Sökning: "vacuum dewatering"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden vacuum dewatering.

  1. 1. Vacuum Dewatering of Cellulosic Materials : New insights into transport phenomena in the papermaking process

    Författare :Björn Sjöstrand; Lars Nilsson; Christphe Barbier; Henrik Ullsten; Martin Hubbe; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vacuum dewatering; numerical model; water removal; air penetration; papermaking; microfibrillated cellulose; dialcohol cellulose; strength additives; retention aids; drainage; water retention value; Chemical Engineering; Kemiteknik;

    Sammanfattning : Working towards sustainable development within the forest industry, the dewatering of pulp and paper must be fully understood along with the dewatering of other cellulose-based materials. Huge amounts of energy are used during paper manufacturing so there is a potential for making the processes more energy-efficient. LÄS MER

  3. 2. Dewatering aspects at the forming section of the paper machine : Rewetting and forming fabric structure

    Författare :Björn Sjöstrand; Lars Nilsson; Christophe Barbier; David McDonald; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rewetting; forming fabric; forming section; dewatering; web dryness; high vacuum suction box; vacuum dewatering; forming fabric design; numerical model; Chemical Engineering; Kemiteknik;

    Sammanfattning : The underlying motives of the research undertaken here are twofold: to obtain a deeper understanding of the dewatering mechanisms at the forming section of a papermaking machine and to develop numerical models that describe the flow through forming fabrics. More comprehensive knowledge of dewatering in the forming section allows suggestions to be made for improvements that reduce the amount of energy used in the process without affecting the quality of the end product. LÄS MER

  4. 3. On Suction Box Dewatering Mechanisms

    Författare :Peter Åslund; Bo Norman; Timoty Patterson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Suction box; vacuum; water removal; compressibility; displacement; rewetting; laboratory equipment; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : In previous studies on suction box dewatering, three mechanisms were identified that determine the dry content of a web, viz. web compression, displacement of water by air and rewetting. LÄS MER

  5. 4. Studies of Vacuum Dewatering on Low Grammage Paper Webs

    Författare :Rickard Granevald; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Sammanfattning : A laboratory scale apparatus to simulate high-vacuum dewatering of low grammage paper sheets, typically for tissue products has been constructed. Vacuum level, vacuum pulse dwell time and frequency of single vacuum pulses are in the range typical for a Through Air Drying (TAD) tissue machine. The vacuum pulse dwell time was varied from 0. LÄS MER

  7. 5. Vacuum dewatering of low-grammage paper webs and fabrics

    Författare :Rickard Granevald; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Sammanfattning : .... LÄS MER