25
Normalized impulse response testing in underground constructions monitoring
Impulse Response testing is a widespread geophysical technique of monolithic plate-like structures (foundation slabs, tunnel lining, and supports for vertical, inclined and horizontal mine shafts, retaining walls) contact state and grouting quality evaluation. Novel approach to data processing based on normalized response attributes analysis is presented. It is proposed to use the energy of the normalized signal calculated in the time domain and the normalized spectrum area and the average-weighted frequency calculated in the frequency domain as informative parameters of the signal. The proposed technique allows users a rapid and robust evaluation of underground structure’s grouting or contact state quality. The advantage of this approach is the possibility of using geophysical equipment designed for low strain impact testing of piles length and integrity to collect data. Experimental study has been carried out on the application of the technique in examining a tunnel lining physical model with a known position of the loose contact area. As examples of the application of the methodology, the results of the several monolitic structures of operating municipal and transport infrastructure underground structures survey are presented. The applicability of the technique for examining the grouting of the tunnel lining and the control of injection under the foundation slabs is confirmed. For data interpretation the modified three-sigma criteria and the joint analysis of the attribute’s behavior were successfully used. The features of the field work methodology, data collection and analysis are discussed in detail. Approaches to the techniques' development and its application in the framework of underground constructions monitoring are outlined. The issues arising during acoustic examination of reinforced concrete plate-like structures are outlined.
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Date submitted2024-03-28
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Date accepted2024-06-03
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Date published2024-07-04
Assessing the effectiveness of sewage sludge in the reclamation of disturbed areas in the Kola subarctic zone (a case study of a sand quarry)
An assessment was made of the effectiveness of reclamation using sewage sludge for the accelerated formation of a stable erosion-proof vegetation cover on the unproductive anthropogenic soil of a sand quarry in the context of the Kola North. The experiment, launched in 2017, included three treatments: control – no treatment, experiment 1 – fragmentary (50 %) application of sewage sludge, experiment 2 – continuous application. In the sixth growing season, anthropogenic soil samples were examined, and measurements of CO2 emissions were carried out. It was shown that the application of sewage sludge had a positive effect on the physicochemical and agrochemical properties of the soils: in situ pH and density decreased, hygroscopicity increased, available phosphorus and potassium increased. Significant differences (p < 0.05) were found between CO2 emissions in the control and experimental treatments. The content of organic carbon in the control treatment was lower than in the experimental ones; under fragmentary application of sewage sludge, it was three times lower, and under continuous application, it was nine times lower. Significant (p < 0.05) differences in the content of carbon and nitrogen in cold and hot water extracts between control and treatment samples were found under continuous application of sewage sludge. At the same time, by calculating the C/N ratio, a very low level of nitrogen was found in the humus. The main factors behind the variability of the estimated parameters were identified – the treatment itself and the method of its application, the contribution of the treatment alone was 60 %, the contribution of the application method was 14 %. Taking into account the economic factors, fragmentary application of sewage sludge onto the anthropogenic sand quarry soil is recommended to support the establishment of a stable erosion-proof phytocenosis.
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Date submitted2024-04-22
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Date accepted2024-06-13
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Date published2024-07-04
Comprehensive utilization of urban wastewater sludge with production of technogenic soil
The article presents the analysis of the existing approach to wastewater sludge treatment and justifies the selection of the most promising management technology that allows maximum use of wastewater sludge resource po-tential. To obtain a useful product (biocompost) suitable for use as part of technogenic soil, experimental studies of aerobic stabilization of organic matter of dehydrated urban wastewater sludge with the addition of other waste by using passive composting technology were carried out. The technology is included in the list of best available technologies (BAT). The selection of the most optimal components for the mixture was based on the results of determining the C and N content, humidity and pH of the components used that ensured the composting of organic waste. The results of laboratory studies of the obtained biocompost according to the main agrochemical and sanitary-epidemiological indicators are presented. Testing was carried out according to the criterion of toxicity of the biocompost’s aqueous extract. The assessment of the technogenic soil was performed when using biocompost in its composition for compliance with existing hygienic requirements for soil quality in the Russian Federation. Based on the results of the vegetation experiment, optimal formulations of the technogenic soil were determined, i.e., the ratio of biocompost and sand, under which the most favorable conditions for plant growth are observed according to a combination of factors such as the number of germinated seeds, the maximum height of plants and the amount of biomass. The conducted research makes it possible to increase the proportion of recycled urban wastewater sludge in the future to obtain soils characterized by a high degree of nutrient availability for plants and potentially suitable for use in landscaping, the biological stage of reclamation of technogenically disturbed lands, as well as for growing herbaceous plants in open and protected soil.
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Date submitted2024-03-29
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Date accepted2024-06-03
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Date published2024-07-04
Potential use of water treatment sludge for the reclamation of small-capacity sludge collectors
- Authors:
- Olga M. Guman
- Irina A. Antonova
In small settlements, collectors for the sludge produced during water treatment processes are small-sized and located in the vicinity of drinking water storage reservoirs or in coastal areas. Sludge removal is not economical. Besides, the relief depressions formed after sludge disposal are required to be reclaimed. In ore mining regions, where the main settlements of the Urals are located, sludge produced in water treatment has high contents of heavy metals typical of ore mining provinces. Consequently, places of sludge accumulation are potential sources of water pollution. The article discusses the possibility to mix sludge with slaked lime and local overburden with the help of special equipment. So far water treatment sludge in the region has been used to reclaim the surface of solid waste landfills by creating anaerobic conditions for waste decomposition. When placed inside the embankment dams as an independent object, sludge needs to be improved for the increase of its bearing capacity and the ability to bind heavy metals. The article aims at the substantiation of the composition and properties of the reclamation material made of the water treatment sludge mixed with local overburden and slaked lime (technosoil). For this reason the paper describes the composition of the sludge in a sludge collector, the composition and properties of the overburden rocks as a component of the mixtures with water treatment sludge, the composition and properties of the mixtures of water treatment sludge with overburden rocks and Ca(OH)2 as a component dewatering sludge and neutralizing toxicants. Furthermore, the research work provides the technology created for the optimal processing of the water treatment sludge in the process of the reclamation of a sludge collector. The research results and the experience obtained in reclamation of disturbed lands in the region have confirmed the possible use of technosoil for the reclamation of small-capacity sludge collectors. The analysis of the chemical composition and physical and mechanical properties of the mixtures under study has shown that the most economical and environmentally sound reclamation material is a mixture of water treatment sludge, loose overburden dump soils and Ca(OH)2 in a ratio of 60 : 30 : 10 %.
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Date submitted2023-08-02
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Date accepted2023-12-27
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Date published2024-04-25
Justification of the approaches to improve management strategy of the mining system based on the analysis of data on the mining of complex structural rock blocks
Long-term activity of mining enterprises causes the necessity to substantiate the strategies of management of the mining and technical system functioning in terms of improvement of ore quality control, which is determined by its change in the course of field development due to the priority development of the main reserves and, as a consequence, forced transition to the mining of complex structural rock blocks with a decrease in the recovery percentage, which is typical in case the ore component meets the requirements of the feasibility study in terms of grade at substandard capacity. In this case, it is possible to identify the recovery percentage and the potential for its increase by analyzing the long-term activity of the mining and industrial enterprise, namely, by analyzing the data of mining complex structural rock blocks with the subsequent establishment of the relationship between the primary data on mining and geological conditions and information on the quality of the mineral obtained from the technological equipment. Therefore, the purpose of the research was to substantiate the necessity of improving the management strategy of the mining-technical system functioning, which consists in the fact that on the basis of analyzing the mining data of complex structural rock blocks it is possible to determine the ore mass losses and their quantity and to lay the basis for the development of decisions on its extraction. For this purpose, the collected data on the mining of complex structural rock blocks, accounting the geological and industrial type of extracted ores, were considered in modeling the conditions and studying the parameters of technological processes, the implementation of which provides additional products. It was revealed that the ore mass from substandard thickness layers is delivered to the dumps, and ore mass losses have been estimated at 25-40 % per year. It is proved that determination of ore mass losses based on the analysis of data on mining of complex structural rock blocks, as well as timely solution of this issue can significantly increase the production efficiency of mining and technical system. Taking into account for the results obtained, the options for optimizing the production of the mining and engineering system were proposed.
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Date submitted2022-10-29
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Date accepted2023-10-25
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Date published2024-04-25
Assessment of rock massif sustainability in the area of the underground research laboratory (Nizhnekanskii Massif, Enisei site)
The study presents the results of the research on geodynamic and geological conditions of the Enisei site (Krasnoyarsk Krai), chosen for the construction of an underground research laboratory. The laboratory is being built at a depth of 500 m to assess the suitability of the rock mass for burying high-level radioactive waste. The rocks consist of weakly fractured gneisses, granites, and dikes of metadolerites. Field observations were conducted on bedrock outcrops. They included the determination of rock mass quality indicators, measurement of rock fracturing, and a rating classification of stability using N.Barton's method. GNSS observations were also made to monitor surface deformations. These data were used to develop a three-dimensional structural model, including lithology, fault disruptions, intrusive bodies, elastic-strength properties of rocks, and the sizes of zones influenced by faulting. It will serve as a basis for boundary conditions and the construction of three-dimensional variational models of stress-strain states, identifying zones of concentration of hazardous stresses, and planning in situ geomechanical experiments in underground mines of the laboratory. The obtained values of the modified QR index for the main types of rocks allowed their classification as stable and moderately stable, corresponding to strong and very strong rocks on Barton's scale and the massif rating according to geomechanical classification.
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Date submitted2023-01-16
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Date accepted2023-06-20
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Date published2024-04-25
Study on the thin layer drying and diffusion mechanism of low rank coal in Inner Mongolia and Yunnan
Coal is one of the world's most important energy substances. China is rich in coal resources, accounting for more than 90 % of all ascertained fossil energy reserves. The consumption share of coal energy reaches 56.5 % in 2021. Due to the high moisture content of low-rank coal, it is easy to cause equipment blockage in the dry sorting process. This paper considers low-rank coal coming from Inner Mongolia (NM samples) and Yunnan (YN samples). The weight loss performance of the samples was analyzed using thermogravimetric experiments to determine the appropriate temperature for drying experiments. Thin-layer drying experiments were carried out at different temperature conditions. The drying characteristics of low-rank coal were that the higher the drying temperature, the shorter the drying completion time; the smaller the particle size, the shorter the drying completion time. The effective moisture diffusion coefficient was fitted using the Arrhenius equation. The effective water diffusion coefficient of NM samples was 5.07·10–11 - 9.58·10–11 m2/s. The effective water diffusion coefficients of the three different particle sizes of YN samples were 1.89·10–11 - 4.92·10–11 (–1 mm), 1.38·10–10 - 4.13·10–10 (1-3 mm), 5.26·10–10 - 1.49·10–9 (3-6 mm). The activation energy of Inner Mongolia lignite was 10.97 kJ/mol (–1 mm). The activation energies of Yunnan lignite with different particle sizes were 17.97 kJ/mol (–1 mm), 33.52 kJ/mol (1-3 mm), and 38.64 kJ/mol (3-6 mm). The drying process was simulated using empirical and semi-empirical formulas. The optimal model for Inner Mongolia samples was the Two-term diffusion model, and Yunnan samples were the Hii equation was used.
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Date submitted2022-05-20
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Date accepted2023-06-20
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Date published2024-02-29
Increasing the quality of zeolite-bearing rocks from Eastern Transbaikalia by applying directed energy
This paper presents the use of accelerated electrons to treat zeolite-bearing rocks from Eastern Transbaikalia to increase the efficiency of separating zeolites from rock-forming minerals via electromagnetic separation. The effectiveness of the liberation of zeolite minerals using accelerated electrons was analyzed. The results of dry electromagnetic separation of zeolite-bearing rocks are presented. The dependence of the extraction of iron-bearing minerals from zeolite-bearing rocks by electromagnetic separation on the magnetic field intensity for different particle sizes has been established. The main methods of zeolite-bearing rock enrichment and ore preparation were determined. A technological scheme for processing zeolite-bearing rocks, based on the use of accelerated electron treatment at the ore preparation stage, is presented, significantly improving the zeolite production quality.
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Date submitted2023-07-04
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Date accepted2023-09-20
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Date published2023-10-27
Structure maintenance experience and the need to control the soils thermal regime in permafrost areas
- Authors:
- Anatolii V. Brushkov
- Andrei G. Alekseev
- Svetlana V. Badina
- Dmitrii S. Drozdov
- Vladimir A. Dubrovin
- Oleg V. Zhdaneev
- Mikhail N. Zheleznyak
- Vladimir P. Melnikov
- Sergei N. Okunev
- Aleksei B. Osokin
- Nikolai A. Ostarkov
- Marat R. Sadurtinov
- Dmitrii O. Sergeev
- Roman Yu. Fedorov
- Konstantin N. Frolov
The risks of reducing the stability of buildings and structures are increasing in conditions of climate change and the active development of the territories under the influence of natural and anthropogenic factors. The main causes include: loss of the bearing capacity of frozen soils, various geocryological processes, errors at the stages of design, construction and operation of facilities. Main actual task when conducting research and industrial operations in the cryolithozone is monitoring and, if necessary, managing thermal processes in the permafrost layers interacting with facilities. In this article the obtained positive experience of various technologies applying at various stages of the life cycle of civil and industrial facilities was analyzed. It helps to eliminate or prevent the structure deformation or destruction under the influence of climate change. The methods of permafrost stabilization used in the oil and gas industry in process of industrial infrastructure development of the fields have been studied – freezing (cooling) of foundation soils during construction on heterogeneous foundations. The solution to the problems of minimizing accidents when locating production wells in the permafrost zone of the Yamal Peninsula is considered using the example of an oil and gas condensate field and restoring of the temperature regime of perennial unfrozen soils in areas of valve units of main gas pipelines. An assessment of methods used to maintain the industrial and residential infrastructure within the northern municipalities that ensure the functioning of the fuel and energy complex of the Russian Federation in the Arctic was made. The systems of thermal stabilization in the foundations of buildings and industrial facilities built and operated on permafrost soils allow to fully use the high strength and low deformability of frozen grounds. It ensures the state's long-term plans of the industrial development in the Arctic.
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Date submitted2022-06-27
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Date accepted2023-06-20
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Date published2023-12-25
Analysis of the problems of high-quality drinking water extraction from underground water intakes on Vysotsky Island in the Vyborg district of the Leningrad region
This article presents the results of drilling, experimental filtration work and laboratory studies aimed at assessing the resources and quality of groundwater in the licensed area of Vysotsky Island located in the Leningrad region, in the Gulf of Finland in accordance with the requirements of regulatory documents. Analysis of the results of hydrochemical studies and their comparison with data on water intakes in adjacent areas gives the right to conclude that it is possible to classify a hydrogeological unit as a different type of resource formation than those located in the surrounding areas. Groundwater in this area is confined to an unexplored deep fractured regional high-pressure zone. According to the received data, the explored water intake can be attributed to a unique groundwater deposit, which has an uncharacteristic composition of groundwater in the north of the Leningrad region, which may be due to the mixing of modern sediments and relict waters of the Baltic glacial lake. The stability of groundwater characteristics is confirmed by long-term monitoring.
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Date submitted2022-10-30
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Date accepted2023-09-20
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Date published2024-02-29
Combined method of phytoremediation and electrical treatment for cleaning contaminated areas of the oil complex
The scale of land pollution with oil waste necessitates the use of economical and effective methods of recultivation. Phytoremediation is one of the simplest methods, but it has a number of limitations, so additional preparation of the territory is often required before it is carried out. Preliminary electrical preparation and subsequent seeding of special phytoremediants are of interest. Passing a constant electric current through the soil volume under a low voltage removes toxicants from deep soil layers even with flooding. In addition, it reduces pollutant content in the upper layer, where the plants root system is located, which creates more favorable conditions for phytoremediants. Adequately selected types of plants will ensure additional soil cleaning, improve its structure and air exchange. The results of two research directions are presented. Experiments on the study of plant resistance to oil-contaminated soil substrate allowed establishing contamination thresholds at which it is advisable to sow a particular species, and to choose optimal phytoremediants. The study of the oil-containing soil cleaning in a monocathodocentric electrochemical installation with the fixation of main characteristics (oil products concentration, soil temperature, volt-ampere characteristics) allows us to develop technical measures to prepare territories for phytoremediation taking into account the relief features.
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Date submitted2021-10-27
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Date accepted2023-06-20
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Date published2023-12-25
Geomechanical analysis of the impact of the new tunnels construction in the vicinity of existing underground subway structures on the state of the soil massif
The specificity of the behavior of the soil massif near the tunnel under construction in difficult mining conditions is considered. It was revealed through the joint interpretation of the results of geophysical measurements in the tunnel and computer simulation. The results of field geophysical studies to identify areas of decompacted soil behind the lining in two existing tunnels during successive drilling of two new tunnels under them are described. A method to analyze the response of the lining to impact was used providing for the calculation of its energy. It has been established that the decompaction zones are mainly located in the lateral lower areas of the tunnel. To substantiate the mechanism of formation of cavities, computer simulations were carried out using the finite element method with the COMSOL Multiphysics software. The finite element model is built on the Drucker – Prager criterion in the variant of a two-dimensional problem statement. It is shown that at the initial position of two old tunnels, the areas of decompaction can develop mainly on the sides. The position of the zones changes significantly when excavating two new tunnels. Soil decompaction zones appear between the tunnels and there is a tendency for the areas to spread to the upper point of the tunnel. According to geophysical data time delays in the impact of new tunnels on the existing line are noted, as well as a decrease in the size of decompacted soil areas over time. There is a satisfactory agreement between the positions of the decompaction areas and voids obtained by the geophysical method and the results of numerical simulation.
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Date submitted2023-07-19
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Date accepted2023-07-19
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Date published2023-07-19
Energy efficiency in the mineral resources and raw materials complex
Energy efficiency and energy saving at all times and especially at the present stage of development of industry and economy have played an extremely important role. Regardless of which countries and according to what criteria they build energy development plans, energy efficiency and energy saving are always a priority. This fully applies to the mineral resources complex, in which energy consumption as a whole makes up a large share of total consumption. The resources mined in the mineral resources complex are themselves a source of energy. The energy sector is evolving in many ways. Many scientific works, the results of which are reflected in publications, confirm the relevance of research in the energy efficiency field. But the approach to individual decisions in the mineral resource industry is specific and it is worth of separate consideration. Recently, much attention has been paid to “green energy” and renewable energy sources. However, energy efficiency in the field of traditional generation and consumption remains an urgent problem and its solution is in constant development. One of the main directions for improving energy efficiency is the development of autonomous systems for the electrical and thermal power engineering. All these problems are reflected in a special volume of the Journal of the Mining Institute, the articles are divided into four sections: energy efficiency of the electric drive in the mineral resources complex (MRC); energy efficiency of industrial plants and enterprises in MRC; power quality and renewable sources in MRC; autonomous power supply systems in MRC. The presented articles contain valuable material from the scientific and practical points of view and can form the basis for further research in the energy efficiency field.
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Date submitted2022-10-26
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Date accepted2023-02-13
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Date published2023-07-19
Determination of the grid impedance in power consumption modes with harmonics
The paper investigates the harmonic impedance determination of the power supply system of a mining enterprise. This parameter is important when calculating modes with voltage distortions, since the determined parameters of harmonic currents and voltages significantly depend on its value, which allow the most accurate modeling of processes in the presence of distortions in voltage and current. The power supply system of subsurface mining is considered, which is characterized by a significant branching of the electrical network and the presence of powerful nonlinear loads leading to a decrease in the power quality at a production site. The modernization of the mining process, the integration of automated electrical drive systems, renewable energy sources, energy-saving technologies lead to an increase in the energy efficiency of production, but also to a decrease in the power quality, in particular, to an increase in the level of voltage harmonics. The problem of determining the grid harmonic impedance is solved in order to improve the quality of design and operation of power supply systems for mining enterprises, taking into account the peculiarities of their workload in the extraction of solid minerals by underground method. The paper considers the possibility of determining the grid impedance based on the measurement of non-characteristic harmonics generated by a special nonlinear load. A thyristor power controller based on phase regulation of the output voltage is considered as such a load. Simulation computer modeling and experimental studies on a laboratory test bench are used to confirm the proposed method. The recommendations for selecting load parameters and measuring device connection nodes have been developed.
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Date submitted2022-04-08
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Date accepted2023-03-02
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Date published2023-04-25
Geochemical properties and transformation of the microelement composition of soils during the development of primary diamond deposits in Yakutia
Extraction of diamonds from primary deposits in Siberia is associated with the development of kimberlite pipes in challenging environmental conditions, accompanied by a complex impact on the environment. The article presents the results of monitoring the soil cover of the Nakyn kimberlite field in the Yakutia diamond province, which is affected by the facilities of the Nyurba Mining and Processing Division. Development of primary diamond deposits has a large-scale impact on the subsoil, topography, and soil cover: creation of the world's largest quarries, formation of dumps more than 100 m high, arrangement of extensive tailings, formation of solid and liquid industrial wastes of various chemical composition. The research is aimed at studying the spatial and temporal patterns of the technogenic impact on the soil cover, identifying the nature and level of transformation of the microelement composition of soils based on the analysis of the intra-profile and lateral distribution of mobile forms of trace elements. The study targets in 2007-2018 were zonal types of permafrost soils of northern taiga landscapes, cryozems, occupying 84 % of the total study area, which are characterized by biogenic accumulation of mobile forms of Ni, Mn, and Cd in the upper AO, A cr horizons, and Cr, Ni, Co, Mn, Cu in the suprapermafrost CR horizon. We found out that the contamination of the soil cover of the industrial site at the Nyurba Mining and Processing Division is of a multielement nature with local highly to very highly contaminated areas. Over a ten-year observation period, areas of stable soil contamination are formed, where the main pollutants are mobile forms of Mn, Zn, Ni. We suggest that against the background of a natural geochemical anomaly associated with trap and kimberlite magmatism, technogenic anomalies are formed in the surface horizons of soils. They are spatially linked to technogenically transformed landscapes. One of the sources of pollutants is the dispersion of the solid phase of dust emissions in the direction of the prevailing winds, which leads to the formation of soils with abnormally high contents of mobile forms of Mn, Zn, Ni.
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Date submitted2022-11-04
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Date accepted2023-03-03
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Date published2023-04-25
Efficiency of acid sulphate soils reclamation in coal mining areas
During the development of coal deposits, acid mine waters flowing to the surface cause the formation of acid sulphate soils. We study the effectiveness of soil reclamation by agrochemical and geochemical methods at the site of acid mine water discharge in the Kizel Coal Basin, carried out in 2005 using alkaline waste from soda production and activated sludge. A technosol with a stable phytocenosis was detected on the reclaimed site, and soddy-podzolic soil buried under the technogenic soil layer with no vegetation on the non-reclaimed site. The buried soddy-podzolic soil retains a strong acid рН concentration Н 2 О = 3. A high content of organic matter (8-1.5 %) is caused by carbonaceous particles; the presence of sulphide minerals reaches a depth of 40 cm. Technosol has a slightly acid pH reaction H 2 O = 5.5, the content of organic matter due to the use of activated sludge is 19-65 %, the presence of sulphide minerals reaches a depth of 20-40 cm. The total iron content in the upper layers of the technosol did not change (190-200 g/kg), the excess over the background reaches 15 times. There is no contamination with heavy metals and trace elements, single elevated concentrations of Li, Se, B and V are found.
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Date submitted2022-05-03
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Date accepted2022-11-22
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Date published2023-02-27
Development of methodology for scenario analysis of investment projects of enterprises of the mineral resource complex
Theoretical and applied aspects of scenario analysis of investment projects of enterprises in the mineral resource sector of the economy are considered, its advantages and disadvantages are analyzed. Taking into account the organizational and economic features of mineral resources management, a number of new modifications of the scenario analysis method, aimed at solving an urgent problem - reducing the information uncertainty in assessing the expected efficiency and risk of investment projects, are proposed. The peculiarity of the proposed new modifications is the use of the interval-probabilistic approach in the implementation of the scenario analysis procedure. This approach is based on a moderately pessimistic system of preferences in obtaining point values of the investment project initial parameters. Fishburn estimates and the hierarchy analysis method were used to reduce subjective uncertainty. The maximum likelihood values in the sense of the maximum a priori probability are used as expected estimates. An additional indicator of risk assessment, which characterizes the probability of the event that the net present value of the project will take a value less than the specified one, is proposed. When analyzing one project, this indicator is more informative than the standard deviation. A statistical hypothesis was tested on the improvement of the validity of investment decisions developed using the modified scenario analysis method compared to the standard method.
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Date submitted2022-03-09
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Date accepted2022-11-17
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Date published2023-02-27
Development of methodology for economic evaluation of land plots for the extraction and processing of solid minerals
The Russian economy has a pronounced resource specialization; in many regions, subsoil use is a backbone or one of the main areas of the economy. In these conditions, the improvement of the methodology for the economic evaluation of lands on which mining enterprises are located is of particular relevance. On the basis of the existing experience in assessing industrial land, the authors present a developed methodology for determining the cadastral value of land plots where mining enterprises are located, taking into account their industry characteristics and the specifics of production and commercial activities. At the same time, cadastral valuation is considered as a specific form of economic valuation. Particular emphasis is placed on the importance of taking into account the cost factors that have the greatest impact on the formation of the cost of land for the extraction and processing of solid minerals, and the method of assessment depending on the characteristics of the object. To carry out theoretical research, the methods of analysis and synthesis of legal and scientific and technical literature in the field of cadastral and market valuation of land were used in the work. The practical part is based on the application of expert methods, including the method of analysis of hierarchies, system and logical analysis. The method of M.A.Svitelskaya was chosen as the basis, which presents a combination of modified methods of statistical (regression) modeling and modeling based on specific indicators of cadastral value. The use of this technique in economic practice contributes to increasing the efficiency of cadastral valuation and the objectivity of its results.
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Date submitted2022-05-12
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Date accepted2022-11-17
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Date published2023-04-25
Microbiological remediation of oil-contaminated soils
- Authors:
- Irina D. Sozina
- Aleksandr S. Danilov
Microbiological remediation is a promising technology for the elimination of environmental contamination by oil and petroleum products, based on the use of the metabolic potential of microorganisms. The issue of environmental contamination by crude oil and its refined products is relevant in the Russian Federation since the oil industry is one of the leading sectors of the country. Mechanical and physico-chemical methods of treatment are widely used to clean oil-contaminated soils. However, the methods belonging to these groups have a number of significant drawbacks, which actualizes the development of new methods (mainly biological), since they are more environmentally friendly, cost-effective, less labor-intensive, and do not require the use of technical capacities. Various bio-based products based on strains and consortia of microorganisms have been developed that have proven effectiveness. They include certain genera of bacteria, microscopic fungi, and microalgae, substances or materials acting as sorbents of biological agents and designed to retain them in the soil and increase the efficiency of bioremediation, as well as some nutrients. Statistical data, the most effective methods, and technologies, as well as cases of using microorganisms to restore oil-contaminated soils in various climatic conditions are presented.
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Date submitted2022-05-12
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Date accepted2022-09-15
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Date published2022-12-29
Problem solution analysis on finding the velocity distribution for laminar flow of a non-linear viscous flushing fluid in the annular space of a well
- Authors:
- Vasiliy I. Nikitin
Modern drilling fluids are non-linear viscous media with an initial shear stress. In classical scientific works on hydromechanical modeling of drilling fluids motion in pipes and annular channels the Shvedov – Bingham approximation and Ostwald – de Waale power-law model were used, which did not fully account for behavior of technological fluids in a wide range of shear rates. This article presents a numerical solution for a mathematical model of drilling fluid motion of the three-parameter Herschel – Bulkley rheological model in the annular space of the well. The Herschel – Bulkley model in the rheological equation takes into account the presence of initial shear stress and a tendency for viscosity to change with shear rate, which distinguishes it from the Ostwald – de Waale and Shvedov – Bingham models. The target function in solving the equation of motion is the velocity distribution in the radial direction of the upward flow of the flushing fluid. The analysis of obtained solution is based on the theory of velocity profile influence on quality of cuttings removal during wellbore cleaning. Due to peculiarities of mathematical statement of the task, which supposes necessity of differential equation of motion solution, Wolfram Mathematica computational software has been used as a calculation tool. The analysis of numerical solution allowed to draw conclusions about the possibility of its application in evaluation of velocity profile when drilling fluid moves in annular space of the well. The possibility for application of modified excess coefficient as a relative quantitative parameter for evaluation of velocity profile uniformity was substantiated.
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Date submitted2021-11-17
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Date accepted2022-04-06
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Date published2022-11-10
Method for predicting the stress state of the lining of underground structures of quasi-rectangular and arched forms
- Authors:
- Maksim A. Karasev
- Tien Tai Nguyen
A method for predicting the stress-strain state of the lining of underground structures, the shape of the cross-section of which is different from the circular outline, is considered. The main task of the study is to develop a methodology for assessing the influence of the parameters of the cross-section shape of underground structures on the stress state of the lining. To solve this problem, a method for calculating the stress state of the lining for arched tunnels with a reverse arch and quasi-rectangular forms is substantiated and developed. The methodology was tested, which showed that the accuracy of the prediction of the stress state of the lining is sufficient to perform practical calculations. An algorithm for multivariate analysis of the influence of the cross-sectional shape of underground structures of arched and quasi-rectangular shapes on the stress state of the lining is proposed. Parametric calculations were performed using the developed algorithm and regularities of the formation of the stress state of the lining of underground structures for various engineering and geological conditions, as well as the initial stress state field, were obtained. A quantitative assessment of the influence of geometric parameters of tunnels on their stress-strain state was performed.
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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 submitted2021-10-08
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Date accepted2022-01-24
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Date published2022-04-29
Methodology for thermal desorption treatment of local soil pollution by oil products at the facilities of the mineral resource industry
- Authors:
- Mariya A. Pashkevich
- Marina V. Bykova
The analysis of the main environmental consequences of leaks and local spills of petroleum products at the enterprises of the mineral resource complex is presented. It is established that the problem of soil contamination with petroleum products at the facilities of the mineral resource complex and enterprises of other industries is caused by significant volumes of consumption of the main types of oil products. Based on the results of the author's previous field research, a series of experiments was carried out, consisting in modeling artificial soil pollution with petroleum products such as gasoline, diesel fuel, highly refined oil, motor oil, and transmission oil, followed by their purification by heat treatment at temperatures of 150, 200, and 250 °C. The 250 °C limit of the heating temperature was set due to the need to partially preserve the structure and quality of the soil after heat treatment to preserve its fertility. When the processing temperature rises to 450 °C, all humates are completely burned out and, as a result, productivity is lost. Confirmation is provided by the results of experiments to determine the humus content in uncontaminated soil and soil treated at different temperatures. It was found that at a maximum processing temperature of 250 °C, about 50 % of the initial organic carbon content is preserved. According to the results of the conducted experimental studies, the dependences of the required processing temperature on the concentration of petroleum products to reduce the concentration of petroleum products to an acceptable level have been established. The methodology of thermal desorption cleaning of soils with varying degrees of contamination at enterprises of the mineral resource complex is presented.