ABSTRACT
This chapter describes pre-treatments for the enrichment of precious metals from spent electronic waste and catalytic converters. The development of dismantling, comminution, shredding, crushing, screening, classification, and concentration is extensively covered. Single, dual and quad-shaft shredders, primary, secondary, tertiary, and impact crushers, and ball, rod, pebble, autogenous, and semi-autogenous mills for grinding are explained in detail. The use of grizzly, trommel, vibratory, and gyratory screen separators and hydraulic, spiral, and hydrocyclone classifiers as a pre-concentration step is also explained. Concentration of precious metals from urban mine sources by sorting, gravity-/density-based methods, spiral concentrator, jigs, magnetic separation, electrostatic separation including corona, triboelectric and eddy current methods, froth flotation, and support material dissolution are also introduced.
