The report gives results of economic evaluations of two processes: the Rockwell International aqueous carbonate process (ACP) and the Wellman-Lord process, the latter applied to a sulfuric acid plant, the Foster Wheeler Resox process, and the Allied Chemical coal reduction process, all for sulfur production. The ACP uses a spray dryer flue gas desulfurization (FGD) system and molten salt reduction with coal to make sulfur. For a 500-MW power plant burning 3.5% sulfur coal, capital investments for the ACP and the Wellman-Lord (acid, Resox, and Allied) processes are $119, $131, $138, and $141/kW, respectively. Annual revenue requirements are 4.81, 5.11, 6.03, and 5.94 mills/kWh, respectively. The ACP has a major cost advantage because it incorporates final fly ash and chloride removal as process functions. Fly ash removal credits and Wellman-Lord chloride control costs essentially determine the capital investment relationships of the processes. The ACP has a major advantage in annual revenue requirements because it does not need process or reheat steam. Wellman-Lord process costs are the same for all three applications. The cost difference results from end plant costs to produce acid or sulfur. The cost relationship could be affected by further development. The ACP, Resox, and Allied processes have not been operated as commercial FGD systems.

"June 1981." Includes bibliographical references (pages 148-152). "TVA EDT-121." "EPA-IAG-D9-E721-B1." "Program element no. INE827."