Resolving lateral segregation effects of static blenders

To date static blenders have mainly been used for mixing fluids, but recent research has shown the potential of static blenders for blending powders and granular materials as well. A problem when using a static blender in conjunction with powders and granular materials is trajectory induced segregation at the output of the blender. In order to evaluate the blending process two granular materials exhibiting extreme particle densities and sizes have been discharged into a static blender. The blend is collected in a radially compartmentalised receiving container and the blend composition of each compartment is then analysed. This paper presents a simple counter measure to reduce the effect of trajectory induced segregation. In addition this research has shown that, contrary to expectations, an increased number of blending stages does not necessarily bring improvements in homogeneity of the output stream. The results presented in this paper are of special interest to anyone blending powders and granular materials in an industrial environment