You are here:
CHEMICALLY ACTIVE FLUID BED FOR SOX CONTROL. VOLUME I. PROCESS EVALUATION STUDIES
Citation:
Keairns, D., W. Vaux, N. Ulerich, E. Vidt, AND R. Newby. CHEMICALLY ACTIVE FLUID BED FOR SOX CONTROL. VOLUME I. PROCESS EVALUATION STUDIES. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/7-79/158A.
Description:
The report describes selected process evaluation studies supporting the development of an atmospheric-pressure, fluidized-bed, chemically active gasification process, using a regenerative limestone sulfur sorbent to produce low- to intermediate-Btu fuel gas. Limestone sorbent selection and attrition, alternative metal oxide sorbents, particulate control, fuel supply, and an updated process assessment are investigated. Limestone sorbent selection results are presented for the EPA-sponsored CAFB demonstration plant. Sorbent attrition and economics are the main criteria as most limestone are not limited by sulfur removal. Trace element, regeneration, and disposal characteristics should be considered. Feasibility tests of air oxidation for disposal of gasifier solids for once-through operation show up to 70% conversion of the CaS. Methods for improving performance are identified. A procedure was developed to measure the attrition tendency of the sorbent selected. Brownwood limestone has intermediate attrition resistance showing 5.4% mass loss by attrition for this test, compared with three reference stones ranging from 0.5 to 9.1%. Sixteen alternative metal oxide sulfur sorbents that could reduce the environmental impact of solids disposal and may improve process economics were screened. CaO/CaO3, ZnO, and FeO are sorbents identified for further study.