CARACTERÍSTICAS FÍSICO-QUÍMICAS E ENERGÉTICAS DE DUAS ESPÉCIES DE OCORRÊNCIA NO SEMIÁRIDO BRASILEIRO

• Published in: Ciência florestal 2012-01, Vol.22 (3), p.579-588
• Main Authors: Pedro Nicó de Medeiros Neto, Elisabeth de Oliveira, Leandro Calegari, Antonio Marcos César de Almeida, Alexandre Santos Pimenta, Angélica de Cássia Oliveira Carneiro
• Format: Article
• Language: Portuguese
• ISSN: 0103-9954; 1980-5098

The native vegetation from Brazilian Northeast has been explored and used intensively and inadequately asa source of energy and material for rural constructions. Now, it is recognized how important it is to get to know the characteristic of the wood produced by this vegetation. Thus, this study aims to provide information on the physicochemical and energetic characteristics of wood, carbonization yields and characterization of the charcoal from wood of Poincianella pyramidalis Tul. L.P.Queiroz and Handroanthus impertiginosus (Mart. ex DC.) Mattos. To meet the goal five trees from each species were cut down and randomly sample at Santa Barbara Farm, located in the municipality of São Mamede-PB. The trees were properly identified and transported to the Department of Forest Products Technology (STPF) at the Federal University of Campina Grande. Thirty centimeters sections were removed from each tree at 0 (base), 25, 50, 75 and100 % of the commercial height (trunk diameter > 5 cm). A 2.5 cm thick disc was removed from the median part of each 30 cm section, and each disc was subdivided in four wedge pieces, passing through the trunk pith. Two opposite wedge pieces were used to determine the basic density of wood, ant the other two pieces were put aside in order to carry out physical, chemical and energetic analyses, carbonization yields andcharacterization of the charcoal produced by the studied species. Basic density was determined according to the method of hydrostatic balance and to determine the average basic density of eachtree, the volume between sections of each disc was used as a weighting factor. After the air drying, thesamples intended for chemical analysis were transformed into sawdust and quantitative determinations of total extractiveswere performed, lignin, ashes, and the holocellulose content was estimated by difference. The samples intended for carbonization were processed into chips, and carbonized in an electric oven (furnace) for 5h30mim. Determinations of the yield of products of carbonization were carried out as well as physical and chemical properties of wood charcoal. In general, the studied wood showed similar physical characteristics.Regarding to chemical properties, Pau-d¿arco wood showed a higher lignin content (28.40 %), and there were not any significant differences among species for the holocellulose content The superior calorific power of Catingueira wood (4413.50 kcal.kg-1) showed the lowest values for wood (4413.50 kcal.kg-1) a