A specific energy-based size reduction model for batch grinding ball mills was reported in a previous
paper (Shi and Xie, 2015). A discharge function modified from the Whiten classification efficiency equation
has been incorporated in the size reduction model to extend its applications from batch grinding to
continuous operation. Five sets of the industrial ball milling survey data were used to validate the ball
mill model. The data were acquired from four full scale ball mills covering primary and secondary grinding
duties in a gold concentrator and a PGM concentrator. In all cases, the model fits the ball mill operational
data well.
Features of the specific energy-based ball mill model include the use of an ore-specific and sizedependent
breakage function, whose parameters are independently measured with a fine particle breakage
characterisation device, the JKFBC. This allows simulations of the effect on ground product size distribution
of changing ore breakage characteristics. The model utilises separate selection function and
discharge function, which permits the investigation of the influences of mill operational conditions on
grinding performance.