Construction of high-precision macromolecular model of Zhaozhuang anthracite based on microscopic level and optimization of surfactant applicability: Efficient control of coal dust

Abstract

The coal mining process is plagued with problems such as low dust removal efficiency and blind selection of dust reduction means due to the lack of microscopic molecular modelling of coal dust. Taking coal samples from the Zhaozhuang Coal Mine in Henan Province, China as an example, a series of chemical analyses were performed to determine the types and amounts of constituent structure in coal dust molecules. The molecular formula of coal dust was be C₁₈₁H₁₄₂N₂O₂₁, from which planar and three-dimensional macromolecular structural models. To find the most suitable surfactants for the model, sodium dodecyl benzene sulfonate (SDBS), sodium fatty acid methyl ester sulfonate (MES), and coconut oil fatty acid diethanolamide (CDEA) were selected, and the effects on their wettability were analyzed with simulations and experiments. The adsorption state of water molecules in the different water-surfactant-coal ternary systems was simulated and analyzed in terms of the radial distribution function and the mean square displacement. It was found that the value of radial distribution function of SDBS system was 5.19, and the diffusion coefficient was 0.66 Ų/ps, which were the highest for the different systems. The experimental results showed that the surface tension of a 0.36 wt% SDBS solution was 27.130 mN/m, and the contact angle was 25.2°, both of which were the lowest for the different surfactant solutions and had the best wetting effect. The coal dust model construction combined with the analysis method of surfactant selection provides a new method for coal dust directed dust removal.