Pelletizing of Colombian agro-industrial biomasses with crude glycerol

The effect of crude glycerol (G) on the pelletizing process and the quality of biomasses pellets were evaluated. Pellets were made of three types of agro-industrial biomasses typical of tropical countries: Sugarcane bagasse (SCB), Coffee Husk (CH) and Rice Husk (RH). Mixtures of water and glycerol were used as a binder. It was found that, with the addition of crude glycerin, the linkages between biomass particles for formation of pellets is made easier. However, this addition causes a reduction of the compaction degree since it acts as a lubricant between the biomass and the pelletization die, which produces the weakening of the solid to solid interaction. For CH and SCB particles, due to its shape and soft structure, pelletizing is not significantly affected by the biomass particle size variation, whereas in the case of small RH particles, the presence of a binder favors pelletizing. A brief dissertation about the aggregation mechanisms those were favored in each biomass type was carried out. A multi -criteria methodology was implemented by which it was possible to select the optimal conditions of pelletizing for each biomass. (C) 2018 Elsevier Ltd. All rights reserved.