Dust dispersion in a coal roadway driven by a hybrid ventilation system: A numerical study

Dust contamination to ventilation systems is a common issue for mine operators during underground coal mining. In the present study, dust dispersion driven by a hybrid ventilation system in an underground mine has been investigated via a computational fluid dynamics (CFD) model. Specifically, the numerical model was developed based on the Euler-Lagrange method where the trajectory of dispersed dusts was solved individually. Dust dispersion induced by turbulence was considered by a stochastic tracking model. Effects of key parameters (e.g., gas velocity and exhaust duct length) on dust dispersion characteristics throughout the coal roadway have been examined. The results showed that the distribution of dusts exhibited extreme non-uniformity with a significantly higher concentration present near the mining face, particularly on the exhaust side. The cross-sectional average dust concentration substantially decreased along the axial direction in the front part of the coal roadway. Intense circumfluence and secondary sedimentation of dusts were found to be the main mechanisms that drove the non-uniform distribution of dusts. The model is shown to be capable of reproducing the dust dispersion process captured in the experiments and the prediction results agree well with the experimental data. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.