Comparative study on the compression characteristics under mechanical
and gas pressurization
Abstract
Powder compression is essential in the storage and transportation
processes. The compression characteristics of pulverized coal, rice husk
and lignocellulose were compared under mechanical and gas pressurization
respectively. The experimental results showed that the descending order
of relative packing density was lignocellulose > rice husk
> pulverized coal under mechanical pressurization, while an
opposite trend was observed under gas pressurization. The effect of
cohesion properties on compression results, such as inter-particle
adhesion force and powder bed cohesion, was also investigated. For
mechanical pressurization, the powder bed of cohesive biomass had higher
void fraction, which was directly linked to larger relative packing
density. On the contrary, gas permeated easily into the biomass powder
bed, and the lower pressure drop decreased the compression capacity of
gas pressurization. In addition, a model for predicting the relative
packing density was proposed with an error of ± 5%.