Sökning: "Avdelningen för kemiteknik"

Visar resultat 1 - 5 av 193 avhandlingar innehållade orden Avdelningen för kemiteknik.

  1. 1. Extended Mercerization Prior to Carboxymethyl Cellulose Preparation

    Författare :Heléne Almlöf; Ulf Germgård; Björn Kreutz; Monica Ek; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carboxymethyl cellulose; Mercerization; DS; FT Raman spectroscopy; Filtration ability; Chemical engineering; Kemiteknik; Chemical Engineering; Kemiteknik;

    Sammanfattning : Carboxymethyl cellulose (CMC) is produced commercially in a two-stage process consisting of a mercerization stage, where the pulp is treated with alkali in a water alcohol solution, followed by an etherification stage in which monochloroacetic acid is added to the pulp slurry. In this thesis an extended mercerization stage of a spruce ether pulp was investigated where the parameters studied were the ratio of cellulose I and II, concentration of alkali, temperature and retention time. LÄS MER

  3. 2. Optics of coated paperboard : Aspects of surface treatment on porous structures

    Författare :Erik Bohlin; Caisa Johansson; Magnus Lestelius; Per Edström; Per-Åke Johansson; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Sammanfattning : Calendering of coated and uncoated paper is widely used to enhance optical properties such as gloss and print quality. The aim of this thesis is to characterize coatings and prints, and to validate models using experimental results from optical measurements of physical samples. Calendering of coated paper often leads to a brightness decrease. LÄS MER

  4. 3. Improvement of the tissue manufacturing process

    Författare :Jonna Boudreau; Bengt Järrehult; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Sammanfattning : The creping process and the conditions on the Yankee cylinder are the key factors in the production process. They need to be kept under good control in order to maintain a high and uniform quality. LÄS MER

  5. 4. Ethanol Pulping of Reed Canary Grass

    Författare :Helena Håkansson; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pulping; Nonwood plants; Reed canary grass; Ethanol; Organosolv pulping; Statistical analysis; Chemical Engineering; Kemiteknik;

    Sammanfattning : The aim of this study was to investigate the possibility of processing an agricultural crop grown in Sweden to usable pulp. A further purpose was to study ethanol pulping applied to a non-wood raw material.The first part of this thesis deals with the criteria for selecting a fibre crop for further studies. LÄS MER

  7. 5. Preparation and Characterization of Chemical Pulps from Wood and Reed Canary Grass

    Författare :Helena Håkansson; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pulping; wood; reed canary grass; acid hydrolysis; microcrystalline cellulose; Chemical Engineering; Kemiteknik;

    Sammanfattning : This thesis presents laboratory results from ethanol pulping of reed canary grass for the production of paper pulp. The focus was on the influence of cooking pa-rameters on the delignification. The strength of the grass pulps was found to be low and the use of such pulps will therefore be limited to a few products. LÄS MER