A comparision of wet and dry autogenous grinding

There has been a well established “truth” that wet grinding is more efficient than dry grind-ing. This should apply to ball mill grinding as well as autogenous grinding. It has been earlier shown that the effect of dry ball mill grinding increases considerably, when the fines are efficiently removed from the mill. In this work autogenous grinding in small continuos scale has been undertaken to compare the effect of fine particle removal from the mill charge by efficient classification both wet and dry. It could bee seen from the charge composition and from analysis of 43, 74 and 145 µm product particles that internal friction remained best in wet grinding, although the difference to the dry grinding where fines were most efficiently removed was relatively small. The differences still remaining are probably due to less efficient removal of particles in the 1 mm range which can not be transported by air.