CHARCOAL CHARACTERISTICS OF AN Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S. T. Blake CLONE

Abstract

This work determined the variability existent in the characteristics of the charcoal of a clone of Eucalyptus grandis x Eucalyptus urophylla at 6 years of age, planted in the municipal district of Martinho Campos, MG. The trees were distributed into three diameter classes and the sampling consisted of the removal of 2,5 cm thick disks at 2%, 10%, 30% and 70% of the commercial height, besides one at 1.30m from the soil (DBH) and starting from this point meter by meter until the commercial height. Samples were taken along the disk radius, considering the two sides in relation to the core. The samples were carbonized in an electric laboratory oven and the yield and the quality of the produced charcoal were determined. It was concluded that for the first carbonization, the diametric class significantly  influenced the gravimetric yield in wood charcoal and in pyroligneous liquid, the ash level of the charcoal produced. The non-condensable gas yield, the level of volatile materials and that of fixed carbon were not influenced by the diametric class. For the second carbonization, the gravimetric yield of charcoal increased from the bark to the pith, in all diametric classes and there was a reduction for this characteristic with the decreasing diametric classes and the apparent relative density values tended to increase from pith to bark in all diameter classes.