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Longwall Mining in Ultrathick U.S. Coal Seams.

Ahcan R; Zerdin F; Lutzens WW
Paper in Proceedings Longwall USA Maclean Hunter PP 243-264 :243-264
As part of the U.S. Bureau of Mines participation in the United States-Yugoslavia Joint Scientific and Technology Cooperation Program. Yugoslavian mining methods currently being used to mine ultrathick 300-ft (91.5-M) underground lignite deposits were evaluated for future mining of ultrathick U.S. coal seams. Bureau of Land Management surface-minerals management status maps were used to locate a mine site for a hypothetical mine in the Wyoming Powder River Basin where the ground surface and the underground minerals are owned by the U.S. Government. The coal deposit in the area of the selected site, where the Anderson and Canyon coal seams are joined, is approximately 182 ft (55.5 M) thick, 1,000 ft (304.9 M) below the surface, and is estimated to contain 113 billion tons of coal. A mining system was applied to the hypothetical mine, based on the Yugoslavian "longwall sublevel caving" mining method. "Longwall sublevel caving" is a mining method where roof coal is rubblized above the shields and allowed to flow through a trap door in the top of the shields. The coal is subsequently directed either to the face conveyor or to a second conveyor inside the shields. Multiple 32.8-Ft (10-m) "slices" are successively mined from top to bottom to extract an entire ultrathick coal seam. The potential for applying this Yugoslavian longwall mining technique to the ultrathick Wyoming Anderson-Canyon coal seam is evaluated.
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OP 189-91
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Paper in Proceedings, Longwall Usa. Maclean Hunter, PP. 243-264
Page last reviewed: October 8, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division