Production of briquettes using coconut and eucalyptus wastes

Produção de briquetes usando resíduos de coco e de eucalipto

ABSTRACT

This research analyzed the production and characteristics of briquettes composed of residues of Cocos nucifera and Eucalyptus pellita wood. A completely randomized design was used, having seven treatments and five repetitions per treatment. The treatments corresponded to waste percentages of coconut and eucalyptus residues as following: T1: 100% eucalyptus waste; T2: 20% coconut waste + 80% of eucalyptus waste; T3: 40% coconut waste + 60% of eucalyptus waste; T4: 50% coconut waste + 50% of eucalyptus waste; T5: 60% coconut waste + 40% of eucalyptus waste; T6: 80% coconut waste + 20% of eucalyptus waste; and, T7: 100% coconut waste. For the production of briquettes, 0.5% carboxymethylcellulose (CMC) was used as the binder. The mixtures were compacted under a load of 568 kgf cm^-² for three minutes. After pressing, the briquettes were air-dried to the equilibrium moisture of the environment and, then, analyzed for physical, chemical and energy characteristics. The data were analyzed through analysis of variance, correlations and hierarchical cluster analysis (HCA). The briquettes produced with 100% of C. nucifera residues had the highest equilibrium moisture content, high volatile matter concentrations, and low fixed carbon concentrations. The basic density, the apparent specific mass and the burning rate were not affected by the composition and by the equilibrium moisture of the briquettes.

Key words:
bioproducts and bioenergy; use of agroforestry residues; compaction and densification of biomass; biofuels