Flow Properties of Bulk Material as a Product of the Beech Chips Grinding

Abstract

The article deals with the various methods of characterization and evaluation of the shape and dimensions of particles that are a product of grinding the beech chips in a knife mill. The speed of rotor with knives and two types of die were tested parameters. The product that was obtained by grinding has non-isometric particles. The main problem how to evaluate the particle size distribution for such materials is the choice of the characteristic size and the method for determining the particle size distribution. At present it is possible to use the modern, optical dynamic methods, based on particle visualization. The results from the both milling methods are processed into the various graphical dependencies, taking into account the shape of the particles and the particle size distribution. However, the particle size distribution also has an effect on the flow properties of the bulk materials. A special rheometer for measuring the flow properties of powders is used. The results of measurements are used for characterization the influence of the grinding process parameters on the flow properties of the product.