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  2. Coal mining - Wikipedia

    en.wikipedia.org/wiki/Coal_mining

    Coal refuse, also known as coal waste, rock, slag, coal tailings, waste material, rock bank, culm, boney, or gob, is the material left over from coal mining, usually as tailings piles or spoil tips. For every tonne of hard coal generated by mining, 400 kg (880 lb) of waste material remains, which includes some lost coal that is partially ...

  3. History of coal mining - Wikipedia

    en.wikipedia.org/wiki/History_of_coal_mining

    The technology was far in advance of any coal mining method in the late medieval period and was considered one of the industrial wonders of the age. [ 15 ] During the 17th century a number of advances in mining techniques were made, such as the use of test boring to find suitable deposits and chain pumps , driven by water wheels , to drain the ...

  4. Automated mining - Wikipedia

    en.wikipedia.org/wiki/Automated_mining

    For the first time completely deserted coal mining technology has been used by the Chinese concern «China National Coal Group Corp. (CME)» at the mine «Tang Shan Gou» (longwall mining, shearers, three lava, depth 200 m), and at the mine «Nan Liang» (one plow, depth 100 m). Both coal mines have coal layer thickness 1–1.7 m.

  5. Longwall mining - Wikipedia

    en.wikipedia.org/wiki/Longwall_mining

    Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6–6.0 m (2 ft 0 in – 19 ft 8 in) thick). The section of rock that is being mined, known as the longwall panel, is typically 3–4 km (1.9–2.5 mi) long, but can be up to 7.5 km (4.7 mi) long and 250–400 m (820–1,310 ft) wide.

  6. Coal - Wikipedia

    en.wikipedia.org/wiki/Coal

    Refined coal is the product of a coal-upgrading technology that removes moisture and certain pollutants from lower-rank coals such as sub-bituminous and lignite (brown) coals. It is one form of several precombustion treatments and processes for coal that alter coal's characteristics before it is burned.

  7. History of coal mining in the United States - Wikipedia

    en.wikipedia.org/wiki/History_of_coal_mining_in...

    In 1810, 176,000 short tons of bituminous coal, and 2,000 tons of anthracite coal, were mined in the United States. American coal mining grew rapidly in the early 1820s, doubling or tripling every decade. Anthracite mining overtook bituminous coal mining in the 1840s; from 1843 through 1868, more anthracite was mined than bituminous coal.