The utilization of flue-gas desulfurization materials

Abstract Flue-gas desulfurization (FGD) materials are solids generated when the SO 2 in exhaust gases from coal-fired power plants is removed before the gases are released to the atmosphere. Over 60 million tons of FGD materials are generated annually in the United States, about half of which is used beneficially. Mine reclamation accounts for about half of beneficially used FGD, and the FGD gypsum used in the production of wallboard utilizes the next largest volume of FGD. Cement manufacture, construction of structural fills, and agricultural applications each utilizes significant volumes of FGD products. The current utilization of FGD material, which is about 50%, is expected to increase incrementally over the next decade, with the greatest volumes being in wallboard manufacture and the greatest gains in percentage use being in agricultural applications.