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Abstract

A comparative analysis concerning the influence of different factors on momentum transfer in mechanically agitated systems was carried out on the basis of experimental results for solid-liquid, gas-liquid and gas-solid-liquid systems. The effects of the impeller - baffles system geometry, scale of the agitated vessel, type and number of impellers and their off-bottom clearance, as well as physical properties of the multiphase systems on the critical impeller speeds needed to produce suspension or dispersion, power consumption and gas hold-up were analysed and evaluated.

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Authors and Affiliations

Magdalena Cudak
Anna Kiełbus-Rąpała
Marta Major-Godlewska
Joanna Karcz
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Abstract

Efficiency of agitation was considered for different physical systems on the basis of our own experimental studies on homogenisation, heat and mass transfer as well as gas hold-up. Measurements were performed for different physical systems: Newtonian liquids of low and higher viscosity, pseudoplastic liquid, gas–liquid and gas–solid–liquid systems agitated in vessels of the working volume from 0.02 m3 to 0.2 m3. Agitated vessels of different design were equipped with a high-speed impeller (10 impellers were tested). Comparative analysis of the experimental results proved that energy inputs (power consumption) should be taken into account as a very important factor when agitation efficiency is evaluated in order to select a proper type of equipment. When this factor is neglected in the analysis, intensification of the process can be estimated only.
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Authors and Affiliations

Joanna Karcz
1
Jolanta Szoplik
1
ORCID: ORCID
Marta Major-Godlewska
1
Magdalena Cudak
1
Anna Kiełbus-Rapała
1

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, al. Piastów 42, 71-065 Szczecin, Poland

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