Geometry influence on optimized operation of a dry agitator bead mill

In the search for energy reduction potential, a large number of systems in the energy-intensive industrial sector of comminution are being investigated. In addition to the requirement for constant minimization of energy consumption, the demand for higher quality and fineness of the manufactured products is growing. These two requirements can usually only be met by new developments of milling equipment. Such a new development and the subsequent optimization of the process-determining parameters are presented here. The mill under investigation is a dry-operated agitated bead mill, whose design and mode of operation is based on a wet-operated bead mill. Five essential parameters for the plant operation of the dry agitator bead mill have been investigated: Besides filling level of the grinding media and circumferential speed of the agitator to achieve a reliable reference operation setup, particularly the number of agitators and the resulting distances between them, respectively, the wall distance of the agitator arms and the recirculation load in classifier-closed-loop operation. By adjusting the operating and geometry parameters, the specific energy consumption can be decreased from more than 150 kWh/t to about 80 kWh/t. Based on the findings of this work, the influence of individual parameters is shown and evaluated for the application under consideration. Thus, an optimal setup for the machine operation is defined.