Biorrefinaria da madeira de eucalipto associada à indústria de celulose e papel

• Ano de defesa: 2013
• Autor(a) principal: Longue Júnior, Dalton
• Orientador(a): Colodette, Jorge Luiz
• Banca de defesa: Silva, Vanessa Lopes , Santos, Fernando Almeida
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Ciência Florestal
• Departamento: Manejo Florestal; Meio Ambiente e Conservação da Natureza; Silvicultura; Tecnologia e Utilização de
• País: BR
• Palavras-chave em Português: Biorrefinaria; Eucalipto; Xilanas
• Palavras-chave em Inglês: Biorefinery; Eucalyptus; Xylans
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS
• Link de acesso: http://locus.ufv.br/handle/123456789/591

Eucalypt woods have been a biomass source largely used for the pulp and paper industry, charcoal and wood solid products, etc. With the emergence of the modern concept of biorefineries where wood and other biomass have been seen as potential replacements for petroleum and its derivatives, research on eucalyptus wood began to focus on alternatives with potential to generate higher value products of this important biomass for Brazil and for all the world. This thesis deals with a number of potential alternatives that use eucalyptus wood that still require further scientific studies, with special attention to better efficiency of the use of hemicellulose. So, this thesis was developed in six chapters aiming to address the issue of biorefinery associated with alternative uses of eucalyptus wood. Chapter 1 presents a literature review on the current uses of eucalyptus wood, especially in Brazil, focusing on its main advantages and disadvantages. Chapter 2 addresses the use of Eucalyptus grandis wood in the production of thermomechanical thermo ground wood (TGW) replacing wood of Pinus patula tree. In Chapters 3 and 4 the biorefinery of eucalyptus hemicellulose is discussed in a in depth study of the integration process of pulp and paper by the management in these polymers plant. In chapter 5 were evaluated methodologies showing how to remove hemicellulose from the Eucalyptus urograndis hybrid previously the kraft pulping process, in order to add more value of these polymers. In chapter 6, which was held at the North Carolina State University during the DS sandwich program when methodologies for characterization and utilization of hemicellulose extracted for Eucalyptus globulus and sweetgum for bioproducts production was investigated. The results of this study led to the following main conclusions: forest species of the genus Eucalyptus are very important for the forestry sector, mainly for the Pulp and Paper industry seeking to increasingly use the components of eucalypt woods entirely within biorefinery concept (chapter 1); the treatment of Eucalyptus grandis TGW raw rejected with alkali (50 kg/odt), followed by controlled refining (10 minutes) significantly improves the strength properties of the resulting pulp, but has a negative effect on brightness and the bulk of the pulp (chapter 2). The conversion of kraft pulp in dissolving pulp is possible treating the kraft pulp with cold alkali using white liquor during the CCE stage, also, showing to be possible the production of dissolving pulp with less than 5% of xylans achieved when 550 kgEA/t in 10% of consistency, at 20 °C and 15 minutes was used. In this case, approximately 4.2% of xylan dissolved in the CCE liquor could be recovered (Chapter 3). The possibility to integrate the fiber lines showing the feasibility of the integrated production of pulp paper grade and dissolving pulp, since changes and investments were made in production lines. The production of pulp paper grade with higher xylan content after refining (3%) when MPE extracted from the CCE stage was used in the oxygen stage and this pulp can be easily refined. The bleaching of dissolving pulp only assessed the reference pulp quality (viscose grade) when peracetic acid was used as the last bleaching stage (Chapter 4). The extraction of xylan with hot NaOH from wood was inefficient, reaching 42% of 4-O-methylglucuronoxylans. However, it was shown the importance of the increasing NaOH concentration in the efficiency of xylan removal and its effect on subsequent cooking, especially in the reduction of yield (Chapter 5).Finally, alkaline treatment of wood chips with 50% NaOH was more efficient when sweetgum chips were used rather than eucalyptus chips, allowing recovery of 4.3% of biomass with predominant hemicellulose fraction (degree of polymerization 250 and thermal and chemical characteristics similar to the commercial xylans) as well as recovery of ethanol used for precipitation of xylans (Chapter 6).