Coke

/kook/, n.

Sir Edward, 1552-1634, English jurist and writer on law.

Also, Cooke.

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Solid residue remaining after certain types of coals are heated to a high temperature out of contact with air until substantially all components that easily vaporize have been driven off.

The residue is chiefly carbon, with minor amounts of hydrogen, nitrogen, sulfur, and oxygen. Also present in coke is the mineral matter in the original coal, chemically altered and decomposed. The gradual exhaustion of timber in England had led first to prohibitions on cutting of wood for charcoal and eventually to the introduction of coke. Thereafter the iron industry expanded rapidly and Britain became the world's greatest iron producer (see Abraham Darby). The crucible process (1740) resulted in the first reliable steel made by a melting process. Oven coke (about 1.5–4 in., or 40–100 mm, in size) is used in blast furnaces to make iron. Smaller quantities of coke are used in other metallurgical processes (see metallurgy), such as the manufacture of certain alloys. Large, strong coke, known as foundry coke, is used in smelting. Smaller sizes of coke (0.6–1.2 in., or 15–30 mm) are used to heat buildings.

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▪ coal product

      solid residue remaining after certain types of bituminous coals are heated to a high temperature out of contact with air until substantially all of the volatile constituents have been driven off. The residue is chiefly carbon, with minor amounts of hydrogen, nitrogen, sulfur, and oxygen. Also present in coke is the mineral matter in the original coal, chemically altered and decomposed during the coking process.

      Oven coke (size: 40 to 100 millimetres, about 1 ¹/₂ to 4 inches) is used throughout the world in blast furnaces to make iron. Smaller quantities of coke are used in other metallurgical processes, such as the manufacture of ferroalloys, lead, and zinc, and in kilns to make lime and magnesia. Large, strong coke, known as foundry coke, is used in foundry cupolas to smelt iron ores. Smaller sizes of both oven and gas coke (15 to 50 millimetres) are used to heat houses and commercial buildings. Coke measuring 10 to 25 millimetres in size is employed in the manufacture of phosphorus and of calcium carbide, the raw material from which acetylene is made. Coke breeze (less than 12 millimetres) is applied to the sintering of small iron ore prior to use in blast furnaces. Any surplus breeze coke becomes industrial boiler fuel.

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