Sökning: "pulp 2011"

Visar resultat 1 - 5 av 27 avhandlingar innehållade orden pulp 2011.

1. 1. 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

3. 2. ANALYZING THE HYDRO DYNAMICS AND THE CHEMICAL REACTIONS IN PULP DIGESTER SYSTEMS USING CFD MODELLING

   Författare :Bijan Pourian; Erik Dahlquist; Laszlo Fuchs; Mälardalens högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; MODELLING; SIMULATION; PULP; DIGESTER. CHEMICAL; MULTIPHASE; Cellulose and paper engineering; Cellulosa- och pappersteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

   Sammanfattning : The aim of this thesis is to use differential analysis and finite volume method (FVM) to model and analyze a continuous pulp digester in order to create a detailed picture of the flow behaviour and chemical reactions in the digester. This information will be used to optimize wood chip flow and reactions and to diagnose and avoid faults such as hang-ups and channelling. LÄS MER

4. 3. Molecular Interactions in Thin Films of Biopolymers, Colloids and Synthetic Polyelectrolytes

   Författare :Johansson Erik; Lars Wågberg; Andreas Fery; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polyelectrolyte multilayers; Layer-by-Layer assembly; Adhesion; Adsorption; Young s modulus; Mechanical buckling; AFM; JKR; SPAR; QCM-D; SIEBIMM; PAH; PAA; Starch; NFC; Nanocellulose;

   Sammanfattning : The development of the layer-by-layer (LbL) technique has turned out to be an efficient way to physically modify the surface properties of different materials, for example to improve the adhesive interactions between fibers in paper. The main objective of the work described in this thesis was to obtain fundamental data concerning the adhesive properties of wood biopolymers and LbL films, including the mechanical properties of the thin films, in order to shed light on the molecular mechanisms responsible for the adhesion between these materials. LÄS MER

5. 4. Analysing different technology pathways for the pulp and paper industry in a European energy systems perspective

   Författare :Johanna Jönsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; technology pathways; pulp and paper industry; energy market scenarios; biorefinery; kraft pulp mill; global CO2 emission;

   Sammanfattning : For the pulp and paper industry (PPI), earlier research has shown that there are many technology pathways, proven and new, available for improvement of energy efficiency and additional sales of (new) products. Some pathways can only be implemented in kraft mills, e.g. black liquor gasification (BLG), but some can be implemented industry-wide, e. LÄS MER

7. 5. Low consistency refining of mechanical pulp : process conditions and energy efficiency

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

   Sammanfattning : 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. LÄS MER