POWER-CONSUMPTION IN CENTRIFUGAL AND NUTATING MILLS

Centrifugal and nutating mills offer a high-intensity grinding environment in a relatively small machine, with power intensities as high as 2500 kW/m3. A necessary step in modelling the behaviour of these mills is to calculate the theoretical power required to tumble the mill charge, and to develop scale-up methods so that the power consumption of any centrifugal or nutating mill may be estimated from experimental power measurements on a test mill. The power consumption is shown to be a function of mill dimensions, mill speed, the amount of material in the mill, and the bulk density of the mill load. A method for calculating the theoretical power consumption from these operating conditions is presented, and it is shown to compare favourably with experimental measurements in both centrifugal and nutating mills.