The valuation of the Eucalyptus grandis x Eucalyptus urophylla hybrid wood through the production of small dimension sawnwood, pulpwood and fuelwood

Author(s)

Alexandre Monteiro de Carvalho

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2000-08-28
• Advisor: Marcio Augusto Rabelo Nahuz

Abstract

A 7-year plantation of Eucalyptus grandis x Eucalyptus urophylla hybrid established in the vicinity of Mogi Guaçu/SP and managed to supply raw material to the pulp and paper industry was harvested in a differentiated way to produce wood for multiple purposes. A one-hectare sample plot was randomly selected within a commercial plantation, which was thoroughly inventoried and the wood graded into three fractions for different uses (Fraction I - boards and "clear blocks" sawnwood; Fraction II - pulpwood and Fraction IH - fuelwood). Parameters for field grading of the wood were defined according to the conditions required at the testing sites. In addition to yield analysis and product quality, a research was conducted among producers and researchers active in the market of plantation sawnwood products. This research aimed at identifying specifications and prices of sawnwood, especially the so-called "clear blocks", small dimension sawnwood free of defects, produced for the export market. The study placed special emphasis on Fraction I - sawnwood - since potentially, it carries most added value. On a pilot scale, the study produced boards and "clear blocks" sawnwood, woodpulp or cellulose, and fuelwood. The combined yields of these products were analysed in comparison with the results obtained in a standard operation aimed solely at the production of pulpwood. The analyses of the pulp production material showed high quality and yield results, yielding about 54% of unbleached pulp. The sawnwood production yielded 39,71% of dried sawnwood and 29,98% of "clear blocks". The combined production of cellulose, fuelwood, sawn boards and "clear blocks" was compared to the standard production of pulp in a simulated market operation, by using the data obtained in the tests and that supplied by the sawnwood producers. The results favour the diversification of products as an important alternative in situations where the pulp market price is low. The predictable growth of the market for eucalyptus sawnwood indicates a great potential for initiatives in the management and processing of wood produced in multiple use systems. (AU)