Efeito da adição da antraquinona na pré-deslignificação com oxigênio no branqueamento e na qualidade da polpa kraft de eucalipto

• Ano de defesa: 2010
• Autor(a) principal: Silva, Mariléa Pinto da
• Orientador(a): Colodette, Jorge Luiz
• Banca de defesa: Gomide, José Lívio , Perissoto, Danyella Oliveira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado Profissionalizante em Tecnologia de Celulose e Papel
• Departamento: Qualidade da madeira; Tecnologia de celulose e papel
• País: BR
• Palavras-chave em Português: Antraquinona; Pré-deslignificação; Oxigênio; Branqueamento; Qualidade de polpa
• Palavras-chave em Inglês: Anthraquinone; Pre-delignification; Oxygen; Bleaching; Pulp quality
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS::TECNOLOGIA DE CELULOSE E PAPEL
• Link de acesso: http://locus.ufv.br/handle/123456789/5935

The Kraft pulp production has been highlighting in the world due to the great advantages that the process allows. Some studies have been showing that anthraquinone addition in cooking liquors results positive effects on process like yield increase, reduction of the number kappa and some gains in the physical properties of the pulp. The main objective of this work is to evaluate the effect of the addition of different amounts of anthraquinone in the oxygen delignification stage of pulp eucalyptus kraft. The impact on the bleachability and quality of the bleached pulp were evaluated too. The sample was collected in the outlet of washer before of oxygen delignification stage. The sample was divided in two fractions, the first one was washed with demineralized water and denominated "washed pulp" and the second one without washing was denominated "unwashed pulp". The pulps were characterized and treated on traditional conditions of the oxygen delignification, but with different anthraquinone dosages (0, 20, 30, 40, 50 and 60 g/t). The pulps washed and unwashed , without anthraquinone (0g of AQ) it was used as reference. The pulps treated with oxygen with 0, 40 and 60g/t of AQ were bleached by the DualD(EP)D bleaching sequence until 89,5% ISO of brightness. The effluent quality was evaluated generated in the bleaching. The bleached pulps were refined and evaluated as your physical and mechanical properties. The results show us that the washing of the pulp affects its strength characteristics. The anthraquinone doesn't influence in the efficiency, kappa, yield, hexenuronic acid of oxygen delignification stage. The COD of the pulp was reduced with the anthraquinone addition, mainly in the pulp unwashed. The viscosities of pulps washed and unwashed, showed an increase indicating that anthraquinone contributed to a larger retention of the carbohydrates. The final brightness of the washed pulp was reduced when compared with the pulp reference showing that anthraquinone influences in the pulp bleachability. The pulp unwashed showed positive effect in the brightnes during the bleaching. The use of anthraquinone in the oxygen delignification stage shows a reduction of chlorine dioxide consumption for pulp unwashed. The pulp washed it didn't show effect in the consumption of energy during the refining, while the pulp without washing increased the refining energy consumption when compared with the reference. The pulp unwashed treated with anthraquinone it resulted in larger levels of bulk when compared with the pulp reference, showing to be a suitable pulp for the Tissue paper production.