Anelamento e vaporização de toras visando otimização do processo de secagem da madeira eucalipto

Abstract

RESUMOO objetivo deste estudo foi avaliar a qualidade da secagem da madeira de Eucalyptus pellita previamente submetidas aos processos de anelamento e vaporização. A metodologia baseou-se na hipótese de que o uso das técnicas conjuntas de anelamento e vaporização diminuiriam os defeitos apresentados pela madeira serrada após a secagem. Doze árvores de Eucalyptus pellita foram coletadas e seccionadas em toras de três metros de comprimento. A metade destas passou pelo processo de anelamento radial e a outra metade foi vaporizada a 82 ºC. Após o desdobro, as tábuas foram submetidas a secagem em estufa convencional utilizando um programa considerado severo para a madeira de eucalipto. O objetivo disso foi potencializar o aparecimento de defeitos e assim, analisar o efeito dos tratamentos na minimização dos mesmos. Pode-se concluir que a realização do anelamento e aplicação da vaporização melhorou a qualidade da madeira serrada sem comprometer o rendimento final. Os defeitos de encurvamento, arqueamento e encanoamento foram considerados leves, apesar da secagem severa.Palavras-chave: Defeitos de secagem, qualidade da madeira, secagem severa Log steaming and ringment for optimization of eucalyptus wood drying process ABSTRACTThe aim of this study was to evaluate the quality of lumber Eucalyptus pellita previously subjected to annealing processes, steaming and drying under severe drought. The methodology used was based on the hypothesis that the use of combined techniques girdling and spraying would reduce the defects in the lumber after drying. Twelve trees of Eucalyptus pellita were collected, sectioned into three logs 3.0 meters where half of the total spent by annealing (1/3 radius) and the other half were steamed until the center of the logs reached 82ºC. Then the logs were split into boards by successive cuts tangential using a horizontal band saw. The boards went to a conventional drying oven, where a drying program considered severe for eucalyptus wood applied. After drying, it was determined the main defects occurred on tablets, such as cracking index, boards crook, boards bow, cup boards and presence of collapse. Overall, it was concluded that the completion of ring and application of spray improved the quality of lumber Eucalyptus pellita without compromising the final yield of the material. Defects in curving, arching and curling were considered mild, despite the severe drying.

Water Flow Evaluation in Eucalyptus and Corymbia Short Logs

“…Several studies have evaluated the water outlet of the Eucapyptus, mainly in lumber (Barbosa et al, 2005;Jankowsky & Santos, 2005;Klitzke & Batista, 2010;Sepulveda-Villarroel et al, 2015;Latorraca et al, 2015). Publications on the drying of Eucalyptus logs began in the 1980s, with studies of the effect of time on wood drying (Vital et al, 1985).…”

RADIAL CLUSTER OF Eucalyptus grandis BOARDS SUBMITTED TO THE CONVENTIONAL DRYING PROCESS

“…These trees, before being felled, at a height of 1.30m, were girdlined with a chainsaw. After felling, to reduce cracking at the ends of the logs, girdling (continuous incisions with 1/3 depth of its radius) was also performed along the trunk at heights corresponding to 3.70, 6.10 and 8.70 m, according to the methodology described by Latorraca et al (2015). These logs were transported and stored in the sawmill park and cut into 2.0 m long short logs, eliminating 20 cm of wood located around each girdling.…”

“…In the 132 boards, the natural defects were evaluated qualitatively and the drying defects were evaluated quantitatively, based on the methodology described by Latorraca et al (2015) and Lópes et al (2016).…”

Efeito da densidade e da cor na molhabilidade da superfície de madeiras de eucalipto

“…a secagem e a presença de tensões de crescimento têm sido reduzidos com os avanços tecnológicos (LATORRACA, et al, 2015;TEIXEIRA, et al, 2009). Entretanto, segundo Silva et al (2005Silva et al ( , 2009, os poucos estudos sobre este material ainda dificultam o uso de madeira sólida.…”