The perfect mixing model (PMM) is based on parameters derived from the equipment characteristics as well as ore breakage characteristics. Ore characteristics are represented through the appearance function. This function may be determined using JKMRC laboratorial methods or by standard functions. This work describes the model fitting process of the Carajas grinding circuit, using the JKSimMet simulator. Two scenarios were used in model fitting exercises: 1) standard appearance function; and 2) appearance function based on testing carried out on samples taken at circuit feed. From this assessment, the appearance function's influence in the PMM fit and it's relation with the breakage rate were determined. The influence of the appearance function on the respective breakage rate distribution was assessed.
Grinding; perfect mixing model; iron ore
