Search for dissertations about: "Chemical pulping"

Showing result 1 - 5 of 118 swedish dissertations containing the words Chemical pulping.

2. 1. 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

4. 2. Ethanol Pulping of Reed Canary Grass

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

   Abstract : 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. READ MORE

5. 3. 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

6. 4. Ethanol pulping of reed canary grass

   Author : Helena Håkansson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pulping; ethanol; nonwood plants; reed canary grass; organosolv pulping; statistical analysis;

   Abstract : .... READ MORE

7. 5. Kraft lignin valorization by hydrotreatment over Mo-based sulfided catalysts

   Author : Muhammad Abdus Salam; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Char; Bio-oil; Kraft Lignin; Hydrodeoxygenation; Y-zeolite; Metal sulfide; Depolymerization; Acidity;

   Abstract : The production of green fuels and chemicals from bio-based feedstock can suppress the dependency on fossil resources and help mitigate global climate challenges. Kraft lignin is a thermochemically modified natural lignin obtained from the pulping process as a byproduct. READ MORE