Preparation and Characterization of an Environmentally Friendly Dust Suppressant for Crust in a Nondisturbance Area of an Open Limestone Mine

ABSTRACT To solve problems caused by dust pollution in open limestone mines, environmental dust suppressants were prepared with natural polymer extracts as raw materials. The proportion range of guar gum (GG), sodium carboxymethyl cellulose (CMC), and sodium dodecyl sulfate (SDS) as the single components of the composite dust suppressant (CDS) was determined by a single‐factor test. Response surface methodology (RSM) was used to optimize the mix design, and the weather resistance, compressive strength, and cost of CDS were tested and compared with many commercial dust suppressants. Microscopic tests were used to analyze the structural properties and functional group changes in CDS. The results showed that the optimal concentration of the CDS agent was 0.192% GG, 0.3% CMC, and 0.351% SDS. Under the optimal ratio, the viscosity of CDS was 119.56 mPa∙s, the pH was 7.62, the surface tension was 30.3 mN/m, and the price was 83.3 RMB/t. The dust hardness after 7 days of spraying CDS was 87 HA. CDS exhibits good resistance to rain erosion, pressure resistance, freeze–thaw resistance, and wind erosion. CDS formed a cross‐linked structure by linking the amide and carboxyl groups, which can significantly reduce porosity, and form a compact and flat solidified layer, which has good dust suppression performance.