Sökning: "Defibration"

Visar resultat 1 - 5 av 11 avhandlingar innehållade ordet Defibration.

  1. 1. A numerical and experimental study of initial defibration of wood

    Författare :Stefan Holmberg; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite element simulations; fracture; deformation; fibre; defibration; wood; Building construction; Byggnadsteknik;

    Sammanfattning : A major drawback of the defibration or refining process in manufacturing pulp is that of its large energy requirements. If the mechanics of the process were better understood, large amounts of energy could probably be saved. The initial defibration seems to be crucial for both the quality of the pulp and the total consumption of energy. LÄS MER

  3. 2. Manufacture of straw MDF and fibreboards

    Författare :Sören Halvarsson; Håkan Edlund; Magnus Norgren; Thomas Amidon; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rice; Wheat; Straw; MDF; HDF; UF; MUF; MDI; Non-resin; binderless MDF; Ash; Silicon; SEM; Hot-pressing; MOR; MOE; IB; Thickness swelling; MDF properties; fibre swelling; WRV; Refining; Defibration.; NATURAL SCIENCES; NATURVETENSKAP; Chemical engineering; Kemiteknik; Chemical process and manufacturing engineering; Kemisk process- och produktionsteknik;

    Sammanfattning : The purpose of this thesis was to develop an economical, sustainable, and environmentally friendly straw Medium Density Fibreboard (MDF) process, capable of full-scale manufacturing and to produce MDF of requested quality. The investigated straw was based on wheat (Triticum aestivum L.) and rice (Oryzae sativa L.). LÄS MER

  4. 3. Wood and fibre mechanics related to the thermomechanical pulping process

    Författare :Jan-Erik Berg; Per Engstrand; Per A. Gradin; Tomas Björkqvist; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic emission; Chips; Compression tests; Defibration; Disc refiners; Energy consumption; Fibre structure; Force sensors; Fracture; Impact strength; Mathematical analysis; Moisture content; Picea abies; Refining; Stiffness degradation; Strains; Temperature; Thermomechanical pulping; Velocity; Chemical engineering; Kemiteknik;

    Sammanfattning : The main objective of this thesis was to improve the understanding of some aspects on wood and fibre mechanics related to conditions in the thermomechanical pulping process. Another objective was to measure the power distribution between the rotating plates in a refiner. LÄS MER

  5. 4. Deformation and Fracture of Wood in Initial Defibration Processes

    Författare :Stefan Holmberg; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : .... LÄS MER

  7. 5. Modification of fluff pulp fibres: Cross-linking and alkali extraction

    Författare :Kristoffer Lund; Chalmers tekniska högskola; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; fibre network; dry defibration; network strength; fluff pulp; Absorption; cross-linking; alkali extraction; kraft pulp;

    Sammanfattning : Fluff pulp has been one of the key components of hygienic products, such as diapers, for many years. Fluff pulp is dry defibrated and air-laid into the absorption core of diapers. The introduction of superabsorbent polymers (SAPs) in the 1980s decreased the dependence on fluff pulp, as the SAPs became the main absorbing material. LÄS MER