Search for dissertations about: "Bleaching"

Showing result 1 - 5 of 108 swedish dissertations containing the word Bleaching.

  1. 1. On the Process Development of an ECF Light Bleaching Sequence for the Production of High Quality Softwood Kraft Pulp and Low AOX Formation

    Author : Sara Starrsjö; Juha Fiskari; Mikael Lindström; Olena Sevastyanova; Maria Boman; Peter Sandström; Mittuniversitetet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Chemical Engineering; Natural Science; Chemical Pulping; Softwood; Kraft Pulp; Bleaching; ECF light bleaching; Chlorine Dioxide; AOX formation; Delignification; Bleachability;

    Abstract : The aim of this work is to contribute to the process development of the ECF light bleaching sequence Q(OP)D(PO) by providing a better understanding of the bleaching of softwood kraft pulp. There are few published studies on this type of sequence, and more knowledge is needed on how to reduce environmental impact, improve cost-effectiveness and ensure a high pulp quality. READ MORE

  2. 2. Totally chlorine free bleaching of softwood kraft pulp : inhomogeneous ozone bleaching and particle elimination

    Author : Maria Ström; KTH; []
    Keywords : ;

    Abstract : .... READ MORE

  3. 3. The link between kraft cooking and bleaching : influence on ECF bleachabiblity and bleaching effluent parameters

    Author : Magnus Björklund; []
    Keywords : ;

    Abstract : The link between kraft cooking and bleaching was investigated, with the focus on how cooking kappa number, cooking conditions and pre-bleaching stages influence ECF bleachability and environmental parameters in the bleaching effluent. In one part of the study standard cooking conditions were used to produce birch and spruce pulps of different kappa numbers and then we studied how the AOX in the ECF bleaching effluent was affected by oxygen delignification, and hot acid stages. READ MORE

  4. 4. Zeolites in pulp bleaching

    Author : Kurt Dyhr; Luleå tekniska universitet; []

    Abstract : .... READ MORE

  5. 5. Free radical mediated cellulose degradation

    Author : Erik Johansson; KTH; []
    Keywords : free radicals; cellulose; polymer; average chain length; bleaching; TCF; ozone; degradation;

    Abstract : This thesis addresses the mechanisms involved in cellulosedegradation in general and Totally Chlorine Free (TCF) bleachingof pulp in particular. The thesis shows that the cellulosedegradation during high consistency ozone bleaching is explainedby free radical chain reactions. READ MORE