A critical review of published coal quality data from the southwestern part of the Powder River Basin, Wyoming

Abstract

A review of publicly available coal quality data during the coal resource assessment of the southwestern part of the Powder River Basin, Wyoming (SWPRB), revealed significant problems and limitations with those data. Subsequent citations of data from original sources often omitted important information, such as moisture integrity and information needed to evaluate the issue of representativeness. Occasionally, only selected data were quoted, and some data were misquoted. Therefore, it was important to try to resolve issues concerning both the accuracy and representativeness of each available dataset. The review processes demonstrated why it is always preferable to research and evaluate the circumstances regarding the sampling and analytical methodology from the original data sources when evaluating coal quality information, particularly if only limited data are available. Use of the available published data at face value would have significantly overestimated the coal quality for all the coal fields from both the Fort Union and Wasatch Formations in the SWPRB assessment area. However, by using the sampling and analytical information from the original reports, it was possible to make reasonable adjustments to reported data to derive more realistic estimates of coal quality.

Properties of Torrefied U.S. Waste Blends

“…From an energy perspective, except plastic wastes with very high heat content ∼ 36 MJ/kg, the rest have heat values in the range 15-17 MJ/kg. The weighted average heat content in U.S. waste is ∼21 MJ/kg, which is comparable to that of Powder River Basin (PRB) coal that has a heat content of ∼17-19 MJ/kg (Luppens, 2011). This indicates that 1 dry ton of U.S. waste can replace 1 ton of PRB coal.…”

Assessment of coal geology, resources, and reserves in the Southwestern Powder River Basin, Wyoming

“…More realistic estimates of ranges in coal quality from thee Glenrock and Dry Cheyenne coal fields would be: moisture, 26.0-29.0 percent; ash, 7.5-12.0 percent; sulfur, 0.4-0.6 percent; and gross calorific values, 7,500-8,000 Btu/lb (Luppens, 2011). These coal quality estimates are significantly lower than would be projected from the published data.…”

“…All samples from mines in the Sussex coal field were low ash benches avoiding higher ash partings in each of the mined coal beds (Luppens, 2011). The presence of high ash partings is very common in the Sussex coal field (Wegemann, 1912).…”

Assessing U.S. coal resources and reserves

“…This information is used in academia and industry and by a variety of Federal and State agencies and contributes to the formulation of energy strategies, environmental policies, land-use management practices, and economic projections. • Geospatial Data for Coal Beds in the Powder River Basin, Wyoming and Montana (Kinney and others, 2015) • Drill Hole Data for Coal Beds in the Powder River Basin, Montana and Wyoming • Assessment of Coal Geology, Resources, and Reserve Base in the Powder River Basin, Wyoming and Montana • Assessment of Coal Geology, Resources, and Reserves in the Montana Powder River Basin (Haacke and others, 2013) • A Critical Review of Published Coal Quality Data from the Southwestern Part of the Powder River Basin, Wyoming (Luppens, 2011) • Assessment of Coal Geology, Resources, and Reserves in the Southwestern Powder River Basin, Wyoming (Osmonson and others, 2011) • Assessment of Coal Geology, Resources, and Reserves in the Northern Wyoming Powder River Basin (Scott and others, 2011) • Assessment of Coal Geology, Resources, and Reserves in the Gillette Coalfield, Powder River Basin, Wyoming (Luppens and others, 2012) Panoramic view of surface mine operation in the Powder River Basin, Wyoming. (Photo by David C. Scott)…”