Sökning: "Residual phase lignin"

Hittade 3 avhandlingar innehållade orden Residual phase lignin.

  1. 1. Some factors affecting the amount of residual phase lignin during kraft pulping

    Detta är en avhandling från Stockholm : KTH

    Författare :Mikael E. Lindström; KTH.; [1997]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Deligniflcation; Residual phase lignin; Hydrogensulfide ion; Hydroxide ion; Polysulfides; Ionic strength; Temperature; Lignin; Kraftpulping; Selectivity; viscosity; Kappa number; chemical degradation; Disproportionation; TECHNOLOGY Chemical engineering Chemical process and manufacturing engineering Cellulose and paper engineering; TEKNIKVETENSKAP Kemiteknik Kemisk process- och produktionsteknik Cellulosa- och pappersteknik;

    Sammanfattning : The amount of lignin which needs to be removed according to the slow residual delignification phase in kraft pulping, i e residual phase lignin, has been studied as a function of the process conditions. The variebles studied were the concentrations of hydroxide ions, hydrogensulfide ions, sodium ions (ionic strength) and temperature. LÄS MER

  2. 2. On the Interrelation Between Kraft Cooking Conditions and Pulp Composition

    Detta är en avhandling från Stockholm : KTH

    Författare :Catrin Gustavsson; KTH.; [2006]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Delignification; Kraft pulping; Residual phase lignin; Hydroxide; Hydrogen sulphide ion; Ionic strength; Temperature; Bleachability; Hexenuronic acid; Carbohydrates; TECHNOLOGY Chemical engineering Chemical process and manufacturing engineering Cellulose and paper engineering; TEKNIKVETENSKAP Kemiteknik Kemisk process- och produktionsteknik Cellulosa- och pappersteknik;

    Sammanfattning : In the early 1990’s, a lot of work was focused on extending the kraft cook to a low lignin content (low kappa number). The driving force was the need to further reduce the environmental impact of the bleaching, as less delignification work would be needed there. LÄS MER

  3. 3. Some aspects on the effects of dissolved wood components in kraft pulping

    Detta är en avhandling från Stockholm : KTH

    Författare :Ragnar Sjödahl; KTH.; [2006]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Delignification; Dissolved wood components; Black liquor; Defibration point; TECHNOLOGY Chemical engineering Chemical process and manufacturing engineering Cellulose and paper engineering; TEKNIKVETENSKAP Kemiteknik Kemisk process- och produktionsteknik Cellulosa- och pappersteknik;

    Sammanfattning : During kraft cooking a significant part of the wood material, especially lignin and hemicelluloses, is degraded and dissolved in the cooking liquor, rendering a broad range of degradation products with different molecular mass and functional groups. The main part of this thesis has been devoted to clarify the role of these dissolved wood components (DWC) during kraft cooking. LÄS MER