FROTH FLOTATION FOR BENEFICIATION OF PRINTED CIRCUIT BOARDS COMMINUTION FINES: AN OVERVIEW

摘要

End-of-life printed circuit boards (PCBs) are a complex secondary resource stock that continues to evolve more complexly in new generation devices. This is a major challenge in its physical processing. The value of precious and base metals loss to the -75 mu m fraction generated during PCB comminution has been identified as a major constraint toward improving physical processing. Application of froth flotation for beneficiation of this fines fraction is conceivable, as each group of particles in the mix has distinct surface properties that can be exploited. However, recognizing the complex flotation system such a sample can produce, an informed discourse has been presented herein: starting from a characterization of the resource stock, then to a review of almost three decades of PCB physical processing, before attempting to simplify the flotation complexities. This overview is intended to be a springboard for detailed investigations into this theme.