Search for dissertations about: "alkalinity"

Showing result 11 - 15 of 52 swedish dissertations containing the word alkalinity.

  2. 11. Sustainable Water Quality Monitoring for Developing Countries in the Context of Mining : Monitoring systems and modelling

    Author : Clemencio Nhantumbo; Avdelningen för Teknisk vattenresurslära; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Water Quality; Monitoring systems; Modelling; pH and alkalinity;

    Abstract : Mining, seen as a source of revenue in most developing countries, threatens seriously the environment. Mining impacts the water quality and one of the main problems of mining is acid mine drainage. Low pH and high concentration of heavy metals characterize acid mine drainage. READ MORE

  4. 12. Oxygen-Alkali Treatment of Kraft Pulp and Cellobiitol. Model Experiments and Applied Studies of Interest for Oxygen Bleaching

    Author : Bengt Järrehult; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; selectivity; pH-levels; copper; oxygen delignification; catalytic effects; iron; alkali; cellobiitol; magnesium; yield;

    Abstract : During oxygen delignification of kraft pulp the alkalinity has a decisive influence upon the selectivity, defined as viscosity at a given kappa number. Using 0.2% pulp consistency in order to achieve constant pH-levels a minimum selectivity was reached at pH 13, corresponding to 0.1 M NaOH. READ MORE

  5. 13. Determination of protolytes by flow procedures : applications to liquors from the hydrometallurgical nickel industry

    Author : Isel Gertrudis Cortés Nodarse; KTH; []
    Keywords : ;

    Abstract : The general intention of this work is to contribute inreplacing complicated and time consuming titration methods foracid/base determination in cases where a rapid answer is morevaluable than a very high accuracy. The versatility of FlowInjection Analysis (FIA) is utilised for the determination ofprotolyte compounds, considering their role in our daily lifeas well as in science and technology. READ MORE

  6. 14. Mass Transport in Wood Disintegration: Implications for the Pulp and Paper Industry

    Author : Roujin Ghaffari; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mass transport; specific ion effects; impregnation; Kraft pulping; ionoSolv; ionic liquids; delignification;

    Abstract : Efficient delignification and fractionation processes are essential in the pulp and paper industry. Mass transport events in wood fractionation are of great importance, specifically in two main stages, namely, the mass transport of chemicals into wood and the mass transport of degraded lignin molecules out of cellulose confinements. READ MORE

  7. 15. Mass transfer challenges in wood decomposition

    Author : Roujin Ghaffari; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; diffusion cells; kraft process; lignin; lignin transport;

    Abstract : Even though the kraft cooking operation is more than 100 years old, the rate-determining step of this operation has not been fully elucidated. Recent studies point in the direction of mass transport of liberated lignin fragments from the fibers' walls into black liquor being influential in rate determination of kraft cooking. READ MORE