Bulk Density of Granular Materials During Processing

Bulk density is an important process parameter for machines that transport, feed or process granular materials. Certain process variables have been shown to increase bulk density, such as the channel geometry at machines with rotational helical elements, the shape, dimensions and dimension distribution of granules, pressure, temperature, and vibration of the granular layer. The effect of the random fluctuation of the bulk density shows off in the flow rate variation that may affect product quality being therefore necessary to reduce possible fluctuations of bulk density. Experimental data was analyzed to evidence the influence of vibrations over bulk density and flow rate. The experimental results showed a significant increase of flow rate as a consequence of the vibration of the granular assembly in the feeding zone of the transport or processing machine.