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• Measurement of the grinding bodies' motions in a vibratory disc mill. • Influence of the viscosity on the grinding bodies' motions. • Influence of the filling quantity on the grinding bodies' motions. • Horizontal and vertical grinding bodies' motions. The grinding bodies' motions (grinding disc and grinding ring) in the mill chamber of a vibratory disc mill have been experimentally studied and subsequently evaluated as well as interpreted in detail. The horizontal movements have been recorded by means of a high-speed camera positioned perpendicularly above the mill and the vertical movements using a measurement sensor, which enables a sensitive measurement of the grinding disc's variation in height. Simultaneously, the influence of the fluid viscosity and the fluid's filling quantity on these movements have been determined. Both parameters distinctly influence the grinding bodies' motions. An increasing viscosity shows initially no visible influence on the grinding bodies' centre velocities. In the case high viscosities are reached, a significant decrease in the grinding bodies' velocities appears due to the higher flow resistance or more specifically, higher fluid's resistance or lower fluid's flowability counteracting the motions. Due to increased sliding of the grinding bodies on a highly viscous fluid, an inversion of the grinding bodies' direction of rotation develops additionally. A larger fluid's filling quantity causes a reduction of the sliding friction between the elements, wherefore the grinding bodies' velocities increase accordingly. The vertical analysis of the grinding disc's variation in height clearly reveals that the grinding bodies slide on a viscous fluid during operational mode. At the same time, a small vertical gap between the respective grinding body and the mill chamber bottom appears. [ABSTRACT FROM AUTHOR]

Abstract: Optimal process conditions for the delamination of multilayer graphene are realized with a vibratory disk mill, in which a highly viscous liquid consisting of sugar and graphite particles is comminuted. The conditions are investigated, in which shear forces are generated in the process in the vibratory disk mill. Graphene sheets with layer thicknesses of 2 – 10 layers are obtained. The multilayer graphene can be used in the production of lithium‐ion accumulators. [ABSTRACT FROM AUTHOR]

Abstract: A discrete population balance approach to model batch grinding is presented and used to simulate baryte grinding in a vibratory disc mill. The grinding kinetics used in the simulation are measured independently with the grinding rate depending on the particle size. A bimodal fragment size distribution of a single breakage event according to the Austin approach is used. The resulting model was solved by numerical integration and the results are discussed concerning accuracy and applicability. The experimental data are compared with the calculated results and show good agreement with the simulations. The breakage distribution is calculated for different particle sizes. This approach avoids the fitting of a large number of parameters to few experimental values, making the model more robust and allowing a wider range of applications, e.g. process optimization. [Copyright &y& Elsevier]