Production of Chips from Logging Residues and Their Quality for Energy: A Review of European Literature

Abstract

Wood chips from logging residues are a renewable solid fuel that has become widely used in the energy sector. The current work presents a review of European papers on various aspects of wood chips production published in the years 2005–2018. The effects of the comminution method on the quality and energy parameters of the resulting wood chips were analysed. Most authors identified terrain and roadside chipping as the optimum technologies from the energy viewpoint. Furthermore, seasonal changes in the moisture content of wood chips have implications for their ash content and calorific value and determine the annual patterns of supplies to energy plants. In general, logging residues should be chipped approximately five to seven months after harvesting and delivered over economically feasible distances, which have increased in recent years due to the large dispersion of forest areas and energy plants. In a number of cases, logging residue chips did not meet the quality specifications contained in the relevant ISO standards, which may result in technological problems with their burning, especially in small to medium energy plants.