Luis E. Arteaga-Perez
University of Concepcion, Chile
Title: Energy valorization of residues from Quercus sideroxyla and Pinus duranguensis: Focus on Torrefaction
Biography
Biography: Luis E. Arteaga-Perez
Abstract
In this study, the energy valorization of both Quercus sideroxyla and Pinus duranguensis, is assessed. These species were selected due to their importance in the Mexican timber industry and based on the high generation of residues from its exploitation (10.75 tonne/ha). Here we analyzed the torrefaction as a pretreatment to improve the fuel quality of residues. With that end, we focused on (i) compositional and elemental analyses, (ii) the thermal decomposition through TGA-MS and (iii) the evaluation of torrefaction in a lab-scale facility. Results from thermogravimetric decomposition of both species exhibited the typical performance of lignocellulosic materials, with two reaction zones (active and passive pyrolysis). The kinetics of these zones was studied through isoconversional approaches (OFW and Starink). Values of activation energies for hemicellulose degradation (137-150 kJ/mol), obtained from both methods, were similar. Torrefaction of both wood samples was carried out at 15-30 min (residence time) and at four temperature levels (220-250-280-290 ºC). Effect of temperature on energy yield was higher than that of residence time, it produced an average yield drop from about 92% (at 220 °C) to 74% (at 290 °C. The reduction of energy yield for pine was approximately 5% lower than that of quercus, which could be attributed to its higher content of xylan. The heating value of torrefied solids increased by a factor of 1.31 (quercus) and 1.22 (pinus), respectively. Considering the resources availability and the effect of torrefaction on its fuel properties, this is an interesting alternative to valorize the forest residues from Durango.