Sökning: "chlorine-free bleaching"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden chlorine-free bleaching.

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

    Författare :Maria Ström; KTH; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  3. 2. Some aspects on TCF-bleachability of softwood alkaline pulps

    Författare :Karin Sjöström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bleachability; chlorine-free bleaching; softwoods; kraft pulps; alkaline sulfite pulps; oxygen; hydrogen peroxide; ozone; hydrogen sulfide ion; hydroxide ion; temperature; sodium ion.; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : The bleachability of softwood oxygen delignified pulps has been studied, i.e. the ease (requirement of bleaching chemicals) with which the pulps can be brightened to a target brightness in totally chlorine free (TCF) bleaching stages, including hydrogen peroxide, ozone and chelating agent stages. LÄS MER

  4. 3. Free radical mediated cellulose degradation

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

    Sammanfattning : 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. LÄS MER

  5. 4. Fibre surface properties of kraft pulp : The influence of wood raw material, bleaching and storage

    Författare :Gerd Wäne; Ulf Germgård; Pedro Fardim; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Sammanfattning : The aim of this thesis was to study the fibre surface properties of Birch (Betula ssp.), Eucalyptus (E. urograndis and E. globulus) and Spruce (Picea Abies) pulps bleached using two different methods: ECF (Elementary Chlorine Free) and TCF (Totally Chlorine Free). LÄS MER

  7. 5. Anaerobic digestion in the kraft pulp and paper industry : Challenges and possibilities for implementation

    Författare :Eva-Maria Ekstrand; Bo H Svensson; Annika Björn (Fredriksson); David Bastviken; Jukka Rintala; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pulp and paper; anaerobic digestion; fibre sludge; activated sludge; condensates; bleaching wastewater; wastewater treatment; methane; degradability; nutrient recirculation; Pappers- och massa; anaerob nedbrytning; fiberslam; aktivt slam; kondensat; vattenrening; metan; nedbrytbarhet; näringsåterföring;

    Sammanfattning : The pulp and paper industry is a large producer of wastewater and sludge, putting high pressure on waste treatment. In addition, more rigorous environmental legislation for pollution control and demands to increase the use of renewable energy have put further pressure on the pulp and paper industry’s waste treatment, where anaerobic digestion (AD) and the production of methane could pose a solution. LÄS MER