A laboratory ball mill consisting of vertical cylinder, equipped with a
rotating shaft with arms, and filled with steel balls as a grinding medium
has been used in the experiments. The aim of the study was to examine the
effect of agitator shaft speed and amount of grinding media (steel balls) on
power requirements and energy consumption of a ball mill. With constant mass
of the steel balls (20 kg, 30 kg and 40 kg), the agitator shaft speed was
increased from 10% to 100% of the maximum speed which corresponds to a speed
of 50 rpm. The power consumption (W) was recorded upon which milling energy
consumption (J/kg) has been calculated. The results were statistically
analyzed using ANOVA. The increase of the agitator shaft speed, in steps of
10% to the maximum speed of 50 rpm, led to a statistically significant
increase in milling energy consumption. At low agitator shaft speed (10%),
increase in the mass of the steel balls had no influence on the power
requirements. Power requirements for the grinding runs using 30 kg and 40 kg
are similar and higher compared to power requirement in trial with 20 kg, as
agitator shaft speed increases from 20% to 70%. At high agitator shaft speeds
(?80%), increase in steel balls mass led to the significant increase in power
requirements of the ball mill.
The effect of processing parameters on energy consumption of ball mill refiner for chocolate
