Estudo da branqueabilidade e da qualidade de polpas de Eucalyptus spp. de diferentes origens

• Ano de defesa: 2011
• Autor(a) principal: Martino, Daniela Correia
• Orientador(a): Colodette, Jorge Luiz
• Banca de defesa: Silva, Deusanilde de Jesus
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência Florestal
• Departamento: Manejo Florestal; Meio Ambiente e Conservação da Natureza; Silvicultura; Tecnologia e Utilização de
• País: BR
• Palavras-chave em Português: Composição química; Polpação Lo-Solids; Branqueabilidade; Polpas laboratoriais; Polpas industriais; Eucalyptus
• Palavras-chave em Inglês: Chemical composition; Lo-Solids pulping; Bleachability; Laboratory pulps; Industrials pulps
• 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/123456789/3086

The pulp bleachability can be affected by different factors, such as the chemical composition of the wood and the conditions used in the pulping process. This study aimed to identify the possible factors that affect the bleachability of eucalypt pulps from different sources. It was determined the density and the wood chemical composition of two pulp mills, designated A and B. The behavior of these woods was evaluated in relation to pulping performed in the laboratory and the parameters of unbleached laboratorial pulps were compared with the parameters of unbleached industrial pulps. Likewise, the parameters of the laboratorial and industrial pre-delignificated pulps were compared. The pulping and bleaching were carried out at the same conditions. The basic density of the wood A was 480 kg/m³ and B was 473 kg/m³. The carbohydrate contents of the wood were also similar. The variation between the brightness values of the unbleached laboratorial pulps were 0.3% ISO and the variation between the brightness values of the unbleached industrial pulps was more than 4.0% ISO. The bleachability of the industrial pre-delignificated pulp from the factory A was higher than the factory B which showed a lower initial brightness. The main factors affected the studied pulp bleachability were the brightness and the initial hexenuronic acid content resulting from the industrial cooking. The industrial pulp B showed a significantly lower tear index than the industrial pulp A.