Inhibition of fine particles fugitive emission from the open-pit lignite mines by polymer aqueous solutions

摘要

To reduce the fugitive emission of fine particles from the open-pit lignite mines, a dust suppressant was proposed by applying a blend of 0.7% water-soluble polymer (guar gum) and 0.1% nonionic surfactant (Triton X-100) in this paper. The characteristics of the polymer protection film formed on the lignite sample's surface, as well as the wetting performances of surfactants on lignite were investigated, and the simulated dust suppression experiments aimed for the inhibition of lignite fine particles were also carried out. The results showed that the polymer molecules could adhere to the lignite fine particles through the solid-bridge force to form a polymer protective film, and the solid-bridge force between the lignite particles and polymer molecules was a type of chemical force. GG solution showed excellent solidified and anti rain erosion properties. The surface tension and contact angle of GG solution were obviously reduced with adding surfactant, and Triton X-100 with a mass concentration of 0.1% was chosen as the wetting component of the lignite dust suppressant. Besides, the lignite dust suppressant showed superior removal performances on lignite fine particles, and could effectively reduced the fugitive emission of fine particles in windy weather. When the air flow speed was in the range of 5-15 m/s, the dust suppression efficiency on lignite fine particles was above 98%.