<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>The follow up research into the IHDS process was carried out with a Couette device. The outcome of this study provides a comprehensive understanding of the effect that both the agitation intensity and the agitation time have on the kinetics and the mechanism of the aggregation process. The results obtained confirm the very favourable influence of high agitation intensity for the formation of more compact and dense aggregates than those formed by the accustomed flocculation conditions with low agitation intensity. This research also proved that the agitation intensity and time are the inherent means profoundly influencing the properties of the resultant aggregates such as their size, shape, density and homogeneity. Further, it was confirmed that the aggregation process passes through a minimum. Furthermore, it was verified that the aggregation process takes place in four consecutive phases, namely a) the phase of formation, b) the phase of compaction, c) the phase of a steady (equilibrium) state and d) most probably the phase of inner restructuring. The pattern of the aggregates development in these phases remains the same irrespective of the magnitude of the velocity gradient applied but the time at which these phases are completed is velocity gradient dependent. Last but not least this study proved that the dimensionless product <italic>Ca</italic> = <italic>G T</italic> = const. has no general validity.</p></abstract>

The follow up research into the IHDS process was carried out with a Couette device. The outcome of this study provides a comprehensive understanding of the effect that both the agitation intensity and the agitation time have on the kinetics and the mechanism of the aggregation process. The results obtained confirm the very favourable influence of high agitation intensity for the formation of more compact and dense aggregates than those formed by the accustomed flocculation conditions with low agitation intensity. This research also proved that the agitation intensity and time are the inherent means profoundly influencing the properties of the resultant aggregates such as their size, shape, density and homogeneity. Further, it was confirmed that the aggregation process passes through a minimum. Furthermore, it was verified that the aggregation process takes place in four consecutive phases, namely a) the phase of formation, b) the phase of compaction, c) the phase of a steady (equilibrium) state and d) most probably the phase of inner restructuring. The pattern of the aggregates development in these phases remains the same irrespective of the magnitude of the velocity gradient applied but the time at which these phases are completed is velocity gradient dependent. Last but not least this study proved that the dimensionless product Ca = G T = const. has no general validity.

Influence of Velocity Gradient on Optimisation of the Aggregation Process and Properties of Formed Aggregates

Institute of Hydrodynamics, Pod Patankou 5, 166 12 Prague 6, Czech Republic

Journal of Hydrology and Hydromechanics

The follow up research into the IHDS process was carried out with a Couette device. The outcome of this study provides a comprehensive understanding of the...

Influence of Velocity Gradient on Optimisation of the Aggregation Process and Properties of Formed Aggregates

Published Online: Sep 21, 2011

Page range: 196 - 205

DOI: https://doi.org/10.2478/v10098-011-0016-6

Keywords
průtoková tvorba vysoko hustotní suspenze, IHDS metoda, fáze agregačního procesu, vlastnosti agregátů, kompaktnost, relativní hustota agregátů

This content is open access.

Influence of Velocity Gradient on Optimisation of the Aggregation Process and Properties of Formed Aggregates

Published Online: Sep 21, 2011

Page range: 196 - 205

DOI: https://doi.org/10.2478/v10098-011-0016-6

Keywordsprůtoková tvorba vysoko hustotní suspenze, IHDS metoda, fáze agregačního procesu, vlastnosti agregátů, kompaktnost, relativní hustota agregátů

This content is open access.

Keywords
průtoková tvorba vysoko hustotní suspenze, IHDS metoda, fáze agregačního procesu, vlastnosti agregátů, kompaktnost, relativní hustota agregátů