Torrefaction of Fast-Growing Colombian Wood Species

Abstract

The aim of this paper is to report fuel properties and torrefaction behavior of woody biomass from the Colombian highlands. Four wood species (Eucalyptus grandis, Pinus Maximinoi, Pinus patula, and Gmelina arborea) were selected due to their potential for expansion as bioenergy crops. Torrefaction of these feedstocks for the production of pellets for both domestic and international markets is a promising way to take advantage of these resources. Herein we report the impact of torrefaction temperature (between 200 and 300 °C) on the proximate and ultimate composition, heating value, thermal stability, and volatile products of the resulting solids. Although, all samples studied have similar volatile contents (70 wt%), heating value (~ 18.7 MJ/kg), and ash content (< 1 wt%), their thermal behavior during torrefaction is different. Our results confirm that the fuel properties of the materials studied have been improved by torrefaction. Py/GC-MS studies of torrefied materials suggest that the torrefaction conditions studied do not affect the structure of cellulose and lignin fractions; thus, the yield and composition of volatile products was not dramatically affected by the torrefaction conditions. The resulting materials could be good feedstocks for centralized pyrolysis based bio-refineries.