Theoretical and geotechnological fundamentals for the development of natural and man-made resources of coal deposits

Purpose. Theoretical and technological substantiation of parameters and schemes related to formation and use of natural and man-made volumetric and thermal resources of abandoned coal deposits using complex of geo-modules providing their activation, selection and storage in keeping with uneven seasonal energy consumption. Methods. Analytical and numerical methods for solving equations of hydrogas dynamics and heat- mass transfer; mathematical modeling by means of special software; statistical methods; stabilometrical testing of aqueous rocks samples by triaxial compression tool. Findings. The system of models presenting gas-dynamic, filtration and heat processes occurring in disturbed rocks as a result of natural and man-made resources development while shutting down mining works has been developed. The studied patterns of water and gases movement in low-permeable coal-bearing rocks, reservoir beds and flooded mines allowed to evaluate the technological parameters of extraction, accumulation, and utilization of these heat transfer fluids for heating and cooling of buildings. The paper proposes and justifies technological options serving to utilize the thermal resource of water in a flooded mine and to activate this resource by underground combustion of residual coal reserves. Originality. The mechanism of heat transfer in the flooded rock mass of the abandoned mine with periodic pumping and selection of mine waters from different horizons and their heating by natural geothermal heat and underground combustion of residual coal reserves has been studied. Practical implications. The developed models have been implemented in real mines which allowed to evaluate the ranges of flow and heat transfer parameters related to the conditions for heat transfer fluid extraction and utilization at the final stage of mining. The developed models and obtained dependences allowed to justify the parameters of technological schemata aimed at the development of natural and man-made resources of coal deposits