Operation. In operation, air enters through the air inlet in the grinding chamber’s bottom and flows upward from
under the rotor disc, entraining the entering feed material and directing it into the grinding zone. The rotating ham-
mers impact the particles and deflect them into the liner, where the liner’s vertical grooves slow the particles’cir-
cumferential speed and deflect them back into the ham-
mers’ path to maximize the impact force on the particles.The reduced particles are carried upward by the airflow,
and the baffles in the shroud-and-baffle assembly help direct the particles into the classification zone. Fine particles
pass through the slots between the classifier wheel’s vanes and flow with the air out of the product-and-air outlet, while
coarse particles that can’t pass through the classifier wheel are returned to the grinding zone for further reduction.
Other common air classifier mill variations include mills with a horizontal classifier wheel, a combined classifier
wheel and rotor drive, a vertical rotor, or an easy-to-clean design. Their operation is similar to that of the vertical air
classifier mill, but they’re configured differently.