Inhibition characteristics of polymer suppressant on fine particles in lignite mines

To reduce the fine particles in lignite mine and avoid serious harm to human health,production safety and the atmosphere,four poly monomers were selected. Through the attenuation of crust hardness and anti-rain erosion ex- periment,guar gum was ascertained to be a monomer with excellent properties. Through the surface tension and contact angle experiments,Tween-20,Triton X-100,sodium dodecyl sulfate and sodium dodecylbenzene sulfonate were com- pared to determine which one has the best wetting property for lignite particles. Nonionic surfactant Triton X-100 was found to be the best. A crust type of lignite dust suppressant was developed by modifying guar gum with nonionic sur- factant Triton X-100. The effects of monomer concentration and wind speed on the number concentration and size dis- tribution of cured layer after wind erosion were investigated. The optimal dust suppressant formulation was guar gum at a mass concentration of 0. 7% and Triton X-100 at 0. 1% . It indicates that a protective layer with a certain thickness and strength is formed on the coal surface after the spraying of suppressant,and the hardness can reach 61. 43 after 10 days. The solidified layer can resist the erosion of 15 m / s wind speed,and is enough to cope with the windy weather in the north. Furthermore,the number concentration decreases to 3. 69×105 cm-3 ,the peak of particulate number concen- tration appears at about 0. 85 μm. The removal efficiency of particulate matter in low size segment increases from 30． 1% to 94. 4% ,and the inhibition efficiency of fine particles with a diameter of about 0. 1 μm increases by 64% . The results show that the suppressant has an obvious effect on restraining fine particle. And it is an easily available, environmental-friendly and high-efficiency dust suppressant for lignite mines.