Flotation

A technique for separating different solid particles in a liquid on the principle that some particles absorb water while others do not: the non-wetting particles attach to air bubbles and float. Used in mineral processing and in food applications such as removing contaminants from grain or recovering particles from effluents. Dissolved-air flotation saturates effluent with air under pressure, then releases it as microbubbles that lift fats, oils and suspended solids to the surface for skimming — a standard primary treatment in food factories. In grain cleaning, aspiration and flotation tables separate stones and light impurities by density differences.