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Coal Refuse
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 kilograms of waste material remains, which includes some lost coal that 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 the potential to spontaneously ignite. Because most coal refuse harbors toxic components, it is not easily reclaimed by replanting with plants like beach grasses. Gob (short for "garbage of bituminous") has about four times as much toxic mercury and more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Waste Pile West Of Trevorton, Pennsylvania Far Shot 2
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 formed when dead plant matter decays into peat and 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. Many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until 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 iro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with Thailand, Myanmar, and Indonesia. Modern humans arrived on the Indian subcontinent from Africa no later than 55,000 years ago., "Y-Chromosome and Mt-DNA data support the colonization of South Asia by modern humans originating in Africa. ... Coalescence dates for most non-European populations average to between 73–55 ka.", "Modern human beings—''Homo sapiens''—originated in Africa. Then, interm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martin County Coal Slurry Spill
The Martin County coal slurry spill was a mining accident that occurred after midnight on October 11, 2000, when the bottom of a coal slurry impoundment owned by Massey Energy in Martin County, Kentucky, broke into an abandoned underground mine below. The slurry came out of the mine openings, sending an estimated of slurry down two tributaries of the Tug Fork River. By morning, Wolf Creek was oozing with the black waste; on Coldwater Fork, a stream became a expanse of thick slurry. The spill, which contained arsenic and mercury, killed everything in the water. It was over five feet deep in places and covered nearby residents' yards. The spill polluted hundreds of miles () of the Big Sandy River and its tributaries and the Ohio River. The water supply for over 27,000 residents was contaminated, and all aquatic life in Coldwater Fork and Wolf Creek was killed. The spill was 30 times larger than the Exxon Valdez oil spill, spilling . It was one of the worst environmental disas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aberfan Disaster
The Aberfan disaster was the catastrophic collapse of a colliery spoil tip on 21 October 1966. The tip had been created on a mountain slope above the Welsh village of Aberfan, near Merthyr Tydfil, and overlaid a natural spring. Heavy rain led to a build-up of water within the tip which caused it to suddenly slide downhill as a slurry, killing 116 children and 28 adults as it engulfed Pantglas Junior School and a row of houses. The tip was the responsibility of the National Coal Board (NCB), and the subsequent inquiry placed the blame for the disaster on the organisation and nine named employees. There were seven spoil tips on the hills above Aberfan; Tip 7—the one that slipped onto the village—was started in 1958 and, at the time of the disaster, was high. In contravention of the NCB's procedures, the tip was partly based on ground from which springs emerged. After three weeks of heavy rain the tip was saturated and approximately of spoil slipped down the side of the hil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptocurrency Mining
A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it. It is a decentralized system for verifying that the parties to a transaction have the money they claim to have, eliminating the need for traditional intermediaries, such as banks, when funds are being transferred between two entities. Individual coin ownership records are stored in a digital ledger, which is a computerized database using strong cryptography to secure transaction records, control the creation of additional coins, and verify the transfer of coin ownership. Despite their name, cryptocurrencies are not considered to be currencies in the traditional sense, and while varying treatments have been applied to them, including classification as commodities, securities, and currencies, cryptocurrencies are generally viewed as a distin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Coal-fired Power Stations In The United States
This is a list of the operational coal-fired power stations in the United States. Coal generated 23% of electricity in the United States in 2021, an amount similar to that from renewable energy or nuclear power, but about half of that generated by natural gas plants. Coal was 19% of generating capacity. Between 2010 and May 2019, 290 coal power plants, or 40% of the U.S. coal generating capacity, closed. This was mainly due to competition from other generating sources, primarily cheaper and cleaner natural gas, as a result of the fracking boom, which has replaced so many coal plants that natural gas in 2019 accounted for 40% of the total electricity generation in the U.S., as well as the decrease in the cost of renewables. However, some coal plants remain profitable because costs to other people due to the health and environmental impact of the coal industry (estimated to average 5 cents per kWh) is not priced into the cost of generation. Some coal plants are consideri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottom Ash
Bottom ash is part of the non- combustible residue of combustion in a power plant, boiler, furnace or incinerator. In an industrial context, it has traditionally referred to coal combustion and comprises traces of combustibles embedded in forming clinkers and sticking to hot side walls of a coal-burning furnace during its operation. The portion of the ash that escapes up the chimney or stack is, however, referred to as ''fly ash''. The clinkers fall by themselves into the bottom hopper of a coal-burning furnace and are cooled. The above portion of the ash is also referred to as bottom ash. Most bottom ash generated at U.S. power plants is stored in ash ponds, which can cause serious environmental damage if they experience structural failures. Ash handling processes In a conventional water impounded hopper (WIH) system, the clinker lumps get crushed to small sizes by clinker grinders mounted under water and fall down into a trough from where a water ejector takes them out to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluidized Bed
A fluidized bed is a physical phenomenon that occurs when a solid particulate substance (usually present in a holding vessel) is under the right conditions so that it behaves like a fluid. The usual way to achieve a fluidize bed is to pump pressurized fluid into the particles. The resulting medium then has many properties and characteristics of normal fluids, such as the ability to free-flow under gravity, or to be pumped using fluid technologies. The resulting phenomenon is called fluidization. Fluidized beds are used for several purposes, such as fluidized bed reactors (types of chemical reactors), solids separation, fluid catalytic cracking, fluidized bed combustion, heat or mass transfer or interface modification, such as applying a coating onto solid items. This technique is also becoming more common in aquaculture for the production of shellfish in integrated multi-trophic aquaculture systems. Properties A fluidized bed consists of fluid-solid mixture that exhibits fluid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jharia Coalfield
Jharia coalfield is a large coal field located in the east of India in Jharia, Jharkhand. Jharia represents the largest coal reserves in India having estimated reserves of 19.4 billion tonnes of coking coal. The coalfield is an important contributor to the local economy, employing much of the local population either directly or indirectly. The fields have suffered a coal bed fire since at least 1916, resulting in 37 millions tons of coal consumed by the fire, and significant ground subsidence and water and air pollution in local communities including the city of Jharia. The resulting pollution has led to a government agency designated for moving local populations, however, little progress has been made in the relocation. Coal field The coal field lies in the Damodar River Valley, and covers about 110 square miles (280 square km), and produces bituminous coal suitable for coke. Most of India's coal comes from Jharia. Jharia coal mines are India's most important storehouse of prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tailings
In mining, tailings are the materials left over after the process of separating the valuable fraction from the uneconomic fraction (gangue) of an ore. Tailings are different to overburden, which is the waste rock or other material that overlies an ore or mineral body and is displaced during mining without being processed. The extraction of minerals from ore can be done two ways: placer mining, which uses water and gravity to concentrate the valuable minerals, or hard rock mining, which pulverizes the rock containing the ore and then relies on chemical reactions to concentrate the sought-after material. In the latter, the extraction of minerals from ore requires comminution, i.e., grinding the ore into fine particles to facilitate extraction of the target element(s). Because of this comminution, tailings consist of a slurry of fine particles, ranging from the size of a grain of sand to a few micrometres. Mine tailings are usually produced from the mill in slurry form, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluidized Bed Combustion
Fluidized bed combustion (FBC) is a combustion technology used to burn solid fuels. In its most basic form, fuel particles are suspended in a hot, bubbling fluidity bed of ash and other particulate materials (sand, limestone etc.) through which jets of air are blown to provide the oxygen required for combustion or gasification. The resultant fast and intimate mixing of gas and solids promotes rapid heat transfer and chemical reactions within the bed. FBC plants are capable of burning a variety of low-grade solid fuels, including most types of coal, coal waste and woody biomass, at high efficiency and without the necessity for expensive fuel preparation (e.g., pulverising). In addition, for any given thermal duty, FBCs are smaller than the equivalent conventional furnace, so may offer significant advantages over the latter in terms of cost and flexibility. FBC reduces the amount of sulfur emitted in the form of SO''x'' emissions. Limestone is used to precipitate out sulfate du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthracite
Anthracite, also known as hard coal, and black coal, is a hard, compact variety of coal that has a submetallic luster. It has the highest carbon content, the fewest impurities, and the highest energy density of all types of coal and is the highest ranking of coals. Anthracite is the most metamorphosed type of coal (but still represents low-grade metamorphism), in which the carbon content is between 86% and 97%. The term is applied to those varieties of coal which do not give off tarry or other hydrocarbon vapours when heated below their point of ignition. Anthracite ignites with difficulty and burns with a short, blue, and smokeless flame. Anthracite is categorized into standard grade, which is used mainly in power generation, high grade (HG) and ultra high grade (UHG), the principal uses of which are in the metallurgy sector. Anthracite accounts for about 1% of global coal reserves, and is mined in only a few countries around the world. The Coal Region of northeastern P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
