Research on Optimized Design, Synthesis Mechanism, and Performance of Composite Dust Suppressant for Laterite in a...

Currently, a paucity of targeted dust suppressants exists for the management of laterite dust, and most of them lack sufficient resistance to the harsh conditions in the plateau areas, such as high temperatures, low rainfall, and wind erosion. To solve the problem, a new type of dust suppressant must be developed. Initially, xanthan gum was employed to enhance the viscosity and stability of guar gum. Subsequently, the synergistic mechanism between the reagents was considered, and the composition of the composite dust suppressant was selected as poly(acrylic acid), sodium dodecyl sulfate, guar gum, and xanthan gum by one- and two-factor methods. The dosage of each component was then determined via orthogonal experiments. To increase the suitability of the dust suppressant in high-temperature and low-humidity environments, hydroxypropyl methylcellulose was added to enhance the "film" effect. Both intuitive and polar analysis methods demonstrated that the composite dust suppressant was the optimal choice for controlling laterite dust emissions. The performance test experimental results show that the dust suppressant can fill the gap between particles well after spraying, the solidified layer formed is flat and smooth, and the moisture content of the sample was still above 9% after 72 h. The hardness of the consolidation layer can reach 42 HA, which can resist the destructive ability of external force; when the wind speed is 7 m/s, the mass loss rate stays below 0.63%, and the emission concentrations of PM_2.5 and PM₁₀ are 32 μg/m³ and 43 μg/m³, respectively, which is in line with the requirements of the emission standards. The dust suppressant components are all less toxic to plants, and the degradation rate can reach 57.84% in the sixth cycle, ensuring degradability and biocompatibility. The composite dust suppressant demonstrated superior performance to that of the two commercially available dust suppressants. It exhibited remarkable adaptability to harsh environments, effectively regulating construction site dust emissions and reducing particulate matter in the air.