What is the primary purpose of dissolved air flotation in a wastewater treatment plant?

The primary purpose of dissolved air flotation (DAF) in a wastewater treatment facility is grease removal. This treatment process is particularly effective for removing suspended solids, oils, and greases from wastewater. In DAF systems, air is dissolved in the wastewater under pressure and then released at atmospheric pressure, causing microscopic air bubbles to form. These bubbles attach to the grease and other particles, causing them to float to the surface. This floating mass, known as "float," can then be skimmed off, effectively separating it from the liquid phase.

While sludge thickening, nutrient removal, and pathogen elimination are important processes in wastewater treatment, they require different methods and technologies. For instance, sludge thickening usually involves gravity thickening or mechanical means, nutrient removal is typically accomplished through biological processes or chemical precipitation, and pathogen elimination may involve disinfection techniques such as chlorination or UV treatment. DAF is specifically designed for the efficient removal of grease and other floatable contaminants, making it a specialized tool in the wastewater treatment process.