This paper’s goal was to select methods and a calibration procedure which would lead to the determination of relevant parameters of a discrete element method (DEM) and virtual material creation. Seven particulates were selected with respect to their shape (spherical and non-spherical), size and density. The first calibration experiment involved “packing test” to determine the shape accuracy and bulk density of virtual packed particulates. The series of simulations were compared with real experiments, and the size, shape and density of virtual particles were optimized. Using three apparatuses, the input parameter values were experimentally determined for a contact model that defines the behavior of particulates in DEM simulations. The research part of the paper examines the influence of factors such as particle number; pile formation method; and the method of evaluation of the angle of repose on the process of the calibration of virtual material. The most reproducible results were achieved by the “pilling” method and by the rotating drum—both evaluated by the geometric method. However, it is always advisable to make an overall visual comparison of the slope shape between the calibration simulation and the experimental curves. The bowl’s diameter to particle size ratio should be greater than 25, and the calibration experiment should contain approximately 4000 particles to ensure representative results during angle of repose calibration experiment.

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The process of homogenization of particulates is an indispensable part of many industrial processes, and, therefore, it is necessary to pay a special attention to this area and develop it. This paper deals with a complex study of homogenization of particulate matters in a rotary drum in terms of shape, size, and density of particles. In addition, the influence of operating parameters, such as drum filling capacity, rotational speed, and drum filling pattern are also investigated. Studies of reproducibility of discrete element method simulations, effects of rotary drum sizes or effects of drum volumetric filling to the mixture homogeneity index were also carried out. In general, the least satisfactory values of the homogeneity index resulted from the mixing of particles with different densities. The dominating factor of homogenization was the drum filling-up degree. The course of the homogeneity index in 140, 280, and 420 mm drums was very similar and after five revolutions of the drum, identical values of the homogeneity index were achieved for all the drum diameters. The optimal drum filling-up degree is at 40–50% for the spherical particles and 30–40% for the sharp-edged particles. The repeatability of simulations showed the maximum relative standard deviation of the homogeneity index at 0.6% from ten simulation repetitions with the same parametric conditions.

This paper presents the use of new modern methods for the research of movement of material on a belt conveyor. One of the innovative methods is Particle Image Velocimetry (PIV), which was used to scan and assess the two-dimensional vector field of speed of particles on the belt conveyor. Outputs from PIV were compared to simulations of the same transport process. These simulations were performed using the Discrete Element Method (DEM). Four transport speeds of material were assessed for a real and simulative belt conveyor model. Software tracking of particle movement was used to determine and compare the trajectories of paths of particles leaving the belt conveyor drum. Validation of the DEM simulation of material movement over a belt conveyor drum using PIV provided acceptable results in the area of particle speed fields. Comparison of the particle path trajectory corresponds to the preliminary hypothesis which leads to calibration of the DEM simulation. The results and assessment of this paper were created based on validation.

The knowledge of a grinder structure, its performance parameters and characteristics of biomaterials breakage are crucial for this research whose aim is to determine the dependencies between performance parameters and comminution indicators. The aim of this study is to investigate the relationships between multi-disc mill performance parameters such as discs angular speed, batch dosing speed and comminution characteristics: power consumption, specific energy consumption, throughput and size reduction ratio. To achieve these goals, an experiment was conducted on a five-disc mill with a special monitoring system. The research program was established, with disc angular speed at different configurations and different batch dosing speeds. The results show that power consumption, specific energy consumption and size reduction ratio depend on the total increase in angular speed of discs SΔω in such a way that an increase in SΔω causes an increase in the abovementioned comminution indicators. In turn, an increase in batch dosing speed W causes an increase in throughput. The fitting curves of comminution indicators in dependence of selected performance parameters are also presented in this study.