Optimising dissolved air flotation/filtration treatment of algae-laden lagoon effluent using surface charge: A Bolivar treatment plant case study

Russell K L Yap, Michael Holmes, William L Peirson, Michael Whittaker, Richard Stuetz, Bruce Jefferson, Rita K Henderson

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4 Citations (Scopus)


Dissolved air flotation (DAF) incorporating filtration (DAFF) is used at the Bolivar wastewater treatment plant (WWTP) to polish lagoon effluent for reuse. Elevated algal populations are frequently experienced and can lead to increased coagulant requirements and process control issues. Streaming current detectors (SCDs) and a charge demand analyser (CDA) were used to monitor the full-scale plant. This was followed by an optimisation study using a pilot plant with a CDA. It was found that the normal operational charge demand range for DAF at Bolivar was between -46 and -40 μeq L-1. Decreasing the pH of coagulation reduced coagulant consumption and facilitated more sensitive CDA responses to changes in alum dose.

Original languageEnglish
Pages (from-to)1684-1690
Number of pages7
JournalWater Science and Technology
Issue number8
Publication statusPublished - 2012
Externally publishedYes


  • Charge demand
  • Dissolved air flotation
  • Streaming current
  • Surface charge

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