Food processing by-products and wastes as potential dust suppressants at mine sites: Results from unconfined...

The application of dust suppressants is an effective technique to reduce fugitive emissions, but commercially available products are costly and may harm the environment. By contrast, wastes and by-products from food production and processing can be sustainable alternatives, as they are biodegradable, considered cost-effective and have adhesive properties. The study aimed to investigate the application potential of biogenic wastes and by-products from the food industry to control dust emissions from mine soils. Unconfined compressive strength tests (UCS) were conducted on medium- to coarse-grained sand treated with sixteen biomaterials at two different additive concentrations (2 wt%, 4 wt%). UCS tests showed that rinsing water from jam production (1,366 kPa), corn steep liquor (1,502 kPa), chicory vinasses (1,723 kPa), decantation syrup (2,026 kPa) and palatinose molasses (7,535 kPa) significantly enhanced the mechanical strength of the substrate (11 kPa), indicating a strong potential of these biomaterials as dust suppressants. Such biomaterials that contained biopolymers and not only mono- and disaccharides achieved on average higher UCS values, possibly due to the formation of 3D-network structures. Moreover, the data indicated a low potential for substances with high glucose and fructose content, as they had minor or no impact on soil strength.Implications: The UCS test results indicate that food processing wastes and by-products can be sustainable alternatives to existing dust suppressants. Hence, the present study supports an environmentally friendly and cost-effective dust control of exposed surfaces at mine and mineral processing sites and provides new markets for the food industry's wastes and by-products. Moreover, this research extends our understanding of dust suppressant treatment of soils and contributes to evaluating biogenic food processing wastes and by-products as environmentally benign dust suppressants.