Dust transport law and ventilation parameters optimization in heading face under long-pressure and short-pumping ventilation conditions

The working face of underground mining is the most complicated place regarding wind flow distribution and dust transportation and the most challenging place regarding dust prevention and control. Therefore, minimizing the dust concentration in the working face has become the key to efficiently mining deep coal resources. Long-pressure and short-pumping ventilation is widely used in long-distance heading faces. However, there are fewer studies on optimizing ventilation parameters for the actual situation on site, and the ventilation effect still needs to be improved. To solve this problem, this study took the 2–2 upper coal face of Xinjie Taigemiao mine as the research object, combined the Euler–Lagrange method and discrete-phase model for numerical simulation, and investigated the influence of the position of the windpipe opening and the pressurized opening, the ventilation volume, and the ratio of the pressure and extraction on the effect of the ventilation and dust removal, which revealed the distribution of the wind flow and the law of dust transport in the heading face under different working conditions. Finally, the optimal combination of the ventilation parameters was established. The results show that the tunnel's dust concentration distribution exhibits the traits of three zones. The ideal ventilation parameters include that in the effective suction range of the extracting windpipe, the distance between the extraction air outlet and the heading face should be appropriate to increase, recommended Lc = 5 m; the pressure tube should be located in the influential suction range boundary position, recommended Ly = 24 m; ventilation should be appropriately reduced, recommended Qy = 200 m3/min; and maintain the pressure–extraction ratio is greater than 1, recommended K = 1.2. The research results provide reliable ideas for dust management during deep coal seam mining.