Toxic Substances from Coal Combustion: A Comprehensive Assessment: Quarterly report, 1 July 1996-30 September 1996

The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPS) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Pittsburgh Energy Technology Center (PETC), the Electric Power Research Institute (EPRI), and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UKy), the University of Connecticut, and Princeton University to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NO{sub x}, combustion systems, and new power generation plants. Development of ToPEM will be based on PSI`s existing Engineering Model for Ash Formation (EMAF). Extensive coal characterization and laboratory work has begun in order to develop and test new sub-models. Trace element concentrations in the Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 coals, and in size/density fractions of these coals, were completed. Coal characterization in the past quarter also included direct identification of the modes of occurrence of various trace inorganic species in coal and ash using unique analytical techniques such as XAFS analysis and selective leaching. Combustion testing of these two coals was begun and preliminary data obtained on trace element 0301 vaporization in the combustion zone. Modeling efforts in the past quarter include the development on a preliminary model to assess mercury speciation in combustion systems