Khramov V. Geological criteria of non-conditioning coalbed productibility for underground gasification (on the pattern of the Lviv-Volyn coal basin).

Dissertation is devoted to substantiation and study of complex geological criteria for Lviv-Volyn basin (LVB) adhering of which gives a chance for commercial development non-conditioned seams (ncs) using the technologies of underground coal gasification (UCG): Minimum thickness of coal seams suitable for underground gasification is estimated to be 0.2 m, the upper limit is conditionally accepted as 0.5 m due to impossibility of the mine mode of development. 22 sketch maps of the thickness distribution of ncs from the Tygliv field were compiled as well as their typification was carried out by the availability of areas with thickness of the given interval. UCG-area is a part of the coal seam without disturbance of its wholeness because of impossibility of the well's connection and unexpected losses of extracted gas. Localization of UCG-areas comes to regional and local distinguished of structural-tectonic blocks of different order. Total water amount in a zone of reaction determines the composition of synthesized gas (predominance of CO + H2 or CO2 + CH4). Those seams in which the amount is over 1 kg per 1 kg of water due to endothermic reaction effect are impossible to be gasified. Isolation of the UCG-areas is provided by impenetrable rocks of the cover and the basement. Predominance of argillites, aleurolites, and limestones was proved in enclosing rocks, and the regularities of the main lithological varieties of the cover and the basement of the localized UCG-areas of the Bashkirian stage of the Tygliv-1 mine field were studied. Melting temperature of the mineral components of coal ash and enclosing rocks must be less than the temperature of reaction to prevent corking of communicating channels and coal covering.