Advanced Technologies for the Control of Sulfur Dioxide Emissions from Coal-Fired Boilers

Executive Summary The Clean Coal Technology (CCT) Program is a government and industry cofunded effort to demonstrate a new generation of innovative coal utilization processes in a series of " showcase " facilities built across the country. These projects are carried out on a scale sufficiently large to demonstrate commercial worthiness and to generate data for design, construction, operation, and technical/economic evaluation of full-scale commercial applications. The goal of the CCT Program is to furnish the U.S. energy marketplace with a number of advanced, more efficient coal-based technologies meeting strict environmental standards. These technologies will mitigate the economic and environmental impediments that limit the full utilization of coal as a continuing viable energy resource. To achieve this goal, beginning in 1985, a multiphased effort consisting of five separate solicitations was administered by the U.S. Department of Energy's (DOE) Federal Energy Technology Center (FETC). Projects selected through these solicitations have demonstrated technology options with the potential to meet the needs of energy markets while satisfying relevant environmental requirements. Part of this program is the demonstration of technologies, referred to as flue gas desulfurization (FGD) processes, designed to reduce sulfur dioxide (SO 2) emissions from coal-fired power plants. Emissions of SO 2 , a precursor of acid rain, are regulated under the provisions of the 1990 Clean Air Act Amendments (CAAA). This Topical Report discusses three completed CCT projects that successfully demonstrated SO 2 emissions reductions via innovative FGD processes. The goal of all three projects was to achieve greater than 90% SO 2 removal. This goal was achieved, with SO 2 removals as high as 98% being demonstrated. High particulate removal efficiencies were also achieved. In addition, these processes demonstrated the capability of producing wallboard-quality gypsum, a marketable by-product, thereby eliminating the need for FGD sludge disposal, a major problem for many conventional FGD processes. The scrubber was of unique design, incorporating cocurrent flow of gas and liquid. Coal sulfur content varied between 2.3% and 4.5%, typical of high-sulfur bituminous coals. A total of 210,000 tons of high-quality gypsum was produced during the demonstration and sold to a wallboard manufacturer. • Innovative Applications for the CT-121 FGD Process was demonstrated at Georgia Power's Plant Yates, Newnan, Georgia, using a novel scrubber called a jet bubbling reactor. This single process vessel replaces the usual spray tower/ reaction tank/thickener arrangement. The fiberglass-reinforced plastic used as the construction material proved highly corrosion resistant. Coal …