85-591: 56°07′19″N 3°46′30″W / 56.122°N 3.775°W / 56.122; -3.775 The Upper Hirst is a coal seam in central Scotland that was mined on a large scale in the 1950s through to 2002, mainly to supply Kincardine Power Station , and later, Longannet Power Station , in Fife . This was a low-quality coal, unsuitable for most other purposes, and had mostly been disregarded previously. Its low sulfur content made it very suitable for power station use. It burns relatively slowly making it popular in
170-683: A coal preparation plant . Technical and economic feasibility are evaluated based on the following: regional geological conditions; overburden characteristics; coal seam continuity, thickness, structure, quality, and depth; strength of materials above and below the seam for roof and floor conditions; topography, especially altitude and slope; climate; land ownership as it affects the availability of land for mining and access; surface drainage patterns; groundwater conditions; availability of labor and materials; coal purchaser requirements in terms of tonnage, quality, and destination; and capital investment requirements. Surface mining and deep underground mining are
255-705: A 70% increase over the 20 years since 1999. In 2018, the world production of brown coal (lignite) was 803.2 Mt, with Germany the world's largest producer at 166.3 Mt. China is most likely the second largest producer and consumer of lignite globally although specific lignite production data is not made available. Coal production has grown fastest in Asia, while Europe has declined. Since 2011, world coal production has been stable, with decreases in Europe and US offset by increases from China, Indonesia and Australia. The top coal mining nations are: Energy production from coal mining
340-467: A coal seam occurring near the top of a ridge or hill, the entire top is removed in a series of parallel cuts. Overburden is deposited in nearby valleys and hollows. This method usually leaves the ridge and hilltops as flattened plateaus. The process is highly controversial for the drastic changes in topography, the practice of creating head-of-hollow-fills , or filling in valleys with mining debris, and for covering streams and disrupting ecosystems. Spoil
425-413: A controlled explosion. On 9 December 2021, the chimney stack was demolished. The station was designed by Scottish architects Robert Matthew, Johnson Marshall & Partners . Consulting Engineers were Merz and McLellan . Construction began in 1964, 4 km (2.5 mi) downstream of the existing Kincardine power station . The station was constructed on 30 hectares (74 acres) of land reclaimed from
510-403: A greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited. This equipment can include the following: Draglines which operate by removing the overburden, power shovels, large trucks in which transport overburden and coal, bucket wheel excavators, and conveyors. In this mining method, explosives are first used in order to break through
595-481: A higher amount of energy per unit mass, specific energy or massic energy, and can often be obtained in areas where wood is not readily available. Though it was used historically as a domestic fuel, coal is now used mostly in industry, especially in smelting and alloy production, as well as electricity generation . Large-scale coal mining developed during the Industrial Revolution , and coal provided
680-440: A land use condition is not equal to the original use. Existing land uses (such as livestock grazing, crop and timber production) are temporarily eliminated in mining areas. High-value, intensive-land-use areas like urban and transportation systems are not usually affected by mining operations. If mineral values are sufficient, these improvements may be removed to an adjacent area. Strip mining eliminates existing vegetation, destroys
765-440: A large dining-room table, but with hydraulic jacks for legs. After the large pillars of coal have been mined away, the mobile roof support's legs shorten and it is withdrawn to a safe area. The mine roof typically collapses once the mobile roof supports leave an area. There are six principal methods of underground mining: Coal is mined commercially in over 50 countries. 7,921 million metric tons (Mt) of coal were produced in 2019,
850-447: A method that currently accounts for about 60 percent of world coal production. In deep mining, the room and pillar or bord and pillar method progresses along the seam, while pillars and timber are left standing to support the mine roof. Once room and pillar mines have been developed to a stopping point limited by geology, ventilation, or economics, a supplementary version of room and pillar mining, termed second mining or retreat mining ,
935-524: A new coal mine. Longannet Power Station Longannet power station / l ɒ ŋ ˈ æ n ɪ t / was a large coal-fired power station in Fife , and the last coal-fired power station in Scotland. It was capable of co-firing biomass , natural gas and sludge . The station stood on the north bank of the Firth of Forth , near Kincardine on Forth . Its generating capacity of 2,400 megawatts
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#17327839647281020-425: A pressure of 168 bars (16,800 kPa) and a temperature of 568 °C (1,054 °F) to two 300 MW General Electric Company turbo generators . The thermal efficiency of the plant was around 37%. Coal was originally supplied directly by conveyor belt from the neighbouring Longannet Colliery , until it closed in 2002 after a flood. Around half of the coal used was Scottish, and the rest had to be imported,
1105-589: A result of occupational exposures is coined occupational hearing loss . To protect miners' hearing, the US Mine Safety and Health Administration 's (MSHA) guidelines for noise place a Permissible Exposure Limit (PEL) for noise at 90 dBA time-weighted over 8 hours. A lower cutoff, 85 dBA, is set for a worker to fall into the MSHA Action Level which dictates that workers be placed into hearing conservation programs. Noise exposures vary depending on
1190-547: A similar calorific value to low-quality brown coal . In 2005, a judge ruled the burning of sludge as illegal, but the SEPA continued to allow Scottish Power to burn the sludge illegally as part of an agreement which originally required Scottish Power to construct, and have in operation, a biomass plant in 2010. All burning of biomass at Longannet – including waste-derived fuel and sawdust pellets – ceased in April 2012. In 2007,
1275-545: A slogan onto the chimney that read "Make Coal History". The explosives were triggered by the First Minister of Scotland , Nicola Sturgeon . Longannet had an installed capacity of 2,400 MW and a declared net capacity of 2,304 MW due to plant overheads. The station produced 9,525 GWh of electricity in 2012, an increase on the 9,139 GWh produced in 2011. The station consumed up to 4,500,000 tonnes (4,400,000 long tons; 5,000,000 short tons) of coal each year. Coal
1360-485: A surface (also called an open cast) mine. Additionally, coal seam thickness and geology are factors in the selection of a mining method. The most economical method of coal extraction for surface mines is the electric shovel or drag line. The most economical form of underground mining is the long wall, which involves using two spinning drums with carbide bits that runs along sections of the coal seam. Many coals extracted from both surface and underground mines require washing in
1445-575: Is accomplished by drilling holes into the overburden, filling the holes with explosives, and detonating the explosive. The overburden is then removed, using large earth-moving equipment, such as draglines , shovel and trucks, excavator and trucks, or bucket-wheels and conveyors. This overburden is put into the previously mined (and now empty) strip. When all the overburden is removed, the underlying coal seam will be exposed (a 'block' of coal). This block of coal may be drilled and blasted (if hard) or otherwise loaded onto trucks or conveyors for transport to
1530-427: Is commonly started. Miners remove the coal in the pillars, thereby recovering as much coal from the coal seam as possible. A work area involved in pillar extraction is called a pillar section. Modern pillar sections use remote-controlled equipment, including large hydraulic mobile roof-supports, which can prevent cave-ins until the miners and their equipment have left a work area. The mobile roof supports are similar to
1615-418: Is dedicated to mining activities until it can be reshaped and reclaimed. If mining is allowed, resident human populations must be resettled off the mine site; economic activities, such as agriculture or hunting and gathering food and medicinal plants are interrupted. What becomes of the land surface after mining is determined by the manner in which the mining is conducted. Usually reclamation of disturbed lands to
1700-516: Is highly concentrated in certain jurisdictions, which also concentrates much of the social and economic impacts of the industry to these regions. The industry directly employs over seven million workers worldwide, which, in turn, creates millions of indirect jobs. In several parts of the world, producers have reached peak coal as some economies shift away from fossil fuels to address climate change. A 2020 study found that renewables jobs could feasibly be created in these geographies to replace many of
1785-484: Is mostly used to generate electricity, and 75% of annual coal production is exported, mostly to eastern Asia. In 2007, 428 million tonnes of coal was mined in Australia. In 2007, coal provided about 85% of Australia's electricity production. In the fiscal year 2008/09, 487 million tonnes of coal was mined, and 261 million tonnes was exported. In the fiscal year 2013/14, 430.9 million tonnes of coal
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#17327839647281870-417: Is partially economically recoverable. Coal refuse is distinct from the byproducts of burning coal, such as fly ash . Piles of coal refuse can have significant negative environmental consequences, including the leaching of iron, manganese, and aluminum residues into waterways and acid mine drainage . The runoff can create both surface and groundwater contamination. The piles also create a fire hazard, with
1955-593: Is placed at the head of a narrow, steep-sided valley or hollow. In preparation for filling this area, vegetation and soil are removed and a rock drain constructed down the middle of the area to be filled, where a natural drainage course previously existed. When the fill is completed, this underdrain will form a continuous water runoff system from the upper end of the valley to the lower end of the fill. Typical head-of-hollow fills are graded and terraced to create permanently stable slopes. Most coal seams are too deep underground for opencast mining and require underground mining,
2040-399: Is probably much less than the redundancy payments to the approximately 200 staff when the company went into receivership in indecent haste. The investigation by HM Inspectorate of Mines is thorough and meticulous, but does not conceal the fact that nothing has been proved about what really happened underground. Meanwhile, many tens of millions of tons of Upper Hirst coal remain inaccessible,
2125-436: Is referred to as 'overburden' and is removed in long strips. The overburden from the first strip is deposited in an area outside the planned mining area and referred to as out-of-pit dumping. Overburden from subsequent strips is deposited in the void left from mining the coal and overburden from the previous strip. This is referred to as in-pit dumping. It is often necessary to fragment the overburden by use of explosives. This
2210-515: Is removed and overburden dumped to the side. Dust, vibration, and diesel exhaust odors are created (affecting sight, sound, and smell). Residents of local communities often find such impacts disturbing or unpleasant. In case of mountaintop removal , tops are removed from mountains or hills to expose thick coal seams underneath. The soil and rock removed is deposited in nearby valleys, hollows and depressions, resulting in blocked (and contaminated) waterways. Removal of soil and rock overburden covering
2295-712: Is still common, with 4,000 new cases of black lung every year in the US (4 percent of workers annually) and 10,000 new cases every year in China (0.2 percent of workers). The use of water sprays in mining equipment reduces the risk to miners' lungs. Build-ups of a hazardous gas are known as damps, possibly from the German word Dampf which means steam or vapor: Noise is also a contributing factor to potential adverse effects on coal miners' health. Exposure to excessive noise can lead to noise-induced hearing loss . Hearing loss developed as
2380-523: Is thought the Valleyfield Moat Pit. Their activities ceased in 1676 with the exhaustion of easily accessible reserves. Coal seam Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production. In
2465-435: Is used for both thermal and metallurgical coals . In New South Wales open casting for steam coal and anthracite is practiced. Surface mining accounts for around 80 percent of production in Australia, while in the US it is used for about 67 percent of production. Globally, about 40 percent of coal production involves surface mining. Strip mining exposes coal by removing earth above each coal seam. This earth to be removed
2550-544: The United Kingdom and South Africa , a coal mine and its structures are a colliery , a coal mine is called a "pit", and above-ground mining structures are referred to as a " pit head ". In Australia , "colliery" generally refers to an underground coal mine. Coal mining has had many developments in recent years, from the early days of men tunneling, digging, and manually extracting the coal on carts to large open-cut and longwall mines. Mining at this scale requires
2635-503: The global energy economy . The major coal producing countries, though, such as China , Indonesia, India and Australia , have not reached peak production, with production increases replacing falls in Europe and the United States and proposed mines under development. The coal mining industry employs almost 2.7 million workers. The History of coal mining goes back thousands of years, with early mines documented in ancient China,
Upper Hirst - Misplaced Pages Continue
2720-812: The 16th century for the manufacture of salt and glass. The seam is also known locally as the Jenny Pate or the Janet Peat. The Upper Hirst coal is found within the Upper Limestone Group of strata, above the Limestone Coal Group, but below the Productive Coal Measures. The latter two groups of strata may be separated by up to 1,000 metres. In the Central Coal Field, which is in the form of a basin,
2805-400: The 1860s onward. By the late 20th century, coal was, for the most part, replaced in domestic as well as industrial and transportation usage by oil , natural gas or electricity produced from oil, gas, nuclear power or renewable energy sources. By 2010, coal produced over a fourth of the world's energy. Coal extraction methods vary depending on whether the mine is an underground mine or
2890-590: The EU Industrial Emissions Directive . The station closed on 24 March 2016. Demolition at the site commenced in November 2018 with the 'blow down' of the coal stock towers. The eastern boiler annexe was demolished on 11 April 2019. The boiler house, turbine hall and control room were all demolished on 4 February 2021. On 9 December 2021, the chimney stack was demolished. Three days before this, Scottish Power had illuminated
2975-612: The Firth of Forth using ash from the Kincardine station. It began generating electricity in 1970, with a design lifetime of 30 years, and was in full operation by 1973. At the time of its completion, the station was the largest in Europe. The facility was operated by the South of Scotland Electricity Board until 1990 when the electricity industry in the UK was privatised . After that it
3060-449: The Productive Coal Measures, if they were ever deposited, have been lost by erosion except near the centre, where they outcrop near Alloa and Clackmannan , and have been mined until recently. The Limestone Coal Group of strata have been mined only around the edge of the basin, although in the 1950s there were plans for deep mines at Airth , where two large shafts were constructed to rockhead and then abandoned, and at Gartarry Toll , which
3145-579: The Roman Empire and other early historical economies. It became important in the Industrial Revolution of the 19th and 20th centuries, when it was primarily used to power steam engines, heat buildings and generate electricity. Coal mining continues as an important economic activity today, but has begun to decline due to the strong contribution coal plays in global warming and environmental issues, which result in decreasing demand and in some geographies, peak coal . Compared to wood fuels , coal yields
3230-812: The U.S., Examples include the Sago Mine disaster of 2006, and the 2007 mine accident in Utah 's Crandall Canyon Mine , where nine miners were killed and six entombed. In the decade 2005–2014, US coal mining fatalities averaged 28 per year. The most fatalities during the 2005–2014 decade were 48 in 2010, the year of the Upper Big Branch Mine disaster in West Virginia, which killed 29 miners. Chronic lung diseases, such as pneumoconiosis (black lung) were once common in miners, leading to reduced life expectancy . In some mining countries black lung
3315-624: The US Department of Labor's Mine Safety and Health Administration (MSHA) show that between 1990 and 2004, the industry cut the rate of injuries by more than half and fatalities by two-thirds. But according to the Bureau of Labor Statistics , even in 2006, mining remained the second most dangerous occupation in America, when measured by fatality rate . These numbers, however, include all mining activities, and oil and gas mining contribute to
3400-499: The Upper Hirst coal, and brought deep mining in Scotland to an end. The source of the flooding was allegedly the failure of a dam constructed to keep water which accumulated in the old workings to the north out of the working part of the mine, but there are substantial gaps in the known facts. A local mine manager claimed that the water, about 20 million gallons (a small amount in mining terms) could be pumped out for £55,000, which
3485-565: The allowed level of particulate emissions. This was beneficial as SO 3 is hazardous. In 1994, the station was awarded funding from the European Commission under the THERMIE Demonstration Programme. With this money, Unit 2 at the station was retrofitted with gas-reburn equipment. This was the largest scale application of this technology in the world. In this process, natural gas is injected into
Upper Hirst - Misplaced Pages Continue
3570-472: The artificial island. But in a great storm on 30 March 1625, coinciding with high tide, the colliery, the first under sea mine in the world, was flooded. Sir George Bruce died later that year, and only some very limited working at the Moat Pit ever took place again. Instead his sons concentrated their mining to the east of Culross where 8-9 further shafts were sunk including 2 more moated pits, St Mungo's and it
3655-451: The boiler. This cut NOx emissions from Unit 2 by 50%, as well as giving a reduction in CO 2 and SO 2 emissions. In 1996, all the station's boilers were fitted with Low NOx burners . This reduced the station's NOx emissions by 40%. The blend of coal fed to each unit was intended to minimise emissions of sulphur. The UK's first carbon capture and storage (CCS) unit was commissioned at
3740-613: The coal all emerging at Longannet, except that from Dollar, which due to faulting could not be economically linked to the main conveyor system. This scheme was a great success, although the focus of mining shifted to the south as the Dollar basin was exhausted. Eventually coal was being extracted from south of the River Forth , and there were adequate reserves to last for at least the predicted lifetime of Longannet Power Station . A disastrous flood on 23 March 2002 terminated production of
3825-405: The coal at Dollar, Castlehill and Solsgirth, and bring the coal from Solsgirth, Bogside and Castlehill to the surface by conveyor at Longannet, immediately adjacent to the power station. Bogside, on the eastern extremity of the basin, could access the coal at no great depth, and it was worked down the dip to the west, via a large, deep shaft at Castlehill, which was latterly used for personnel access,
3910-581: The coal mining jobs as part of a just transition ; however, renewable energy was not suitable in some of the geographies with high concentrations of miners, such as in China, which is far and away the leading coal-mining nation. Coal refuse (also described as coal waste, rock, slag, coal tailings, waste material, rock bank, culm, boney, or gob ) is the material left over from coal mining, usually as tailings piles or spoil tips . For every tonne of hard coal generated by mining, 400 kg (880 lb) of waste material remains, which includes some lost coal that
3995-497: The coal preparation (or wash) plant. Once this strip is empty of coal, the process is repeated with a new strip being created next to it. This method is most suitable for areas with flat terrain. Equipment to be used depends on geological conditions. For example, to remove overburden that is loose or unconsolidated, a bucket wheel excavator might be the most productive. The life of some area mines may be more than 50 years. The contour mining method consists of removing overburden from
4080-863: The coal resource may cause burial and loss of topsoil, exposes parent material, and creates large infertile wastelands. Soil disturbance and associated compaction result in conditions conducive to erosion. Soil removal from the area to be surface-mined alters or destroys many natural soil characteristics, and reduces its biodiversity and productivity for agriculture. Soil structure may be disturbed by pulverization or aggregate breakdown. Top 10 hard and brown coal producers in 2012 were (in million metric tons): China 3,621, United States 922, India 629, Australia 432, Indonesia 410, Russia 351, South Africa 261, Germany 196, Poland 144, and Kazakhstan 122. Coal has been mined in every state of Australia, but mainly in Queensland, New South Wales and Victoria. It
4165-429: The developed world. Modern coal mining in the US has an average 23 deaths per year due to mine accidents (2001–2020). However, in lesser developed countries and some developing countries, many miners continue to die annually, either through direct accidents in coal mines or through adverse health consequences from working under poor conditions. China , in particular, has the highest number of coal mining related deaths in
4250-458: The dip of the basin, to the east. The Upper Hirst was initially mined experimentally at the site of Bannockburn colliery by a small drift mine, then at mid-shaft in Polmaise 3/4 (commonly called Fallin ), Manor Powis, and later the drift mines at Dollar and Bogside, to supply Kincardine Power Station , but when Longannet Power Station was built, an innovative scheme was developed to mine
4335-455: The disruptive activities of blasting, ripping, and excavating coal. Stripping of overburden eliminates and destroys archeological and historic features, unless they are removed beforehand. The removal of vegetative cover and activities associated with the construction of haul roads, stockpiling of topsoil, displacement of overburden and hauling of soil and coal increase the quantity of dust around mining operations. Dust degrades air quality in
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#17327839647284420-571: The fatalities occurring in the first half of the 20th century. 3,242 died in 1907, the worst year ever; in 2020 there were five. Open cut hazards are principally mine wall failures and vehicle collisions; underground mining hazards include suffocation, gas poisoning, roof collapse, rock burst , outbursts , and gas explosions. Firedamp explosions can trigger the far more dangerous coal dust explosions, which can engulf an entire mine. Most of these risks are greatly reduced in modern mines, and multiple fatality incidents are now rare in most parts of
4505-457: The genetic soil profile, displaces or destroys wildlife and habitat, alters current land uses, and to some extent permanently changes the general topography of the area mined. Adverse impacts on geological features of human interest may occur in a coal strip mine. Geomorphic and geophysical features and outstanding scenic resources may be sacrificed by indiscriminate mining. Paleontological, cultural, and other historic values may be endangered due to
4590-450: The immediate area, has an adverse impact on vegetative life, and constitutes health and safety hazards for mine workers and nearby residents. Surface mining disrupts virtually all aesthetic elements of the landscape. Alteration of land forms often imposes unfamiliar and discontinuous configurations. New linear patterns appear as material is extracted and waste piles are developed. Different colors and textures are exposed as vegetative cover
4675-552: The main source of primary energy for industry and transportation in industrial areas from the 18th century to the 1950s. Coal remains an important energy source. Coal is also mined today on a large scale by open pit methods wherever the coal strata strike the surface or are relatively shallow. Britain developed the main techniques of underground coal mining from the late 18th century onward, with further progress being driven by 19th-century and early 20th-century progress. However, oil and gas were increasingly used as alternatives from
4760-404: The majority of fatalities. Coal mining resulted in 47 fatalities that year. One study, though, has suggested that hazards of modern mining are now more accretive with workers facing long-term health impacts, such as sleep deprivation, that build up over time. Strip mining severely alters the landscape, which reduces the value of the natural environment in the surrounding land. The land surface
4845-613: The majority via the former British Steel plc ore loading facility at Hunterston Terminal in Ayrshire . Onward transport was by rail and the level of traffic required to supply Longannet's fuel demand caused congestion on the Scottish rail network. An alternative route, the Stirling-Alloa-Kincardine rail link , at the mouth of the river Forth was reopened in 2008, and was also used to deliver coal. The chimney
4930-461: The method of extraction. For example, a study has found that among surface coal mine operations, dragline equipment produced the loudest sound at a range of 88–112 dBA. Within longwall sections, stageloaders used to transport coal from the mining face and shearers used for extraction represent some of the highest noise exposures. Auxiliary fans (up to 120 dBA), continuous mining machines (up to 109 dBA), and roof bolters (up to 103 dBA) represent some of
5015-465: The mining workforce. in 2015 US coal mines had 65,971 employees, the lowest figure since EIA began collecting data in 1978. However, a 2016 study reported that a relatively minor investment would allow most coal workers to retrain for the solar energy industry. Coal mining has been a very dangerous activity and the list of historical coal mining disasters is long. In the U.S., 104,895 coal miners were killed in mine accidents since 1900, 90 percent of
5100-469: The noisiest equipment within continuous mining sections. Exposures to noise exceeding 90 dBA can lead to adverse effects on workers' hearing. The use of administrative controls and engineering controls can be used to reduce noise exposures. Improvements in mining methods (e.g. longwall mining), hazardous gas monitoring (such as safety-lamps or more modern electronic gas monitors), gas drainage, electrical equipment , and ventilation have reduced many of
5185-590: The open pit methods, due to thickness of the seam 20–25 metres (60–90 feet). Coals occurring below 90 m (300 ft) are usually deep mined. However, there are open pit mining operations working on coal seams up to 300–460 metres (1,000–1,500 feet) below ground level, for instance Tagebau Hambach in Germany. When coal seams are near the surface, it may be economical to extract the coal using open-cut , also referred to as open-cast, open-pit, mountaintop removal or strip, mining methods. Opencast coal mining recovers
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#17327839647285270-421: The operation reaches a predetermined stripping ratio (tons of overburden/tons of coal), it is not profitable to continue. Depending on the equipment available, it may not be technically feasible to exceed a certain height of highwall. At this point, it is possible to produce more coal with the augering method in which spiral drills bore tunnels into a highwall laterally from the bench to extract coal without removing
5355-408: The overburden. Mountaintop coal mining is a surface mining practice involving removal of mountaintops to expose coal seams, and disposing of associated mining overburden in adjacent "valley fills." Valley fills occur in steep terrain where there are limited disposal alternatives. Mountaintop removal mining combines area and contour strip mining methods. In areas with rolling or steep terrain with
5440-425: The potential to spontaneously ignite. Because most coal refuse harbors toxic components, it is not easily reclaimed by replanting with plants like beach grasses. The use of sophisticated sensing equipment to monitor air quality is common and has replaced the use of small animals such as canaries, often referred to as " miner's canaries ". In the United States, the increase in technology has significantly decreased
5525-399: The risks of rock falls, explosions, and unhealthy air quality. Gases released during the mining process can be recovered to generate electricity and improve worker safety with gas engines . Another innovation in recent years is the use of closed circuit escape respirators , respirators that contain oxygen for situations where mine ventilation is compromised. Statistical analyses performed by
5610-565: The seam in a pattern following the contours along a ridge or around the hillside. This method is most commonly used in areas with rolling to steep terrain. It was once common to deposit the spoil on the downslope side of the bench thus created, but this method of spoil disposal consumed much additional land and created severe landslide and erosion problems. To alleviate these problems, a variety of methods were devised to use freshly cut overburden to refill mined-out areas. These haul-back or lateral movement methods generally consist of an initial cut with
5695-432: The spoil deposited downslope or at some other site and spoil from the second cut refilling the first. A ridge of undisturbed natural material 15 to 20 ft (5 to 6 m) wide is often intentionally left at the outer edge of the mined area. This barrier adds stability to the reclaimed slope by preventing spoil from slumping or sliding downhill. The limitations of contour strip mining are both economic and technical. When
5780-536: The station in 2009. It closed in 2011 after it became clear that it was not financially viable. Plans for a UK Government funded project to convert Longannet to CCS were abandoned in 2011 and no further plans for CCS at Longannet were announced. In 2003, Longannet was named as Scotland's biggest polluter in a report by the Scottish Environment Protection Agency (SEPA). The station produced up to 4,350 tonnes of ash per day. This
5865-497: The station's particulate emissions. In the late 1980s, the station's units were fitted with sulphur trioxide (SO 3 ) conditioning equipment to lower the fly ash 's electrical resistivity. This was to ensure the station maintained allowable particulate emissions. Between 1989 and 1994, the station's ESPs were given a major refurbishment. This meant that the SO 3 conditioning equipment did not need to be operated as frequently to maintain
5950-476: The surface or overburden, of the mining area. The overburden is then removed by draglines or by shovel and truck. Once the coal seam is exposed, it is drilled, fractured and thoroughly mined in strips. The coal is then loaded onto large trucks or conveyors for transport to either the coal preparation plant or directly to where it will be used. Most open cast mines in the United States extract bituminous coal . In Canada, Australia, and South Africa, open cast mining
6035-412: The time, such as a horse-powered bucket and chain drainage system. But the finest achievement was The Moat Pit at Culross , a shaft (actually three concentric stone towers to protect a central shaft from the ingress of the sea) constructed in the Firth of Forth on the foreshore 400m to the south of the high water mark at the west end of Culross. The primary purpose was to promote natural ventilation through
6120-524: The two basic methods of mining. The choice of mining method depends primarily on depth, density, overburden, and thickness of the coal seam; seams relatively close to the surface, at depths less than approximately 55 m (180 ft), are usually surface mined. Coal that occurs at depths of 55 to 90 m (180 to 300 ft) are usually deep mined, but in some cases surface mining techniques can be used. For example, some western U.S. coal that occur at depths in excess of 60 m (200 ft) are mined by
6205-452: The use of draglines , trucks, conveyors , hydraulic jacks , and shearers. The coal mining industry has a long history of significant negative environmental impacts on local ecosystems, health impacts on local communities and workers, and contributes heavily to the global environmental crises, such as poor air quality and climate change . For these reasons, coal has been one of the first fossil fuels to be phased out of various parts of
6290-577: The water level has reached the now closed adit entrance at Longannet, and the UK imported large quantities of foreign coal to burn in Longannet Power Station until its closure in 2016. One of the first large scale early workings of the Upper Hirst also ended in a flood. The Upper Hirst outcropped to the north, west and south east of Culross and was mined extensively by George Bruce (later Sir George Bruce of Carnock ) and his sons between 1575 and 1676, using methods technically advanced for
6375-406: The workings which extended under the Firth of Forth to the south. 19th century historians postulated that the circular tower was used for loading coal directly onto ships, but there is no archaeological evidence for this; most of the coal was used locally heating salt pans for distilling salt. On one occasion the mine was visited by King James VI of Scotland , who entered from the shore and emerged on
6460-441: The world, with official statistics claiming that 6,027 deaths occurred in 2004. To compare, 28 deaths were reported in the U.S. in the same year. Coal production in China is twice that in the US, while the number of coal miners is around 50 times that of the US, making deaths in coal mines in China 4 times as common per worker (108 times as common per unit output) as in the US. Mine disasters have still occurred in recent years in
6545-404: Was 183 metres (600 ft) tall; the station did not have cooling towers , instead using water drawn from the Firth of Forth at a rate of 327,000 cubic metres (11,500,000 cu ft) per hour for the station's cooling condensers . The water was passed through coarse screens and then circulated by four electrically driven pumps. Once circulated through the station's condensers, the water
6630-623: Was delivered either by road or rail to the station's coal store, which had the capacity to hold up to 2,000,000 tonnes. It was then fed from the coal store to the boiler house by a conveyor belt capable of carrying 3,500 tonnes of coal per hour. Each of the four boilers was serviced by eight pulverising units, each capable of processing 40 tonnes of coal an hour. The front-wall-fired Foster Wheeler boilers could each burn around 250 tonnes of coal an hour at full load. There were two forced draft and two induced draft fans on each boiler. Each boiler provided around 1,800 tonnes per hour of steam at
6715-462: Was discharged into a mile long cooling channel, where heat was dissipated before the water reached a wide part of the Forth. Water used by the boilers was on a different cycle, and had to be deionised . Losses from this supply were made up by a plant capable of treating 218 cubic metres (7,700 cu ft) of water per hour. The station was fitted with electrostatic precipitators (ESP) to reduce
6800-455: Was handed over to Scottish Power following privatisation. After failing to win a contract from National Grid , the station closed on 24 March 2016. The station was a regional landmark, dominating the Forth skyline with its 183 m (600 ft) chimney stack. Longannet lacked cooling towers , having instead used water from the River Forth for cooling. On 4 February 2021, the boiler house, turbine hall and control room were demolished in
6885-531: Was mined, and 375.1 million tonnes was exported. In 2013/14, coal provided about 69% of Australia's electricity production. In 2013, Australia was the world's fifth-largest coal producer, after China, the United States, India, and Indonesia. However, in terms of proportion of production exported, Australia is the world's second largest coal exporter, as it exports roughly 73% of its coal production. Indonesia exports about 87% of its coal production. A court in Australia has cited climate change in ruling against
6970-400: Was not begun. At Manor Powis , for example, the useful seams in the Limestone Coal Group were at a depth of about 400 metres, and included valuable anthracite; the Upper Hirst was above this and as well as being mined at mid-shaft in the old colliery, was reached by a pair of sloping adits constructed near the bank of the River Forth . The slope of the seam was followed for some distance down
7055-492: Was operated by Scottish Power , a subsidiary of Iberdrola . It paid £40M per year in connection charges to National Grid due to its distance from South England. The plant opted in to the UK Transitional National Plan, placing limits on its sulphur dioxide, nitrous oxides and particulates emissions. The plant tested additional technologies that could have permitted it to operate beyond 2020 under
7140-469: Was piped to ash lagoons surrounding the nearby Preston Island . This was then landscaped and used to claim land from the Firth of Forth. To improve environmental emissions, Longannet was fitted with 'Low-NOx' burners to limit the formation of oxides of nitrogen and a 'gas reburn system' that used natural gas to convert NOx into nitrogen and water vapour . Longannet used to burn up to 65,000 tonnes of treated and dried sewage sludge per year, which has
7225-524: Was the highest of any power station in Scotland. The station began generating electricity in 1970, and when it became fully operational it was the largest coal-fired station in Europe. At the time of closure it was the third largest, after Bełchatów in Poland and Drax in England, and the 21st most polluting. Longannet was operated by the South of Scotland Electricity Board until 1990, when its operation
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