Effectiveness of Protein and Polysaccharide Biopolymers as Dust Suppressants on Mine Soils: Results from Wind Tunnel and Penetrometer Testing

For the dust control of barren mine soils, protein and polysaccharide biopolymers have recently shown potential as environmentally friendly alternatives to conventional dust suppressants (e.g., salt brines or petroleum-based products). However, laboratory studies that determine suitable application parameters are required for large-scale field trials. This study performed wind tunnel and pocket penetrometer tests to investigate the wind erosion and penetration resistance of treatments with different biopolymer types, concentrations (wt%), and application rates (L/m2) on two mine soils. The results demonstrate that all treatments significantly enhanced the wind erosion resistance of both tested soil types, with the biopolymer type, concentration, and application rate having a significant effect. Depending on the biopolymer type and application parameter, the wind-induced soil loss ranged from 0.86 to 423.9 g/m2 (Control = 2645.0 g/m2) for medium-grained sand and from 0.3 to 225 g/m2 (Control = 26,177.0 g/m2) for fine-grained silica sand, with the soil loss reducing as concentrations increase, until it reached a plateau concentration. For a similar performance, the tested proteins (wheat and fava bean protein) must be applied at higher concentrations than those of the polysaccharides (xanthan gum, corn starch, and carboxymethylcellulose). Spearman rank correlation revealed a moderate-to-strong negative correlation between soil loss (g/m2) and penetration resistance (N), rendering the pocket penetrometer a rapid, low-cost, and indirect method for evaluating potential dust suppressants. This research contributes to evaluating biopolymers as alternatives to traditional dust suppressants for controlling dust emissions on barren surfaces. Biopolymers are biodegradable and can be sourced regionally at a relatively low cost, reducing the environmental impact and expenses associated with dust suppression.