URS Corporation will demonstrate the use of an additive in wet lime or limestone flue gas desulfurization (FGD) systems to prevent oxidized mercury that is absorbed from coal-fired flue gases in the FGD system from being reduced by the FGD liquor and “re-emitted” into the flue gas as elemental mercury. The additive also allows mercury removed in the wet FGD system to be precipitated as a stable salt that can be removed from the FGD byproducts and disposed of separately. Although the additive, Degussa Corporation’s TMT-15, is used extensively to prevent mercury re-emissions from wet FGD systems on municipal waste incinerators in Europe, this project will be the first known demonstration of the additive for this purpose for U.S. coals. The project will include additive testing in two pilot-scale and two full-scale FGD systems. The pilot units will be located at TXU Energy’s lignite-fired Monticello Station (Mt. Pleasant, TX) and at Georgia Power’s Plant Yates (Newnan, GA) which fires low-sulfur Eastern bituminous coal. The full-scale tests will be conducted at Indianapolis Power and Light's Petersburg Station (Petersburg, IN) which fires high-sulfur Eastern bituminous coal, and at Plant Yates. The project is being co-funded by EPRI, TXU Energy, Indianapolis Power and Light, the Southern Company, and Degussa Corporation.