Waste mining in the Circular Economy - Impact of flow, heat and mass transfer conditions on the partitioning kinetics of critical metallic elements in thermal treatment processes for contaminated non-recyclable waste

In the production of bulk and consumer goods, specific chemical compounds are added in small amounts to establish desired material properties, such as strength, conductivity, colour fastness and resistance to e.g. UV, corrosion, chemical impact, heat, fire and fungal rot. Whereas these added compounds contribute to a higher quality and an extended lifetime of goods on the one hand, on the other hand they make recycling of constituting material(s) difficult or even impossible when these goods are no longer used and turned into waste. However, as material additives often contain metallic elements recognized as critical for the Circular Economy, this creates opportunities for advanced recovery of such elements through thermal treatment of non-recyclable waste streams. In view of maximizing the recovery potential, in this PhD research project is investigated experimentally how process conditions applied in high-T waste treatment plants ultimately affect the partitioning (i.e. the solid/gas distribution) of defined elements present in the waste. Furthermore, data and quantitative relations obtained enable to generate insights in how to reduce/avoid specific types of high-T corrosion typically occurring in existing Waste-to-Energy plants.