Design and Evaluation of a Novel Solid Spray Dust–Suppressant for Coal Mine Dust Reduction Based on a Molecular Dynamics Simulation

Coal mine dust significantly impacts miners’ health. Water spraying is widely employed but has limitations including inadequate coal dust wetting, transportation difficulties, and operational complexities with liquid dust suppressants. To address these, this study developed a novel solid spray dust suppressant (S-SDS). Through molecular dynamics simulation, experiments, and field evaluations, the dust suppression performance of the S-SDS was assessed to verify its effectiveness in reducing the coal dust concentration in coal mines. The results identified the optimal composite sodium dodecyl benzene sulfonate (SDBS) and isomeric alcohol ethoxylates (1307) for target gas fertilizer coal, with a coal–water interface thickness of 17.22 Å (309% increase relative to the water system) and an interaction energy of −187.77 kcal/mol. Sucrose was selected as the curing agent for the S-SDS. When the mass ratio of SDBS:1,307:sucrose was maintained at 4∶1∶2, the hardness of the S-SDS was moderate and the dissolution rate of the S-SDS was optimal. Compared to water spraying, application of the S-SDS solution (30 g/L) reduced the coal contact angle to 14.7° (an 87.12% reduction) and increased the capillary rise height by 329.09%. The S-SDS release unit is installed in series upstream of the spray system, requiring no electrical power or additional energy supply. This configuration eliminates the need for high-pressure pumps, thus enhancing operational safety. Furthermore, S-SDS demonstrates advantages in transport, storage, and addition, with its controllable release rate enabling continuous operation for at least one week per addition. Field tests demonstrated that this system achieved an average dust suppression rate 29.28 percentage points higher than water spraying. This approach provides a practical solution for coal mine dust control.