Characterization of Fluidized Bed Sands from the Forest Value Chain for Use on Unpaved Roads

Unpaved forest roads are commonly used to provide access to forest areas for the operations associated with the exploitation of their products, to prevent and fight forest fires and for leisure activities. The forest value chain incorporates a multitude of diverse industries that generate a range of byproducts as part of their activities. One of these byproducts are fluidized bed sands, produced in the biomass boilers used for energy generation at pulp and paper plants. Heretofore, these byproducts were rejected like a waste and stored in waste landfills. Currently, efforts are ongoing to reuse the fluidized bed sands in unpaved forest roads. This approach promotes circular economy and the use of these byproducts as a valuable resource. Initial findings relating to the potential use of fluidized bed sands for unpaved roads are presented. In particular, geotechnical and chemical properties of these sands are evaluated and compared with the requirements for application as aggregate or infill soil on unpaved roads. The chemical and geotechnical properties of the byproducts tested fulfil the requirements of several guidelines. Therefore, these byproducts have potential to be used to replace natural materials in unpaved forest roads without negative environmental impacts.