Laboratory analysis of powder segregation
Delft Solids Solutions now offers testing the tendency of powders towards segregation
Considerable efforts are often devoted to the mixing of several different species of powders (of various sizes, shapes and densities) in order to have a homogeneous mixture of the intermediate or final product. Nevertheless, a well-mixed system may segregate during handling, e.g. when discharging into a bin or big-bag, transportation in a truck or pipe-line, but this could also occur when loading the powder in e.g. a tablet press for production of pharmaceutical tablets. Surprisingly, this phenomenon is often overlooked or not adequately tackled.
Prediction and quantification of this segregation phenomenon can now be executed in the Delft Solids Solutions laboratory. The fluidization segregation tendency of powders is assessed in accordance with ASTM D 6941 standard. In this segregation test, a fixed volume of a representative powder sample is fluidized and collected in different fractions. Subsequently, typical characteristics (e.g. particle size or density) of the top and bottom fraction are determined in order to quantify the segregation tendency of the sample. This experimental approach improves the understanding of how transportation and handling efforts can lead to the often undesired segregation of powders.
