The effects of moisture content (10% to 20%) on the
grinding behavior of corn and corncobs at three moisture
content levels were studied. Heat generated by friction
during the grinding process resulted in significant moisture
loss from ground materials at higher initial moisture
contents. This moisture loss must be accounted for when
computing the mass balance of the grinding system and the
desired yield of ground material. Throughput and specific
rate of breakage of the corncobs decreased with an increase
in moisture content, with no significant change for corn
within the investigated moisture content range. The average
power consumption and energy required for grinding
corncobs was higher than for grinding corn. The energy
required for grinding these feedstock materials at different
moisture contents was significantly different, and scaling
up to an industrial production process could result in higher
energy consumption at higher moisture levels. Particle size
distribution depended on the initial moisture content of the
feedstock material; higher yields of larger-sized particles
and a broader PSD were observed as the moisture content
increased for both corn and corncobs. The geometric mean
diameter of the ground corn was lower than that of ground
cobs at all moisture levels. This caused the ground cob
samples to have lower bulk density, compressibility index,
Hausner ratio, and angle of repose than the ground corn.