Purpose is to substantiate and develop an efficient scheme of coalmine methane capture while preparing and developing gassy coal seams. Methods. Critical analysis of literature sources has been carried out; practice of applying the known schemes of coalmine methane capture for its further use has been systematized. Analysis and selection of theoretical substantiation of a new coalmine methane capture scheme have been performed taking into consideration the parameters of preparation and development of gassy coal seams. Methods of mathematical analysis have been applied to describe the dependence of gamma distribution of the continuous random variable of gas emission intensity on the distance to a stope. Findings. A scheme of coal mass degassing has been improved; that scheme helps increase degassing degree and eliminate colliery gas, including methane, in terms of specific arrangement of wells and introduction of new technological operations and parameters. The developed scheme takes into consideration physical and mathematical properties of rocks to increase the volume of produced gas along with the reduced total mining costs. Mathematical modeling has made it possible to define that the density function coincides maximally with the experimental and practical graph of dependence of gas emission intensity on the distance to a stope. Originality. Analytical dependences have been specified making it possible to evaluate rational range of the depth of degassing gas outlet wells and the distance between them according to the proposed scheme of their arrangement within the extraction pillar. Practical implications. The proposed scheme of coal mass degassing allows controlling coalmine methane extraction including special preparatory operations. It helps widen a range of effective application of the system for colliery gas extraction and reduce the time for preparatory degassing operations; that favours both rising stope output and the associated coalmine methane recovery with the corresponding increase in energy saving and safety during mining operations.

The problem of development of gas hydrate deposits is complicated by a range of problems connected with the adaptation of traditional methods and procedures to develop the mentioned type of raw materials. Construction methods of the directed well deserve high attention since they are the most efficient solution to provide a stable process of gas fraction production. Experts of the Dnipro University of Technology are at the top among the studies engaged in implementation and operation of gas hydrate deposits. Among other things, the experts have designed rational bottomhole assemblies of the directed drilling for the conditions of gas hydrate deposits. Such devices have a number of functional features. The paper describes following particularities being the most significant ones: a material to produce destructive balls and their physical properties; operating modes of a drilling process; directionality of bottomhole circulation processes as for the operational parameters of flushing fluids; and spatial location of well direction. Both calculations and bench tests favoured the process intended to identify functional features of the devices and proved convincingly the truthfulness of the initial theoretical foundations to drill the directed wells with the help of the modernized hydromechanical boring tool combined with a feeding device. The paper purpose is to analyze and substantiate structural solutions within the certain units of techniques for complex use as well as determine the rational operating schedules of the latter in the context of specific geological conditions where the directed wells are under construction.

Objective of the paper is to substantiate rational ore-stoping technique while using small wells in the context of thin-vein steeply inclined deposit mining. The technique is based upon the repeated field studies and simulation of ore drawing processes for shrinkage ore stoping in terms of the oriented drilling of periphery holes. A design of a blast-hole charge with low-density porous intermediate layer has been proposed as a result as well as a mechanism of shock-wave propagation within rock mass in the process of thin steeply inclined vein stoping. Scientific novelty is represented by means of analytical results of scientific sources, and dependences of ore losses on the vein wall hypsometry resulting from shrinkage stoping in the context of the technique being proposed. Practical relevance is to substantiate rational parameters of the ore-stoping technique being proposed. The technique involves designs of blast-hole charges with low-density porous intermediate layer in stemming. Moreover, the technique proposes to place the intermediate low-density stemming layer right after a blast hole was charged with explosives and live primers were inserted.

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Usually, basic traffic flows of mining enterprises are effected with the help of transportation vehicles with a flexible tractive element, i.e. belt conveyor, ground ropeway etc. Parameters of transport and operation procedures depend upon mining and geological conditions of mineral mining, technical characteristics, and operation parameters of the transportation vehicles. Objective is to substantiate a new equation of friction of flexible bodies which corresponds to classical concepts of friction of bodies. The methods are based upon the adjustment of common idea of friction of bodies; factors, working upon friction; and solutions of Euler problem on flexible body slip along the fixed block. As a result, common factors of friction of inflexible bodies, i.e. friction force and normal reaction between linearly connected bodies, have been determined; new equation of friction of flexible bodies has been substantiated. Scientific novelty has been represented by means of a new equation of friction of flexible bodies (in the indirect form) which: involves friction force and normal reaction between linearly connected bodies; corresponds to equilibrium conditions of a mechanical system; and coincides with friction law of Coulomb bodies being common one. Practical implication is in the proposed new scientific knowledge giving corrected idea of friction of flexible bodies. The knowledge improves both education level and research level stipulating technological expansion as well as upgrade of transportation vehicles with flexible body. The findings can be applied to improve both efficiency and safety of transportation vehicles with a flexible tractive element under complicated operation conditions; among other things, it concerns mining enterprises.