Surface coal mining in Wyoming in the United States of America. The State of Wyoming ( is a sparsely populated state in the western region of the United States. The United States of America —commonly referred to as the

Coal mining is the extraction or removing of coal from the earth by mining. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Mining is the extraction of valuable Minerals or other geological materials from the earth usually (but not always from an Ore body When coal is used for fuel in power generation it is referred to as steaming or thermal coal. Fuel is any material that is burned or altered in order to obtain energy Coal that is used to create coke for steel manufacturing is referred to as coking or metallurgical coal. Coke may refer to Coke (fuel, a solid carbonaceous residue derived from destructive distillation of coal Petroleum coke, a solid carbon Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 Coke is a solid Carbonaceous material derived from Destructive distillation of low-ash low-sulfur Bituminous coal. ^[1] In the United States, UK, and South Africa, a coal mine and its accompanying structures are collectively known as a colliery. The United States of America —commonly referred to as the The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa In Australia, 'colliery' usually only refers to an underground coal mine. For a topic outline on this subject see List of basic Australia topics. ^[2]

Methods of extraction

The most economical method of coal extraction from coal seams depends on the depth and quality of the seams, and also the geology and environmental factors of the area being mined. Geology (from Greek γη gê, "earth" and λόγος Logos, "speech" lit Coal mining processes are generally differentiated by whether they operate on the surface or underground. Many coals extracted from both surface and underground mines require washing in a coal preparation plant. A Coal Preparation Plant (CPP is a facility that washes Coal of Soil and rock, preparing it for Transport to market

Modern surface mining

Trucks loaded with coal at the Cerrejón coal mine in Colombia. Cerrejón is a coal mine located in the Guajira department in the north of Colombia. Colombia (kəˈlʌmbɪə officially the Republic of Colombia () is a country in northwestern South America.

When coal seams are near the surface, it may be economical to extract the coal using open cut (also referred to as open cast or open pit) mining methods. Open-pit mining, also known as opencast mining and open-cut mining and strip mining, refers to a method of extracting rock or Minerals Typically, for coal, strip mining is used. Surface mining is a type of Mining in which soil and rock overlying the mineral deposit are removed Strip mining exposes the coal by the advancement of an open pit or strip. The earth above the coal seam(s) is known as overburden. Overburden is the term used in Mining to describe material that lies above the area of economic interest e A strip of overburden next to the previously mined strip is usually drilled. For a detailed diagram of a Petroleum drilling rig, See Drilling rig (petroleum A drilling rig is a machine which creates holes (usually called The drill holes are filled with explosives and blasted. The overburden is then removed using large earthmoving equipment such as draglines, shovel and trucks, excavator and trucks, or bucket-wheels and conveyors. Dragline excavation systems are Heavy equipment used in Civil engineering and surface Mining. A Power shovel (also called a Stripping or Front Shovel in some markets is a bucket equipped machine usually electrically powered used for digging and loading earth or fragmented An excavator is an Engineering vehicle consisting of an articulated arm (boom stick bucket and Cab mounted on a Pivot (a rotating platform like a Bucket-wheel excavators are Heavy equipment used in Surface mining and Civil engineering. 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 as a strip known as a 'block'. This 'block' of coal may be drilled and blasted (if hard) or otherwise loaded on to trucks or conveyors for transport to 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.

Open cast coal mining recovers a greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited. Opencast coal mines can cover many square kilometers. ^[3]

Most open cast mines in the United States extract bituminous coal. The United States of America —commonly referred to as the Bituminous coal is a relatively soft Coal containing a tarlike substance called Bitumen. In South Wales open casting for steam coal and anthracite is practiced. South Wales (De Cymru is an area of Wales bordered by England and the Bristol Channel to the east and south and Mid Wales and West Wales Anthracite ( Greek Ανθρακίτης literally "a type of coal" from Anthrax, coal is a hard compact variety of mineral Coal that has a high In Australia and South Africa open cast mining is used for both thermal and metallurgical coals. For a topic outline on this subject see List of basic Australia topics. The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa Open-pit mining, also known as opencast mining and open-cut mining and strip mining, refers to a method of extracting rock or Minerals Surface mining accounts for around 80% of production in Australia, while in the USA it is used for about 67% of production. The United States of America —commonly referred to as the Globally, about 40% of coal production involves surface mining. ^[4]

Mountaintop removal is a form of surface mining that takes place at the topmost portion of a mountain, and is a technique that is commonly applied in Appalachia in the United States. Mountaintop removal mining ( MTR) often referred to in the industry as mountaintop mining/valley fills (MTM/VF is a form of Surface mining that involves an Appalachia is a term used to describe a region in the eastern United States that stretches from southern New York state to northern Alabama, The United States of America —commonly referred to as the Utilized for the past 30 years, mountaintop mining involves removing the highest part of the mountain for the maximum recovery of coal. The process is highly controversial for the drastic changes in topography, the practice of hollow fills, or filling in valleys with mining debris, and for covering streams and disrupting ecosystems. ^[5]

Underground mining

Main article: Underground mining

Coal wash plant in Clay County, Kentucky. Clay County is a County located in the US state of Kentucky. It was formed in 1807 The Commonwealth of Kentucky ( is a state located in the East Central United States of America.

Most coal seams are too deep underground for opencast mining and mining these seams involves underground mining. Underground mining currently accounts for about 60% of world coal production. ^[6] 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 coal mine roof. Room and pillar is a Mining system in which the mined material is extracted across a horizontal plane while leaving "pillars" of untouched material to support Room and pillar is a Mining system in which the mined material is extracted across a horizontal plane while leaving "pillars" of untouched material to support 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 referred to as second mining or retreat mining is commonly started. Retreat mining is a term used to reference the final phase of an underground Mining technique known as Room and pillar mining This is when miners remove the coal in the pillars, thereby recovering as much coal from the coal seam as possible. A work area that is 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 other equipment have left a work area. The mobile roof supports are similar to 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 legs shorten, and the mobile roof supports travel out to a safe area. The mine roof typically collapses once the mobile roof supports leave an area.

There are four major underground mining methods:

• Longwall mining – accounts for about 50% of underground production. Longwall mining is a form of underground Coal mining where a long wall (typically about 250-400 m long of coal is mined in a single slice (typically 1-2 m thick The longwall shearer has a face of 1,000 feet (300 m) or more. It is a sophisticated machine with a rotating drum that moves mechanically back-and-forth across a wide coal seam. The loosened coal falls onto a pan line that takes the coal to the conveyor belt for removal from the work area. Longwall systems have their own hydraulic roof supports for overlying rock that advance with the machine as mining progresses. As the longwall mining equipment moves forward, overlying rock that is no longer supported by the coal that has been removed is allowed to fall behind the operation in a controlled manner. The supports make possible high levels of production and safety. Sensors detect how much coal remains in the seam while robotic controls enhance efficiency. Longwall systems allow a 60-to-100% coal recovery rate where the surrounding geology allows their use.

• Continuous mining– Utilize a machine with a large rotating steel drum equipped with tungsten carbide teeth that scrape coal from the seam. Room and pillar is a Mining system in which the mined material is extracted across a horizontal plane while leaving "pillars" of untouched material to support Operating in a “room and pillar” (also known as “bord and pillar”) system – where the mine is divided into a series of 20-to-30 foot “rooms” or work areas cut into the coalbed – it can mine as much as five tons of coal a minute – more than a non-mechanised miner of the 1920s would produce in an entire day. Continuous miners account for about 45% of underground coal production, and also utilize conveyors to transport the removed coal from the seam. Remote controlled continuous miners are used to work in a variety of difficult seams and conditions and robotic versions controlled by computers are becoming increasingly common.

• Blast mining – An older practice that uses explosives such as dynamite to break up the coal seam, after which the coal is gathered and loaded onto shuttle cars or conveyors for removal to a central loading area. An explosive material is a material that either is chemically or otherwise Energetically unstable or produces a sudden expansion of the material usually accompanied Dynamite is an explosive based on the explosive potential of Nitroglycerin, initially using Diatomaceous earth (kieselgur US Spelling kieselguhr This process consists of a series of operations that begins with “cutting” the coalbed so it will break easily when blasted with explosives. This type of mining accounts for less than 5% of total underground production in the U. S. today.

• Shortwall mining– A method that accounts for less than 1% of deep coal production, shortwall involves the use of a continuous mining machine with moveable roof supports, similar to longwall. The continuous miner shears coal panels 150-200 feet wide and more than a half-mile long, depending on other things like the strata of the Earth and the transverse waves.

• Retreat mining- A modern method in which the ceiling of the mine is held up by wooden beams. Retreat mining is a term used to reference the final phase of an underground Mining technique known as Room and pillar mining The beams are removed allowing the ceiling to collapse so miners can reach the coal. This is one of the most dangerous forms of mining. There is no telling when the ceiling will collapse so it can be easy for a miner to be crushed or trapped within the mine.

Production

Coal is mined commercially in over 50 countries. Over 4 970 Mt of hard coal is currently produced, a nearly 80% increase over the past 25 years. ^[7] In 2005, the world production of brown coal and lignite was 906 Mt, with Germany the world’s largest brown coal producer. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe.

Coal production has grown fastest in Asia, while Europe has declined. The top five coal mining nations (figures in brackets are 2006 estimate of hard coal production)^[8] are:

• China (2 482 Mt)
• USA (990 Mt)
• India (427 Mt)
• Australia (309 Mt)
• South Africa (244 Mt)

Most coal production is used in the country of origin, with around 16% of hard coal production being exported. Talk People's Republic of China) PEOPLE'S REPUBLIC OF CHINA ARTICLE GUIDELINES The United States of America —commonly referred to as the India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country For a topic outline on this subject see List of basic Australia topics. The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa

Global coal production is expected to reach 7 Gt in 2030, with China accounting for most of this increase. Steam coal production is projected to reach around 5200 Mt; coking coal 620 Mt; and brown coal 1200 Mt. ^[9]

Coal reserves are available in almost every country worldwide, with recoverable reserves in around 70 countries. At current production levels, proven coal reserves are estimated to last 147 years. ^[10]

History

Main article: History of coal mining

The oldest continuously worked deep-mine in the UK and possibly the world is Tower Colliery at the northern end of the South Wales valleys in the heart of the South Wales coalfield. Large-scale coal mining developed during the Industrial Revolution, and coal provided the main source of Primary energy The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located Tower Colliery was the oldest continuously worked deep- coal mine in the United Kingdom, and possibly the world and the only mine of its kind remaining in the The South Wales Valleys (Cymoedd De Cymru are a number of industrialised valleys in South Wales, stretching from eastern Carmarthenshire in the west to western The South Wales Coalfield is a large region of South Wales that is rich with Coal deposits This colliery was started in 1805 and at the end of the 20th century it was bought out by its miners rather than being allowed to be closed. Tower Colliery was finally closed on the 25th January 2008.

The World Championships in coal-carrying take place every Easter Monday, at Ossett, West Yorkshire, UK. Easter Monday is the day after Easter Sunday and is celebrated as a Holiday in some largely Christian cultures especially Roman Catholic Ossett (pronounced /ɒsɪt/ is a Market town within the Metropolitan borough of the City of Wakefield, in West Yorkshire, England West Yorkshire is a Metropolitan county within the Yorkshire and the Humber region of England with a population of The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located The race starts from the site of the old Savile & Shaw Cross colliery.

The first commercial coal mines in the United States were started in 1748 in Midlothian, Virginia, near Richmond, Virginia. Midlothian is an unincorporated community in Chesterfield County, Virginia, United States. This article is about the city of Richmond the capital of the Commonwealth of Virginia. ^[11]

In the 1880s, Coal-cutting machines became available (prior to that, coal was mined underground by hand using a pick and shovel. )

By 1912, surface mining was underway with steam shovels specifically designed for coal mining. Surface mining is a type of Mining in which soil and rock overlying the mineral deposit are removed

Modern mining

Technological advancements have made coal mining today more productive than it has ever been. To keep up with technology and to extract coal as efficiently as possible modern mining personnel must be highly skilled and well trained in the use of complex, state-of-the-art instruments and equipment. This article is about the Amiga demo for other uses see State of the art (disambiguation. Future coal miners have to be highly educated and many jobs require four-year college degrees. Computer knowledge has also become greatly valued within the industry as most of the machines and safety monitors are computerized.

In the United States, the increase in technology has significantly decreased the mining workforce from 335,000 coal miners working at 7,200 mines fifty years ago to 104,824 miners working in fewer than 2,000 mines today. The United States of America —commonly referred to as the As some might see this as a sign that coal is a declining industry its advances has reported an 83% increase of production from 1970 to 2004.

Dangers to miners

Historically, coal mining has been a very dangerous activity and the list of historical coal mining disasters is a long one. A mining accident is an Accident that occurs in the process of Mining minerals Open cut hazards are principally mine wall failures and vehicle collisions; underground mining hazards include roof collapse and gas explosions. This page is about the physical properties of gas as a state of matter Most of these risks can be greatly reduced in modern mines, and multiple fatality incidents are now rare in some parts of the developed world. ^[12]

However, in lesser developed countries and some developed 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 the world, with official statistic 6,027 deaths in 2004. The People's Republic of China is the largest consumer of Coal in the world and is about to become the largest user of coal-derived electicity getting ^[13] To compare, the USA reported 28 deaths in the same year. The United States of America —commonly referred to as the ^[14] Coal production in China is twice that of the United States,^[15] while the number of coal miners is around 50 times that of the USA, making deaths in coal mines in China 4 times as common per worker (50 times as common per unit output) as in the USA.

When compared to industrial countries such as China, the U. S. fatality rate is low. However in 2006 fatal work injuries among U. S. miners doubled from the previous year, totaling 47. ^[16] These figures can in part be attributed to the Sago Mine disaster. The Sago Mine disaster was a Coal mine Explosion on January 2, 2006, in the Sago Mine (ˈseɪgoʊ in Sago, West Virginia The recent mine accident in Utah's Crandall Canyon Mine, where nine miners were killed and six entombed, speaks to the increase in occupational risks faced by U. The State of Utah (ˈjuːtɔː or) is a western state of the United States. The Crandall Canyon Mine, formerly Genwal Mine, was an underground Bituminous Coal mine in northwestern Emery County Utah. S. miners. ^[17]

Chronic lung diseases, such as pneumoconiosis (black lung) were once common in miners, leading to reduced life expectancy. lung is the essential Respiration organ in air-breathing Animals including most Tetrapods a few Fish and a few Snails The most primitive Pneumoconiosis is an Occupational lung disease caused by the Inhalation of dust Life expectancy is the average number of years of life remaining at a given age In some mining countries black lung is still common, with 4000 new cases of black lung every year in the USA (4% of workers annually) and 10 000 new cases every year in China (0. 2% of workers). ^[18] Rates may be higher than reported in some regions.

Build-ups of a hazardous gas are known as damps, possibly from the German word "Dampf" which means steam or vapor:

• Black damp: a mixture of carbon dioxide and nitrogen in a mine can cause suffocation. Blackdamp (also known as stythe or choke damp) is a mixture of unbreathable gases formed when oxygen is removed from an enclosed Atmosphere and largely Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14
• After damp: similar to black damp, an after damp consists of carbon dioxide and nitrogen and forms after a mine explosion. Afterdamp is the toxic mixture of gases left in a mine following an explosion caused by Firedamp.
• Fire damp: consists of mostly methane, a flammable gas. Firedamp is a Flammable Gas found in coal mines. It is actually the name given to a number of flammable gases including Methane. Methane is a Chemical compound with the molecular formula. It is the simplest Alkane, and the principal component of Natural gas.
• Stink damp: so named for the rotten egg smell of the sulfur, a stink damp can explode. Hydrogen sulfide (or hydrogen sulphide) is the Chemical compound with the formula H 2 S.
• White damp: air containing carbon monoxide which is toxic, even at low concentrations]

See also: Mining accidents

Safer times in modern mining

Improvements in mining methods (e. Carbon monoxide, with the chemical formula CO is a colorless odorless tasteless yet highly toxic Gas. A mining accident is an Accident that occurs in the process of Mining minerals g. longwall mining), hazardous gas monitoring (such as safety-lamps or more modern electronic gas monitors), gas drainage, and ventilation have reduced many of the risks of rock falls, explosions, and unhealthy air quality. A safety lamp is any of several types of lamp, which are designed to be safe to use in Coal mines These lamps are designed to operate in air that may contain Statistical analyses performed by the U. S. 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. The Mine Safety and Health Administration ( MSHA) is an agency of the United States Department of Labor which administers the provisions of the Federal Mine However, according to the Bureau of Labor Statistics, mining remains the second most dangerous occupation in America. The Bureau of Labor Statistics ( BLS) a unit of the United States Department of Labor, is the principal fact-finding agency for the U ^[19]

Environmental impacts

Main article: Environmental effects of coal

Coal mining can result in a number of adverse effects on the environment. There are a number of adverse environmental effects of coal mining and burning Environmental ethics is the part of Environmental philosophy which considers the ethical relationship between Human beings and the Natural environment Open cast coal mines leaves areas of land that is no longer usable and leaves a scarred landscape with no scenic value. Rehabilitation can mitigate some of these concerns. Mine tailing dumps produce acid mine drainage which can seep into waterways and aquifers with consequences on ecological and human health. Acid mine drainage ( AMD) or acid rock drainage ( ARD) refers to the outflow of Acidic water from (usually abandoned Metal mines Ecology (from Greek grc οἶκος oikos, "house(hold" and grc -λογία -logia) is the scientific study of Subsidence of land surfaces due to collapse of mine tunnels can also occur. During the mining operation methane, a potent greenhouse gas and a constituent of fire damp, can be released. Methane is a Chemical compound with the molecular formula. It is the simplest Alkane, and the principal component of Natural gas. Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared Firedamp is a Flammable Gas found in coal mines. It is actually the name given to a number of flammable gases including Methane.

See also

• Acid mine drainage
• Black lung disease
• Coal Measures
• Coal mining debate
• Coal slurry impoundment
• Coal-mining region
• Hurrying
• Mine fire
• Problems in coal mining
• World Coal Institute
• Coal mining in Australia

References

Further reading

• Daniel Burns. The modern practice of coal mining (1907)
• Hughes. Herbert W, A Text-Book of Mining: For the Use of Colliery Managers and Others (London, many editions 1892-1917), the standard British textbook for its era.
• James Tonge. The principles and practice of coal mining (1906)
• Charles V. Nielsen and George F. Richardson. 1982 Keystone Coal Industry Manual (1982)
• Hayes, Geoffrey. Coal Mining (2004), 32 pp
• A. K. Srivastava. Coal Mining Industry in India (1998) (ISBN 81-7100-076-2)
• Chirons, Nicholas P. Coal Age Handbook of Coal Surface Mining (ISBN 0-07-011458-7)
• Saleem H. Ali. Minding our Minerals, 2006. [1]
• National Energy Information Center, Greenhouse Gases, Climate Change, Energy, <http://www.eia.doe.gov/oiaf/1605/ggccebro/chapter1.html>. Retrieved on 16 October 2007 

• The Department of Trade and Industry, The Coal Authority, <http://www.coal.gov.uk/resources/cleanercoaltechnologies/CoalMineandbedmethane.cfm>. Retrieved on 16 October 2007 

External links

• Abandoned Mine Research
• of Wollongong - educational resource on longwall mining
• National Coal Mining Museum for England
• World Coal Institute - Coal Mining
• NIOSH Coal Workers' Health Surveillance Program
• Purdue University - Petroleum and Coal