Comparative investigation of methods for evaluating the wettability of dust suppression reagents on coal dust

Dust suppression materials are most commonly used in dust control practices, and evaluating their wettability is crucial in predicting control effectiveness. This study developed an impact wetting experiment that used the wetting area to characterize the wetting behavior of droplets on coal dust. The surface tension test, contact angle test, sink test, penetration test, capillary rise test, and impact wetting experiment were performed for comparative study. The wetting effect of the dust suppression reagent solutions on coal dust was analyzed, and the advantages, disadvantages, and applicability of each method were indicated. The experimental results revealed that the impact wetting experiment was applicable to evaluating wettability and demonstrated a high discriminatory ability, showing superior evaluation efficacy. The wettability order of the selected reagents was SDBS > SDS > OP-10 > OP-7 > OP-4, which was also supported by molecular dynamics simulations. The findings of this study serve as a useful reference for the selection and evaluation of coal dust suppression reagents.