Chemical characterization of eucalyptus SP. residues from short-rotation forests for bioenergy production

Abstract

The use of biomass resources to generate energy has been growing as renewable alternative, foremost because of their promising properties. Nowadays, one of the newest alternative resources under study is the biomass from shortrotation forests. However, such process lacks development to be used in commercial scale in Brazil, despite its positive perspectives. The aim of the present study is to chemically characterize Eucalyptus sp. residues, in order to find their potential applicability as sustainable fuel. The material was collected in short-rotation forests in Taiobeiras, Minas Gerais State. Two treatments were tested, namely: residues collected in the harvester (T1) and 40-day-dried soil residues (T2). Firstly, the volatile matter and the ash content were analyzed in triplicate to determine the fixed carbon content. The results were 1.35%, 79.35% and 19.3%, in T1; and 1.30%, 80.60% and 19.2%, in T2, respectively. The extractive levels were 15.88%, in T1; and 12.37%, in T2. The lignin values reached 17.12% and 20%, in T1 and T2, respectively. The holocellulose and α-cellulose levels were recorded and the hemicellulose level was found using the difference between the holocellulose ad α-hellulose values. The holocellulose reached 65.94%, T1 and 63.34%, in T2; Whereas the α-cellulose presented values such as 40.64%, in T1; and 36.22%, in T2. Therefore, the hemicellulose content was 25.30% and 25.12%, in T1 and T2, respectively. Lastly, the calorific power levels were 18132.5 J/g and 18175.0 J/g, in T1 and T2, results that may be related to the chemical composition of short rotation timber.