Increased potential of recyclable materials
Optimization of the processing of NF metal concentrates from waste incineration ashes
Summary: The processing of waste incineration slag (WI bottom ash) has been steadily developed in recent years, with the aim of maximizing recovery of the resources contained in the bottom ashes. Focus is on the recovery of metals present after the combustion process either in free form or as inclusions. In cooperation with the engineering company pbo (Aachen) and RHEWUM GmbH, a new approach was taken in the processing of metal concentrates, which is described in the following.
1 Introduction
In standard processes for processing WI bottom ashes, following coarse primary classification, usually at cut-points between 40-100 mm, magnetic separators are used to remove any magnetizable iron components. Non-ferrous metals are usually recovered with eddy current separators. The disadvantage of this system is that metals recovered in this way exhibit considerable contamination with mineral slag residue. These contaminants consist of fine particles and particle agglomerates that stick to the metallic components, forming composites. The adhesive forces within these composites...