Abstract: 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.
Abstract: This study shows the influence of calcinations temperature and particle size of natural garnet mineral on its hardness and abrasiveness (H/A) for use in water jet cutting of tough materials. A standard commercial sample of the mineral was characterized in terms of the hardness and abrasiveness properties. The sample was sized to 4 fractions having the size of <60 um, > 60 < 100 um, > 100 < 200 um and > 200 < 250 um designated the symbols, FF, MF, MC and C respectively. Each fraction was separately heated in controlled conditions at temperatures up to 1000°C at a heating rate of 10°C/min in an electrically heated tube furnace. Soaking time at the maximum temperature was 60 minutes. Hardness and abrasiveness properties of the heat treated samples were tested to cut marble having a thickness of 30 mm. Results revealed that H/A of the garnet mineral increased by heating at temperatures up to 750°C and exhibited gradual decrease with higher temperatures up to 1000°C. Results were explained in the light of a structural irreversible metamorphism (SM) of the garnet crystals; almandine Fe2 + 3Al2Si3O12 and propel Mg3Al2Si3O12. Metamorphism involved reorientation of the crystals followed by coherence to form dense grouping. At higher temperature, irreversible thermal expansion of the structure sets in. Characterization of the mineral was carried out with the help of XRD, SEM and FT-IR measurements.
Abstract: The concept and a new method for the shielded development of bottom gas hydrates have been proposed, the technological phases and constructive elements of their implementation have been substantiated. The research provides for the realization of the idea suggesting the simultaneous dissociation of the vast areas of a gas hydrate deposit, management of the targeted process of the penetration of methane recovered from gas hydrates into water space and its accumulation under the extensive gas-collecting shield wherefrom it is removed by bottom pipe transportation facilities. To do hydraulic fracturing, a well is drilled into the plane of the junction of the surface of a gas hydrate deposit and the rocks of a roof, the open system of fissures in the rocks of a roof is made through which produced gas is released to a gas-collecting blanket in a water.
Abstract: The physicomathematical conjugation of filtration models of a flooded and an adjacent mine is carried out with a justification of methodological principles of analysis and prediction of a technogenic mode of groundwater in conditions of operation and flooding of a mine field. The identity of models and real objects is established as a result of solving a series of inverse problems and is confirmed by a water balance discrepancy of 0.003%, the convergence of water inflows in separate layers with a deviation of 5 – 12.5% and the coincidence of groundwater surface levels on models and data of a mode network. According to results of predictive solutions, it is established that dynamics of flooding of a rock massif within old stopes are more intensive than the restoration of a level of groundwater in a mine shaft. The options of technical solutions for curtailment of mining operations are justified, the ecological risks and costs of which can be optimized by constructing a water intake of technical (or drinking) water in the productive stratum of riverbed sandstones, as well as equipment for geocirculation heat supply systems using the capacitive resource of a flooded mine field.
Abstract: Results of theoretical, laboratory and stand study which enabled to recommend solutions of surface active substances while well drilling, taking into account mining and geological conditions of a number of Ukrainian regions are given. It was determined that addition of surface active substances to the drilling fluid during rotary drilling by hard-face and diamond cores makes it possible to increase drilling rate.
Abstract: The paper is devoted to the issues of energy saving automatic control of radial burden distribution in the blast furnace throat. The main idea consists in control with prediction of the control resulting on the basis of automatic monitoring of burden surface texture. The paper develops the mathematic description of burden surface texture on the blast furnace throat by means of substantiation of minimum quantity of general indicators of the mixture being closely related to the main parameters of blast furnace processes. It is the first time that the optimum value of hoper depth in burden surface at 0.14 – 0.2 of throat diameter determined, the methods of its stabilization at the rate are substantiated, the new regularity of burden surface formation on the operating blast furnace throat is shown as consisting in the fact that the hoper depth on the surface is mainly changed responding the process of material charge rather than bulk material descent after the charge. It was also substantiated for the first time that radioisotopic methods for current control of burden distribution on the blast furnace throat provide timely formation of control actions for gas flow stabilization. The principle of self-tuning was theoretically substantiated for monitoring system of gamma profilometer responding to the monitoring conditions with respect to high penetration and random character of gamma rays. The principle enables significant improvement of accuracy, quick-response and radiological safety of gamma profilometer operation. The possibility of determination of burden surface texture on the throat of operating blast furnace and distribution of burden components according to infrared radiation of the surface without application of radiation hazardous monitoring means was proved for the first time.
Abstract: 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 (Ukraine) 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 methodology that included analytical calculations is implemented in the work. The output parameters of coal gasification products for the Lvivvyhillia coal mines are detailed. The heat balance is performed on the basis of the mass balance of underground coal gasification analytical results and is described in detail. Interpretations based on the conducted research and investigation are also presented. Conclusions regarding the implementation of the offered method are made on the basis of undertaken investigations. According to conducted research the technology of underground coal gasification can be carry out in the faulting zone of stable geodynamic and tectonic activity. The obtained results with sufficient accuracy in practical application will allow consume coal reserves in the faulting zones using environmentally friendly conversion technology to obtain power and chemical generator gas, chemicals and heat.
Abstract: Amber of amber-bearing deposits in Rivne-Volyn region of Ukraine has been analyzed. Relying upon instrumental techniques, physical and chemical as well as spectral analyses, and geological prospecting of the deposits, chemical composition and ultimate composition of amber occurring at the territory of Klesiv deposit (Ukraine, Rivne Region, Sarny District) have been identified. Klesiv amber contains the greatest part of inclusions; it contains 18 chemical elements. Basing upon the performed geological cross-section it has been determined that the amber occur in sandy soil and sandy-shale soil. The depth is insignificant – from 1 m to 10 – 15 m. Moreover, to determine the cost, experimental technique has been developed. The technique involves classification of the amber fragments according to their form, dimensions, and colour. Lithologic-and-facies sections of sites of Klesiv deposit have been obtained.
Abstract: This paper justifies the use of the mobile crushing-and-sorting radiometric complexes (MCSRC) under conditions of iron-ore pits in order to increase the ore quality produced in the mine faces of the «ore-rock» contact zone and stabilize the content of the useful component in the general ore-flow. The patterns, which are used as a fundamental base of the radiometric sorting process, are given. The functional scheme of MCSRC is considered, the algorithm of operation is developed, and the main technological tasks of the complex are determined. The technological scheme of the face sloping using MCSRC and formation of the all-pit ore-flow is developed. The expected indicators from use of the mobile crushing-and-sorting radiometric complex in the form of the technological, economical, power-saving and ecological effect were considered.