Recent applications of dissolved air flotation pilot studies and full scale design

Abstract

The use of Dissolved Air Flotation (DAF) as a solids/liquid separation process in water treatment has been an effective alternative to sedimentation for 70 years. The process was initially applied for removal of materials which had a specific gravity less than water, such as fats, oils, fibers, and grease. DAF installations expanded in the late 1960s to wastewater and potable water treatment. Today, Dissolved Air Flotation is utilized for a wide variety of water and wastewater applications. DAF is applied extensively for wastewater sludge thickening and it is widely accepted in Scandinavia and the United Kingdom for potable water treatment. It has also gained a foothold in the United States with the start up of a 7.5 mgd (28.4 Ml/d) potable water flotation plant at New Castle, New York. The goal of this paper is to present recent applications of Dissolved Air Flotation technology on a variety of raw water sources. Descriptions and general design parameters of a typical flotation and a proprietary combined flotation and filtration process will be discussed.