In order to effectively prevent the diffusion and pollution of highly concentrated PM2.5, the roadway full-section water curtain device has been developed in this paper. Based on our water spray experiments, a type II nozzle that was suitable for the water curtain device was selected. This roadway full-section water curtain device was optimized through a numerical simulation using Fluent software. The wind -droplet numerical simulation results showed that the water curtain device could achieve the optimal spray parameters. When the water pressure Pw was 7 MPa and the nozzle was inclined to the upwind side at theta = 15 degrees, a high-quality spray field with the concentration greater than 10 g m(-3) covered 93.1 % of the cross-sectional area of the entire roadway. The settlement of harmful particulates of PM2.5 in the air-return pathway of the Bailu Coal Mine's 4307 coal mining face, using three roadway full-section water curtain devices, was then measured. The results showed that the ideal level of dust settlement can be achieved by consuming less water. It was also found that the settling rate of PM2.5 at the air-return pathway 200 m away from the coal mining face was as high as 95.7 %, indicating that the roadway full-section water curtain device had settled and controlled the PM2.5 in the roadway's airflow effectively. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.