Skip to main content

Modeling dissolved air flotation

Buy Article:

$30.00 plus tax (Refund Policy)


Previously the flotation process was mainly characterized on an empirical basis. A model for dissolved air flotation (DAF) is presented that quantitatively describes the correlations and parameters used in both the contact and separation zones. This model includes two parameters, the bubble-floc attachment efficiency (α pb) and the air-to-solid volume ratio in the agglomerates(β). The sensitivity of the model for assumptions on physico-chemical and operational parameters and on the two parameters α pb and β is thereafter investigated.

Experimental flotation efficiencies in a coaxial DAF column under varying operational conditions were in excess of 90% at surface loadings of 15 m/h and in excess of 95% at 10 m/h.

The flotation model, combining bubble-filter and separation efficiencies, was thereafter used to predict the efficiencies, and the model parameters α pb and β were determined by a best fit-approach between model and experiment.

The model is not too sensitive to values of these parameters. The defined α pb and β values correspond with previous literature data although the concept of the coaxial DAF improves the efficiencies compared with traditional rectangular DAF-columns.

The model can be used to calculate the efficiency for various possible operating conditions using either parameter values selected within the range of this paper or parameter values determined by fitting a limited number of small-scale experiments.


Document Type: Research Article


Publication date: 1996-09-01

More about this publication?
  • Water Environment Research (WER) is published monthly, including an annual Literature Review. A subscription to WER includes access to the latest content back to 1992, as well as access to fast track articles. An individual subscription is valid for 12 months from month of purchase.

    Water Environment Research� (WER�) publishes peer-reviewed research papers, research notes, state-of-the-art and critical reviews on original, fundamental and applied research in all scientific and technical areas related to water quality, pollution control, and management. An annual Literature Review provides a review of published books and articles on water quality topics from the previous year.

    Published as: Sewage Works Journal, 1928 - 1949; Sewage and Industrial Wastes, 1950 - 1959; Journal Water Pollution Control Federation, 1959 - Oct 1989; Research Journal Water Pollution Control Federation, Nov 1989 - 1991; Water Environment Research, 1992 - present.
  • Editorial Board
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Membership Information
  • Information for Advertisers
  • WEF Bookstore
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more