Powder Structure Control

Publication Reference: 
ARR-62-04
Author Last Name: 
Kohlus
Authors: 
Reinhold Kohlus
Report Type: 
ARR - Annual Report
Research Area: 
Particle Formation
Publication Year: 
2014
Publication Month: 
12
Country: 
Germany

1. Introduction

The earlier parts of the project were focused on the implementation of structure descriptors and determination of physical parameters of model granules and their correlation to structure parameters. The first results were intensified and finding checked for correctness.

Model granules were generated containing different size distributions of primary particles to achieve different internal structures. A series of bimodal particles size distribution of fine and coarse limestone particles were granulated with polyethylene glycol binder. Three dimensional X-ray micro tomography images of the model granules were recorded and used for further calculations of structure descriptors. The structure descriptors that were evaluated include volume and surface fraction, star volume, chord length distribu- tion and covariance function.

For the determination of physical properties the techniques established last year were applied. Mechanical strength is measured by single particle crushing and the dissolution or disintegration behaviour by conductivity measurements and online particle sizing respectively. The structural as well as the physical parameters provide results that are suitable to distinguish between differently structured granules.