Sökning: "Extractives"

Visar resultat 1 - 5 av 23 uppsatser innehållade ordet Extractives.

  1. 1. Analysis and Valorization of Bark from Silver Birch, Scots Pine, and Norway Spruce : Compositional analysis of bark from common Swedish trees in forestry, to optimize sustainability procedures and monetary value of bark residue

    Kandidat-uppsats, Umeå universitet/Kemiska institutionen

    Författare :Isak Lindbäck; [2022]
    Nyckelord :;

    Sammanfattning : Silver birch, Scots pine, and Norway spruce are the three most common types of trees in Sweden and make up to 90% of standing volume in Swedish forests (Skogsstyrelsen 2015, 3). With millions of cubic meters of wood being cut down annually, bark and other residues that cannot be used for sawn timber is left over and burnt for energy. LÄS MER

  3. 2. Reactivity increasement of prehydrolysis kraft pulp from Acacia crassicarpa and Eucalyptus hybrids

    Master-uppsats, KTH/Träkemi och massateknologi

    Författare :Edward Tandy; [2022]
    Nyckelord :Acacia crassicarpa; Eucalyptus hybrids; Pentosan removal; Pulp yield; Prehydrolysis kraft pulp; Reactivity; Acacia crassicarpa; Eucalyptushybrider; Förhydrolyserad kraftmassa; Massautbyte; Pentosan; Reaktivitet;

    Sammanfattning : Syftet med detta examensarbete var att öka reaktiviteten hos förhydrolyserad kraftmassa genom att använda tidigare förhydrolysat och svavelsyra under förhydrolysen. Först bestämdes den kemiska sammansättningen av två olika vedråvaror (Acacia crassicarpa och Eucalyptushybrider) för att observera och korrelera med förhydrolysprocessen. LÄS MER

  4. 3. Design av testanläggning för förbränning av pellets i matlagningsspisar : Analys av hur pelletsens egenskaper påverkar emissioner och effektivitet under förbränning

    Master-uppsats, Karlstads universitet/Institutionen för ingenjörs- och kemivetenskaper (from 2013)

    Författare :Nellie Dalqvist; [2022]
    Nyckelord :Pellets; askhalt; extraktivämnen;

    Sammanfattning : Renewable energy sources have dominated energy use throughout human history and biomass is one of the world's oldest energy sources. The use of biomass as a fuel has increased in recent decades and has led to great technological development as a result of the growing demands for sustainable solutions. LÄS MER

  5. 4. Spruce bark biorefinery

    Kandidat-uppsats, KTH/Fiber- och polymerteknologi

    Författare :Leon Ahlström; Rebecca Mattsson; Hampus Eurén; Alicia Lidén; [2021]
    Nyckelord :Norway spruce bark; bark biorefinery; extractives; cellulose; lignin; non-cellulose; polysaccharides; soxhlet extraction; hot-water extraction; organosolv extraction; PAA; delignification; carbohydrate analysis; 2D HSQC-NMR and FTIR; Granbark; bark bioraffinaderi; lignin; organosolv extraktion; hot-water extraktion;

    Sammanfattning : Spruce Bark contains several fundamental main substances; lignin, non-cellulose polysaccharides, cellulose and extractives. This undergraduate study focuses on developing a process to extract each of these components from spruce bark using a biorefinery concept, with a main focus on extracting lignin without degradation. LÄS MER

  7. 5. The Influence of pH, Temperature and Number of Wash Steps on the Washing Efficiency of CTMP Pulp

    Master-uppsats, Karlstads universitet/Avdelningen för kemiteknik

    Författare :André Monlars; [2021]
    Nyckelord :Mechanical pulp; Chemi-thermomechanical pulp; Picea abies; Extractives; Wood resin; Deresination; Washing; Mekanisk massa; Kemitermomekanisk massa; Picea abies; Extraktivämnen; Tvättning;

    Sammanfattning : In this report, the washing efficiency of chemi-thermomechanical pulp (CTMP) from Norway spruce (Picea abies) was investigated when adjusting the temperature and pH during washing as well as implementing different number of wash steps. Concurrent effects of having a high pH and temperature were also examined. LÄS MER