Sökning: "Dissolved lignin"

Visar resultat 1 - 5 av 40 avhandlingar innehållade orden Dissolved lignin.

  1. 1. The Impact of Dissolved Matter on Fiberline Processes

    Författare :Caroline Wilke; Ulf Germgård; Niclas Andersson; Juha Fiskari; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bleach plant control; Carbonate; Carryover; Chlorine dioxide bleaching; COD; Dissolved lignin; Dissolved matter; Fiberline control; Filtrate; Hexenuronic acid; Hydrogen peroxide bleaching; Kappa number; Oxygen delignification; Wash loss; Chemical Engineering; Kemiteknik;

    Sammanfattning : The impact of dissolved matter on the performance of four fiberline process stages was investigated: oxygen delignification, hot acid treatment, chlorine dioxide bleaching, and hydrogen peroxide reinforced alkaline extraction. In particular the impact on delignification due to dissolved lignin was studied. LÄS MER

  3. 2. Towards a pure kraft lignin

    Författare :Rufus Ziesig; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LignoBoost; black liquor; lignin; impurities; purification; carbohydrate; inorganics; precipitation;

    Sammanfattning : The most widely used production method for paper pulp in the world is kraft pulping. In chemical pulping the polymer, lignin, which binds the wood fibres together, is partly depolymerized. This allows the wood fibres to be separated from each other. LÄS MER

  4. 3. Fate and transport of POPs in the aquatic environment : with focus on contaminated sediments

    Författare :Sarah Josefsson; Karin Wiberg; Mats Tysklind; Kjell Leonardsson; Jonas S Gunnarsson; Jussi Kukkonen; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bioturbation; bioirrigation; bioaccumulation; secondary sources; buried contaminants; sediment remediation; active capping; thin-layer capping; Marenzelleria spp.; Baltic Sea; polychlorinated dibenzo-p-dioxins; polychlorinated dibenzofurans; polychlorinated biphenyls; hexachlorobenzene; octachloro¬styrene; polybrominated diphenyl ethers; PCDD Fs; PCBs; HCB; OCS; PBDEs; water sampling; passive sampling; particulate fraction; freely dissolved; apparently dissolved; colloid; organic carbon; activated carbon; lignin; sediment-to-water flux; spring bloom; Environmental chemistry; Miljökemi; Persistent organic compounds; Persistenta organiska föreningar; Environmental Science; miljövetenskap;

    Sammanfattning : Persistent organic pollutants (POPs) are hydrophobic substances that readily sorb to organic matter in particles and colloids instead of being freely dissolved in the water phase. This sorption affects the bio­availability and environmental transport of the POPs. LÄS MER

  5. 4. The initial phase of sodium sulfite pulping of softwood : A comparison of different pulping options

    Författare :Raghu Deshpande; Ulf Germgård; Pedro Fardim; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Activation energy; acid sulfite pulping; bisulfite pulping; cellulose; delignification; dissolving pulp; extractives; glucomannan; hemicelluloses; lignin; lignin condensation; lignin carbohydrate complexes; pine; spruce; thiosulfate; total SO2; xylan; Chemical Engineering; Kemiteknik;

    Sammanfattning : Single stage and two-stage sodium sulfite cooking were carried out on either spruce, pine or pure pine heartwood chips to investigate the influence of several process parameters on the initial phase of such a cook down to about 60 % pulp yield. The cooking experiments were carried out in the laboratory with either a lab-prepared or a mill-prepared cooking acid and the temperature and time were varied. LÄS MER

  7. 5. Lignin Exraction from Black Liquor: Precipitation, filtration and washing

    Författare :Henrik Wallmo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Lignin; Filtration; Separation; Black liquor; Precipitation; Washing.; Absorption;

    Sammanfattning : Lignin extraction is a very interesting option for pulp mills today. Lignin is one major component, present as a dissolved organic compound, in black liquor, which is a by-product in the alkaline pulping of wood. After the digestion of wood chips, the black liquor is separated from the cellulose. LÄS MER