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Features of Anthracite

1. Freshly mined anthracite usually has a moisture content of less than 15%. On a moist, mineral-matter-free basis.
2. The heat content of anthracite varies from 26 to 33 MJ/kg (22 to 28 million Btu/short tonne). On an as-received basis, the heat content of anthracite coal consumed in the United States averages 29 MJ/kg (25 million Btu/ton) (i.e., containing both inherent moisture and mineral matter). 
3. Density of anthracite is 1.3-1.8 g/cm3.
4. The hardness of anthracite on the Mohs scale is 2.2-3.8.
5. The moisture content of anthracite coal is 0.5-4%.
6. The pH of a water suspension of anthracite is 7-7.8.
7. Volatile content is 0.5-20% in anthracite.
8. The resistivity of anthracite is 1×10−3 to 2×105 Ω-m.
9. Anthracite refuse or mine waste has been used for coal power generation as a method of recycling since the 1980s.

Anthracite is a chemical intermediate between ordinary bituminous coal and graphite, formed by the more or less complete removal of the volatile constituents of the former, and it is most abundant in areas subjected to significant stresses and pressures, such as the flanks of large mountain ranges. Anthracite is associated with highly deformed sedimentary rocks exposed to higher pressures and temperatures (but not metamorphic conditions), whereas bituminous coal is associated with less deformed or flat-lying sedimentary rocks.

Deep mined compressed layers of anthracite in the folded Ridge and Valley Province of the Appalachian Mountains of East-central Pennsylvania, for example, are extensions of the same layers of bituminous coal. These are mined on the Allegheny Plateau of Kentucky and West Virginia, Eastern Ohio, and Western Pennsylvania, where the sedimentary rocks are mostly smooth and undeformed. Similarly, South Wales' anthracite area is limited to the twisted section west of Swansea and Lanelle, with the central and eastern parts supplying steam coal, coking coal, and domestic house coals.

Anthracite's structure has been altered by the formation of secondary divisional planes and fissures, making the initial stratification lines difficult to see. The thermal conductivity is also higher; when kept in the warm hand, a lump of anthracite feels noticeably colder than a comparable lump of bituminous coal at the same temperature. In the article coal, the chemical composition of some common anthracites is given. Anthracite resembles a mineraloid jet in appearance and is often used as a jet substitute.

Reserves of Anthracite

Russia, China, and Ukraine have the largest estimated recoverable anthracite reserves among current producers. Vietnam and North Korea are two other countries with significant reserves.

The Lackawant to Coal Mine in northeastern Pennsylvania, United States, in and around Scranton, Pennsylvania, is home to the world's largest and most concentrated anthracite deposit. The deposit, known locally as the Coal Region, spans 480 square miles (1,200 square kilometres) of coal-bearing rock that once contained 22.8 billion short tonnes (20.68 billion tonnes) of anthracite. The geographical area is approximately 100 miles (161 kilometres) long and 30 miles (48 kilometres) wide. It is estimated that 7 billion short tonnes (6.3 billion tonnes) of mineable reserves remain due to historical mining and growth of the lands overlying the coal. Smaller anthracite deposits, such as those traditionally mined in Crested Butte, Colorado, can also be found in the United States.

The Groundhog Anthracite Deposit is the world's largest previously undeveloped anthracite deposit, found in British Columbia, Canada. It is owned by Atrum Coal, an Australian publicly traded corporation with 1.57 billion tonnes of high-grade anthracite.

Anthracites from the Tertiary or Cretaceous period have been discovered in the Crowsnest Pass region of the Rocky Mountains in Canada, as well as in the Andes of Peru.

Mining Sites of Anthracite

China currently mines the vast majority of the world's anthracite, accounting for more than three-quarters of total production. The majority of anthracite produced in China is of standard grade, which is used in power generation. Increased demand in China has turned the country into a net importer of the fuel, primarily from Vietnam, another major producer of anthracite for power generation, though Vietnam's exports may be curtailed due to rising domestic consumption.

Anthracite production in the United States is currently about 5 million tonnes per year. The state of Pennsylvania mined about 1.8 million tonnes of that total. Anthracite coal mining is still going strong in eastern Pennsylvania, contributing up to 1% of the state's gross domestic product. In 1995, over 2,000 workers worked in the anthracite coal mining industry. The majority of the mining at the time involved reclaiming coal from nearby closed mines' slag heaps (waste dumps from previous coal mining). There is also some underground anthracite coal being mined.

Russia and South Africa are two countries that produce HG and UHG anthracite. In various metallurgical coal applications, HG and UHG anthracite are used as a coke or coal replacement (sintering, PCI, direct BF charge, pelletizing). It's used to make ferroalloys, silicomanganese, calcium carbide, and silicon carbide, as well as ferroalloys, silicomanganese, calcium carbide, and silicon carbide. Lower-quality, higher-ash anthracite is exported from South Africa to Brazil for use in steel production.

Source:  https://www.vedantu.com/chemistry/anthracite