The removal is achieved by injecting gas bubbles into the water or wastewater in a flotation tank or basin.
Induced gas flotation is very widely used in treating the industrial wastewater effluents from oil refineries, petrochemical and chemical plants, natural gas processing plants and similar industrial facilities.
IGF units in the oil industry do not use air as the flotation medium due to the explosion risk.
The feed water to the IGF float tank is often (but not always) dosed with a coagulant (such as ferric chloride or aluminum sulfate) to flocculate the suspended matter.
The froth-free water exits the float tank as the clarified effluent from the IGF unit.