M. Aazami, A. Khodadadi, A. Farzanegan,
Volume 4, Issue 3 (12-2007)
Abstract
Abstract: The specific rate of breakage is one of the most important factors in evaluation of
grinding process especially in ball mill. In this article the effect of ball size and feed size on
selection function were investigated using batch grinding circuit on two-iron ore anomaly (B, C)
from sangan mine in north of Iran. Eight different monosize fractions were prepared between 2000
and 500 microns, using a 2 sieve series. The specific rates of breakage (Si) were determined from
the size distributions at different grinding times, and the specific rates of breakage were compared
for three different ball diameters (25.4, 16.6 and 9.6 mm). The results showed that the breakage
function of both anomalies is normalizable (independent to the particle size) and it is independent
to the ball size. But the specific rate of breakage variate with feed size and ball size. Also optimum
size of balls for grinding of this feed obtained to be between 9.6-16.6mm.
