Influência das dimensões da biomassa estocada de pinus taeda L. E eucalyptus dunnii maiden na qualidade do combustível para geração de energia

Abstract

The objective of the present study was to determine the influence of the size and shape of the biomass on the changes in its properties during storage, aiming its use on energy production. The experiment was conducted in Lages - Santa Catarina State, Brazil, from October 2003 to February 2005. Logs with bark of Pinus taeda L. and Eucalyptus dunnii Maiden, and Pinus spp edge, were stored in piles for six months. Samples for analysis were collected in freshly harvested state, with two, four and six months of storage. Four batches, collected and stored were used according to the seasons of the year, remaining in storage from October to May, from January to August, from May to November and from August to February. The properties evaluated were: moisture content in wet basis, gross and net calorific value and ash content. The shape and size had greater influence on the moisture content and on net calorific value. The pine edge suffered greater loss of moisture content, higher gain and lower gross calorific value and lower ash content during storage. This material was also the most heterogeneous, with respect to changes occurred during storage. The logs of Pinus had the lowest moisture loss and lower energy gain. In general, and considering the most important properties for generating energy, the size of the material had greater influence than the species on the behavior of biomass storage.