Sulphide Flotation. In practice, sulfide flotation plants operate at pulp potentials that are in the range of +50 to +200mV versus SHE (Grano, 2004) and the value depends on the pulp pH, type and quantity of sulfide minerals, the type and quantity of grinding media (Rao et al., 1976), and the amount of air–pulp contact in and after the grinding circuit (Teague et al., 1999b).