REGULARITIES OF CHANGES IN THE GAS-DYNAMIC AND GEOMECHANICAL SITUATION AT POTASH MINES

Mining operations in potash and salt deposits are complicated by gas emissions and gas dynamic phenomena. The analysis of a large number of gas dynamic phenomena and intense gas emissions at potash mines in Russia and Belarus allowed the authors to identify some patterns. In particular, it was found that the maximum number of gas dynamic phenomena occurs in the 7–10 year of operation of the mines. The purpose of the study is to analyze and identify available information on the influence of heliophysical and manmade factors on the state of rock massifs, which will allow purposefully predicting and preventing the manifestations of these factors, increasing labor safety and efficiency of mining enterprises. Research methods: methods of a full-scale mine experiment to determine the gas content of rocks and the gas content of workings, as well as analysis of statistical data. The results of the study showed that the analysis of data on 84 cases of gas dynamic phenomena at the mines of PJSC Uralkali revealed an increase in the volume of gas emissions from the developed lavas spaces at the mines of JSC Belaruskali as a result of a drop in barometric pressure on the surface. In conclusion, it can be noted that the combination of natural factors together with a powerful man-made impact on the environment creates certain prerequisites for disasters of various scales, ranging from destructive earthquakes to subsidence of mountain pressure, gas dynamic phenomena and intense gas emissions in mines and mines. The set of established patterns formed the basis for the development of a number of preventive measures that increase the safe working conditions of miners and the efficiency of mining enterprises.

DYNAMICS OF GAS EMISSION FROM EXPOSED SURFACE OF GAS-BEARING COAL SEAMS HAVING MEDIUM THICKNESS

The goal of the research was to clarify the regularities of the dynamics of gas release from the surface of the outcrop of the developed coal seam. The main research methods were theoretical methods of mathematical physics and non-equilibrium thermodynamics. Gas-bearing coal seams are usually mined underground. When driving development workings, outcropping surfaces of gas-bearing coal seams appear and gases in the seams under excessive pressure are released into the atmosphere of the mine workings. Gas-bearing coal seams are usually mined underground. When driving preparatory workings, surfaces of outcropping of gas-bearing coal seams arise and gases that are in the seams under excessive pressure are released into the atmosphere of the mine workings. The most important gas-dynamic characteristic of this process is the rate of gas release, which represents the volume of gases released from a unit area of exposure of a coal seam per unit of time. A generalized law of resistance for gas filtration in a rock mass is recommended, and a fairly rigorous thermodynamic substantiation is given. It is shown that the densities of gas mass flows in accordance with the postulate of their linear relationship with the driving forces are determined by the Onsager relation. The results obtained and their discussion is presented. Mathematical models are proposed for engineering calculations of the dynamics of methane release from the outcropping surface of medium-thick coal seams. The error of the adopted approximations does not exceed 3%. The intensity of methane release is directly related to the planogram of work in the working face. Analysis of this dependence indicates that during the extraction cycle, methane release increases due to an increase in the area of the gas-release surface. The main conclusions are as follows: mathematical modeling of the processes of gas movement in a porous sorbing medium using approximate mathematical models representing linearized equations of mathematical physics; the regularities of the dynamics of the rate of gas release from the surface of the outcrop of a gas-bearing coal seam is the theoretical basis for the mathematical description of the process of gas release; the use of a linearized hyperbolic filtration equation most accurately describes the processes of methane release from the outcropping surface of mined coal seams.

ASSESSMENT AND ANALYSIS OF AERODYNAMIC PARAMETERS OF AIR FLOWS FOR EFFECTIVE SELECTION OF AIR SUPPLY SCHEMES IN COAL MINES

The article examines a complex technical system on the example of air supply of coal mines, characterized by: multicomponent, a large number of quantitative and qualitative parameters, nonlinearity of interdependencies between them; incompleteness of information, the complexity of experimental research, the risks of dangerous situations and the catastrophic nature of their consequences; the uniqueness of the modes and conditions of the systems functioning. The aim of the work is to develop a methodology for assessing and analyzing the aerodynamic parameters of air flows for the effective selection of air supply schemes in coal mines using the decomposition method. Research methodology: the solution of the set tasks is based on modern methods of mathematical statistics; graph theory; decision theory; apparatus of mathematical logic; factor analysis; mathematical modeling; set theory; reliability theory and systems analysis. Research results. A method for the analysis and analytical modeling of complex technical systems of variable structure (CTS VS) is developed, focused on the features of these systems and their processes in conditions of incomplete information, different quality data on their state and functioning, which differs from the known ones by a combination of the capabilities of analytical and statistical approaches to the construction of CTS VS models, which allows to adapt to changes in systemic and external factors, improve the accuracy of modeling, and also typify the presentation of fuzzy situational features for effective management of the CTS VS. Conclusion. A method has been developed for assessing the reliability of the parameters of the CTS VS based on the algorithms for analyzing and assessing the reliability of the CTS VS, the algorithm for the formation of the most complete subsets listing in the graph all possible compatible subsets of a given set of vertices differing in that they are based on the analysis of enlarged states and decomposition of the structural diagram, which allows analytical and statistical studies to significantly increase the accuracy of assessing the reliability of CTS VS and reduce the amount of calculations. Result: the proposed methods were used to solve the problems of air distribution control in coal mines.

DETERMINANTS AND STRATEGIES OF MEDICAL TOURISM DEVELOPMENT BY TAKING THE SERVICE INTEGRATION AND TOURISM DESTINATION COMPETITIVENESS APPROACH (A Case Study Razavi Khorasan Province, Iran)

Introduction: Considering the significant position of medical tourism industry in global economy as well as Iran’s capabilities in this industry, the present research was conducted so as to compile the determinants of medical tourism development and present its respective strategies taking the approach of health village expansion and integrated service provision in Health Region No. 9 (Razavi Khorasan province). Methodology: This research was conducted by combining the qualitative and quantitative techniques. Data collection was done by content analysis followed by an interview and a survey administered to a number of key experts. Data were analyzed by MAXQDA-18, Expert Choice11 and Excel software and SOWT, fuzzy DEMATEL and AHP techniques. Findings: In this study, a framework of indexes was compiled and evaluated selected from different aspects taking the approach of service integration and destination competitiveness in the form of health villages. In the next phase, the status quo of Mashhad was categorized into 38 internal and 31 external factors to be prioritized. In the end, considering the identified factors and their interrelationships, the most important strategies were extracted and prioritized. Conclusions: To create a sustainable competitive market and attract more medical tourists, revealed that the respective authorities need to pay due attention to this issue proportionate to the indexes and strategies envisaged in the compilation, designing and implementation of policies and plans related to Mashhad’s medical tourism development in moving towards the creation of competitive advantage in an integrated way and promotion of medical tourism by focusing on the prioritization performed for the healthcare system.

OPTIMIZATION OF PARAMETERS OF FAN UNITS OF AIR COOLING DEVICES

Purpose of the study. Optimization of the parameters of high speed fan units of air coolers, the combination of which achieves the highest economic efficiency of fan units and, accordingly, the most rational range of specific speed values for the modes of maximum efficiency of fan units in combination with the relative diameter of the sleeve. Development of a mathematical model for determining the local values of the parameters of the efficiency of highspeed fan installations. Sustainable development of territories with active subsoil use is closely related to solving the problems of improving industrial safety and the efficiency of cooling the compressed gas at compressor stations of main gas pipelines, which actualizes the problem of mathematical modeling of energy conversion processes in the impellers of fan units of gas air coolers (AVO) to increase the competitiveness of the oil and gas complex RF in the context of globalization. Research methods. To optimize and determine the limiting combination of calculated parameters, the mathematical method of searching for the area of local maxima of a multiparameter problem in this part was performed in two stages: a mathematical model was built for determining the local values of the parameters that ensure the highest efficiency of fan installations with high speed; the most rational limiting combination of design parameters was determined, at which the highest economic efficiency of fan installations is achieved. Research results. The possibility of increasing the economic efficiency of axial fan units of high speed, made according to aerodynamic schemes with one impeller for gas air cooling devices, has been established. Using the mathematical analysis of the basic laws of axial turbomachines, equations for the efficiency of a fan unit and a fan are obtained, depending on the specific speed. Formulas are obtained for the maximum values of the efficiency of the fan and the fan unit of various specific speed depending on the coefficient of the consumpconsumption speed and on the relative diameter of the impeller sleeve. A method is proposed for constructing aerodynamic schemes of axial fan units for air-cooled gas coolers of the "K" type with maximum maximum values of efficiency for given values of specific speed, relative diameter of the impeller sleeve, aerodynamic quality of the impeller profiles, coefficient of aerodynamic resistance of the flow path of the coefficient of flow velocity. The possibility of creating a fan installation with a speed of ny ≥ 400 with an efficiency of at least ηy=0,86. Application area. Enterprises of the oil and gas complex of the Russian Federation for cooling compressed gas using AVO compressor stations of main gas pipelines.

POSSIBLE INFLUENCE OF A MAJOR INFERRED FAULT ON THE OCCURRENCE OF SINISTRAL TOP-TO-THE NW DEFORMATION IN THE ZAGROS HINTERLAND FOLD-AND-THRUST BELT, IRAN

In the present study, fault slip data, the geometry of en-echelon vein arrays (tension gash), and pressure-solution seams (stylolites), in the northeastern margin of Fars Province were analyzed. The results of this study indicate that in the time of the development of these structures, the maximum principal (σ1) stress axes were generally horizontal and directed towards NE-SW and ENE-WSW. This general direction is compatible with the expected directions of σ1 stress axes responsible for the occurrence of the sinistral top-to-the NW ductile and brittle-ductile shear zones of the area. This compatibility suggests a long-lasting stable stress condition over a long period and different pressure/temperature conditions. This longstanding constant stress state can be interpreted as the result of the occurrence of a major strike-slip NW-SE trending fault in the NE of the Zagros Hinterland Fold-and-Thrust Belt. The dextral activities of the Main Zagros Thrust and this inferred fault, which are subparallel, might result in the sinistral topto-the NW deformation in the area between this fault, which we named it Abarkuh Fault and the Main Deep Fault. This inferred fault has been covered by Quaternary alluvium of the Abarkuh plain, but the great age difference of rock units of the Esteghlal Anticline and its northeastern rock exposures, and the significant change in topography between the Abarkuh plain and its southwestern mountains can be two consequences of the existence of this probable fault.

LANDSLIDES RAINFALL THRESHOLDS APPROACHES FOR THE WESTERN GHATS INDIA AND THE NORTH CAUCASUS (Russia)

Knowing the duration, intensity and amount of precipitation triggering landslides is of great importance for landslide risk management. Global, regional and local studies carried out by the researchers revealed that the rainfall-induced landslides occur after rainfall exceeding a certain threshold value. The rainfall threshold is the minimum intensity or duration of rainfall required to initiate the landslide. The Rainfall threshold can be estimated from the daily rainfall data which is collected from the rainguage. The methodology used by Jaiswal and Van Westen and ITC Netherland are used for the present study. Daily data from particular rainguage station closer to the landslide location were considered. The 5Days Antecedent (5-AD) rainfall for each year from daily rainfall of landslide events calculated (for 5 days AD, add the previous 5 days of daily rainfall). Then the daily rainfall and the corresponding 5AD rainfall for the all the landslide event in the same period will be plotted. The relation could be presented as a straight line with negative slope of the type RT = p*R5AD + c, where p is the slope and c is the intercept. The present study is focused on the assessment of precipitation thresholds for landslides on different slopes prone to the landslides in Russia and India, which are characterized by very different geological, geomorphological and meteorological conditions. In this article, the main attention is paid to precipitation threshold criteria as the main driver of landslides in India compared to the North Caucasus, in order to find out the contribution of various factors to the processes of landslides for the development of an early warning system. In order to form the landslide inventory map of the territory of the North Caucasus, we used the data of the Information Bulletins on the state of the subsoil of the North Caucasian Federal District for 2019-2020. For all events, there is information about the genetic types of hazardous exogenous processes, activation factors, consequences and damage. Area of Dagestan was selected. Calculations were made for landslides and rockfalls. One can see that slopes of both lines are nearly same p=-0.11-0.12, while landslides need twice a precipitation more than rockfalls. Comparison with rain thresholds for India had shown that for the territory of Russia requires by an order of less total precipitation and precipitation per day. Perhaps, here it is necessary to take into account the contribution of other factors as well. This work is the first stage, and research will be continued. Subsequently, the influence of other factors on the formation of landslides and rockfalls will also be studied (the influence of earthquakes, man-made impacts, etc.) according to the data of various geophysical methods.

RESOURCE-SAVING TECHNOLOGIES FOR DEVELOPMENT OF MINERAL DEPOSITS

The relevance of the work is caused by the need to survive the mining industry during the protracted post-reform crisis and to minimize its negative impact on the ecology of the region through the development of technogenic mineral resources. Purpose of work. Substantiation of the possibility of replacing the traditional components of the filling composite with own or attracted man-made wastes after their processing to a level that meets the conditions of environmental safety and economic feasibility. Research methods: systematization, analysis and generalization of theoretical and experimental research in this area, as well as patent data. Results. A generalization is made, the result of an analysis of the mechanism and rates of accumulation of waste from mining and processing of mineral raw materials is given, and a multifactorial mathematical model of degradation of environmental ecosystems as a result of the impact of waste is formulated. A historical background is given and an assessment of the development of mineral deposits with backfilling with hardening mixtures based on utilized man-made waste in a closed cycle is given. A promising method of activating the binding components of the hardening mixture is recommended, treatment in a high-speed mill - disintegrator. The results of experimental studies of the possibility of using metallurgical slags of the Chusovoy metallurgical plant as a binder and as an inert filler of ore dressing wastes of PJSC Uralkali are given. It is shown that if the content of unrecovered metals in industrial waste is more than the background level, they can be disposed of after the extraction of metals within the framework of a single technological cycle of waste-free production. It is concluded that when preparing a filling composite, it is possible to replace traditional commercial components with man-made waste from mining and processing and metallurgical industries after extracting useful components from them and neutralizing hazardous impurities. The prospect of the transition of mining production to an innovative principle of organization, which excludes the storage of waste, is noted, for which it is advisable to combine physical-technical and physical-chemical technologies at the design stage in the technological process of resource development. Conclusions. The involvement of man-made waste in a closed production cycle increases the environmental and economic efficiency of enterprises. Conversion of production to minimize waste volumes and their use in their own or in related production is an effective step towards sustainable development of the mining region.

MODERN TECHNOLOGY OF TYRNYAUZ DEVELOPMENT

The relevance of the work is explained by the importance of the problem of restoring the industrial potential lost during the reforms at one of the large fields and minimizing its negative impact on the environment. Purpose of work. Substantiation of the possibility of reanimating the lost potential of mining enterprises through the use of combined technologies with the management of subsoil exploitation indicators based on the use of substandard raw materials after processing. Research methods: systematization, generalization and analysis of theoretical and experimental studies in this area, including those carried out at the considered fields. Recommended parameters of mining operations are determined by generalizing theory and practice, research results and analytical calculations based on assessing the behavior of discrete rocks in a massif with a gravitational-tectonic-structural stress field from the condition of consolidation of structural units. Results. A certificate was given on the reserves and development of tungsten and molybdenum deposits, taking into account the retrospective. The problem of restoration of mining production on the preserved infrastructure in comfortable natural conditions is formulated. The results of complex studies with the identification of the regularities of deformation of the rock mass are presented to assess the danger of destruction of the rock mass and the collapse of the earth's surface. Distinctive features of the field. The technologies for managing the state of the massifs with the details of their participation in geodynamic processes are characterized. Information on environmental pollution by metal-containing tailings waste is given and it is shown that this is a consequence of the imperfection of the applied technology of mining and processing of ores. An algorithm for the use of tailings for the preparation of hardening mixtures and a control system for the state of the massif are recommended. It was concluded that the restoration of the potential of enterprises is possible on the basis of a combined mining technology with factory processing of rich ores and leaching underground and in heaps of poor ores and enrichment wastes in disintegrators.

REGULARITIES OF THE MICROELEMENT COMPOSITION FORMATION OF SOILS UNDER THE MOUNTAIN-MEADOW VEGETATION OF THE GREATER CAUCASUS

Report. The purpose of the work is to identify the features of the formation of the microelement composition of soils under the mountain meadow vegetation of the Greater Caucasus based on the analysis of literary materials and the results of our own field research. Methods. The study of the microelement composition of soils under subalpine and alpine vegetation was carried out on the territory of the Teberdinsky State Biosphere Reserve. Traditional methods of soil-geochemical studies were used with the laying of soil sections, the selection of soil samples and their analysis for the content of four trace elements (Zn, Cu, Pb and Cd). Determination of trace elements was carried out by voltammetric and atomic absorption methods. The humus content was determined by the Tyurin method with wet salting, the pH of the water extract was determined potentiometrically. Statistical processing of the obtained data was performed in the Statistica 10 program. The microelement composition of soil-forming rocks was compared with the clarks of chemical elements in the upper part of the continental crust; the microelement composition of mountain-meadow soils was compared with the clarks of the soils of the world. The radial distribution of trace elements in the soil profile was analyzed. The qualitative trace element composition of soils was characterized as a sequence of decreasing the content of trace elements in the humus horizon. Results. It is established that the microelement composition of soils under the mountain-meadow vegetation of the Western Caucasus is formed under specific conditions that affect the course of soil processes. High solar insolation, low temperatures, intensive humidification throughout the year affects the features of the processes of humification, the formation of clay minerals in the soil and other products of intra-soil weathering. The predominance of acid hydrolysis processes leads to the predominant accumulation of aluminosilicates, Fe hydroxides, chelated organomineral complexes in the soil profile, which play a leading role in the binding of trace elements. The microelement composition of mountain-meadow soils under subalpine vegetation is formed with more intensive processes of humus formation and oglinivaniya. These soils are characterized by a more pronounced biogenic accumulation of Cu and Zn in the humus horizon, the illuvial nature of the Cd distribution is more pronounced. The microelement composicomposition of mountain-meadow soils under alpine and rock-scree vegetation is formed against the background of relatively weakened processes of humus formation, humus accumulation and oglinivaniya. This affects the lower intensity of biogenic accumulation of trace elements, their leaching into the lower part of the profile. Conclusions. The main regularities of the formation of the microelement composition of mountain-meadow soils are determined by the special conditions in which these soils develop. The fixation of trace elements in mountain-meadow soils occurs mainly on aluminosilicates, Fe, Mn hydroxides and chelated organomineral complexes, which largely form the silty fraction. The movement of silty particles along the soil profile leads to the redistribution of trace elements associated with them. The granulometric composition, which is an indicator of the content of the silty fraction and its distribution along the soil profile, is of great importance when characterizing the microelement composition of mountain meadow soils. The established regularities of the formation of the microelement composition of mountain-meadow soils allow us to determine the main directions of economic activity that will contribute to the preservation of their ecological state. This is, first of all, the rational use of pasture resources of mountain meadows with the introduction of a system of alternating mowing, changing the main pastures with spare ones during the year for their restoration. An important component should be monitoring changes in the trace element composition of mountain meadow soils, which will allow timely response to changes and make adjustments to the structure of the use of these soils.