PIXE microanalysis of Fe-sulfides: Comparison of eastern and western coals.

摘要

Several of the toxic-heavy metals listed for consideration in the Clean Air Acts Amendments of 1990 are strongly concentrated in Fe-sulfides, particularly Ni, As, Se, Hg, and Pb. This finding suggests that significant mitigation of utility emissions of these metals will result from pre-combustion beneficiation that removes Fe-sulfides from feed coals. The heterogeneities of individual metals in single channel samples suggests that in some seams only certain stratigraphic layers in a seam are likely to cause an environmental problem. Although initial results from the lower Kittanning coals suggest that sedimentological information might provides clues to As contents of coals, follow-up results from several coal seams with fresh-water affinities suggest that the result observed in the lower Kittanning is probably a special case.