Precombustion removal of hazardous air pollutant precursors. Third quarterly technical progress report, April 1, 1996--June 30, 1996

This project involves the development of an optimized, bench-scale processing circuit capable of efficiently removing trace elements from run-of-mine coals. The optimized circuit will be developed using characterization data obtained from detailed washability studies and release analyses tests conducted with several eastern US coals. The optimized circuit will incorporate a variety of conventional and advanced coal cleaning processes which are believed to be the most cost-effective and commercially viable. The coal products from the optimized circuit will be further treated with complexing agents specifically designed to extract organometallic trace elements that are difficult to remove by physical cleaning operations. Finally, innovative bioremediation schemes will be investigated as a means of controlling the release of trace elements from the process waste streams. Emphasis has been placed on the development of a processing circuit which maximizes the rejection of trace elements, minimizes the production of coal fines which are costly to process and less marketable, and minimizes the downstream impacts of the process waste streams on the environment. During the past quarter, the project work plan and all associated technical/management reports were successfully approved. Activities associated with the selection and acquisition of all three base coal samples have also been completed. Characterization work is continuing to move ahead at an accelerated pace in both Subtask 3.2--Washability Analysis and Subtask 3.3-- Flotation Release Analyses. In addition, mineralogical analyses are underway as part of the characterization work. In Task 4--Bench-Scale Testing, the experimental program is now well underway to assess the trace element cleanability of the Pittsburgh No. 8 coal. Effort has also been initiated under Task 4--Toxics Fate Studies to identify viable methods for controlling the release of trace metals from refuse samples for the Pittsburgh No. 8 seam