Potential of mild torrefaction for upgrading the wood energy value of different Eucalyptus species

• Autor(a) principal: Araújo, Solange de Oliveira
• Data de Publicação: 2018
• Outros Autores: Neiva, Duarte M., Carneiro, Angélica de Cássia, Esteves, Bruno, Pereira, Helena
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.5/16045
• topic: Eucalyptus; torrefaction; high heating value (HHV); thermogravimetric analysis (TGA); elemental composition

Torrefaction is a promising pre-treatment for improving the fuel quality of biomass. This study examined the effect of a mild torrefaction (from 160 to 230 C) on the heating value, elemental composition, and thermogravimetric analysis of wood from eight Eucalyptus species (E. botryoides Sm., E. globulus Labill., E. grandis W.Hill ex Maiden, E. maculata (Hook.) K.D. Hill & L.A.S.Johnson, E. propinqua Maiden Deane, E. rudis Endl., E. saligna Sm., and E. viminalis Labill.). The higher heating values (HHV) increased from the initial average of 19 MJ kg1 to 21 MJ kg1 in the torrefied samples. The carbon content increased from 48.2% to 53.3% and the C/O ratio from 1.08 to 1.35. The torrefied wood samples showed more thermal stability with a shift of the mass loss peaks to higher temperatures and a higher residual mass at 450 C of 36%, in comparison to 30% of the untreated samples. Torrefaction concentrated the biomass samples in the more energetic and thermal resistant components and decreased their sulfur and chlorine content, leading to a better combustion performance. The wood of the eight Eucalyptus species had a similar behavior and showed quality improvement. Therefore, torrefaction showed potential as a pre-treatment for eucalyptus biomass fuel improvement