Purpose. Substantiation of the mechanism of loading the preparatory mine working support to optimize its deformation-strength characteristics based on the calculation of the stress-strain state of the "massif -support" system. Improving the cost effective technologies for fastening and maintaining the preparatory mine workings.Methods. The analysis of the elements interaction modes of the "massif -support" system has been performed by the two-parameter diagram for optimizing the deformation-strength characteristics of the rock massif and the preparatory mine workings support using the research results of the stress-strain state of a system by means of finite element method. A comparison has been made of computational experiment with mine instrumental observations.Findings. The geomechanical model of the computational experiment on the choice of operation modes of the fastening system, as well as the methodology of the approach to optimize the process of interaction between the massif and the support have been substantiated. The analysis of search patterns for the rational deformation-strength characteristics of the fastening system in the preparatory mine working, taking into account the influence of the main geomechanics factors on this process, has been developed and performed.Originality. The patterns have been established of the geomechanics factors influence on the choice of rational operation modes of the load-bearing elements of the fastening system and the support in general based on research of the stress-strain state of the "massif -support" system. The optimization principles of interaction based on the analysis of a two-parameter interaction diagram have been substantiated.Practical implications. The wide perspective has been substantiated for strengthening the soft rocks in reusable preparatory mine workings with combined roof-bolting systems, which makes possible to realise the resource-saving conditions of maintenance. The calculations have been made with account of the optimization criteria for interaction of massif and support.

Purpose. Substantiation of conceptual base of searching the ways of threats prevention to sustainable development of coal enterprises in the presence of multidirectional vectors of economic pressure of the external environment.Methods. Methods of the structural and comparative analysis for an assessment of usage of the main definitions of a research, their essence and communication with other categories which define efficiency of development of the coal enterprise are used for the solution of the set tasks in the work; groups and classifications are used for systematization of types of economic security and stability of the enterprise, and also factors which cause them.Findings. The analysis of main definitions that reflecting essence of such scientific phenomena as "sustainable development" and "economic security" of the enterprise is conducted. Actuality and reasonability of scientific research conducting on formation of methodical base and tools of an assessment of a technological component of sustainable development safety of coal enterprises is substantiated.Originality. Research of opportunities of the comprehensive programs creation of adaptive management of the mining enterprise including a retrospective and perspective assessment of a pathway of its development.Practical implications. Introduction of adaptation activity at the coal enterprises in aspect of process of technological safety ensuring.

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The augering mining of thin and very thin coal seams has been proposed for using the efficiency of this task, related to the stability of reusable mine workings. The interrelation has been established and optimized between the support loading parameters in the extraction working during the augering mining of thin and very thin coal seams with the stress-strain characteristics of the protective monolithic strip of variable rigidity. The strength properties of sand-cement stone for the erection of rigid and yieldable parts of the protective strip are studied. The regression equations are obtained, which allow to determine the rational force, deformation and geometric parameters of the “support – protective strip” system elements during the extraction workings maintenance.

Purpose. The research purpose is to develop a concept for complex mining of mineral resources from coal mines using the example of PJSC DTEK Pavlohradvuhillia mines with a transition to multi-product production of clean drinking water, utilization of methane, secondary coal from rock dumps and sludge reservoirs, low-potential thermal energy of mine groundwaters and associated raw materials from desalination waste. Methods. The research uses an integrated approach, which includes an analysis of existing experience and available complex coal mining technologies, laboratory studies of mine water desalination technology by the reverse osmosis method with thermal distillation of concentrated brine, and chemical analysis using ElvaX laboratory equipment. Findings. This paper presents the research results of a comprehensive analysis of mineral raw material resources related to coal mining. The technically achievable energy potential that can be produced from the secondary coal of rock dumps and sludge reservoirs has been determined, which in total is 183.3 TJ. The annual heat potential of methane gas utilization has been estimated, which in total of PJSC DTEK Pavlohradvuhillia’s mines reaches 7.1 PJ. The possibility of extracting up to 1.12 TJ/year of associated thermal energy from the water-drainage installation of mine complexes has been determined. For the conditions of the Zakhidno-Donbaska mine, the authors of the paper have developed a technological scheme for the water preparation process by the reverse osmosis with the desalination brine treatment by the method of multistage evaporation on adiabatic evaporators. Originality. For the first time, the energy flows related to coal mining technology have been comprehensively analyzed for the possibility of their joint use to cover the needs of the mine complex. The prospects for complex mining of mineral resources have been assessed based on the adaptation of the mine complex production facilities to the multi-product production of clean drinking water, utilization of methane gas, low-potential thermal energy from mine groundwaters and secondary raw materials of desalination waste. Practical implications. The proposed set of technological solutions will ensure the sustainable development and diversification of the production of PJSC DTEK Pavlohradvuhillia coal-mining enterprises, as well as the effective transformation of coal-mining cities during the period of transition from mono-product production to the creation of multi-business production complexes that comply with ESG principles. The creation of multi-product mine complexes capable of producing not only coal, but also heat and associated mineral raw material resources, should become a guarantee of stable social-economic development of coal-mining regions.