Coal reporting analytical data

A wide range of bituminous coals, representing most of the major U. S. coal fields, were microscopically and chemically analyzed in this study. The samples tested, approximately 200 in all, were obtained through various coal producers. However, analytical data were not available for all samples carbonization, chemical, and by-product gas data for these subject coals were assumed to be the same as those reported previously in published sources (7, 9910,11,17,18). Only those carbonization data obtained from tests conducted in 18-inch pilot coke ovens at 900°C. are included. The remaining analytical data, approximately one-tenth of the total test results, were obtained from full scale commercial coke oven tests. Because these latter data were not sufficiently represented in the study, they were not considered in computing correlation coefficients (r). 

Just as a relationship exists between the various properties of petroleum with parameters such as depth of burial of the reservoir (Speight, 1999), similar relationships exist for the properties of coal (e.g., Solomon, 1981 Speight, 1994). Variations in hydrogen content with carbon content or oxygen content with carbon content and with each other have also been noted. However, it should be noted that many of the published reports cite the variation of analytical data or test results not with rank in the true sense of the word but with elemental carbon content that can only be approximately equated to rank. 

Bragg, L. J., Oman, J. K., Tewalt, S. J., Oman, C. J., Rega, N. H., Washington, N. H., and Finkelman, R. B. (1997). The COALQUAL CD-ROM Analytical data, sample locations, and descriptive information, analytical methods and sampling techniques, database perspective, and bibliographic references for selected U.S. coal samples U.S. Geological Survey Open-File Report 97-134, CD-ROM. 

Because moisture and mineral matter (incorporating the ash) are extraneous to the coal substance, there are different ways to report the analytical data... 

Jhe distribution of hydrogen types in coals continues to be a subject of considerable interest in coal structure studies. Published data indicate that the fraction of aromatic hydrogens usually increases with increasing rank, but the absolute values depend on the specific analytical method used (7). Hydrogen type analysis of a single coal based on the application of NMR spectroscopy to the soluble fraction from depolymerization with phenol-BFa has been reported by us (3). The conversion of coal to soluble fragments in substantial yields under very mild conditions permits a reliable determination of the hydrogen types by NMR analysis, and these results can be extrapolated to the parent coal with considerable confidence. 

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