Displacement washing of kraft pulp cooked from a blend of hardwoods
-
František Potůček
and
Jozef Miklík
Abstract
The aim of this work was to investigate the displacement washing of kraft pulp manufactured from a blend of hardwoods. The experiments were carried out in a laboratory washing cell. In order to characterise the pulp fibres, the degree of freeness, kappa number, fibre length, as well as the specific volume and specific surface of swollen fibres were determined. The displacement washing process was described by displacement washing curves recorded for alkali lignin as a tracer. Mathematical treatment of the washing curves, obtained as a response to the step input signal, gave the Péclet number characterising the displacement of alkali lignin from the pulp pad. For detailed description of the displacement washing process, further parameters, such as the traditional wash yield, axial dispersion coefficient as well as the mean residence time and the space time were also evaluated. The results obtained for hardwood pulp were compared with those for softwood pulp published earlier. With respect to different chemical composition and morphological characteristics affecting both concentration of alkali lignin in mother liquor and physical properties of pulp pad, the displacement washing efficiency of hardwood pulp was found to be unambiguously greater in comparison with softwood pulp.
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© 2009 Institute of Chemistry, Slovak Academy of Sciences
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Articles in the same Issue
- Co-digestion of agricultural and industrial wastes
- Comparison of anoxic granulation in USB reactors with various inocula
- A study of selected phytoestrogens retention by reverse osmosis and nanofiltration membranes - the role of fouling and scaling
- Displacement washing of kraft pulp cooked from a blend of hardwoods
- Solid suspension and gas dispersion in gas-solid-liquid agitated systems
- Implementation of marginal quantities in management of cogeneration units operating in liberal market environment
- Kinetic study of wood chips decomposition by TGA
- LES and URANS modelling of turbulent liquid-liquid flow in a static mixer: Turbulent kinetic energy and turbulence dissipation rate
- Steady state and dynamic simulation of a hybrid reactive separation process
- Prediction of liquid-liquid flow in an SMX static mixer using large eddy simulations
- Simulation of a hybrid fermentation-separation process for production of butyric acid
- Simulation of aerobic landfill in laboratory scale lysimeters — effect of aeration rate
- Application of anoxic fixed film and aerobic CSTR bioreactor in treatment of nanofiltration concentrate of real textile wastewater
- Pretreatment of landfill leachate by chemical oxidation processes
- Development of β and α isotactic polypropylene polymorphs in injection molded structural foams
- Effect of time on the metal-support (Fe-MgO) interaction in CVD synthesis of single-walled carbon nanotubes
- Unique role of water content in enzymatic synthesis of ethyl lactate using ionic liquid as solvent
- Autothermal biodrying of municipal solid waste with high moisture content
- Kinetics of nitric oxide oxidation
