Abstract:
In order to solve the coal dust pollution problem in the process of coal mine production, transportation and storage and reduce the incidence of pneumoconiosis among coal workers, based on the concept of natural polymer modification, a gel film-forming component was synthesized through graft copolymerization of N-hydroxymethyl acrylamide (NAM) chains onto a composite substrate of xanthan gum (XG) and hydroxypropyl methylcellulose (HPMC) under the action of initiators and cross-linking agents, this modified component was subsequently compounded with the surfactant sodium dodecyl sulfonate (SDDS) and the humectant polyvinylpyrrolidone (PVP) to fabricate a crust-type coal dust suppressant featuring a gel network structure. The grafting process and dust suppression mechanism were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) elemental analysis, and scanning electron microscopy (SEM). The performance advantages were validated through viscosity tests, swelling capacity tests, and dust suppression performance tests. The results demonstrated that the gel network structure within the dust suppressant significantly enhanced the cohesive properties and swelling capacity of the material. This improvement effectively bonded coal particles and formed a dense consolidated layer on the coal dust surface, thereby enhancing the dust suppression efficiency; in the water retention test, the dust suppressant-treated coal sample exhibited a water retention rate exceeding 50% after evaporation at 45 ℃ for 5 h; in the consolidation layer weather resistance test, the dust suppressant-treated coal samples exhibited a 79.5% enhancement in wind erosion resistance efficiency compared to traditionally water-sprayed samples under a wind speed of 15 m/s, while the consolidated layer morphology remained intact. In the wind erosion resistance test, the dust suppressant-treated coal samples subjected to 7 freeze-thaw cycles between −20 ℃ and 50 ℃ exhibited only a 12% reduction in consolidated layer hardness, with no visible cracks observed in the consolidated layer. The study shows that the developed gel-based dust suppressant significantly suppressed coal dust dispersion, thereby offering a novel approach for environmental protection in mining areas and occupational health safeguarding for coal miners.