Search for dissertations about: "Disc refiners"

Found 5 swedish dissertations containing the words Disc refiners.

  2. 1. Wood and fibre mechanics related to the thermomechanical pulping process

    Author : Jan-Erik Berg; Per Engstrand; Per A. Gradin; Tomas Björkqvist; Mittuniversitetet; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 2. Improved energy efficiency in double disc chip refining

    Author : Dino Muhic; Per Engstrand; Lars Sundström; Mats Ullmar; Christer Sandberg; Hans Höglund; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermomechanical pulping TMP ; double disc refining; high intensity; Chemical engineering; Kemiteknik;

    Abstract : The electrical energy consumption in thermomechanical pulping (TMP) is very high, in the range of 2 – 3 MWh/adt depending on process solution and on the product quality specifications for the paper product. Both pulpwood and energy prices have increased rapidly for some time. READ MORE

  5. 3. Measurement of shear force, temperature profiles and fibre development in mill-scale TMP refiners

    Author : Hans-Olof Backlund; FSCN - Fibre Science and Communication Network; []
    Keywords : Shear force; Tangential force; Temperature profile; Thermomechanical pulping;

    Abstract : Two different force sensors have been developed for tangential forcemeasurements in commercial TMP refiners, one is based on the use of piezoelectricsensors and the other on strain gauges. The measurements are used to learn moreabout the refining mechanism in both single-disc (SD) refiners and conical disc(CD) refiners. READ MORE

  6. 4. Low consistency refining of mechanical pulp : process conditions and energy efficiency

    Author : Stefan Andersson; Per Engstrand; Christer Sandberg; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical pulping; low consistency refining; energy efficiency; rotor position; plate gap; fibre concentration;

    Abstract : The thesis is focussed on low consistency (LC) refining of mechanical pulp. Theresearch included evaluations of energy efficiency, development of pulpproperties, the influence of fibre concentration on LC refining and effects of rotorposition in a two-zoned LC refiner. READ MORE

  7. 5. Distributions Of Fiber Characteristics As A Tool To Evaluate Mechanical Pulps

    Author : Sofia Reyier Österling; Per Engstrand; Hans Höglund; Olof Ferritsius; Rita Ferritsius; Hans Ersson; Per Gradin; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber; fibre; fiber characteristics; fiber dimension; fiber properties; mechanical pulp; FiberLab; raw data; distribution; fiber wall thickness; BIN; bonding ability influence; bonding indicator; bonding ability; fiber width; fibrillation; collapse resistance; laboratory sheet; fiber analyzer; optical analyzer; TMP; CTMP; SGW; sheet model; prediction; fiber characterization; hydrocyclone; fractionation; kernel density estimation; KDE; diffusion mixing; acoustic emission; F0.90; Norway spruce; Picea abies;

    Abstract : Mechanical pulps are used in paper products such as magazine or news grade printing papers or paperboard. Mechanical pulping gives a high yield; nearly everything in the tree except the bark is used in the paper. This means that mechanical pulping consumes much less wood than chemical pulping, especially to produce a unit area of printing surface. READ MORE