67-521: The Auchincruive Waggonway or Whitletts Waggonway was a mineral railway or 'Bogey line' that transported mainly coal , eventually running from the north side of Ayr harbour at Newton to Blackhouse, Whitletts, Dalmilling, Gibbsyard, Auchincruive Holm, Annbank and Enterkine. Apart from carrying coal to the harbour, lime kilns, quarries and a salt works were also served. Writing in 1811 Aiton records that " Richard Oswald of Auchincruive, Esq; formed, some years ago, an iron rail-way, from his coal-works to near
134-512: A cyclothem . Cyclothems are thought to have their origin in glacial cycles that produced fluctuations in sea level , which alternately exposed and then flooded large areas of continental shelf. The woody tissue of plants is composed mainly of cellulose, hemicellulose, and lignin. Modern peat is mostly lignin, with a content of cellulose and hemicellulose ranging from 5% to 40%. Various other organic compounds, such as waxes and nitrogen- and sulfur-containing compounds, are also present. Lignin has
201-636: A 'main line' that ran from a complex of sidings running to the side of the quay at Newton on Ayr up through Wallacetown, onwards past Blackhouse, Whitletts and Dalmilling from whence it ran towards Thorneyflat with a branch to Gibbsyard, Stevenson and Wheatpark, whilst running onwards via New Barns to Holm where the terminus was for a number of years. Crossing the River Ayr below Oswald's Bridge it continued sometime after 1865 towards Annbank via Brockle Quarry and Colvinston Farm to end near Enterkine No. 3 Pit, at least five miles from Ayr. A number of other pits in
268-417: A process called carbonization . Carbonization proceeds primarily by dehydration , decarboxylation , and demethanation. Dehydration removes water molecules from the maturing coal via reactions such as Decarboxylation removes carbon dioxide from the maturing coal: while demethanation proceeds by reaction such as In these formulas, R represents the remainder of a cellulose or lignin molecule to which
335-540: A switch in fuels happened in London in the late sixteenth and early seventeenth centuries. Historian Ruth Goodman has traced the socioeconomic effects of that switch and its later spread throughout Britain and suggested that its importance in shaping the industrial adoption of coal has been previously underappreciated. The development of the Industrial Revolution led to the large-scale use of coal, as
402-403: A weight basis. This composition reflects partly the composition of the precursor plants. The second main fraction of coal is ash, an undesirable, noncombustable mixture of inorganic minerals. The composition of ash is often discussed in terms of oxides obtained after combustion in air: Of particular interest is the sulfur content of coal, which can vary from less than 1% to as much as 4%. Most of
469-406: A weight composition of about 54% carbon, 6% hydrogen, and 30% oxygen, while cellulose has a weight composition of about 44% carbon, 6% hydrogen, and 49% oxygen. Bituminous coal has a composition of about 84.4% carbon, 5.4% hydrogen, 6.7% oxygen, 1.7% nitrogen, and 1.8% sulfur, on a weight basis. The low oxygen content of coal shows that coalification removed most of the oxygen and much of the hydrogen
536-418: Is 40% of total fossil fuel emissions and over 25% of total global greenhouse gas emissions . As part of worldwide energy transition , many countries have reduced or eliminated their use of coal power . The United Nations Secretary General asked governments to stop building new coal plants by 2020. Global coal use was 8.3 billion tonnes in 2022, and is set to remain at record levels in 2023. To meet
603-636: Is also a cognate via the Indo-European root. The conversion of dead vegetation into coal is called coalification . At various times in the geologic past, the Earth had dense forests in low-lying areas. In these wetlands, the process of coalification began when dead plant matter was protected from oxidation , usually by mud or acidic water, and was converted into peat . The resulting peat bogs , which trapped immense amounts of carbon, were eventually deeply buried by sediments. Then, over millions of years,
670-429: Is burned in a turbine). Hot exhaust gases from the turbine are used to raise steam in a heat recovery steam generator which powers a supplemental steam turbine . The overall plant efficiency when used to provide combined heat and power can reach as much as 94%. IGCC power plants emit less local pollution than conventional pulverized coal-fueled plants. Other ways to use coal are as coal-water slurry fuel (CWS), which
737-411: Is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous ( Pennsylvanian ) and Permian times. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until
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#1732791933687804-603: Is entirely vertical; however, metamorphism may cause lateral changes of rank, irrespective of depth. For example, some of the coal seams of the Madrid, New Mexico coal field were partially converted to anthracite by contact metamorphism from an igneous sill while the remainder of the seams remained as bituminous coal. The earliest recognized use is from the Shenyang area of China where by 4000 BC Neolithic inhabitants had begun carving ornaments from black lignite. Coal from
871-455: Is made when metallurgical coal (also known as coking coal ) is baked in an oven without oxygen at temperatures as high as 1,000 °C, driving off the volatile constituents and fusing together the fixed carbon and residual ash. Metallurgical coke is used as a fuel and as a reducing agent in smelting iron ore in a blast furnace . The carbon monoxide produced by its combustion reduces hematite (an iron oxide ) to iron. Pig iron , which
938-409: Is more abundant, and anthracite. The % carbon in coal follows the order anthracite > bituminous > lignite > brown coal. The fuel value of coal varies in the same order. Some anthracite deposits contain pure carbon in the form of graphite . For bituminous coal, the elemental composition on a dry, ash-free basis of 84.4% carbon, 5.4% hydrogen, 6.7% oxygen, 1.7% nitrogen, and 1.8% sulfur, on
1005-526: Is too rich in dissolved carbon, is also produced. River Ayr The River Ayr (pronounced like air , Uisge Àir in Gaelic ) is a river in Ayrshire , Scotland . At 65 km (40 mi) it is the longest river in the county. The river was held as sacred by pre-Christian cultures. The remains of several prehistoric sacrificial horse burials have been found along its banks, mainly concentrated around
1072-447: Is unclear how many steam locomotives were used however one is described as being about 25 horsepower, requiring no tender as the water tank was positioned above the boiler and the coal was stored on either side of the driver's cab. The waggonway had a complex history with possible changes of route and frequent abandonment of branches and sidings as many of the pits had relatively short working lives. The waggonway at its greatest extent had
1139-452: Is used as fuel. 27.6% of world energy was supplied by coal in 2017 and Asia used almost three-quarters of it. Other large-scale applications also exist. The energy density of coal is roughly 24 megajoules per kilogram (approximately 6.7 kilowatt-hours per kg). For a coal power plant with a 40% efficiency, it takes an estimated 325 kg (717 lb) of coal to power a 100 W lightbulb for one year. In 2022, 68% of global coal use
1206-715: The Bronze Age (3000–2000 BC), where it formed part of funeral pyres . In Roman Britain , with the exception of two modern fields, "the Romans were exploiting coals in all the major coalfields in England and Wales by the end of the second century AD". Evidence of trade in coal, dated to about AD 200, has been found at the Roman settlement at Heronbridge , near Chester ; and in the Fenlands of East Anglia , where coal from
1273-521: The Fushun mine in northeastern China was used to smelt copper as early as 1000 BC. Marco Polo , the Italian who traveled to China in the 13th century, described coal as "black stones ... which burn like logs", and said coal was so plentiful, people could take three hot baths a week. In Europe, the earliest reference to the use of coal as fuel is from the geological treatise On Stones (Lap. 16) by
1340-571: The Industrial Revolution . With the invention of the steam engine , coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity . Some iron and steel -making and other industrial processes burn coal. The extraction and burning of coal damages the environment , causing premature death and illness, and it is the largest anthropogenic source of carbon dioxide contributing to climate change . Fourteen billion tonnes of carbon dioxide were emitted by burning coal in 2020, which
1407-607: The Midlands was transported via the Car Dyke for use in drying grain. Coal cinders have been found in the hearths of villas and Roman forts , particularly in Northumberland , dated to around AD 400. In the west of England, contemporary writers described the wonder of a permanent brazier of coal on the altar of Minerva at Aquae Sulis (modern day Bath ), although in fact easily accessible surface coal from what became
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#17327919336871474-545: The Paris Agreement target of keeping global warming below 2 °C (3.6 °F) coal use needs to halve from 2020 to 2030, and "phasing down" coal was agreed upon in the Glasgow Climate Pact . The largest consumer and importer of coal in 2020 was China , which accounts for almost half the world's annual coal production, followed by India with about a tenth. Indonesia and Australia export
1541-728: The Somerset coalfield was in common use in quite lowly dwellings locally. Evidence of coal's use for iron -working in the city during the Roman period has been found. In Eschweiler , Rhineland , deposits of bituminous coal were used by the Romans for the smelting of iron ore . No evidence exists of coal being of great importance in Britain before about AD 1000, the High Middle Ages . Coal came to be referred to as "seacoal" in
1608-491: The coal gap in the Permian–Triassic extinction event , where coal is rare. Favorable geography alone does not explain the extensive Carboniferous coal beds. Other factors contributing to rapid coal deposition were high oxygen levels, above 30%, that promoted intense wildfires and formation of charcoal that was all but indigestible by decomposing organisms; high carbon dioxide levels that promoted plant growth; and
1675-447: The steam engine took over from the water wheel . In 1700, five-sixths of the world's coal was mined in Britain. Britain would have run out of suitable sites for watermills by the 1830s if coal had not been available as a source of energy. In 1947 there were some 750,000 miners in Britain, but the last deep coal mine in the UK closed in 2015. A grade between bituminous coal and anthracite
1742-407: The 13th century; the wharf where the material arrived in London was known as Seacoal Lane, so identified in a charter of King Henry III granted in 1253. Initially, the name was given because much coal was found on the shore, having fallen from the exposed coal seams on cliffs above or washed out of underwater coal outcrops, but by the time of Henry VIII , it was understood to derive from the way it
1809-527: The 1840s Messrs. George Taylor and Company owned pits near the Old Bridge; the Allison Pit near Russell Street; Newton Head Pit near Tam's Brig; as well as Saltfield and Green Pits near Newton Lodge. Two pits that had closed by 1869 were Peelhill No. 1 just north of Oswald's Bridge and Peelhill No. 2 that lay between Mount Loudoun and Mount Stairs. The Holm Pit stood just downstream of Oswald's Bridge on
1876-487: The Auchincruive Waggonway however he never commented on them. Coal Coal is a combustible black or brownish-black sedimentary rock , formed as rock strata called coal seams . Coal is mostly carbon with variable amounts of other elements , chiefly hydrogen , sulfur , oxygen , and nitrogen . Coal is a type of fossil fuel , formed when dead plant matter decays into peat which
1943-596: The Carboniferous, and suggested that climatic and tectonic factors were a more plausible explanation, reconstruction of ancestral enzymes by phylogenetic analysis corroborated a hypothesis that lignin degrading enzymes appeared in fungi approximately 200 MYa. One likely tectonic factor was the Central Pangean Mountains , an enormous range running along the equator that reached its greatest elevation near this time. Climate modeling suggests that
2010-598: The Central Pangean Mountains contributed to the deposition of vast quantities of coal in the late Carboniferous. The mountains created an area of year-round heavy precipitation, with no dry season typical of a monsoon climate. This is necessary for the preservation of peat in coal swamps. Coal is known from Precambrian strata, which predate land plants. This coal is presumed to have originated from residues of algae. Sometimes coal seams (also known as coal beds) are interbedded with other sediments in
2077-577: The Greek scientist Theophrastus (c. 371–287 BC): Among the materials that are dug because they are useful, those known as anthrakes [coals] are made of earth, and, once set on fire, they burn like charcoal [anthrakes]. They are found in Liguria ;... and in Elis as one approaches Olympia by the mountain road; and they are used by those who work in metals. Outcrop coal was used in Britain during
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2144-459: The OS map with double tracks leading to each. A horse would usually haul between 5 and 7 coal waggons carrying 26 cwt each. The use of steam locomotives is recorded and by 1860 they were used with the record of a death caused by an accident involving a locomotive returning from Annbank in 1865. The Oswald's Bridge to Annbank sections of the line involved substantial earthworks to create the cuttings and
2211-520: The border with Lanarkshire . It winds its way through East and South Ayrshire to its mouth at the town of Ayr , where it empties into the Firth of Clyde . On its way, the river passes through the villages of Muirkirk , Sorn , Catrine , Failford , Stair and Annbank , as well as passing the location of (the now ruined) Ayr Castle . The largest settlements being Ayr , Cumnock , Catrine , Ochiltree , Muirkirk and Sorn. Major land uses within
2278-426: The catchment area are agriculture , forestry , mining , leisure and recreation and urban development. Principal tributaries include: Many practitioners of hillwalking and other related activities are probably aware that the river is pathed for upwards of 90% of its length. Due to disputes with estate owners and weather damage, the walk does temporarily abandon the river in a couple of locations. The path begins in
2345-415: The centre of the track wooden sleepers do as they run right across the centre of the trackbed. Five- or six-foot-long wood sleepers made from beech with areas for the chairs have been found as have both wood pegs and wrought iron spikes. The waggonway gauge is not known, however from relics such as wooden railway sleepers estimates suggest 3 ft 6in, 4 ft 2in or 4 ft 8.5in. It is possible that
2412-469: The embankments as well as the impressive Brockle Bridge that crossed the River Ayr below Tarholm, however it was only in use for around fifteen years from 1865 and was closed in the 1870s and lifted well before 1775. The waggons were tipped at the hurry on the harbour edge and one end opened allowing the coal to tumble into the hold of the collier in a process that took about a minute for each waggon. It
2479-430: The evolution of the first trees . But bacteria and fungi did not immediately evolve the ability to decompose lignin, so the wood did not fully decay but became buried under sediment, eventually turning into coal. About 300 million years ago, mushrooms and other fungi developed this ability, ending the main coal-formation period of earth's history. Although some authors pointed at some evidence of lignin degradation during
2546-519: The factors involved in coalification, temperature is much more important than either pressure or time of burial. Subbituminous coal can form at temperatures as low as 35 to 80 °C (95 to 176 °F) while anthracite requires a temperature of at least 180 to 245 °C (356 to 473 °F). Although coal is known from most geologic periods , 90% of all coal beds were deposited in the Carboniferous and Permian periods. Paradoxically, this
2613-498: The form of iron pyrite (FeS 2 ). Being a dense mineral, it can be removed from coal by mechanical means, e.g. by froth flotation . Some sulfate occurs in coal, especially weathered samples. It is not volatilized and can be removed by washing. Minor components include: As minerals, Hg, As, and Se are not problematic to the environment, especially since they are only trace components. They become however mobile (volatile or water-soluble) when these minerals are combusted. Most coal
2680-462: The gauge was changed at some point during its long history. Most of the route was single track with numerous passing loops. No indication of formal signalling is recorded. It is not clear what sort of rails were used in the early days as sand would have accumulated on L-shaped rails; however, waggons without a flange may have been used. A wrought iron rail and a section of L-shaped cast iron rail have been recorded. In keeping with other such waggonways
2747-475: The heat and pressure of deep burial caused the loss of water, methane and carbon dioxide and increased the proportion of carbon. The grade of coal produced depended on the maximum pressure and temperature reached, with lignite (also called "brown coal") produced under relatively mild conditions, and sub-bituminous coal , bituminous coal , or anthracite coal (also called "hard coal" or "black coal") produced in turn with increasing temperature and pressure. Of
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2814-431: The increasing tendency of the anthracite to break with a conchoidal fracture , similar to the way thick glass breaks. As geological processes apply pressure to dead biotic material over time, under suitable conditions, its metamorphic grade or rank increases successively into: There are several international standards for coal. The classification of coal is generally based on the content of volatiles . However
2881-507: The line was probably worked by a combination of gravity, manually, by horses and eventually steam locomotives. Most of the coal carried to the North Quay from the pits at Whitletts and Auchincruive was transported in trains of four, two or three ton waggons hauled by horses. At the quay stood the wooden 'hurries' where the coal was tipped into the holds of the fleet of colliers and most transported to Ireland. In 1857 four hurries are shown on
2948-453: The morphology and some properties of the original plant. In many coals, individual macerals can be identified visually. Some macerals include: In coalification huminite is replaced by vitreous (shiny) vitrinite . Maturation of bituminous coal is characterized by bitumenization , in which part of the coal is converted to bitumen , a hydrocarbon-rich gel. Maturation to anthracite is characterized by debitumenization (from demethanation) and
3015-405: The most important distinction is between thermal coal (also known as steam coal), which is burnt to generate electricity via steam; and metallurgical coal (also known as coking coal), which is burnt at high temperature to make steel . Hilt's law is a geological observation that (within a small area) the deeper the coal is found, the higher its rank (or grade). It applies if the thermal gradient
3082-517: The most, followed by Russia . The word originally took the form col in Old English , from reconstructed Proto-Germanic * kula ( n ), from Proto-Indo-European root * g ( e ) u-lo- "live coal". Germanic cognates include the Old Frisian kole , Middle Dutch cole , Dutch kool , Old High German chol , German Kohle and Old Norse kol . Irish gual
3149-407: The nature of Carboniferous forests, which included lycophyte trees whose determinate growth meant that carbon was not tied up in heartwood of living trees for long periods. One theory suggested that about 360 million years ago, some plants evolved the ability to produce lignin , a complex polymer that made their cellulose stems much harder and more woody. The ability to produce lignin led to
3216-455: The number of double bonds between carbon). As carbonization proceeds, aliphatic compounds convert to aromatic compounds . Similarly, aromatic rings fuse into polyaromatic compounds (linked rings of carbon atoms). The structure increasingly resembles graphene , the structural element of graphite. Chemical changes are accompanied by physical changes, such as decrease in average pore size. The macerals are coalified plant parts that retain
3283-531: The old trackbed near the site of Annbaank House is used as a footpath and is known locally as the old line . Other contemporary waggonways existed on the Craigie and on the Holmiston estates with sections of trackbed traceable near the Holmiston lime kiln above Wallace's Heel Well . A very short waggonway appears to have existed at Wallacetown as far back as 1775. Robert Burns would have been familiar with
3350-456: The pre-combustion treatment, turbine technology (e.g. supercritical steam generator ) and the age of the plant. A few integrated gasification combined cycle (IGCC) power plants have been built, which burn coal more efficiently. Instead of pulverizing the coal and burning it directly as fuel in the steam-generating boiler, the coal is gasified to create syngas , which is burned in a gas turbine to produce electricity (just like natural gas
3417-427: The reacting groups are attached. Dehydration and decarboxylation take place early in coalification, while demethanation begins only after the coal has already reached bituminous rank. The effect of decarboxylation is to reduce the percentage of oxygen, while demethanation reduces the percentage of hydrogen. Dehydration does both, and (together with demethanation) reduces the saturation of the carbon backbone (increasing
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#17327919336873484-467: The remains of waggonway bridges across the River Ayr at Brockle Quarry and below Oswald's Bridge. Road overbridges survive intact at Oaklea Farm and Colvinston Farm. Stone railway sleepers with the imprint of the chair base and two drilled holes survive as part of the Oaklea Bridge. Foundations of buildings and the abutment of the old bridge survive in the vicinity of the old Holm Pit. A section of
3551-429: The south side of the river and operated in the 1860s. By 1839 nearly 70,000 tons of coal per year were being carried by the waggonway and exported by ship. The Kerr Pit near Whitletts had closed by 1854, Blackhouse Pit closed in 1863 and Auchincruive Pits by the late 1860s. It is known that various sorts of sleepers were used, including stone blocks that were favoured on horse-worked lines, as they did not interfere with
3618-399: The sulfur and most of the nitrogen is incorporated into the organic fraction in the form of organosulfur compounds and organonitrogen compounds . This sulfur and nitrogen are strongly bound within the hydrocarbon matrix. These elements are released as SO 2 and NO x upon combustion. They cannot be removed, economically at least, otherwise. Some coals contain inorganic sulfur, mainly in
3685-471: The town of Ayr , but could not obtain liberty to carry it through the Burgh-acres, to the harbour. " Aiton also notes that " Taylor Esq; has made a rail-way, of nearly the same length, from his coal-pits, in the lands of Newton, to the north harbour of Ayr. " By 1792 the waggonway had reached Ayr harbour and a report of 1807 indicates that the old waggonway had been completely replaced. The waggonway
3752-628: The town of Ayr . The name Ayr may come from a pre-Celtic word meaning "watercourse". Ayr could also be of Brittonic derivation, perhaps from the element *ar , an ancient river-name element implying horizontal movement. The town of Ayr was formerly known as Inver Ayr meaning "mouth of the Ayr" (see Inver ), but this was later shortened to just Ayr . The River Ayr has a catchment area of 574 km (222 sq mi). The river originates at Glenbuck Loch in East Ayrshire , close to
3819-593: The vicinity of the waggonway may also have been served by the waggonway although no hard evidence survives. A large embankment ran across the Long Holm to the Holm Pit at Oswald's Bridge and this was removed the 1920s although it is till visible as a cropmark . Little or nothing survives at many of the various pits and associated spoil heaps, however sections of the track bed can be identified in such places as Cutting Wood and Pheasant Nook near Auchincruive as well as
3886-415: The world's coal-generated electricity. Efforts around the world to reduce the use of coal have led some regions to switch to natural gas and renewable energy . In 2018 coal-fired power station capacity factor averaged 51%, that is they operated for about half their available operating hours. Coke is a solid carbonaceous residue that is used in manufacturing steel and other iron-containing products. Coke
3953-574: Was based on the trading of this commodity. Coal continues to arrive on beaches around the world from both natural erosion of exposed coal seams and windswept spills from cargo ships. Many homes in such areas gather this coal as a significant, and sometimes primary, source of home heating fuel. Coal consists mainly of a black mixture of diverse organic compounds and polymers. Of course, several kinds of coals exist, with variable dark colors and variable compositions. Young coals (brown coal, lignite) are not black. The two main black coals are bituminous, which
4020-510: Was carried to London by sea. In 1257–1259, coal from Newcastle upon Tyne was shipped to London for the smiths and lime -burners building Westminster Abbey . Seacoal Lane and Newcastle Lane, where coal was unloaded at wharves along the River Fleet , still exist. These easily accessible sources had largely become exhausted (or could not meet the growing demand) by the 13th century, when underground extraction by shaft mining or adits
4087-612: Was developed in the Soviet Union , or in an MHD topping cycle . However these are not widely used due to lack of profit. In 2017 38% of the world's electricity came from coal, the same percentage as 30 years previously. In 2018 global installed capacity was 2 TW (of which 1TW is in China) which was 30% of total electricity generation capacity. The most dependent major country is South Africa, with over 80% of its electricity generated by coal; but China alone generates more than half of
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#17327919336874154-408: Was developed. The alternative name was "pitcoal", because it came from mines. Cooking and home heating with coal (in addition to firewood or instead of it) has been done in various times and places throughout human history, especially in times and places where ground-surface coal was available and firewood was scarce, but a widespread reliance on coal for home hearths probably never existed until such
4221-497: Was during the Late Paleozoic icehouse , a time of global glaciation . However, the drop in global sea level accompanying the glaciation exposed continental shelves that had previously been submerged, and to these were added wide river deltas produced by increased erosion due to the drop in base level . These widespread areas of wetlands provided ideal conditions for coal formation. The rapid formation of coal ended with
4288-627: Was once known as "steam coal" as it was widely used as a fuel for steam locomotives . In this specialized use, it is sometimes known as "sea coal" in the United States. Small "steam coal", also called dry small steam nuts (DSSN), was used as a fuel for domestic water heating . Coal played an important role in industry in the 19th and 20th century. The predecessor of the European Union , the European Coal and Steel Community ,
4355-509: Was still in active use in 1838 when the Glasgow, Paisley, Kilmarnock and Ayr Railway was constructed with its terminus north of the river in Newton and this necessitated the construction of a level manned crossing with gates. The act authorising the construction of the line included an amendment that prevented the company from interfering with the waggonway's operation. The GPK&AR's successor
4422-530: Was the Glasgow & South Western Railway and they also were prevented from disrupting the smooth running of the waggonway when they extend their line south of the river. By 1837 the waggonway had been extended to Whitletts and by 1838 it had extended to Dalmilling, reaching the Thorneyflat area after 1838 and the Auchincruive pits by 1846. Annbank was in use by the 1860s and had closed by 1872. In
4489-430: Was used for electricity generation. Coal burnt in coal power stations to generate electricity is called thermal coal . It is usually pulverized and then burned in a furnace with a boiler . The furnace heat converts boiler water to steam , which is then used to spin turbines which turn generators and create electricity. The thermodynamic efficiency of this process varies between about 25% and 50% depending on
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