Aperfeiçoamento da sequência O/OD*(EP)DP para branqueamento de celulose kraft de eucalipto

• Autor(a) principal: Pimenta, Leonardo Mendonça
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5897
• topic: Aperfeiçoamento; Sequência O/OD*(EP)DP; Branqueamento; Celulose kraft de eucalipto; Improvement; O/OD*(EP)DP sequence; Bleaching; Eucaliptus kraft cellulose; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS::TECNOLOGIA DE CELULOSE E PAPEL

A eucaliptus kraft pulp of a Brazilian mill, extracted from the first washing stage before oxygen delignification, was bleached at more than 50 different bleaching conditions with the target to reach the optimum cost. Considering the O/OD*(EP)DP sequence, the best result was reached carrying out D* stage with soft conditions, preserving hexenuronic acids in the pulp and minimizing the chlorine dioxide consumption by products from its hydrolysis (furan carboxylic acids). Twenty one percent cost savings, in relation to current mill conditions, were achieved using pH 4,5, kappa factor 0,16 and 70 ºC temperature at D*stage, pH 10,3 and 5,5 at (EP) and D1 stages, respectively. Strength properties of this pulp were not significantly affected if compared with reference pulp produced under current mill conditions. The OX and AOX contents of this pulp were significantly reduced in relation to the reference. When applied at the mill, these optimum conditions were responsible for reducing 5 kg/adt active chlorine consumption.