Study on spray dust removal law for cleaner production at fully mechanized mining face with large mining height

Aiming at the problem that it is difficult to control high dust hazard in fully mechanized mining face with large mining height, an airflow-droplet coupled model was established based on the Euler-Lagrange method. Through a custom-developed nozzles atomization experimental system, main parameters were measured, and the builtin butterfly division core nozzle with an aperture of 1.6 mm was selected. The simulation results showed that the range of 1(#) similar to 3(#) hydraulic supports on the leeward side of the coal cutter was the best area to prevent dust from spreading to the sidewalk. The spray scheme of four groups of hydraulic supports was used, and each group had six nozzles. The vertical-horizontal combined dispersion scheme and 30 degrees spray scheme were adopted. Besides, the distribution law of average size and concentration of droplets was revealed. After field application, the dust-reduction efficiency of the optimal scheme was 38.3% higher than that of the original scheme. (C) 2021 Elsevier B.V. All rights reserved.