Technologies for effective coal dust suppression using surfactants: A review of dust suppression programs and evaluation criteria

Coal dust ranks among the five major mine disasters, endangering the mine environment and workers’ health. Traditional dust suppression methods often fall short of expectations. While numerous studies have shown that surfactants can effectively inhibit coal dust, a systematic explanation of their mechanism remains lacking. This paper comprehensively reviews the use of surfactants for efficient coal dust suppression. It details the pros and cons of traditional processes like coal seam water injection, spray dust removal, and foam dust removal. Considering the structures, ion effects of different surfactants, and their complex impacts on the coal dust inhibition rate, the paper determines the adsorption forms of various surfactants on coal dust surfaces. Results show that the inhibition effect on coal dust follows the order: anionic > nonionic > amphoteric > cationic. Also, the alkyl chain structure, benzene ring structure, ethoxy group structure, benzene ring position, and bond types significantly influence the inhibition rate. Moreover, the combination of anionic and cationic surfactants may bring unexpected benefits, and anionic-nonionic surfactants can synergistically wet coal dust, while other mixtures are less likely to show stronger advantages. The paper further analyzes evaluation methods at different levels, proposes optimal application conditions, explains each method’s evaluation mechanism, and constructs an evaluation system model for coal dust wettability from multiple perspectives of “macro experiments + meso characterization + micro simulation + theoretical calculation”. Finally, it optimizes the design of efficient coal dust suppression schemes and outlines future development directions and prospects.