Effect of particle hydrophobicity on particle and water transport across a flotation froth

Date

2005

Authors

Schwarz, S.
Grano, S.

Editors

Advisors

Journal Title

Journal ISSN

Volume Title

Type:

Journal article

Citation

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2005; 256(2-3):157-164

Statement of Responsibility

S. Schwarz, S. Grano

Conference Name

Abstract

Froth recovery measurements have been conducted in both the presence (three-phase froth) and absence (two-phase froth) of particles of different contact angles in a specially modified laboratory flotation column. Increasing the particle hydrophobicity increased the flow rate of particles entering the froth, while the recovery of particles across the froth phase itself also increased for particle contact angles to 63° and at all vertical heights of the froth column. However, a further increase in the contact angle to 69° resulted in lower particle recovery across the froth phase. The reduced froth recovery for particles of 69° contact angle was linked to significant bubble coalescence within the froth phase. The reduced froth recovery occurred uniformly across the entire particle size range, and was, presumably, a result of particle detachment from coalescing bubbles. Water flow rates across the froth phase also varied with particle contact angle. The general trend was a decrease in the concentrate flow rate of water with increasing particle contact angle. An inverse relationship between water flow rate and bubble radius was also observed, possibly allowing prediction of water flow rate from bubble size measurements in the froth. Comparison of the froth structure, defined by bubble size, gas hold-up and bubble layer thickness, for two- and three-phase froths, at the same frother concentration, showed there was a relationship between water flow rate and froth structure. © 2005 Elsevier B.V. All rights reserved.

School/Discipline

Dissertation Note

Provenance

Description

Access Status

Rights

© 2005 Elsevier B.V. All rights reserved.

License

Grant ID

Call number

Persistent link to this record