Glossary

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Ash    Impurities (iron, alumina, silica) contained in coal
    
Basin    A depression in the Earth’s crust filled with sediment
    
Biomass    Living material which can be converted to energy
    
Bituminous    A rank of black coal of medium energy value.  It is used mainly for power generation, but is sometimes used for steel making.  

Bord and pillar    Underground mining method that leaves spaces (bords) and pillars (blocks of coal) supporting the roof
    
Blast furnace    A tall furnace in which coke reacts with iron ore to reduce it to pure iron
    
Btu    British thermal unit.  It is the amount of heat required to raise the temperature of 1 pound (453g) of water by 1°F (17°C)
    
Bulk commodities    Low value materials, such as iron ore and coal, which must be handled efficient in large quantities if a profit is to be made from their sale
 
Carbon dioxide    Colourless, odourless, non-toxic, radiative gas formed when carbon combines with oxygen – CO2.  A major greenhouse gas
    
Clean coal technologies    Technologies which improve the environmental performance of coal and other energy use through decreased emissions.
    
Coal    An organic sedimentary rock formed from partly decayed plant material which has been metamorphosed by heat and pressure of geologic time
    
Coalification    The process where heat and pressure turn decomposing plant material to coal
    
Coal preparation    The process to convert mined coal to provide a pure product.  This is done by washing out ash, either through crushing and sieving, electro-static treatment or via a liquid form.
    
Coal terminal    Stockpile of coal kept at a port
    
Colliery    An underground coal mine
    
Coke    A solid lump of almost pure carbon formed when coal is heated (at heats as high as 2000°F (1093°C) in the absence of air.  This de-volatilised coal is used as a reductant in the blast furnace.  It is derived from coking coal. Coke is hard, grey and porous, and is used in iron and steelmaking
    
Coking coal    Coal from which coke is produced (also known as metallurgical coal).  It is a low-ash, low-sulphur bituminous coal.
    
CV    Calorific value
    
Dragline    A large bucket excavator used in open-cut mines
    
Energy    The capacity to do work, also a term used for fuel sources used to provide power
    
Energy Mix    The combination of available fuel sources used to provide energy.  The ‘mix’ includes coal, gas, oil, water (hydro), uranium (nuclear), wind, sunlight (solar) and geothermal.
    
Generator    A machine which, when the magnet around its shaft is turned, generates electricity in the surrounding coils of wire
    
Glossopteris    An extinct seed-fern which made up most Permian coal deposits
    
Greenhouse gases    Gases which restrict the re-radiation of infrared heat in the atmosphere
    
Kinetic energy    Energy possessed by a moving or rotating object
    
Lignite    Lowest rank of coal, known as brown coal.  Moisture content c. 45%.  Heat content varies from 9 to 17 million Btu per ton (.907 tonne).  Used in power generation.
    
Liquefaction    The process of converting coal into a liquid fuel
    
Longwall mining    Mining technique where a mechanical shearer cuts along a coal face beneath a roof supported by hydraulic jacks
    
Metallurgical Coal    This is the coal used in metallurgical (steelmaking) processes.  The main metallurgical coals are coking coal and PCI (pulverisation coal injection) coals.
    
Methane    A gas comprising one atom of carbon bound to four hydrogen atoms – CH4.  A major greenhouse gas, it is the principal component of natural gas and is also a radiative gas.
    
Open-cut    A surface mining method where coal is exposed by removing the overlying rock
    
Outcrop    Rock or mineral material exposed on the Earth’s surface
    
Overburden    Waste rock material overlying a coal seam, also called spoil. It is removed and either dumped or used in reclaiming mined areas
    
Peat    Partially decomposed vegetation from marshes and swamps, it is dark brown or black in colour.  First stage of the coalification process.
    
Permian    A major coal forming geological period, about 250 million years ago
    
Radiative gases    These gases in the atmosphere allow the sun’s heat to pass through to Earth, but do not let the heat radiate from Earth and escape from the atmosphere.
    
Rank    A method of classifying coal based on the amounts of carbon and volatile matter it contains.  It signifies the coalification of the organic material
    
Rehabilitation    The process of returning a minded land surface into productive use
    
Run-of-mine (ROM)    Mined ore of a size that can be processed without the need for further crushing
    
Seam    Layer of coal – also called a bed
    
Sediment    Rock particles, such as sand and clay, produced by weathering
    
Shearer    A rotating cutting device used in underground coal mining
    
Steaming coal    All non-metallurgical coal
    
Sub-bituminous coal    This coal ranges from lignite to bituminous coal.  It is used primarily for power generation. It contains 20 – 30% moisture.  The heat content is 17 – 24 million Btu per ton (.907 tonne).
    
Thermal coal    Coal used in boilers for generating steam.  Also known as steaming coal.  This coal is used in power generation and as a fuel in cement kilns.
    
Topsoil    Surface layer of soil
    
Turbine    Machine in which blades are turned by gas or steam, usually connected to a generator
    
Volatile matter    Gas or vapour products, exclusive of water, given off by coal when it is heated to 9500°C
    

Sources:
ITAM
BARLOW JONKER COALPORTAL.COM
http://www.eia.doe.gov/cneaf/coal/page/gloss.html
http://www.coal.ca/class.htm

Photo by Robert Billington, courtesy of NSWMC