화학공학소재연구정보센터
Process Safety and Environmental Protection, Vol.102, 734-756, 2016
Mining-induced void distribution and application in the hydro-thermal investigation and control of an underground coal fire: A case study
Mining-induced voids are a necessary factor triggering underground coal fires that endanger the underground and atmospheric environment. On the other hand, voids provide channels for underground fluid and fire-fighting material migration. A series of void rate models were proposed to determine the three-dimensional heterogeneous distribution of the mining induced voids in the disturbed strata. The void rate distribution map of horizontal voids presents a reversed "quadripod-type" shape in the strata plane, the void rate of vertical voids has a shape similar to two "basins" of different sizes and contrasting opening directions nested together, and the void rate of isotropic pores presents a "basin-type". It can be deduced from the distribution maps that were calculated by theoretical and numerical models that the voids present a "fractured dome" distribution and that the void rate gradually decreases from foot to crown of the dome. It was ascertained from the application of void rate models in the hydro-thermal investigation of an underground coal fire that the correlation between heat production and ground surface temperature presents a linear function, while that between outflow velocity and fire source temperature has a negative-exponential power relationship. Additionally, a new Plan-Do-Check-Adjust cycle was established for the management of fire-fighting engineering, which includes the delineation of fire zones, the evaluation of fire behavior, the optimization of fire-fighting measures, the performance of the fire-fighting plan, and the assessment of control results to determine whether the fire-fighting plan should be reformulated or improved. After five control cycles lasting nine months, an approximately 115,200 m(2) fire zone was controlled. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.