Brown, R. C.
Fan, M.
Department of Energy, 9/1/2000 to 8/31/2003
The overall objective of this research is to develop sulfur-based products from sulfur dioxide that are generated during gas-stream cleanup in advanced power systems. Specifically, we will explore the synthesis of polymeric ferric sulfate (PFS), an aluminum-free flocculating agent, from sulfur dioxide. Integration of PFS synthesis with an electric power plant would be an important step toward realizing coal refineries, a concept in which every waste stream becomes a feedstock for another process. The conversion of coal to electricity currently generates vast quantities of sulfur-laden waste streams, either as gaseous sulfur dioxide emitted to the atmosphere or as solid or sludge containing calcium sulfate, which is typically landfilled. Advanced coal conversion technologies will effectively remove sulfur from coal, but in the process generate a concentrated stream of sulfur dioxide. Industrial ecology principles would mandate the conversion of this sulfur dioxide into a high-value product for market. Sulfuric acid is an obvious product from sulfur dioxide, but the market price for this commodity chemical does not encourage new capital investment for its production. We propose the synthesis of PFS from sulfur dioxide. Polymeric ferric sulfate is a flocculating agent that has been widely adopted for water treatment in some parts of the world because of public health concerns about aluminum-based flocculating agents. Several medical studies implicate aluminum as an agent in the development of Alzheimer's disease. The prospect for addressing both air pollution and water pollution problems in the United States through the synthesis and application of PFS is an exciting one. However, several issues must be resolved before this technology becomes a reality. Specific research objectives include the following: (1) Optimize synthesis of PFS from the sulfur dioxide product of coal-based power systems. As part of this objective, a reaction mechanism for PFS synthesis will be developed; (2) Improve characterization of PFS product. Quality indices currently used to characterize PFS synthesis will be related to the structure of these inorganic polymers; (3) The role of product drying will be related to the amorphous structure of PFS and its ultimate flocculation performance; (4) Optimize application of PFS to different kinds of drinking water and wastewater. The market for PFS would be greatly expanded if its efficacy in removing heavy metals could be explicitly demonstrated. The proposed study includes three key activities: synthesis, characterization, and application of PFS. The project will be the joint effort of a team consisting of Iowa State University (ISU), the University of South Carolina (USC), Alliant Energy Corporation, Des Moines Water Works (DMWW), and Commissioners of Public Works for the City of Charleston (CPW). Iowa State University will be the prime contractor for the project and lead the synthesis and characterization activities. The University of South Carolina will be subcontractor to ISU and lead the application activity. Alliant Energy will support economic and environmental analysis through an industrial internship for a student participating on the project. Des Moines Water Works and CPW will provide pilot plant facilities and personnel to test PFS synthesized at ISU as a flocculating agent under realistic conditions of water treatment. (Administered by Institute for Physical Research and Technology)
Plus, apparently S02 combines with water and O2 to make H2S04. Somehow. Ask chambers