A review of the technological developments of dissolved air flotation

This paper gives a review of current dissolved air flotation (DAF) technology and its application to the municipal sector, particularly drinking water production and, to a lesser extent, wastewater treatment. An explanation of the DAF process is given and issues arising from the technology are discussed. A history of the development of DAF is provided starting from its roots in Scandinavia, and its application in the UK, South Africa, Australia, Asia, and America. Application areas are discussed, using illustrative case studies, with an emphasis on municipal drinking water and wastewater applications. Recent technological advances in reduction of flocculation hydraulic detention times and new proprietary DAF processes are discussed - for example, CoCoDAFF (TM), DAFRapide (TM) and AquaDAF (TM). The conclusions suggest areas for future development work, mainly in improving energy efficiency in micro-bubble production.