RI 8118 Sulfur Reduction Potential of the Coals of the United States - A Revision of Report of Investigations 7633

This report presents the results of a washability study of 455 raw coal channel samples with special emphasis on sulfur reduction. These raw coals contained on the average 14.0 percent ash, 1.91 percent pyritic sulfur, and 3.02 percent total sulfur. The complete washability data are presented for each sample processed. A statistical evaluation is included for the coalbeds from which more than 10 samples were collected and for the geographical coal producing regions. A graphical summation is presented for the coal producing regions and selected coalbeds. Finally a similar statistical evaluation is included showing composited data interpolated at Btu recovery levels of 50, 60, 70, 80, 90, and 100 percent. Graphical summations are presented for the various coal producing regions. Generally, significant sulfur reduction is achieved if the coals are crushed to a finer size and the higher specific gravity increments are removed. If a 50-percent Btu recovery was acceptable, then 32 percent of the samples tested could be upgraded to meet the current Environmental Protection Agency (EPA) standard of 1.2 pounds of S02 emission per million (MM) Btu when crushed to 14-mesh top size and separated gravimetrically.