The addition effect of binders on the durability (PDI) of biomass pellets

Abstract

The direct use of agricultural and forestry waste as energy source is not efficient since they generally
have low calorific value and density, the resides compaction can be a solution to those problems. The
compacted residues are denser than the unprocessed waste, because of that, it has higher energy per volume
unit. The objective of this work was to evaluate the quality of pellets manufactured from coconut fiber
and cotton residues; both collected in the state of Córdoba-Colombia. It was made twelve experimental
pellets, testing three different binders (corn, cassava and banana) in two different percentages (10 and
30%) and two types of pellets were made without the addition of any binders. After two weeks, the PDI
(durability) for all treatments was determined according to the ASABE 269.4 standard. The moisture
content and particle size in the materials were also determined. The PDI of pellets produced without
binders was compared with the PDI of pellets with binders. The results showed that both pellets had
PDI higher than 97.95% and statistically there were no significant differences when the type of binder
varied. It was therefore, possible to produce pellets with good quality without the use of binders, using coconut fiber and cotton residues only, with particle sizes of less than 2 mm (10 mesh) and moisture
content between 10 and 15%.