Title : The urban mining challenge in recovering value from secondary material in anthropogenic stocks
The scarcity of mineral resources and the prices fluctuation of demanded materials represent some of the aspects that most concern producers around the world. The pandemic and wars condition brought the need to guarantee the supply of raw materials. Internationally, the establishing criteria for defining critical materials consider the supply risk and economic value of materials from natural sources. The use of secondary materials from residual sources has been prioritized in different countries and motivated the elaboration of legal and normative instruments and encouraging the development and consolidation of recovery techniques. The technologies and processes available today for environmentally sound management of waste and tailings seek to include the principles of the circular economy which, in turn, comprise the recovery of value from the extension of the useful life of products. The recovery of secondary materials can be considered as a process of mineral transformation from residual sources using basic metallurgy techniques. Unlike conventional mining, urban mining has a greater potential for mineral concentration since the products have a known mass balance and more efficient recovery channels by eliminating some of the processes. It is estimated that the growth of world e-waste generation is between 3 and 5%, representing an increasing source of secondary material from anthropogenic stocks, demanding efficient reverse logistics and traceability potential.