The grinding mill is one of the necessary equipment in pelletizing shaft furnace. It deals with water content in the 7~9% material, its working principle is material (iron concentrate powder and bentonite) after the end of the feeding belt feeding device into the barrel internal rotation, the material by grinding media - ball impact, as well as between the ball and the ball, the ball and the cylinder liner between the grinding fresh, fully exposed surface, and are fully mixed, the -200 content (feed size) increased by more than 10%, the discharge hole cylinder discharged outside the machine, enter the next procedure balling. The characteristics of the mill are: forced feeding, rubber lining and peripheral discharging.