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  2. Coal mining - Wikipedia

    en.wikipedia.org/wiki/Coal_mining

    A coal mine mantrip at Lackawanna Coal Mine in Scranton, Pennsylvania Coal miners exiting a winder cage at a mine near Richlands, Virginia in 1974 Surface coal mining in Wyoming, U.S. A coal mine in Frameries, Belgium. Coal mining is the process of extracting coal from the ground or from a mine.

  3. Mountaintop removal mining - Wikipedia

    en.wikipedia.org/wiki/Mountaintop_removal_mining

    Mountaintop removal mining (MTR), also known as mountaintop mining (MTM), is a form of surface mining that involves the topographical alteration and/or removal of a summit, hill, or ridge to access buried coal seams. The MTR process involves the removal of coal seams by first fully removing the overburden lying atop them, exposing the seams ...

  4. Coal gasification - Wikipedia

    en.wikipedia.org/wiki/Coal_gasification

    During gasification, the coal is blown through with oxygen and steam (water vapor) while also being heated (and in some cases pressurized). If the coal is heated by external heat sources the process is called "allothermal", while "autothermal" process assumes heating of the coal via exothermal chemical reactions occurring inside the gasifier ...

  5. Mineral processing - Wikipedia

    en.wikipedia.org/wiki/Mineral_processing

    Mineral processing is the process of separating commercially valuable minerals from their ores in the field of extractive metallurgy. [1] Depending on the processes used in each instance, it is often referred to as ore dressing or ore milling .

  6. Coal - Wikipedia

    en.wikipedia.org/wiki/Coal

    The coal mining industry employs almost 2.7 million workers. [107] ... Coal homogenization – Process of mixing coal to reduce variance; Coal measures ...

  7. Coal preparation plant - Wikipedia

    en.wikipedia.org/wiki/Coal_preparation_plant

    This is the raw material for the CPP, and consists of coal, rocks, middlings, minerals and contamination. Contamination is usually introduced by the mining process and may include machine parts, used consumables and parts of ground engaging tools. ROM coal can have a large variability of moisture and maximum particle size.

  8. Underground coal gasification - Wikipedia

    en.wikipedia.org/wiki/Underground_coal_gasification

    Underground coal gasification (UCG) is an industrial process which converts coal into product gas. UCG is an in-situ gasification process, carried out in non-mined coal seams using injection of oxidants and steam. The product gas is brought to the surface through production wells drilled from the surface. [1]

  9. Mining - Wikipedia

    en.wikipedia.org/wiki/Mining

    Some mining methods (lithium mining, phosphate mining, coal mining, mountaintop removal mining, and sand mining) may have such significant environmental and public health effects that mining companies in some countries are required to follow strict environmental and rehabilitation codes to ensure that the mined area returns to its original ...