Sökning: "kraft cook"
Visar resultat 1 - 5 av 17 avhandlingar innehållade orden kraft cook.
1. Xylan Reactions in Kraft Cooking : Process and Product Considerations
Sammanfattning : Xylan is the main hemicellulose in birch, eucalyptus, and most other hardwood species. During kraft pulping a series of chemical reactions and physical processes involving xylan takes place. LÄS MER
2. Aspects of extended impregnation kraft cooking for high-yield pulping of hardwood
Sammanfattning : The long-term trend regarding wood is an increase in price. Because wood contributes to a large part of production costs, the efficient utilisation of wood is greatly desired to reduce production costs for kraft pulp producers. During the 1990s, the development of improved modified kraft cooking began, which led to higher yields. LÄS MER
3. Interfacing spectrophotometry to process liquors applications to kraft pulping
Sammanfattning : This thesis summarizes the outcome of work performed withthe objective to contribute to the knowledge and development ofthe kraft cooking process using spectrophotometricinterfaces.In kraft cooking, it is desirable to maximize the removal oflignin in the cook without loss of pulp strength. LÄS MER
4. On the Interrelation Between Kraft Cooking Conditions and Pulp Composition
Sammanfattning : In the early 1990’s, a lot of work was focused on extending the kraft cook to a low lignin content (low kappa number). The driving force was the need to further reduce the environmental impact of the bleaching, as less delignification work would be needed there. LÄS MER
5. Improved Usage of Wood Raw Material through Modification of the Kraft Process
Sammanfattning : The kraft process is a complex system with many variables, and though the process is fairly well understood, there is still much we do not know. This thesis examines some aspects of the kraft process that could prove to be of interest for the pulp and paper industry, specifically, the impact of wood chip impregnation and of the chemical structure of xylan on spruce kraft pulp. LÄS MER