What is "bituminous coal"

Bituminous \Bi*tu"mi*nous\, a. [L. bituminosus: cf. F. bitumineux.] Having the qualities of bitumen; compounded with bitumen; containing bitumen.

Near that bituminous lake where Sodom flamed.
--Milton.

Bituminous coal, a kind of coal which yields, when heated, a considerable amount of volatile bituminous matter. It burns with a yellow smoky flame.

Bituminous limestone, a mineral of a brown or black color, emitting an unpleasant smell when rubbed. That of Dalmatia is so charged with bitumen that it may be cut like soap.

Bituminous shale, an argillaceous shale impregnated with bitumen, often accompanying coal.

Coal \Coal\ (k[=o]l), n. [AS. col; akin to D. kool, OHG. chol, cholo, G. kohle, Icel. kol, pl., Sw. kol, Dan. kul; cf. Skr. jval to burn. Cf. Kiln, Collier.]

1. A thoroughly charred, and extinguished or still ignited, fragment from wood or other combustible substance; charcoal.

2. (Min.) A black, or brownish black, solid, combustible substance, dug from beds or veins in the earth to be used for fuel, and consisting, like charcoal, mainly of carbon, but more compact, and often affording, when heated, a large amount of volatile matter. Note: This word is often used adjectively, or as the first part of self-explaining compounds; as, coal-black; coal formation; coal scuttle; coal ship. etc. Note: In England the plural coals is used, for the broken mineral coal burned in grates, etc.; as, to put coals on the fire. In the United States the singular in a collective sense is the customary usage; as, a hod of coal. Age of coal plants. See Age of Acrogens, under Acrogen. Anthracite or Glance coal. See Anthracite. Bituminous coal. See under Bituminous. Blind coal. See under Blind. Brown coal or Brown Lignite. See Lignite. Caking coal, a bituminous coal, which softens and becomes pasty or semi-viscid when heated. On increasing the heat, the volatile products are driven off, and a coherent, grayish black, cellular mass of coke is left. Cannel coal, a very compact bituminous coal, of fine texture and dull luster. See Cannel coal. Coal bed (Geol.), a layer or stratum of mineral coal. Coal breaker, a structure including machines and machinery adapted for crushing, cleansing, and assorting coal. Coal field (Geol.), a region in which deposits of coal occur. Such regions have often a basinlike structure, and are hence called coal basins. See Basin. Coal gas, a variety of carbureted hydrogen, procured from bituminous coal, used in lighting streets, houses, etc., and for cooking and heating. Coal heaver, a man employed in carrying coal, and esp. in putting it in, and discharging it from, ships. Coal measures. (Geol.)

   1. Strata of coal with the attendant rocks.

   2. A subdivision of the carboniferous formation, between the millstone grit below and the Permian formation above, and including nearly all the workable coal beds of the world.

      Coal oil, a general name for mineral oils; petroleum.

      Coal plant (Geol.), one of the remains or impressions of plants found in the strata of the coal formation.

      Coal tar. See in the Vocabulary.

      To haul over the coals, to call to account; to scold or censure. [Colloq.]

      Wood coal. See Lignite.

n. rich in tarry hydrocarbons; burns readily with a smoky yellow flame [syn: soft coal]

Bituminous coal or black coal is a relatively soft coal containing a tarlike substance called bitumen. 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 stratigraphically identified.

Bituminous coal is an organic sedimentary rock formed by diagenetic and sub metamorphic compression of peat bog material. Its primary constituents are macerals: vitrinite, and liptinite. The carbon content of bituminous coal is around 60-80%; the rest is composed of water, air, hydrogen, and sulphur, which have not been driven off from the macerals. 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.