Investigating the impact of impeller geometry for a stirred mill using the discrete element method: Effect of pin number and thickness

Abstract

Vertical stirred milling is a major technique for grinding fine and ultra-fine particles. In this study, attritor designs of varying pin number and projected area were examined over a range of impeller rotational speeds using the Discrete Element Method (DEM). Analysis determined that additional pins improved the potential for effective grinding due to an increase of average collision energy. However, this was accompanied by a greater power draw. When projected area was maintained, there were fewer differences between designs, meaning that the specific configuration of the pins may not be as important. A template of the mill can be found at https://github.com/darhyme147/ligggghts_stirred_mill_template.