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 PM
10
are 32 μg/m
3
and 43 μg/m
3
, 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.