FGD is a set of technologies used to remove sulphur-dioxide from exhaust flue gases of fossil-fuel power plants.

• Flue gases is mixture of gases produced by combustion of fuel and other materials in power stations and various industrial plants and released via flu (ducts) in atmosphere.
• It largely consists of oxides of nitrogen derived from combustion of air, Sulphur dioxide, carbon dioxide, carbon monoxide, water vapour, excess oxygen, particulate matter like soot.
• The technique was in news because state owned BHEL has bagged major order from the NTPC for setting up of FGD system at its power plant in UP.