Abstract
In this study, energy densification and upgrading of fuel characteristics of wood chip via mild thermal treatment, so-called torrefaction, were conducted using tulip-tree (TUT; Liriodendron tulipifera). The calorific value and weight loss of TUT wood chips were significantly increased as the torrefaction temperature and time increased. However, the energy yield of torrefied TUT wood chips was decreased at severe torrefaction condition. During the torrefaction process, hydrophobicity of TUT wood chips was obtained. The higher hydrophobicity could give storage improvement to torrefied TUT wood chips. Furthermore, the grinding energy during the grinding of torrefied TUT wood chips was significantly reduced comparing to untreated TUT wood chips. Considering the grinding process is required for pelletizing of wood chips, it was thought that the torrefaction process could be advantageous for utilizing of lignocellulosic materials for energy source.