Physico-chemical properties of wood pellets from forest residues

The study investigated the physical, chemical and combustion properties of wood pellets from forest residues. Wood shavings from mixed Dipterocarpaceae species and branch wood of Gmelina arborea and Leucaena leucocephala were used as feedstock. Ultimate, proximate, elemental and combustion analyses were performed to assess pellet quality in accordance with DIN 51731 (1996) for compressed solid fuel. In general, forest biomass used in this study formed pellets that were homogenous with uniform size and shape. Moisture content, particle density, bulk density and abrasion resistance were all within guiding values of the standard. Pellet samples used in this study showed relatively low levels of ash forming elements and heavy metals with calorific values suitable for industrial and residential heating applications. Combustion analyses of pellets from shavings and branch wood also showed that these materials burned freely and continuously while maintaining their integrity during the burning cycle. Low levels of pollutant emissions were detected when pellets were burned from biomass samples used in this study