Sökning: "precipitation black liquor"
Visar resultat 11 - 15 av 19 avhandlingar innehållade orden precipitation black liquor.
11. Extraction of Lignin from Kraft Cooking Liquor by Ultrafiltration
Sammanfattning : Lignin is a potential biofuel which can be extracted from kraft cooking liquor. Lignin can also prove valuable as a speciality chemical. By extracting lignin potential economical revenue can be gained by pulp mills, as well as technical benefits such as easier delignification and bleaching. LÄS MER
12. Thermodynamic modelling of black liquor-related solutions. Pitzer method for estimating activities, solubilities and boiling point rise
Sammanfattning : Black liquor is considered as being one of the most important process streams as far as the design and optimization of kraft pulp mills are concerned. Many methods have been developed in order to describe and, possibly, predict its physico-chemical properties. Most of them are, however, empirical methods that are difficult to generalize. LÄS MER
13. Precipitation of Kraft Lignin from Aqueous Solutions
Sammanfattning : One way of improving the materials yield of a kraft paper pulp process, and simultaneously providing the industry with aromatic macromolecular structures, is to extract lignin from the black liquor. This can be done by lowering the pH of the black liquor, which will result in the precipitation of the lignin. LÄS MER
14. Xylan sorption kinetics at industrial conditions
Sammanfattning : The kraft process is the most utilised method for the production of wood based chemical pulp for paper applications. During a kraft cook about half of the wood material is dissoluted into the cooking liquor making the liberation of individual fibres possible. This low yield is a great disadvantage for process economy. LÄS MER
15. The Use of Lignin Derivatives to Improve Selected Paper Properties
Sammanfattning : Ved består huvudsakligen av tre typer av polymerer, cellulosa, hemicellulosa och lignin. Lignin bildas i naturen genom enzymatiskt initierad oxidativ koppling av tre olika typer av fenylpropan-enheter. Dessa bygger genom olika kol-kol- och kol-syre-bindningar upp en amorf tredimensionell polymer. LÄS MER