Differential grinding

摘要

There is described a process for the isolation of a fine mineral product from a low-grade source of the said mineral, the process comprising the following steps: (i) forming a suspension in water of the said mineral source; (ii) subjecting the suspension to grinding with a grinding medium having a specific gravity not greater than 2.0, the amount of energy dissipated in the suspension during the grinding operation being not greater than 50 kW.hrs per tonne of the dry mineral source; and (iii) isolating from the ground suspension a fine fraction of particles comprising an increased amount of the said mineral when compared with the same fraction isolated from the unground mineral source.