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Corrigendum to “utilisation of controlled pore topology for the separation of b...

Equation for fitting dispersed systems gravity and centrifuge settling data

Liquid phase accumulation kinetics during sedimentation and centrifugation serves as a source of information about the average settling properties of dispersed systems. A power order fitting function is proposed for describing the dependence of accumulated liquid phase volume on settling time. The function validity was tested for numerous experimental settling data under gravitational and centrifugal forces for...

Application of binary packing for starch separation by hydrodynamic chromatography

Columns packed with commercial glass beads of 5 and 19 microns average diameter and binary mixtures with finest fraction of 5 micron (30 % volume fraction of the mixture) were used to analyse starch by hydrodynamic chromatography (HDC). Experiments were carried out at 3 and 15 ºC. The observed resolution increased with the application of binary packing as compared with single-size packing. The best results were...

Permeability analysis in bisized porous media : wall effect between particles o...

The permeability of binary packings of glass beads with different size ratio – 13.3, 20, and 26.7, was investigated. In the Kozeny–Carman equation, the dependence of the tortuosity τ on the mixture porosity ε(xD) was described according to τ = 1/εn for different volume fraction of large particles in the mixture, xD. Obtained data on packing permeability shows that the parameter n is a function of the volume fra...

Simulation of liquid phase accumulation for the centrifugal dewatering of activ...

Centrifugation of activated sludge is a frequently used dewatering process but, in spite of this, there is a need for a fitting function for moderate and high sludge concentrations. Liquid phase accumulation kinetics during centrifugation may be used as a source of information about the sedimentahon properties and the governing mechanism during cake formation. For this purpose, activated sludge at different con...

Starch analysis using hydrodynamic chromatography with a mixed-bed particle column

Columns packed with commercial glass beads 5 and 19 lm average size and a mixture of both (0.7 volume fraction of large particles) were used to analyse starch composition by hydrodynamic chromatography (HDC), applying water as mobile phase. To obviate retrogradation, experiments were carried out at column temperatures of 15 and 3 °C and several types of starch were assayed. In what concerns amylopectin and amyl...

Extending Kozeny-Carman permeability model to highly porous media

Anomalous normalised permeability as a ratio of permeability to square of particle size for snow, diatomite, kieselgel was considered using Kozeny-Carman model and tortuosity factor defined as the square of average tortuosity pathway. Since the Kozeny-Carman model is based on the geometrical models of a capillary tube, the model adopted for high porous media with shaped particles (often with fractal properties)...

Hindered motion in highly porous media : steric and fractal approaches

Two-dimensional simulation of porous media using a pore fractal dimension D was performed. Obtained results can be outlined as follows: 1). Starting from large pores with aspect ratio of micro-particle size to pore size λ > 0.001, molecules (or test object) recognise the pore volume as a partially restricted space with reduced fractal dimension. 2). The restriction effect on a molecule depends on pore topology ...

Starch analysis using hydrodynamic chromatography with a mixed-bed particle column

Columns packed with commercial glass beads 5 and 19 μm average size and a mixture of both (0.7 volume fraction of large particles) were used to analyse starch composition by hydrodynamic chromatography (HDC), applying water as mobile phase. To obviate retrogradation, experiments were carried out at column temperatures of 15 and 3 °C and several types of starch were assayed. In what concerns amylopectin and amyl...

Permeability analysis in bisized porous media: wall effect between particles of...

The permeability of binary packings of glass beads with different size ratio – 13.3, 20, and 26.7, was investigated. In the Kozeny–Carman equation, the dependence of the tortuosity s on the mixture porosity e(xD) was described according to s = 1/en for different volume fraction of large particles in the mixture, xD. Obtained data on packing permeability shows that the parameter n is a function of the volume fra...