DAF (dissolved air flotation) systems are used to separate suspended solids, oil and grease from wastewater. pollutants, treated DAF It is removed by using air solution in dissolved water produced by introducing compressed air into the recycling stream of waste. This recycle stream is then combined and mixed with incoming wastewater in a contact chamber, where dissolved air comes out of solution in the form of micron-sized bubbles that adhere to contaminants. Bubbles and contaminants rise to the surface and form a floating bed of material that is removed by a surface skimmer into an internal hopper for further processing.