USE OF GRINDING AND LIBERATION MODELS TO SIMULATE TOWER MILL CIRCUIT PERFORMANCE IN A LEAD ZINC CONCENTRATOR TO INCREASE FLOTATION RECOVERY/

The paper presents findings from collaborative research on fine grindi ng, coordinated by the Australian Mineral Industries Research Associat ion. The data reported here were collected from a tower mill circuit i n the low grade mineral section of Mt. Isa Mines' Hilton Concentrator, Multi-component modelling, based on assays of size fractions, showed that the circuit was capable reducing the fresh feed from 110 to 15 mu m at the desired throughput using about 22 kWh/t, provided classifica tion at around 27 mu m was installed. A benefit of about 3% recovery o f both lead and zinc was indicated, A new simplified method of modelli ng grinding and liberation together is explained and verified by using parameters from the normal grind to predict, quite accurately, the si ze reduction and liberation achieved in a finer grind.