Design and Optimization of a Dust Suppression System in a Comprehensive Mining Face

Fully mechanized coal mining is a key method of coal extraction. As mining intensity increases, dust pollution in fully mechanized mining faces has become increasingly severe, significantly hindering the coal industry‘s alignment with the “Healthy China” strategy. To address the prominent dust pollution and the inefficiency of current spray dust suppression methods, this study proposes a combined spray dust suppression system. Using the Taigemiao mining area—where the coal dust exhibits hydrophilic characteristics—as a case study, we investigate the system’s spray flow field characteristics via numerical simulation. The results indicate that activating the shearer‘s external nozzles increases the airflow velocity near the shearer to 4 m/s, with the droplet concentration at the breathing zone height peaking at 28,786 mg/m3. Furthermore, activating the inter-support spray-induced dust removal device boosts the airflow velocity to 15.8 m/s, generating negative pressure at the dust suction inlet and forming a high-concentration droplet zone near the coal wall. During the operation of the combined system, the droplet distribution is characterized by “three high-concentration areas” and “post-nozzle attenuation.” The optimal droplet proportion reaches 93.81%, maintaining an appropriate velocity within the efficient dust capture range. Overall, the dust capture efficiency of the combined system is significantly superior to that of a single spray system.