Kateryna Sai

Dnipro University of Technology · Department of Mining Engineering and Education

Introduction Complex mineral mining leads to critical earth’s surface disturbance and environmental pollution from industrial waste. This research aims to comprehensively study, assess and show the current scale of the earth’s surface disturbances in the largest mining region of Ukraine – the Kryvyi Rih. Iron-ore Basin and suggests ways to improve...

Coal mine waste heaps are technogenic hazards that have been polluting the air, surface and groundwater, soil for years. At the UN Climate Conference COP26, held in November 2021 in Glasgow (Scotland), Ukraine and developed countries committed to carbon neutrality by 2060 and to abandoning fossil fuels by 2035. One of the largest technogenic factor...

The presented research is aimed at developing tools for quickly determining the geometric parameters of mining-technogenic landscape objects to solve various geotechnical and engineering problems, such as reclamation of lands disturbed by mining operations, as well as accumulated industrial waste utilization. The task of quickly determining the geo...

The research is aimed at identifying promising “quarry cavities – backfill material” systems on the territory of Ukraine. Currently, the existing reclamation methods for quarry cavities do not provide for the earth’s surface level complete restoration. A number of industrial wastes, the accumulation of which is increasing rapidly, are potential bac...

The paper describes topical issues of a prospective method for coalmine methane utilization for obtaining an additional valuable energy resource for the regional development of coal-mining areas. It is noted that the development of the extraction of methane resources is very urgent and is of great economic importance for ensuring the energy indepen...

Purpose. The research is aimed to identify, investigate and study the parameters and characteristics of the “quarry cavities – backfill material” systems on the territory of Ukraine using new comprehensive methodological tools that form the basis for the development of effective methods for restoring the earth’s surface with an emphasis on industri...

The paper draws attention to the ecological-economic aspects of mining thin coal seams in the strategic coal-mining region of the Western Donbas and studies their causes and consequences in detail. It has been analyzed and determined that as a result of coal mining with complete caving of rocks, the processes of the earth’s surface subsidence above...

The presented research focuses on the pressing issues of restoration of land areas disturbed by mining operations. The paper studies legislative peculiarities of industrial waste utilization for the purpose of reclamation of disturbed lands in Ukraine. Real practical examples of using low-hazard industrial waste for reclamation of land areas distur...

Due to the russian federation aggression against Ukraine, the infrastructure of many settlements has undergone significant destruction, so in the post-war period, limestone can become a reliable and useful resource for its reconstruction. A significant number of limestone deposits in southern Ukraine are suitable for the production of wall (block)...

В запропонованій роботі запропоновано комплексний підхід до вирішення проблеми проєктування багатопараметричних ресурсозберігаючих способів управління станом масиву гірських порід.

This paper is devoted to assessing the influence of waste rock surface dumps on the geomechanical state of underground mine workings. The conditions of the Pivdenno-Bilozerskyi high-grade iron ore field are chosen as the research object. To study the influence of dump placement and the depth of mine working on the mass stress state on the contour o...

Purpose. The objective of this study is to examine and compile a list of the most common types of backfill materials based on the analysis of successful backfilling practices in the development of technogenic cavities in mineral deposits in Ukraine. Methodology. The study employed theoretical analysis, information systematization, and data synthesi...

Purpose. To establish priority (control) factors affecting the probability of a sudden outburst of coal and gas in a breakage face, which will allow making optimal technological decisions when mining outburst-prone coal seams. Methods. An integrated method that involves the use of energy-force models to assess the likelihood of sudden outbursts of...

Purpose. The research purpose is to study the formation of quantitative-qualitative indicators of mined coal under conditions of dynamic changes in space and time with a new stope mining technology with waste rock accumulation in the underground mined-out area. Methods. The contours are formed for mining low-thickness coal reserves and extracting t...

Backfilling technology is not always used by mining enterprises, which is conditioned by technological and economic factors, such as the need for high mining rates and costs for the technological processes of transporting backfill materials from the daylight surface to the mined-out space. This concerns the underground mining of hard coal, which is...

Purpose. Development and generalisation of a set of key elements for a non-waste technology concept of mining high-quality coal from thin coal seams, based on the processes of backfilling the mined-out space with waste rocks from stope and tunnelling operations. Methods. A comprehensive methodical approach, containing the systematisation and genera...

Purpose. The research purpose is to analyze and generalize the problems of waste rock accumulation, as well as to determine the directions for their possible solution in order to improve the ecological-economic conditions for mining coal reserves in the Western Donbass. Methods. A comprehensive scientific-methodological approach is used, which cons...

Purpose. Development and generalization of a set of key elements for a non-waste technology concept of mining high-quality coal from thin coal seams, based on the processes of backfilling the mined-out space with waste rocks from stope and tunneling operations. Methods. A comprehensive methodical approach, containing the systematization and general...

Purpose. Determination of the granulometric characteristics and loosening coefficient of mine rocks formed during stope operations from undercutting the bottom rocks as a potential backfill material based on a set of mine and laboratory research. Methods. To do research, a complex methodology is used, which includes a photographic surveying the mas...

Purpose. Analytical study of the dissociation process of gas hydrates taking into account the peculiarities of phase transitions occurring during their dissociation and described by the Clausius-Clapeyron equation. Methods. The research uses an integrated approach, which includes the analysis and generalization of literature sources devoted to stud...

The paper presents the study of the deformation processes development in unstable rocks of the hanging wall during mining a thick steeply dipping ore deposit in the example of the Yuzhno-Belozerskyi deposit. In the studied field, there are problems of stability of hanging wall rocks, represented by low-resistant shale rocks that do not withstand si...

The paper focuses on mining hard-to-reach coal reserves, concentrated in the protecting pillars of main mine workings using auger technology. One of the Western Donbass coal enterprises - Pavlohradska Mine of PJSC DTEK Pavlohradvuhillia - is selected for the research, where in the conditions of С4 seam the use of the Auger machine BShK-2DM is consi...

Purpose. Analytical researches of the stress state of the backfilling stopes with different physical and mechanical properties using numerical modeling to determine possible zones of stability losses and predict their failure. Methods. Numerical modeling of the formation of stresses around a high stopes was carried out for the conditions of mining...

The study establishes the heterogeneity of the geological structure, properties of the ore deposit and rocks along the strike, which significantly affects the stability and probability of failure of the rock mass in the process of extracting ore reserves from the stopes. A comprehensive analysis of the geological structure of the Pivdenno-Bilozirsk...

Purpose. Theoretical and experimental research on the structural and strength peculiarities of the backfill mass formation during the ore deposits development by activating the binding material of the backfill mixture using fine grinding at the stage of its preparation. Methods. An integrated methodological approach is used, consisting of laborator...

Ukraine is an energy-dependent country, with less that 50% of its energy consumption fulfilled by its own resources. Natural gas is of paramount importance, especially for industry and society. Therefore, there is an urgent need to search for alternative and potential energy sources, such as gas hydrate deposits in the Black Sea, which can reduce t...

The present paper considers aspects of underground iron ore mining in Ukraine, in particular the level of mine production and reserves of basic ore fields. It analyzes and generalizes the practice of using cemented rockfill under difficult mining and hydrogeological conditions of the Pivdenno-Bilozerske high-grade iron ore field. The Belozersky iro...

The crystallization process of gas hydrates during their formation in the presence of surface-active substances (SAS) is studied. The research is conducted in two directions – theoretical and experimental. Experimental data on the crystallization rate of methane gas hydrates formation in the presence of surfactants have been obtained: high-molecula...

Purpose. Substantiation of the backfill massif parameters in fully mechanized selective mining thin coal seams, taking into account the influence of technological and mining-and-geological conditions. Methods. The integrated approach which includes the analysis and generalization of scientific developments in the field under study, analytical and n...

The problem of mining low-thickness coal seams in the Western Donbas is described in the article. Technological, economic and environmental reasons reducing the effectiveness of traditional technologies for their development are analyzed in detail and the new progressive approach is proposed to solve it. Attention is paid to the importance of hard...

The strength and microstructural properties of the backfill massif have been studied and assessed when filling underground cavities that pose a threat of mine rocks collapsing in the process of mining mineral deposits. It is suggested that due to a tendency to mechanical destruction by crushing Ca-O ionic bonds rather than Si-Î covalent ones, the b...

Purpose. Study the movement of waste rock flows in the coal mine technological system and determine the balance of rocks and underground cavities formation from the perspective of the current mining operations development in order to assess the possibility of leaving the rock in the underground area. Methods. Based on the rank order of the Western...

Based on experimental studies, the paper deals with the dynamics of the methane gas hydrates formation, influenced by the organized media, such as surface-active agents (surfactants, SAA), namely, dibutylphenol treated with ethylene oxide, as well as ethoxylated alcohols. The stalagmometric method with automatic photoelectronic drops counting, a co...

The article is dedicated to the technological peculiarities of natural gas hydrate deposits extraction with using perspective method which consists of introduction of carbon dioxide into the gas hydrate layer removing methane and creating CO 2 hydrate. Specific attention is paid to the insufficient efficiency of presently used methods in terms of t...

The need for a preliminary quantitative and qualitative assessment of coal seams to justify the feasibility of their use for selective mining with the placement cut rocks in the mined-out space is devoted in the article. The problem of mining thin and very thin coal seams (0.70–1.0 m) with cutting wall rocks, which leads to a deterioration the coal...

The peculiarities of the innovative approach to the utilization of coal mine methane, which is extracted by significant volumes due to the technological process of underground development of coal-gas fields, are revealed. An innovative energy-saving technology for producing gas hydrates with the maximum possible accumulation of alternative gas volu...

The actuality has been revealed of the necessity to attract the gas hydrate deposits of the Black Sea into industrial development as an alternative to traditional gas fields. This should be preceded by the identification and synthesis of geological and thermobaric peculiarities of their existence. It was noted that the gas hydrates formation occurs...

The research is aimed at revealing the theoretical features of the kinetics of the process of dissociation of natural gas hydrates, the accounting of which is useful in designing technologies for their development. The process of decomposition of gas hydrates is considered as a heterogeneous process, proceeding at the interface of the phases and co...

Розглянуто проблеми енергозабезпечення гірничопромислових регіонів України, що обумовлені суттєвою імпортозалежністю від природного газу, відсутністю ефективних технологій комплексного освоєння енергетичних ресурсів газовугільних родовищ і погіршеними соціально-економічним та екологічним станами гірничопромислових регіонів. Запропоновано перспектив...

This article is focused on solving the problem of power supply for the mining and industrial regions of Ukraine. This problem is caused by a significant import dependence on natural gas, the lack of efficient technologies in the integrated development of the energy resources of gas-coal deposits and the deterioration of social and economic, as well...

Purpose. Analysis of the man-made mineral formations of ore mining and smelting, fuel and energy complexes development accumulation, location and prospects amount in the Dnipropetrovsk region. Methods. Comprehensive approach, including analysis of state statistics, waste handling sites (WHSs), regional environmental report, environmental passport o...

The development of iron-ore deposits is accompanied by the excavation formation of considerable dimensions in the underground space and to ensure high technical and economic indicators of extraction, especially when developing high-grade iron ore, it is necessary to take into account the nature of the geological structure of the massif on the indic...

The relevant issues have been studied of ensuring the stability of producing wells in the place of their curving when uncovering the mining extracted area for the underground gas generator operation. It is emphasized that the design planning of efficient operation of underground gas generators in downhole gasification technology is impossible witho...

In this article, the mass and heat balance calculations of underground coal gasification process for thin coal seams in faulting zones of Lvivskyi coal basin are defined. The purpose of the research is to establish regularities of heat and mass balance changes in faulting zones influence due to usage air and oxygen-enriched blast. A comprehensive m...

Topical issues concerning the low efficiency of underground coal mining from thin and very thin seams as well as the problems of reserves left in mine fields by the closed-down enterprises resulting in substantial coal reserve losses have been highlighted. Alternative use of the unextracted energy resources is their physical and chemical transforma...

Purpose. Research of thermodynamic and geomechanical processes occurring in a gas hydrate body under the influence of an activating agent (sea water from surface layers) in the conditions of the Black Sea by mathematical modeling using finite element method. Methods. The modeling of thermodynamic and geomechanical processes is performed with the us...

Purpose. Justification of the effective dissociation process parameters of heterogeneous gas hydrate deposits and elaboration of their classification according to the thermal energy consumption. Methodology. The methodological basis of the conducted complex research is the analysis and synthesis of literary sources, devoted to studying the peculiar...

Coal is the main energy resource in Ukraine. However geotechnological aspects of coal seams development and Ukrainian crisis have a negative influence on the mining industry. This article analyzes the experience in the development of very low and low-coal seams with 0.7–1.0 m thickness, as well as advanced technological solutions that allowed priva...

In this paper, the geological faults in the zone of stable geodynamic and tectonic activity are studied. The purpose of the analytical research is to establish regularities of rock pressure in the hanging and foot walls of the geological fault and its influence on the state-deformed state of the rock massif. Comprehensive methodology that included...

This study addresses the production of gas hydrate of methane with a high gas-hydrate-forming content in a solid phase in the isolated system at T=274 K and pressure of 5 MPa and presence of mechanically activated rocks close to the bottom of the chamber. We used mechanically activated samples of various degrees of grinding to increase an area of c...

One of the most perspective non-traditional sources of hydrocarbon raw materials and energy is gas hydrates (GH), which stimulates their large-scale study in many laboratories and scientific centers around the world. The interest in the GH is related to the possibility of their industrial application. The use of technologies for storage and transpo...

Purpose. Determination of economic efficiency of gas hydrates deposits development of heterogeneous structure based on established technological parameters of their decomposition for increase the investment attractiveness of additional gas resources extraction from the Black Sea. Methods. To achieve this purpose, analytical calculations of economi...

The process of hydrate formation of methane in the presence of SAS in the temperature range of 274‒281 K was examined. The aim of the research conducted was to establish the effect of SAS on the process of GH formation, as well as to study kinetic features of their formation in the three-phase system “gas”‒”water+SAS”→”solid body (GH)”. We applied...

Mining of coal deposits nowadays in Ukraine has to include not only coal extraction but following processes that accompany coal extraction. In the article, the potential of biomass usage for additional heat and power generation during coal seam gasification is proposed. The innovative technologies in mining such borehole underground coal gasificati...

Mining of coal deposits nowadays in Ukraine has to include not only coal extraction but following processes that accompany coal extraction. In the article the potential of biomass usage for additional heat and power generation during coal seam gasification is proposed. The innovative technologies in mining such borehole underground coal gasificatio...

The results of the gas hydrates formation process research are received using various porous media. A series of laboratory experiments directed to receiving gas hydrates samples in climate regulation chamber KTK-3000 is conducted. The change of parameters of gas hydrates formation process at rock sand presence as porous medium is established.

Given work presents urgency of the alternative sources of energy development, in particular, gas hydrates. Evaluation is given to the Black sea's gas hydrates amount and volume of methane in them. Also gas hydrates formation conditions are scrutinized. Leading technologies of gas recovery from gas hydrates are considered. Special attention is paid...