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STUDIES OF THE SHAPED CHARGES EFFECT WITH A HEMISPHERICAL ECCENTRIC SHAPE RECESS FOR THE ROCKS DESTRUCTION

Dam Trong Thang, Vladimir A. Belin, Tran Van Doanh

Abstract. The method of outdoor installation of explosive charges is usually used in the destruction of rocks in conditions in which the method of drilling and blasting using borehole or borehole charges is difficult to apply due to objective conditions. The productivity of rock destruction by the outdoor installation of a concentrated charge is very low. This is due to the fact that such an explosion is characterized by a large loss of energy in the environment. The destruction of rocks by an explosion using shaped charges (CW) to destroy the rock is one solution to increase the useful energy of the destruction of the rock compared to charges placed outside. To achieve the optimal effect of destruction of the rock by cumulative charges, it is necessary to, so that for each type of rock, a specific type of shaped charges can be determined with the appropriate performance and efficiency of the use of explosives. The stronger the rock, the more efficient the short-circuit should be, and vice versa. Thus, for effective rock crushing, it is necessary to develop and produce a number of different types of shaped charges. The use of shaped explosive charges allows you to increase the utilization rate of the useful energy of the explosion and increase the destruction zone of the rock. At a fixed mass of the explosive, the destructive effect of the explosive charge placed on the surface of the rock, it depends on the shape of the charge and the geometric parameters of the charge. Shaped charges with an eccentric hemispherical shape have a coefficient of use of the useful energy of the explosion for the destruction of rock, more than 2.4 times compared to conventional concentrated charges of the same mass.

Number of views: 400

EQUIPMENT MODIFICATION FOR FINE GRINDING OF MINERAL RAW MATERIALS

Valery N. Khetagurov, Evgeny S. Kamenetsky, Mikhail V. Gegelashvili, Azamat T. Marzoev

Introduction. The huge energy costs of fine and ultrafine grinding operations have led to numerous studies aimed at developing new devices and methods for producing powdered materials. The first way leads to an increase in specific productivity while maintaining energy consumption at approximately the same level. The second way allows not only to increase the specific productivity, but also to reduce the specific energy consumption, since with a decrease in the exposure time, the body is more easily deformed and destroyed. The grinders in which the intensification of the destruction process is carried out in the first way can include planetary and vibrating mills. The second method of intensification is used in jet and various types of centrifugal mills. It is determined that vertical centrifugal mills are the equipment of a new type that can effectively perform grinding operations at high technological indicators and low energy consumption. The purpose of the research. Development of measures for obtaining a finely dispersed product by destroying mineral raw materials in vertical centrifugal mills by mechanical means. Research methodology. The paper uses a comprehensive research method: analysis of the state of grinding equipment according to literary and patent sources; development of mathematical models of the movement of bulk material in the working space of a vertical centrifugal mill based on the Navie-Stokes equations; computer modeling of the movement of the crushed material using the OpenFOAM package for solving hydrodynamic equations; a solver program was created to perform calculations, implementing the SIMPLER algorithm and using the MRF model; laboratory experiments; granulometric method for the analysis of grinding products; fractional analysis of crushed material with a grain size of 0.08 mm using an X-ray analytical centrifuge ВrооkhаvеnBI-ХDС. The development of measures for the effective evacuation of the crushed product from the working space of a centrifugal mill was evaluated by comparative tests of mills using various design solutions. Research results and discussion 1. It is established that vertical centrifugal mills are the devices of a new type capable of effectively performing grinding operations at high technological indicators and low energy consumption. 2. A mathematical model of the movement of bulk material in the working space of a vertical centrifugal mill has been developed based on the Navier-Stokes equations, which allows determining the speed and direction of movement of material layers at any point in the working space, the energy costs for their movement, the influence of the height of the material column on the nature of its movement in the space above the rotor. 3. The directions of increasing the efficiency of grinding mineral raw materials in a vertical centrifugal mill are determined by reducing the number of radial ribs installed in the cavity of the mill rotor; making cutouts in the radial ribs of the rotor, in the area near the rotor hub; installing coaxial rings in the working space of the mill above the rotor. 4. A method of effective evacuation of the crushed product from the mill body by installing additional screening surfaces in the peripheral part of the working space of the mill has been developed. 5. For the first time, the distribution of the granulometric composition of fine and medium - dispersed crushed product obtained as a result of processing lump dolomite in a centrifugal mill was obtained. It was found that particles with a size class of -0.08 + 0.03 mm are absent in the output of the crushed product from the mill. Conclusions. A mass-produced vertical centrifugal mill will find its effective application at enterprises of the Russian Federation for the preparation of powdered materials and will allow to obtain a significant effect by r

Number of views: 411

THE MAIN SCIENTIFIC ACTIVITY TRENDS OF NORTH CAUCASIAN INSTITUTE OF MINING AND METALLURGY (STATE TECHNOLOGICAL UNIVERSITY) IN THE STUDY AND SOLUTION OF THE PROBLEM OF COMPLEX AND ENVIRONMENTALLY SAFE PROCESSING OF NATURAL AND TECHNOGENIC MINERAL RAW MATERIALS

Yuri V. Dmitrak

Abstract. Introduction. The result of many years research of the university scientific community in the field of topical issues of complex processing of natural and man-made mineral raw materials was the creation of a scientific school “Dynamics of working bodies of machines and equipment for fine grinding of rocks” under the leadership of Professor Dmitrak Yu. V. Research results. The dynamic parameters of the grinding bodies are determined directly in the mill grinding chamber which ensure the contactless transmission of information from the grinding ball to the receiving device. A new method of materials self-grinding and the design of a vertical centrifugal mill based on it has been developed. The mill tests during the grinding waste from the production of ceramic products (the battle of insulators, crushed mullite bricks) showed high efficiency and prospects. The tests of a laboratory vibrating mill with one grinding chamber and a rotor diameter of 250 mm for grinding dolomite were carried out. The experiments have shown the possibility of creating vibrating mills for solid materials grinding. In the development of the work of I. N. Plaksin on the flotation of ores with the jet movement of products in the scheme tested by him together with employees in the conditions of the Tekeli processing plant, the modes of joint processing of ores and gold placers were developed at the NCIMM (GTU). It was established that with the unprofitable individual development of alluvial gold mining waste, a positive economic effect can be obtained through their joint processing with ore gold reserves by fine-tuning the concentrate extracted from man-made raw materials by gravitational enrichment methods at a stationary processing plant. It is proved that the addition of the gravitational technology of alluvial gold extraction by flotation methods provides an increase in annual gold production by ~38 % due to the additional extraction of “resistant” forms of gold for gravitational methods. It has been proved in laboratory conditions that the waste slag of the Copper plant of “Ltd. MMP Norilsk Nickel” can be disposed of by joint processing with the ore of current production. It is established that the technology development using metal leaching is promising for the development of Sadonsky plant deposits.

Number of views: 203

PROCESS WATER AND WASTE MANAGEMENT IN OPEN CAST QUARRIES AND THE POSSIBILITY OF FINE SEDIMENTS RATIONAL USE

J. M. Annandale, T. L. Gorbunova, N. K. Gudkova

The article provides an overview of different type of water settlement treatment systems in the open cast extractives industry and provides descriptions of the potential hazards from fine particles and suspended solid pollution as a result of mining operations, concentration and process waste management which determines that a lack of mine process utilization leads to fines accumulations in the working areas. Several solutions and alternative means are offered for utilization and re-use of settled material, consisting of fines/dust/silt components within various industries and agricultural enterprises, such as manufacturing artificial soil and culture media for the use as bio-filtration. The article also explores the potential technical, economical and legal challenges identified as well as the issues of the use of mining fines commercial utilization including taxation regimes, insufficient product specification and necessity for additional treatment of the material.

Number of views: 606

LAND USE AND POSSIBILITIES OF REGULATING ANTHROPOGENIC LOADS ON THE MOUNTAIN LANDSCAPES OF THE NORTHERN MACRO-SLOPE OF THE GREAT CAUCASUS (On the example of the Karasu River valley)

Alla V. Voskova, Aleksei N. Gunya, Vadim A. Karavayev, Dmitry M. Mar`inskih

Aim. The basis for the optimal development of mountain regions is the regulation of anthropogenic impact on natural land-scapes. The purpose of the study is to assess the state of natural landscapes of the highlands of the Central Caucasus and substantiate effective mechanisms that regulate economic activity in territories adjacent to nature conservation ones. On the example of the Karasu river valley, which is representative of the Northern macro slope of the Greater Caucasus, analyzes the features of anthropogenic impact in the form of recreation, tourism and grazing.
Research methods. The key method of this research is the making of maps showing the landscape structure of the area under consideration, the spatial features of the location of exogenous processes and types of nature management.
Using the above maps, the features of the geological and geomorphological basis and landscape structure of the Karasu river valley were identified, the features of modern nature management were characterized, the consequences of anthropogenic impact on natural landscapes were assessed, and the management approach were formulated to reduce the negative impact on the nature of mountain areas.
To assess the land cover, high-resolution satellite images were used, according to which the difference vegetation in-dex was calculated, which most clearly distinguishes the main types of the cover.
Results. Within the boundaries of the study area, the role of shrub-meadow vegetation of the subalpine zone, which performs a water-retaining function, is especially significant. The destruction of land cover due to overgrazing, the construction of capital facilities, and other types of economic activity without the necessary protective engineering and land reclamation measures favors the development of destructive exogenous processes. The border of the reserved and non-reserved territories is smooth (not sharp).
Conclusions. The gradual transition from landscapes with a reserved regime to landscapes with different uses requires a revision of the concept of nature protection in the direction of developing measures on the principle of “protection in use.” Particular attention should be paid to the conservation of sub-alpine meadows, alpine meadows and wastelands, bog complexes, which have a high species diversity, the presence of endemic species and are small in area. The main environmental measures for these communities are state monitoring and the maximum possible reduction in anthropogenic impact.

Number of views: 622

MICROELEMENT COMPOSITION OF SOD-CARBONATE SOILS OF THE NORTH-WEST CAUCASUS

Tatiana V. Degtyareva, Yuri I. Karaev, Andrey A. Likhovid, Alexey V. Lysenko

The aim of the work is to study the peculiarities of the formation of the microelement composition of sod-carbonate soils of the North-West Caucasus. 
Methods: Determination of the features of the formation of the microelement composition of sod-carbonate soils was carried out in the western part of the Labino-Malkinsky landscape district of forest-steppes and settled meadows. 
The Kuestov District occupies a band of ridges of the North-western Caucasus, composed of limestones, dolomites and sandstones of the Jurassic (K) and Cretaceous (k) periods. 
Chemical analysis of the soil was performed by conventional methods. The content of strongly bound compounds Pb, Cu, Zn, and Cd by acid decomposition using 5 M HNO3 was analyzed in the humus horizon of soils. The metal content was determined by the methods of inversion volt-amperometric and atomic absorption analyses. 
Results: In most cases, the microelement composition of sod-carbonate soils is characterized by the enrichment of Pb, Cu, Cd and depletion of Zn in comparison with the Clark soils. The constant anthropogenic input of pollutants into the soil as a depositing medium directly affects the trace element composition-the soils are intensively enriched with all the elements considered, especially strongly accumulated on CD and PB. 
In the radial distribution of trace elements between sod-carbonate soils and the soil-forming rock, a high intensity of accumulation of chemical elements in the humus horizon of soils was revealed. The intensity of the redistribution of trace elements in soils is largely determined by the position in the terrain. Within the Cretaceous cuesta, high Cd contents are typical for plakor soils, Cu and Zn-for the soils of the slope of the beam. On the slope of the Jurassic questi higher contents of Pb, Cd and Cu are typical for soils of placorestan cavage array Zn for soils of steep hillside with oak and beech forests.
Conclusions: The microelement composition of sod-carbonate soils is a consequence of such soil-forming processes as humification, humus accumulation, leaching, glinting, and loess age, the specifics of which are largely determined by calcium carbonates. The microelement composition of sod-carbonate soils reflects the most significant features of the microelement composition of soil-forming rocks, which are characterized by low Zn content. The possible aerotechnogenic intake of trace elements affects the intensity of the radial accumulation of trace elements in the soil relative to the rocks. 
The degree of transformation of the microelement composition of anthropogenic disturbed soils depends on the intensity of anthropogenic impact on the soil. The conducted research is important in the aspect of revealing the regularities of the formation of the microelement composition of the soil as a depositing component of the landscape in modern conditions of anthropogenic pressure.

Number of views: 652

MEDICAL-GEOGRAPHIC FACTORS OF POPULATION HEALTH IN THE NORTH OSSETIA

Alexander D. Badov, Oleg A. Badov, Larisa H. Dzakhova, Juliet B. Byazrova

Introduction. Medico-geographical researches are now becoming particularly relevant, since geographic methods with their inherent complexity, diversity, vision of the territory, the identification of medical geographic factors and the application of cartographic methods can explain the basis of those processes and phenomena that occur on the territory of our country and its regions in terms of the morbidity of the population and find ways to optimize the health system.
Methods. Medical geography studies the impact of natural, socio-economic and environmental factors on the health of the population, examines the geography of the spread of diseases and identifies the territorial organization of health. 
Particular attention is paid to the complexity of research; The identification of interaction, mutual development and mutual influence of geographic factors affecting the health of the population in a particular region, as well as the application of GIS technologies and cartographic methods.
Results (discussion). The natural conditions of North Os-setia (excluding the highlands) are generally favorable for the population living. Their diversity (despite the limited territory) leads to significant differences in the level and structure of the population morbidity. Within the republic there are five medical-geographical zones, each of which has its own natural-focal diseases. So, for example, rabies, echinococcosis, trichinosis, intestinal infection, leptospirosis, tularemia are characteristic for the steppe zone (the north of the republic); For the forest zone – ascaridosis, endemic goiter, dental caries, echinococcosis, rabies, trichinosis, leptospirosis. Congenital dislocation of the hip is common in the mountainous zone. 
And  girls get this disease five times more often than boys. In addition, almost all of the republic is characterized by a shortage of fluoride, iodine and some other elements.
Conclusions. The study of the geographical factors of the morbidity of the population is of great practical importance since it allows developing measures aimed at preventing many diseases.

Number of views: 602

ON VARIABILITY OF THE VEGETATION INDEX NDVI IN THE FOOTHILL AREAS OF THE NORTHERN CAUCASUS ACCORDING TO SATELLITE MEASUREMENTS

Evgeniy S. Kamenetsky, Anatoliy A. Radionov, Vasiliy Yu.Timchenko, Olga S. Panaetova

The study of long-term climatic changes is carried out based on the data of the normalized relative vegetation index NDVI, which is a characteristic of phytobiomass and is used to describe the ecological situation, the amount of contamination and productivity of land. This theoretical work is based on the statistical and mathematical processing of MODIS satellite data (EOS Terra, Aqua), with the help of which the temporal and spatial variations of the NDVI vegetation index for the southern regions of the Russian Federation are studied. Several regions were selected, which located in mountainous or foothill areas on the territory of the North Ossetia-Alania, located in the central part of the North Caucasus. For each region, 20-year data series were obtained, each point of which is the NDVI index averaged over two weeks. With the help of these data series, the annual behavior of the NDVI index and its long-term variation are investigated, which shows the shift of a favorable growing season to an earlier period of the year. The annual integral characteristic of the NDVI index was used, which characterizes the long-term changes in the vegetation index in the studied regions. A statistical analysis of the series of integral characteristics was carried out, the parameters of linear regression were determined. The behavior of these characteristics for the foothill and lowland regions of North Ossetia-Alania indicates the presence of long-term trends in the changing conditions of the growing season.
For the southern regions of the Russian Federation, observational data show a relationship between trends in NDVI changes with a long-term improvement in climatic conditions for plant vegetation and changes in conditions during cold periods of the year. This factor should be taken into account in economic activities in the southern regions of the Russian Federation.

Number of views: 561

HYDROCHEMISTRY OF MOUNTAIN PAMIR: TRIBUTARIES OF THE TRANSBOUNDARY PYANJ RIVER AND THEIR WATERS APPLICABILITY FOR IRRIGATION

I. Normatov, R. Anderson, N. Shermatov, P. Normatov

The results of chemical analyses of the waters of the transboundary Pyanj river tributaries – Gunt, Shakhdara, Bartang, Yazgulem and Vanch rivers are presented. The absence of stationary sources of pollution in the river basins and the dominance of rock weathering in the formation of hydrochemistry of the studied tributaries of the transboundary Pyanj River were established.

Number of views: 591

APPLICATION OF REMOTE SENSING TECHNOLOGY AND GIS FOR MONITORING THE CHANGE OF LAND COVER DUE TO THE IMPACT OF BAUXITE EXTRACTION. CASE STUDY IN TAN RAI BAUXITE PROJECT, LAM DONG PROVINCE, CENTRAL HIGHLANDS REGION OF VIETNAM

D. T. Vu, L. H. Trinh, T. H. Tong

In this study, we use Sentinel 2 satellite imagery and GIS technology to evaluate the dynamic of land cover around Tan Rai bauxite mining area, Lam Dong province (Central highland of Vietnam). 02 Sentinel 2 images taken on November 15, 2015 and December 3, 2020 with spatial resolution 10 m (band 2, 3, 4, 8) were used to classify the land cover using object-oriented classification method. The results of land cover classification are used for creating the land cover status maps from 2015, 2020, and then for mapping the land cover change in the period 2015 - 2020. The results obtained showed that there was a significant decrease in forest area, both dense forest and mixed forest, plantation forest. Meanwhile, the area of agricultural land and industrial crop land increased by about 10% in the period 2015 – 2020. The area of Tan Rai aluminum mining project in 2020 also increased to 376.47 hectares, nearly 2 times higher than 2015.

Number of views: 298
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ISSN 1998-4502 (Print)                                                            ISSN 2499-975Х (Online)