Modification of a mill deopdd sequence: Improvement in the d stage for combination of ozone (z) and chlorine dioxide (d) on the (zd)eopdd sequence of softwood kraft-oxygen pulp

• H MILLAR ^[1] ; J RUIZ ^[1] ; J. FREER ^[1] ; J BAEZA ^[1]
  1. [1] Universidad de Concepción

     Universidad de Concepción

     Comuna de Concepción, Chile

     
• Localización: Journal of the Chilean Chemical Society (Boletín de la Sociedad Chilena de Química), ISSN-e 0717-6309, ISSN 0366-1644, Vol. 48, Nº. 1, 2003, págs. 29-33
• Idioma: inglés
• Enlaces
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• Resumen

  • In this study, the (ZD)EopDD bleaching sequence for a softwood pulp was compared with the conventional ECF reference sequence DEopDD used in the mill. A Pinus radiata kraft-oxygen pulp was treated with a (ZD) stage at 0.3% ozone and 0.5% chlorine dioxide charges. The best result was reached with the (ZD) process when O3 and ClO2 were added sequentially at high consistency. The use of ozone allowed a 43% reduction in the use of chlorine dioxide. With the (ZD)EopDD sequence a 90%ISO brightness bleached pulp was obtained, having acceptable mechanical properties, which are comparable to that generated by the DEopDD s