Generation of aqueous foams and fiber foams in a stirred tank

Jarmo Kouko (Corresponding Author), Baranivignesh Prakash, Veli-Matti Luukkainen, Ari Jäsberg, Antti I. Koponen

Research output: Contribution to journalArticleScientificpeer-review

4 Citations (Scopus)


Generation of fiber foams with surface aeration was studied by simultaneous mixing of pulp fibers, surfactant, air and water in a lab-scale tank. The mixing took place in either transient or turbulent conditions. The effect of impeller type (RT-6 and BT-6), mixing speed, mixing power, and surfactant dosage on air content, bubble size and half-life time of the foam was investigated. Air content increased with increasing agitation power saturating to 50–75% depending on the SDS dosage. The dependence of bubble size on power was a power law with an exponent typical for processes where coalescence plays an important role. The relation between the half-life time and air content was well described by a power law. Power number of the BT-6 impeller was almost constant, and similar to that of pure water in turbulent conditions. The power number of the RT-6 impeller varied and was similarly to gas-liquid stirred tanks, in many cases clearly below that of water. The variability of the power number of RT-6 could be explained with the variation of the mixing Reynolds number.
Original languageEnglish
Pages (from-to)15-24
JournalChemical Engineering Research and Design
Publication statusPublished - Mar 2021
MoE publication typeA1 Journal article-refereed


  • Aqueous foam
  • fiber foam
  • mixing tank
  • radial impeller
  • air content
  • bubble size


Dive into the research topics of 'Generation of aqueous foams and fiber foams in a stirred tank'. Together they form a unique fingerprint.

Cite this