Search for dissertations about: "sulfite pulping"

Showing result 1 - 5 of 11 swedish dissertations containing the words sulfite pulping.

  2. 1. The initial phase of sodium sulfite pulping of softwood : A comparison of different pulping options

    Author : Raghu Deshpande; Ulf Germgård; Pedro Fardim; Karlstads universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Activation energy; acid sulfite pulping; bisulfite pulping; cellulose; delignification; dissolving pulp; extractives; glucomannan; hemicelluloses; lignin; lignin condensation; lignin carbohydrate complexes; pine; spruce; thiosulfate; total SO2; xylan; Chemical Engineering; Kemiteknik;

    Abstract : Single stage and two-stage sodium sulfite cooking were carried out on either spruce, pine or pure pine heartwood chips to investigate the influence of several process parameters on the initial phase of such a cook down to about 60 % pulp yield. The cooking experiments were carried out in the laboratory with either a lab-prepared or a mill-prepared cooking acid and the temperature and time were varied. READ MORE

  4. 2. Wood chips for kraft and sulfite pulping : evaluation of novel forest-industrial drum-chipping technology

    Author : Jessica Gard Timmerfors; Leif J. Jönsson; David Blomberg; Sören Östlund; Umeå universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wood chip; drum chipper; impregnation; pulping; sulfite process; kraft process; Scots pine; Norway spruce; heartwood; frozen wood; moisture content;

    Abstract : Wood chipping and the supply of high-quality wood chips are of critical importance for most forest-industrial processes. The quality of wood chips affects product yield, product quality, and processability. READ MORE

  5. 3. High-yield chemimechanical pulping of bagasse

    Author : Fuhua Peng; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pretreatment; newsprint; paper properties; bleaching; chemimechanical pulping; hydrogen peroxide; specific energy; sodium sulfite; sodium hydroxide; impregnation; bagasse;

    Abstract : .... READ MORE

  6. 4. The initial phase of the sodium bisulfite pulping of softwood dissolving pulp

    Author : Raghu Deshpande; Ulf Germgård; Martin Ragnar; Karlstads universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Activation energy; bisulfite pulping; cellulose; delignification; extractives; glucomannan; hemicelluloses; lignin; pine; spruce; thiosulfate; total SO2; xylan; Chemical Engineering; Kemiteknik;

    Abstract : The sulfite pulping process is today practised in only a small number of pulp mills around the globe and the number of sulfite mills that use sodium as the base (cation) is less than five. However, due to the increasing interest in the wood based biorefinery concept, the benefits of sulfite pulping and especially the sodium based variety, has recently gained a lot of interest. READ MORE

  7. 5. Galactoglucomannan recovery from softwood spent sulfite liquor: Challenges, process design and techno-economic evaluations

    Author : Basel Al-Rudainy; Avdelningen för kemiteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Galactoglucomannan; Lignin; Lignosulfonates; Lignin-carbohydrate-complexes; Membrane filtration; Dead-end filtration; Precipitation; Adsorption;

    Abstract : In the production of pulp and paper, water-soluble components, such as hemicellulose, monosaccharides, and lignin, are released and accumulate in the process water. The process water is usually concentrated and incinerated for heat generation and the recovery of pulping chemicals, such as in the Kraft and sulfite processes. READ MORE