Abstract
To define the comminution mechanism and achieve a high recovery of fine particles, dry tower mill KD-1 and KD-2 have been developed and modified into KD-3. In this study, grinding tests were carried out on limestone to clarify the comminution mechanism in the KD-3.
A particular attention was paid to important factors such as size of the grinding media (steel balls of ∅10mm, ∅13mm, ∅16mm, ∅20mm), the speed of the stirring screw [from 1.08s-1 (65 rpm) to 1.58s-1 (95 rpm)] and the role of nets in the classifying column. The study has revealed an optimum efficiency for steel balls of ∅20mm size and stirring screw rotating at 1.58s-1 (95 rpm). Besides, the maximum particle diameters of products were indicated by the corrected curve which is estimated by the assumption of Stoke's law. The relationship between maximum and 50% particle diameters was proportionally and by using the columns provided with nets, the overflow products were classified by high classifying efficiency.
