The impact of different stirrer designs and mill orientations on the grinding efficiency

Abstract

The primary objective of this research is to examine the impact of various stirrer designs in different mill orientations on the efficiency of calcite grinding in a dry stirred mill. In the context of the research, a series of batch grinding experiments were performed using a laboratory-scale stirred mill that could be oriented vertically or horizontally. Four distinct stirrer designs, namely 3-pin, 5-pin, 3-disc, and 5-disc, all with the same diameters, were employed in these studies. Stress intensity analysis was used to evaluate the experimental outcomes. The findings indicated that the number of stirrers present on the shaft, whether in the form of pins or discs, significantly influenced the effectiveness of the grinding process. Furthermore, the horizontal orientation performance of the 5-disc design provided the best particle fineness compared to other combinations. Additionally, the batch grinding experiments provided indications that the disc design yielded favorable results when employed in the horizontal mill configuration, while the pin design proved to be successful when utilized in the vertical mill configuration. Aside from these, design variations had an impact on the particle size distribution width characteristics of the products. The design parameters were also evaluated in terms of the stress intensity-particle size distribution width relationship.