Fine-grained bulk materials with particle sizes below 40 microns such as silica, pigments, soot, cement, coal dust, clay, various ceramic powders and powders for the food industry often have a very large bulk volume, i.e. a low bulk density. Due to the high air entrapment and the large bulk volume, the further processing gets obstructed and high costs for pack-aging, storage and transportation occur.
The bulk volume of such fine-grained materials can be reduced up to 75% by the inter-action of mechanical pressure and vacuum.