INFLUÊNCIA DA ADIÇÃO DE LIGNINA KRAFT NAS PROPRIEDADES DE PELLETS DE EUCALIPTO ; Influence of adding kraft lignin in eucalyptus pellets properties

The pellets are becoming an important renewable source of energy for industrial and domestic use. The consumer market is increasingly demanding in terms of product quality and this may be improved through the use of various additives, such as kraft lignin. The objective of this study was to evaluate the quality of eucalyptus pellets produced with the addition of different percentages of kraft lignin. The raw material used for production of pellets was wood with bark of an Eucalyptus grandis x E. urophylla clone, with approximately five years of age, obtained from commercial planting, and 10% of waste of eucalyptus harvest (tops, leaves and branches). Excluding the control (0% lignin) was added 1, 2, 3, and 5% kraft lignin, relative to the dry mass of raw material. The pellets were produced in a laboratory pelletizer with a horizontal circular array. The following properties of the pellets were evaluated: moisture content, gross and net calorific value, unit density, bulk density, energy density, ash content, length and diameter, hardness, mechanical durability and fines content. The addition of kraft lignin contributed to improving the pellets physical and mechanical properties, as regards the density, mechanical durability, fines and hardness. The addition of lignin caused the elevation of the levels of ash and moisture content of the pellets. It is concluded that addition of lignin to pellet production is feasible, since lignin is used with lower contents of ash and moisture. ; Os pellets vêm se tornando uma importante fonte renovável de energia para utilização industrial e doméstica. O mercado consumidor está cada vez mais exigente quanto à qualidade do produto e essa pode ser melhorada por meio da utilização de diferentes aditivos, como a lignina kraft. Assim, o objetivo desse trabalho foi avaliar a qualidade dos pellets de eucalipto produzidos com adição de diferentes percentagens de lignina kraft. A matéria-prima utilizada para produção de pellets foi madeira com casca de um clone de Eucalyptus grandis x ...