Theory and application of dust prevention and control in fully mechanized mining face with large mining height

To address the problem of dust pollution in fully mechanized mining faces caused by large mining height technology, and considering the significant characteristics of such faces — including large stope space, long dust diffusion distance, multiple dust sources, and high dust generation intensity — this study proposes a source-based and zone-based dust control method for fully mechanized mining faces with large mining height, based on the temporal and spatial evolution law of respirable dust. The proposed method consists of four key technologies: three-dimensional enveloping high-efficiency spray dust suppression for the shearer drum technology, dust-laden airflow control around the shearer, closed dust guiding with hydraulic supports, and dust isolation and removal using negative pressure micro-fog technology. Through theoretical analysis, numerical simulation, and laboratory experiments, the key process parameters of the above technologies and their influencing laws were obtained, and a dust prevention and control theory as well as a complete set of technologies suitable for large mining height fully mechanized faces in China were finally established. Field tests and applications results show that this technology reduces the concentration of respirable dust in personnel working areas by more than 90%, significantly improving the hygienic conditions of the working environment.