Flue Gas Desulfurization (FGD) is a current state-of-the art technology used for removing sulfur dioxide (SO2) from the exhaust flue gases. This is employed in power plants that burn coal or oil to generate the steam for the steam turbines for driving electricity generators. Sulfur dioxide is responsible for acid rain formation. Tall flue gas stacks disperse the emissions by diluting the pollutants in ambient air. These FGD systems are custom designed to remove sulfur dioxide from flue gases using a variety of reagents such as caustic, lime, limestone, ammonia, fly ash, magnesium oxide, soda ash as well as seawater or double alkali.