WOOD QUALITY OF FIVE <em>EUCALYPTUS</em> SPECIES PLANTED IN RIO GRANDE DO SUL, BRAZIL FOR CHARCOAL PRODUCTION

Abstract

The objective of this study was to evaluate the wood quality of Eucalyptus benthamii, E. dunnii, E. grandis, E. saligna and E. urophylla x E. grandis from seven-year-old commercial plantations in the state of Rio Grande do Sul for charcoal production. The wood properties determined for each species were basic density, structural chemical composition and high heating value. The materials was carbonised at 450 °C in a muffle furnace with a heating rate of 2 °C min^-1, from 100 °C up to 450 °C for 30 minutes. The yields of charcoal, pirolenous liquor and non-condensable gases were collected. Charcoal properties evaluated were fixed carbon, volatile and ash contents and high heating value. Yields of fixed and energy carbon were also calculated. A completely randomised design was used to evaluate the experiment. The results showed that all the species had similar charcoal quality, but differing in the structural chemical composition of the wood, resulting in differences in gravimetric yields. The species E. benthamii was superior compared to the others, thus, it is the most useful for charcoal production.