Bituminous coal

Bituminous coal

Bituminous coal or black coal is a relatively soft coal containing a ratlike substance called bitumen or asphalt. It is of higher quality than

lignite coal but of poorer quality than anthracite. Formation is usually the result of high pressure being exerted on lignite. Its coloration can

be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams. These distinctive sequences,

which are classified according to either "dull, bright-banded" or "bright, dull-banded", is how bituminous coals are strati graphically

identified.

Bituminous coal is an organic sedimentary rock formed by genetic and sub metamorphic compression of peat bog material. Its primary

constituents are macerates: vitrine, and lignite. The carbon content of bituminous coal is around 60–80%; the rest is composed of water, air,

hydrogen, and sulfur, which have not been driven off from the macerates. Bank density is approximately 1346 kg/m³ (84 lb/ft³). Bulk density

typically runs to 833 kg/m³ (52 lb/ft³). The heat content of bituminous coal ranges from 24 to 35 MJ/kg (21 million to 30 million BTU per short

ton) on a moist, mineral-matter-free basis.

Within the coal mining industry, this type of coal is known for releasing the largest amounts of firedamp, a dangerous mixture of gases that can

cause underground explosions. Extraction of bituminous coal demands the highest safety procedures involving attentive gas monitoring, good

ventilation and vigilant site management.

Uses

Smithing coal is a type of high-quality bituminous coal ideally suited for use in a coal forge. It is as free from ash, sulfur, and other

impurities as possible. The constituents of the coal should be as follows:

Cannel coal

Cannel coal is a coal which ignites easily producing a bright flame. The name derives from the Scottish pronunciation of candle coal. It contains

a high volatile content, is non-coking and was a source for coal oil in West Virginia during the mid-1800s.[3] While the use of Channel has

greatly diminished over the past century, it is still valued by artists for its ability to be carved and polished into sculptures and jewelry.

Coking coal

When used for many industrial processes, bituminous coal must first be "coked" to remove volatile components. Coking is achieved by heating the

coal in the absence of oxygen, which drives off volatile hydrocarbons such as propane, benzene and other aromatic hydrocarbons, and some sulfur

gases. This also drives off a considerable amount of the contained water of the bituminous coal.

Coking coal (metallurgical coal) is used in the manufacture of steel, where carbon must be as volatile-free and ash-free as possible.

Coking coal is heated to produce coke, a hard, grey, porous material which is used to blast in furnaces for the extraction of iron from the iron

ore.

Bituminous coal by geologic period

Bituminous coal in the United States is between 100 and 300 million years old.

Cretaceous coals

In the United States, Cretaceous bituminous coals occur in Wyoming, Colorado and New Mexico.

In Canada, the Western Canada Sedimentary Basin of Alberta and British Columbia hosts major deposits of bituminous coal that formed in swamps

along the western margin of the Western Interior Seaway. They range in age from latest Jurassic or earliest Cretaceous in the Mist Mountain

Formation, to Late Cretaceous in the Gates Formation. The Intercontinental and Insular Coalfields of British Columbia also contain deposits of

Cretaceous bituminous coa

Jurassic coals

Extensive but low-value coals of Jurassic age extend through the Surat Basin in Australia, formed in an intracratonic sag basin, and contain

evidence of dinosaur activity in the numerous ash plies. These coals are exploited in Queensland from the Walloon Coal Measures, which are up to

15 m thick of sub-bituminous to bituminous coals suited for coking, steam-raising and oil cracking.

Triassic coals

Coals of Triassic age are known from the Clarence-Moreton and Ipswich Basins, near Ipswich, Australia and the Esk Trough. Coals of this era are

rare, and many contain fossils of flowering plants. Some of the best coking coals are Australian Triassic coals, although most economic deposits

have been worked out.

Permian coals

The second largest deposits of the world's bituminous coal are contained within Permian strata in Russia. Australian deposits in the Bowen Basin

in Queensland, the Sydney Basin and Perth Basin are Permian coal, where thicknesses in excess of 300 m are known. Current reserves and resources

are projected to last for over 200 years.

Australia exports the vast majority of its coal for coking and steel making in Japan. Certain Australian coals are the best in the world for

these purposes, requiring little to no blending. Some bituminous coals from the Permian and Triassic in Australia are also the most suitable for

cracking into oil.

Carboniferous coals

Much North American coal was created in subsiding areas adjacent to the Appalachian Mountains during the Pennsylvanian subperiod. A vast network

of swamps covered large parts of North America at this time and much of the organic material created in these wetlands accumulated to form thick

layers of peat (the precursor to coal) that were buried faster than they could decay.

Bituminous coal is mined in the Appalachian region, primarily for power generation. Mining is done via both surface and underground mines.

Pocahontas bituminous coal at one time fueled half the world's navies and today stokes steel mills and power plants all over the glob