HeadframeA headframe (also known as a gallows frame, winding tower, hoist frame, pit frame, shafthead frame, headgear, headstock or poppethead) is the structural frame above an underground mine shaft so as to enable the hoisting of machinery, personnel, or materials. Modern headframes are built out of steel, concrete or a combination of both. Timber headframes are no longer used in industrialized countries, but are still used in developing nations.
Fossil fuel power stationA fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating gas engine. All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases.
OverburdenIn mining, overburden (also called waste or spoil) is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Overburden is distinct from tailings, the material that remains after economically valuable components have been extracted from the generally finely milled ore. Overburden is removed during surface mining, but is typically not contaminated with toxic components.
Child labourChild labour refers to the exploitation of children through any form of work that deprives them of their childhood, interferes with their ability to attend regular school, or is mentally, physically, socially and morally harmful. Such exploitation is prohibited by legislation worldwide, although these laws do not consider all work by children as child labour; exceptions include work by child artists, family duties, supervised training, and some forms of work undertaken by Amish children, as well as by indigenous children in the Americas.
SubsidenceSubsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement. Processes that lead to subsidence include dissolution of underlying carbonate rock by groundwater; gradual compaction of sediments; withdrawal of fluid lava from beneath a solidified crust of rock; mining; pumping of subsurface fluids, such as groundwater or petroleum; or warping of the Earth's crust by tectonic forces.
Gas ventingGas venting, more specifically known as natural-gas venting or methane venting, is the intentional and controlled release of gases containing alkane hydrocarbons - predominately methane - into earth's atmosphere. It is a widely used method for disposal of unwanted gases which are produced during the extraction of coal and crude oil. Such gases may lack value when they are not recyclable into the production process, have no export route to consumer markets, or are surplus to near-term demand.
Glossary of coal mining terminologyThis is a partial glossary of coal mining terminology commonly used in the coalfields of the United Kingdom. Some words were in use throughout the coalfields, some are historic and some are local to the different British coalfields. Adit An adit is an underground level or tunnel to the surface for access or drainage purposes. Afterdamp Afterdamp is a mixture of carbon monoxide and chokedamp which replaces atmospheric air after an explosion.
