Mineral Processing Techniques Dedicated to the Recycling of River Sediments to Produce Raw Materials for Construction Sector

Dredged river sediments produce a huge volume of mineral materials, which could be incorporated into building materials. Considering the raw sediment preparation, mineral processing techniques fit perfectly to this purpose. This work describes two procedures to prepare river sediments, according to the final beneficial use. The first is a dry procedure of deagglomeration to prepare river sediments with the aim of being incorporated into a concrete formulation to build a bicycle path. A large amount of deagglomerated sediment was prepared, requiring upscaling of the deagglomeration process. Successive steps of sieving and roll crushing were used to obtain deagglomerated sediments. To use it as raw material to produce pozzolanic materials and lightweight aggregates, a second procedure consisting of a wet classification at 63 µm was carried out. Steps of wet sieving, followed by hydrocycloning and screw classifying, were used to prepare several silt fractions under 63 µm.