DAF, acronym for Dissolved Air Flotation, is a water treatment process used in various industries, mainly for wastewater treatment or clarification of liquids. It operates by introducing air or gas, which is mostly in a dissolved state, into a liquid stream or slurry. The process works by creating tiny bubbles that attach to the suspended particles, solids, or colloids present in the liquid, ultimately causing them to float to the surface for removal.
The DAF process typically involves the use of a flotation tank or basin, where the wastewater flows in and is subjected to the introduction of pressurized air or recycled water with dissolved air. By increasing the pressure, the air molecules dissolve into the liquid, and when the pressure is released, these air molecules form small bubbles. These bubbles cause the suspended particles to rise to the surface of the tank due to buoyancy, forming a layer of sludge or froth, known as the float.
The float can then be skimmed off the surface of the water using mechanical means or with the assistance of inclined plates or other specialized techniques. The clarified water is collected from the bottom of the tank and directed for further processing or discharge.
DAF is widely used in industrial and municipal wastewater treatment plants as an effective and efficient method to remove contaminants and solids from water, such as fats, oils, grease, algae, suspended solids, and various organic and inorganic matter. It provides a reliable and cost-effective solution for achieving higher water quality standards and compliance with environmental regulations.
