subbituminous coal — Dark brown to black coal, intermediate in rank between lignite and bituminous coal. It contains less water and is harder than lignite, making it easier to transport, store, and use. It has lower heating value than bituminous coal, but its sulfur… … Universalium
coal — coalless, adj. /kohl/, n. 1. a black or dark brown combustible mineral substance consisting of carbonized vegetable matter, used as a fuel. Cf. anthracite, bituminous coal, lignite. 2. a piece of glowing, charred, or burned wood or other… … Universalium
coal classification — ▪ process any of various ways in which coal is grouped. Most classifications are based on the results of chemical analyses and physical tests, but some are more empirical in nature. Coal classifications are important because they provide… … Universalium
coal — I (New American Roget s College Thesaurus) n. ember, cinder; charcoal, briquette (see fuel). See heat. II (Roget s IV) n. 1. [Mineral fuel] Syn. mineral coal, coke, fossil fuel; see fuel . Types of coal include: hard coal, soft coal, charcoal,… … English dictionary for students
Coal Classification — In the United States, coals are classified by rank progressively from lignite (least carbonaceous) to anthracite (most carbonaceous) based on the proximate analyses of various properties (fixed carbon, volatile matter, heating value, and… … Energy terms
Coal producing districts — A classification of coal fields defined in the Bituminous Coal Act of 1937. The districts were originally established to aid in formulating minimum prices of bituminous and subbituminous coal and lignite. Because much statistical information… … Energy terms
Coal rank — The classification of coals according to their degree of progressive alteration from lignite to anthracite. In the United States, the standard ranks of coal include lignite, subbituminous coal, bituminous coal, and anthracite and are based on… … Energy terms
coal mining — Coal was very important in the economic development of Britain. It was used as fuel in the factories built during the Industrial Revolution and continued to be important until the 1980s. The main coalfields are in north east England, the north… … Universalium
Coal — Sedimentary Rock Anthracite coal Composition Primary carbon Secondary hydrogen, sulfur … Wikipedia
Coal by country — Coal reserves in BTUs as of 2009 Coal output in 2005 … Wikipedia
