Mechanism of development of coal dust continuous explosion in a network of mine workings

Abstract

The objective of this paper is to reveal the mechanism of creating conditions for the continuous explosion of coal dust by transferring seismic energy to coal dust located along the perimeter of a working. The ANSYS software package was used to model the movement of coal dust particles in the air under the influence of seismic waves caused by the action of an explosion. It was confirmed by modelling that seismic waves, provoked by an explosion, propagate in the rock mass at a higher velocity than the moving explosive front in the air of a working. The qualitative and quantitative behaviour of a layer of coal dust in the process of oscillation of the working walls under the influence of seismic waves during one second was described. The stage of dynamic loosening of the powder is supplemented by the initial period of the mechanism of explosion development, when there are no combustible concentrations of gas or coal traces in the air composition of the mine working before the incident. It is established that under the seismic influence at a distance of about 50 m from the hypocentre of the explosion, a layer of powder-like dispersed coal rises into the air forming a dust cloud, which is the initiator of further continuous development of the explosion spreading in a network of mine workings.

Use of solid mining waste to improve water retention capacity of loamy soils

“…The key to energy security and energy independence of Ukraine is the stable functioning of its own fuel-energy sector, the main component of which is the coal industry [1], [2]. Underground mining of energy resources is characterized not only by difficult mining conditions and technological processes with constant exposure to hazardous factors [3], [4], but also by a significant technogenic burden on the environment, due to the generation of waste of various aggregate states [5].…”

Substantiating the Parameters of Quickly Erected Explosion-Proof Stopping

“…According to the State Paramilitary Mine Rescue Service in the Coal Industry (SPMRS), the annual number of underground fires in 2014-2019 ranged from two to six. In 2015-2017, the frequency of explosions of methane-air mixture (the number of explosions per 1 million tons of coal) increased from 0.025 to 0.08 (2015: 1 explosion per 21 million tons of coal; 2017: 1 explosion per 12.5 million tons of extracted coal) (Kostenko et al, 2022;Zavialova et al, 2021). The main part of the time spent on fire and explosion suppression is from 200 to 1,100 hours, which is 50 to 60% of the total time loss of SPMRS.…”