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The paper represents the studies of the process of carbonaceous raw material gasification. The initial material is represented by bituminous coal of grade H with the carbon (C) content of 79.2-85.3 %. Experimental studies have been used to substantiate the parameters of combustible generator gases (СО, Н2, СН4) output depending on the temperature of a reduction zone of the reaction channel and gas flow velocity along its length. It has been identified that the volume of the raw material input to be used for gasification process changes in direct proportion depending on the amount of burnt-out carbon and blow velocity. The gasification is intensified in terms of equal concentration of oxygen and carbon in the reaction channel of an underground gas generator. The gasification rate is stipulated by the intensity of chemical reactions, which depend immediately on the modes of blow mixture supply. Moreover, they depend directly on the intensity of oxygen supply to the coal mass and removal of the gasification products.

Results of evaluating the suitability of certain sections of Western Donbas coal seams, based predominately on properties of coal material, for their further experimental development by means of underground gasification method are represented. Criteria to evaluate both expediency of underground gasification and specific conditions of that process are substantiated basing upon the methodology developed at the National Mining University (Dnipro, Ukraine) together with representatives from National University of Saint Augustine (Arequipa, Peru). The methodology has been industrially approved with the confirmation of its efficiency while developing technical documentation for underground gasification projects: “Project of experimental section of Pidzemgaz station of Pavlogradvuhillia association”, “Feasibility study of the expediency of the construction of Pidzemgaz station” FS 3858-PZ”, Synelnykovo deposit; “Project on experimental underground gas generator”, Monastyryshche deposit, FS of experimental module of UCG station of Solenovske coal-mining area, Donbas. Also, they contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.

The purpose of this study was to develop a physico-mathematical model and technique for estimation of chemical bond stability depending on electric field intensity of an external point charge. A hypothesis for a possible physico-chemical mechanism of the formation of additional harmful gases in the rock destruction by blasting was proposed. The theoretical basis of the hypothesis is the method of theretical evaluation of bond energy depending on the distance to a point charge, the third Coulomb centre. The quantum-mechanical model for calculating the electronic terms of molecules makes it possible to solve problems associated with the determination of parameters of molecules under the action of various physical fields on the system under consideration. The model was approved for some diatomic molecules. The discrepancy between the experimental data and calculated data did not exceed 14%, which proves accuracy of the obtained results. The model can be used in the field of research into the causes of gas-dynamic phenomena in underground coal mines, in studies of the degree of stability of nanostructured components of coal under physical influences, and in the theoretical design of new compounds and structures in the field of nanomaterial science and nanotechnology.

This article is a summarizing of the results of the author's team on the establishment of technological parameters of underground gasification. It provides a justification of the final chemical and energy products that can be obtained as a result of complex physical and chemical transformations of coal. The thermodynamic processes of formation of the gasification source when changing the composition of the blast furnace mixture and the modes of its application to the georeactor are considered. Moreover, the change in the stress-strain state of rocks depending on the composition of the lateral rocks is taken into account. To better ensure the results are consistent with the well-known principles of thermodynamics and phase formation under the influence of the temperature field and the main chemical reactions occurring in complex gasification processes are presented. The main phase transitions in the georeactor are given for the maximum reception of different energy gases. Particular attention is given to the formation of an appropriate relationship between hydrogen and carbon monoxide, which form a synthesis gas. The Anderson-Schultz-Flory reaction is used to determine the maximum CO concentration in the outlet mixture. In general, the system for determining the material and thermal balance is proposed. These approaches were checked both for working out the coal reserves and for utilization of the mining waste products. Results of this investigation were included to the Roman Dychkovskyi thesis of the scientific degree of the Doctor of the Technique Sciences “Scientific Principles of Technologies Combination for Coal Mining in Weakly Metamorphoses Rockmass”. Also, this results were partially presented on international scientific and practical conferences “Forum of Miners” from different years. They contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.

The authors of the paper consider the concept of further prospective development of mining enterprises. The basis of this concept are scientific results obtained during the study of physical and chemical processes of solids conversion into the gaseous state: coal → gaseous fuels. It was established that the main base of development of mining regions is a mining power-chemical complex. The basic segment of which is a well underground coal gasification station. It is established that increase of indicators of efficient operation of the station from gasification is possible by synthesis of technical and technological decisions on the use of coal seam energy. When coal gasification is over, the gasifier passes into a mode of thermal generator with the use of alothermal technique to remove heat and thermic decomposition products from the degassed space of the gasifier. Generator gas at its initial temperature (1100 – 1300oС) around an underground gasifier creates a powerful heat boiler with a temperature regime of 200 – 300oС. It was established that at work of six gasifiers on a coal seam with thickness of 1.0 m with geometrical parameters each at a width of 30 m and at the length of 450 m energy-thermal power will be 237.8 MW. At the same time, additional energy resources can be obtained by involving segments of alternative forms of energy supply to the life cycle of the mining enterprise.

Results of computer modeling of stress-deformed state of rock massif with the use of software FLAC 5.00 in zones of geological fault influence with amplitude that does not exceed 3m are presented in the article. According to the results of the modeling, the dependences of vertical stress change in handing wall and foot wall of geological fault with variable fault plane amplitudes and contour well deformation have been obtained. Using the interpolation data method, 3-D grid visualization of vertical stress in space is got. The analysis of modeling results on full movement vectors is also presented. Results of previously conducted analytical calculations are compared with received data. Conclusions regarding the implementation of the offered method are made on the basis of undertaken investigations.

The formation of the stress-strain state of rocks in the several phase gasification processes was considered. Proceeding from the well-known principles of thermodynamics and phase formation of the multi-type rockmass under the influence of the temperature field, a geomechanical model of a two-layer artificially-formed shell formed during the gasification process by the method of variation feeding of the blowing mixture to the body of the gas generator was developed. The Neumann principle is used for the magnitude determination of the maximum stress vector, which involves the definition of the axial tensor of mechanical deformations through the anisotropy of the thermal expansion (the polar tensor of the second rank). This makes the possibility to create the base for a package of information programs creation. Such programs give the possibility to simplify the study of the rockmass deformation characteristics and to evaluate the stresses in a thermally changing environment. Researches are carried out by creating the final element system with the adaptation to the specific mining-geological conditions. These approaches are checked both for working out the coal reserves and for utilization of the mining waste products. Results of this investigation were included to the Roman Dychkovskyi thesis of the scientific degree of the Doctor of the Technique Sciences “Scientific Principles of Technologies Combination for Coal Mining in Weakly Metamorphoses Rockmass”. They contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.

Energy efficiency of coal gasification with possible utilization of mining wastes within ecologically closed gas generator cycle has been considered. Technical and technological performance of such gas generator and mechanism of material and heat balance on the basis of the available analytical methods and practices as well as the developed author software have been proposed. Heat carrier formed in the process of coal gasification has been used for the utilization. Temperature of the utilization process within the industrially expedient limits being supported with the help of either activation or attenuation of the gasification process. After specific treatment, organogenic waste and domestic wastes are utilized by means of thermal decomposition within a gas generator. Economic evaluation of the proposed means confirms the expediency of their implementation in mines with industrial and balanced coal reserves as well as within the areas where this energetic source has already been already mined out. Results of this investigation were partially presented on international scientific and practical conference “Forum of Miners - 2017”. They contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.

The method of investment attraction evaluation for the implementation of mining equipment was substantiated. Discounted financial results were taking into account. Pros and cons of chosen method were analyzed. The practical results of the method for definite technical and technology conditions at the SC “Lvivvuhillia” were presented. Values of investment attractiveness taking account monthly costs were determined. The methodology which was worked out by UNIDO were used for conditions of mining equipment implementation for coal reserves exploration of extraction area of mine taking into account cash flow values at the different periods of project realization. It was definite that chosen methodology gave possibility to estimate projects investment attractiveness and could be used for similar projects at the other mining enterprises.