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99-414: It is a coal-fired station with the largest unit capacity of any European power station: 865 MW . The hard coal it burns arrives several times a day by rail or ship to its own dock on the river Weser from all over the world to be stored until use; the station stockpiles a month's coal supply. At full capacity Heyden burns 265 tonnes of coal every hour, and is seldom not running as it supplies most of

198-406: A North Rhine-Westphalian building or structure is a stub . You can help Misplaced Pages by expanding it . This article about a Germany power station is a stub . You can help Misplaced Pages by expanding it . Fossil fuel power plant 2021 world electricity generation by source. Total generation was 28 petawatt-hours . A fossil fuel power station is a thermal power station which burns

297-407: A flue-gas desulfurization plant, and cleans 99% of the dust from its emissions and 90% of the sulphur but none of the carbon dioxide greenhouse gas. Heyden outputs 2700 tonnes of steam per hour, has 32 pulverised coal burners, and its chimney is 225 metres high. 52°22′55″N 8°59′54″E  /  52.38194°N 8.99833°E  / 52.38194; 8.99833 This article about

396-412: A fossil fuel , such as coal , oil , or natural gas , to produce electricity . Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy , which then operates an electrical generator . The prime mover may be a steam turbine , a gas turbine or, in small plants, a reciprocating gas engine . All plants use the energy extracted from the expansion of

495-400: A half-life of 444 years, and Hg with a half-life of 46.612 days. Most of the remaining radioisotopes have half-lives that are less than a day. Hg occurs naturally in tiny traces as an intermediate decay product of U . Hg and Hg are the most often studied NMR -active nuclei, having spins of 1 ⁄ 2 and 3 ⁄ 2 respectively. Hg is

594-434: A mercury-aluminium amalgam when the two pure metals come into contact. Since the amalgam destroys the aluminium oxide layer which protects metallic aluminium from oxidizing in-depth (as in iron rusting ), even small amounts of mercury can seriously corrode aluminium. For this reason, mercury is not allowed aboard an aircraft under most circumstances because of the risk of it forming an amalgam with exposed aluminium parts in

693-640: A soft metal , mercury forms very stable derivatives with the heavier chalcogens . Preeminent is mercury(II) sulfide , HgS, which occurs in nature as the ore cinnabar and is the brilliant pigment vermilion . Like ZnS , HgS crystallizes in two forms , the reddish cubic form and the black zinc blende form. The latter sometimes occurs naturally as metacinnabar . Mercury(II) selenide (HgSe) and mercury(II) telluride (HgTe) are known, these as well as various derivatives, e.g. mercury cadmium telluride and mercury zinc telluride being semiconductors useful as infrared detector materials. Mercury(II) salts form

792-577: A chamber 60 feet below the 1800-year-old pyramid known as the Temple of the Feathered Serpent , the third-largest pyramid of Teotihuacan , Mexico, along with "jade statues, jaguar remains, a box filled with carved shells and rubber balls". In Lamanai , once a major city of the Maya civilization , a pool of mercury was found under a marker in a Mesoamerican ballcourt . Aristotle recounts that Daedalus made

891-459: A digital display. Some transit telescopes use a basin of mercury to form a flat and absolutely horizontal mirror, useful in determining an absolute vertical or perpendicular reference. Concave horizontal parabolic mirrors may be formed by rotating liquid mercury on a disk, the parabolic form of the liquid thus formed reflecting and focusing incident light. Such liquid-mirror telescopes are cheaper than conventional large mirror telescopes by up to

990-401: A factor of 100, but the mirror cannot be tilted and always points straight up. Liquid mercury is part of a popular secondary reference electrode (called the calomel electrode ) in electrochemistry as an alternative to the standard hydrogen electrode . The calomel electrode is used to work out the electrode potential of half cells . The triple point of mercury, −38.8344 °C, is

1089-487: A fine filter that collects the ash particles, electrostatic precipitators use an electric field to trap ash particles on high-voltage plates, and cyclone collectors use centrifugal force to trap particles to the walls. A recent study indicates that sulfur emissions from fossil fueled power stations in China may have caused a 10-year lull in global warming (1998-2008). Fossil-fuel power stations, particularly coal-fired plants, are

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1188-402: A fraction of the heat produced during combustion into mechanical work . The rest of the heat, called waste heat , must be released into a cooler environment during the return portion of the cycle. The fraction of heat released into a cooler medium must be equal or larger than the ratio of absolute temperatures of the cooling system (environment) and the heat source (combustion furnace). Raising

1287-534: A hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by the Carnot efficiency and therefore produce waste heat . Fossil fuel power stations provide most of the electrical energy used in the world. Some fossil-fired power stations are designed for continuous operation as baseload power plants , while others are used as peaker plants . However, starting from

1386-480: A laxative and dewormer, and it was used in teething powders for infants. The mercury-containing organohalide merbromin (sometimes sold as Mercurochrome) is still widely used but has been banned in some countries, such as the U.S. Mercury is an ingredient in dental amalgams . Thiomersal (called Thimerosal in the United States) is an organic compound used as a preservative in vaccines , although this use

1485-636: A major source of industrial wastewater . Wastewater streams include flue-gas desulfurization, fly ash, bottom ash and flue gas mercury control. Plants with air pollution controls such as wet scrubbers typically transfer the captured pollutants to the wastewater stream. Ash ponds , a type of surface impoundment, are a widely used treatment technology at coal-fired plants. These ponds use gravity to settle out large particulates (measured as total suspended solids ) from power plant wastewater. This technology does not treat dissolved pollutants. Power stations use additional technologies to control pollutants, depending on

1584-408: A particular fuel. As an example, a new 1500 MW supercritical lignite-fueled power station running on average at half its capacity might have annual CO 2 emissions estimated as: = 1500MW x 0.5 x 100/40 x 101000 kg/TJ x 1year = 1500MJ/s x 0.5 x 2.5 x 0.101 kg/MJ x 365x24x60x60s = 1.5x10 x 5x10 x 2.5 x 1.01 x 3.1536x10 kg = 59.7 x10 kg = 5.97 Mt Thus the example power station

1683-445: A positive charge. One example is Hg 3 (AsF 6 ) 2 containing the Hg 3 cation. Mercury(II) is the most common oxidation state and is the main one in nature as well. All four mercuric halides are known and have been demonstrated to form linear coordination geometry , despite mercury's tendency to form tetrahedral molecular geometry with other ligands. This behavior

1782-433: A serious impact on public health. Power plants remove particulate from the flue gas with the use of a bag house or electrostatic precipitator . Several newer plants that burn coal use a different process, Integrated Gasification Combined Cycle in which synthesis gas is made out of a reaction between coal and water. The synthesis gas is processed to remove most pollutants and then used initially to power gas turbines. Then

1881-494: A significant reduction from the greenhouse gas emissions liability related to only natural disasters in the United States from a single coal-fired power plant. However, as of 2015, no such cases have awarded damages in the United States. Per unit of electric energy, brown coal emits nearly twice as much CO 2 as natural gas, and black coal emits somewhat less than brown. As of 2019 , carbon capture and storage of emissions

1980-459: A variety of complex derivatives with ammonia . These include Millon's base (Hg 2 N ), the one-dimensional polymer (salts of HgNH 2 ) n ), and "fusible white precipitate" or [Hg(NH 3 ) 2 ]Cl 2 . Known as Nessler's reagent , potassium tetraiodomercurate(II) ( K 2 HgI 4 ) is still occasionally used to test for ammonia owing to its tendency to form the deeply colored iodide salt of Millon's base. Mercury fulminate

2079-502: A wooden statue of Aphrodite move by pouring quicksilver in its interior. In Greek mythology Daedalus gave the appearance of voice in his statues using quicksilver. The ancient Greeks used cinnabar (mercury sulfide) in ointments; the ancient Egyptians and the Romans used it in cosmetics . By 500 BC mercury was used to make amalgams (Medieval Latin amalgama , "alloy of mercury") with other metals. Alchemists thought of mercury as

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2178-460: Is a chemical element ; it has symbol Hg and atomic number 80. It is also known as quicksilver and was formerly named hydrargyrum ( / h aɪ ˈ d r ɑːr dʒ ər ə m / hy- DRAR -jər-əm ) from the Greek words hydor ' water ' and argyros ' silver ' , from which its chemical symbol is derived. A heavy , silvery d-block element, mercury is the only metallic element that

2277-474: Is a detonator widely used in explosives . Organic mercury compounds are historically important but are of little industrial value in the western world. Mercury(II) salts are a rare example of simple metal complexes that react directly with aromatic rings. Organomercury compounds are always divalent and usually two-coordinate and linear geometry. Unlike organocadmium and organozinc compounds, organomercury compounds do not react with water. They usually have

2376-475: Is a deceiving baseline for comparison: just the Chernobyl nuclear disaster released, in iodine-131 alone, an estimated 1.76 EBq. of radioactivity, a value one order of magnitude above this value for total emissions from all coal burned within a century, while the iodine-131, the major radioactive substance which comes out in accident situations, has a half life of just 8 days. Mercury (element) Mercury

2475-427: Is a heavy, silvery-white metal that is liquid at room temperature. Compared to other metals, it is a poor conductor of heat, but a fair conductor of electricity. It has a melting point of −38.83 °C and a boiling point of 356.73 °C, both the lowest of any stable metal, although preliminary experiments on copernicium and flerovium have indicated that they have even lower boiling points. This effect

2574-424: Is a relatively cheap fuel. Coal is an impure fuel and produces more greenhouse gas and pollution than an equivalent amount of petroleum or natural gas. For instance, the operation of a 1000-MWe coal-fired power plant results in a nuclear radiation dose of 490 person-rem/year, compared to 136 person-rem/year for an equivalent nuclear power plant, including uranium mining, reactor operation and waste disposal. Coal

2673-562: Is a topical antiseptic used for minor cuts and scrapes in some countries. Today, the use of mercury in medicine has greatly declined in all respects, especially in developed countries. Mercury is still used in some diuretics , although substitutes such as thiazides now exist for most therapeutic uses. In 2003, mercury compounds were found in some over-the-counter drugs , including topical antiseptics , stimulant laxatives, diaper-rash ointment , eye drops , and nasal sprays . The FDA has "inadequate data to establish general recognition of

2772-480: Is an exception, and iron flasks have traditionally been used to transport the material. Several other first row transition metals with the exception of manganese , copper and zinc are also resistant in forming amalgams. Other elements that do not readily form amalgams with mercury include platinum . Sodium amalgam is a common reducing agent in organic synthesis , and is also used in high-pressure sodium lamps. Mercury readily combines with aluminium to form

2871-425: Is around 37% for coal and oil-fired plants, and 56 – 60% (LEV) for combined-cycle gas-fired plants. Plants designed to achieve peak efficiency while operating at capacity will be less efficient when operating off-design (i.e. temperatures too low.) Practical fossil fuels stations operating as heat engines cannot exceed the Carnot cycle limit for conversion of heat energy into useful work. Fuel cells do not have

2970-419: Is burned that significant amounts of these substances are released. A 1,000 MW coal-burning power plant could have an uncontrolled release of as much as 5.2 metric tons per year of uranium (containing 74 pounds (34 kg) of uranium-235 ) and 12.8 metric tons per year of thorium. In comparison, a 1,000 MW nuclear plant will generate about 30 metric tons of high-level radioactive solid packed waste per year. It

3069-550: Is caused by the emission of nitrogen oxides and sulfur dioxide . These gases may be only mildly acidic themselves, yet when they react with the atmosphere, they create acidic compounds such as sulfurous acid , nitric acid and sulfuric acid which fall as rain, hence the term acid rain. In Europe and the US, stricter emission laws and decline in heavy industries have reduced the environmental hazards associated with this problem, leading to lower emissions after their peak in 1960s. In 2008,

Heyden Power Station - Misplaced Pages Continue

3168-403: Is delivered by highway truck , rail , barge , collier ship or coal slurry pipeline . Generating stations adjacent to a mine may receive coal by conveyor belt or massive diesel-electric -drive trucks . Coal is usually prepared for use by crushing the rough coal to pieces less than 2 inches (5 cm) in size. Gas is a very common fuel and has mostly replaced coal in countries where gas

3267-473: Is due to lanthanide contraction and relativistic contraction reducing the orbit radius of the outermost electrons, and thus weakening the metallic bonding in mercury. Upon freezing, the volume of mercury decreases by 3.59% and its density changes from 13.69 g/cm when liquid to 14.184 g/cm when solid. The coefficient of volume expansion is 181.59 × 10 at 0 °C, 181.71 × 10 at 20 °C and 182.50 × 10 at 100 °C (per °C). Solid mercury

3366-499: Is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the Three Mile Island incident . The collective radioactivity resulting from all coal burning worldwide between 1937 and 2040 is estimated to be 2,700,000 curies or 0.101 EBq. During normal operation, the effective dose equivalent from coal plants is 100 times that from nuclear plants. Normal operation however,

3465-421: Is estimated to emit about 6 megatonnes of carbon dioxide each year. The results of similar estimations are mapped by organisations such as Global Energy Monitor , Carbon Tracker and ElectricityMap. Alternatively it may be possible to measure CO 2 emissions (perhaps indirectly via another gas) from satellite observations. Another problem related to coal combustion is the emission of particulates that have

3564-432: Is in decline. Although it was widely speculated that this mercury-based preservative could cause or trigger autism in children, no evidence supports any such link. Nevertheless, thiomersal has been removed from, or reduced to trace amounts in, all U.S. vaccines recommended for children 6 years of age and under, with the exception of the inactivated influenza vaccine. Merbromin (Mercurochrome), another mercury compound,

3663-503: Is known to be liquid at standard temperature and pressure ; the only other element that is liquid under these conditions is the halogen bromine , though metals such as caesium , gallium , and rubidium melt just above room temperature . Mercury occurs in deposits throughout the world mostly as cinnabar ( mercuric sulfide ). The red pigment vermilion is obtained by grinding natural cinnabar or synthetic mercuric sulfide. Exposure to mercury and mercury-containing organic compounds

3762-655: Is malleable and ductile, and can be cut with a knife. Table of thermal and physical properties of liquid mercury: Mercury does not react with most acids, such as dilute sulfuric acid , although oxidizing acids such as concentrated sulfuric acid and nitric acid or aqua regia dissolve it to give sulfate , nitrate , and chloride . Like silver, mercury reacts with atmospheric hydrogen sulfide . Mercury reacts with solid sulfur flakes, which are used in mercury spill kits to absorb mercury (spill kits also use activated carbon and powdered zinc). Mercury dissolves many metals such as gold and silver to form amalgams . Iron

3861-444: Is not economically viable for fossil fuel power stations, and keeping global warming below 1.5 °C is still possible but only if no more fossil fuel power plants are built and some existing fossil fuel power plants are shut down early, together with other measures such as reforestation . In a fossil fuel power plant the chemical energy stored in fossil fuels such as coal , fuel oil , natural gas or oil shale and oxygen of

3960-440: Is sent through controlling valves to a turbine. As the steam expands and cools, its energy is transferred to the turbine blades which turn a generator. The spent steam has very low pressure and energy content; this water vapor is fed through a condenser, which removes heat from the steam. The condensed water is then pumped into the boiler to repeat the cycle. Emissions from the boiler include carbon dioxide, oxides of sulfur, and in

4059-594: Is similar to the Ag ion. The best known mercury halide is mercury(II) chloride , an easily sublimating white solid. Mercury(II) oxide , the main oxide of mercury, arises when the metal is exposed to air for long periods at elevated temperatures. It reverts to the elements upon heating near 400 °C, as was demonstrated by Joseph Priestley in an early synthesis of pure oxygen . Hydroxides of mercury are poorly characterized, as attempted isolation studies of mercury(II) hydroxide have yielded mercury oxide instead. Being

Heyden Power Station - Misplaced Pages Continue

4158-464: Is still important as the fuel source for diesel engine power plants used especially in isolated communities not interconnected to a grid. Liquid fuels may also be used by gas turbine power plants, especially for peaking or emergency service. Of the three fossil fuel sources, oil has the advantages of easier transportation and handling than solid coal, and easier on-site storage than natural gas. Combined heat and power (CHP), also known as cogeneration ,

4257-502: Is still unknown as to which kinds of particulate matter pose the most harm, which makes it difficult to come up with adequate legislation for regulating particulate matter. There are several methods of helping to reduce the particulate matter emissions from coal-fired plants. Roughly 80% of the ash falls into an ash hopper, but the rest of the ash then gets carried into the atmosphere to become coal-fly ash. Methods of reducing these emissions of particulate matter include: The baghouse has

4356-459: Is the " nameplate capacity " or the maximum allowed output of the plant, " capacity factor " or "load factor" is a measure of the amount of power that a plant produces compared with the amount it would produce if operated at its rated capacity nonstop, heat rate is thermal energy in/electrical energy out, emission intensity (also called emission factor ) is the CO 2 emitted per unit of heat generated for

4455-536: Is the use of a thermal power station to provide both electric power and heat (the latter being used, for example, for district heating purposes). This technology is practiced not only for domestic heating (low temperature) but also for industrial process heat, which is often high temperature heat. Calculations show that Combined Heat and Power District Heating (CHPDH) is the cheapest method in reducing (but not eliminating) carbon emissions, if conventional fossil fuels remain to be burned. Thermal power plants are one of

4554-484: Is toxic to the nervous system , immune system and kidneys of humans and other animals; mercury poisoning can result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury ) either directly or through mechanisms of biomagnification . Mercury is used in thermometers , barometers , manometers , sphygmomanometers , float valves , mercury switches , mercury relays , fluorescent lamps and other devices, although concerns about

4653-573: Is used as the ligand). Mercury(I) chloride , a colorless solid also known as calomel , is really the compound with the formula Hg 2 Cl 2 , with the connectivity Cl-Hg-Hg-Cl. It reacts with chlorine to give mercury(II) chloride , which resists further oxidation. Mercury(I) hydride , a colorless gas, has the formula HgH, containing no Hg-Hg bond; however, the gas has only ever been observed as isolated molecules. Indicative of its tendency to bond to itself, mercury forms mercury polycations , which consist of linear chains of mercury centers, capped with

4752-518: Is used in some liquid-in-glass thermometers , especially those used to measure high temperatures. A still increasing amount is used as gaseous mercury in fluorescent lamps , while most of the other applications are slowly being phased out due to health and safety regulations. In some applications, mercury is replaced with less toxic but considerably more expensive Galinstan alloy . Mercury and its compounds have been used in medicine, although they are much less common today than they once were, now that

4851-465: Is what remains after the coal has been combusted, so it consists of the incombustible materials that are found in the coal. The size and chemical composition of these particles affects the impacts on human health. Currently coarse (diameter greater than 2.5 μm) and fine (diameter between 0.1 μm and 2.5 μm) particles are regulated, but ultrafine particles (diameter less than 0.1 μm) are currently unregulated, yet they pose many dangers. Unfortunately much

4950-810: The European Environment Agency (EEA) documented fuel-dependent emission factors based on actual emissions from power plants in the European Union . Electricity generation using carbon-based fuels is responsible for a large fraction of carbon dioxide (CO 2 ) emissions worldwide and for 34% of U.S. man-made carbon dioxide emissions in 2010. In the U.S. 70% of electricity is generated by combustion of fossil fuels. Coal contains more carbon than oil or natural gas fossil fuels, resulting in greater volumes of carbon dioxide emissions per unit of electricity generated. In 2010, coal contributed about 81% of CO 2 emissions from generation and contributed about 45% of

5049-580: The First Matter from which all metals were formed. They believed that different metals could be produced by varying the quality and quantity of sulfur contained within the mercury. The purest of these was gold, and mercury was called for in attempts at the transmutation of base (or impure) metals into gold, which was the goal of many alchemists. The mines in Almadén (Spain), Monte Amiata (Italy), and Idrija (now Slovenia) dominated mercury production from

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5148-471: The Neolithic Age . In China and Tibet , mercury use was thought to prolong life, heal fractures, and maintain generally good health, although it is now known that exposure to mercury vapor leads to serious adverse health effects. The first emperor of a unified China, Qín Shǐ Huáng Dì —allegedly buried in a tomb that contained rivers of flowing mercury on a model of the land he ruled, representative of

5247-551: The Rankine cycle of the HRSG. The turbines are fueled either with natural gas or fuel oil. Diesel engine generator sets are often used for prime power in communities not connected to a widespread power grid. Emergency (standby) power systems may use reciprocating internal combustion engines operated by fuel oil or natural gas. Standby generators may serve as emergency power for a factory or data center, or may also be operated in parallel with

5346-540: The air is converted successively into thermal energy , mechanical energy and, finally, electrical energy . Each fossil fuel power plant is a complex, custom-designed system. Multiple generating units may be built at a single site for more efficient use of land , natural resources and labor . Most thermal power stations in the world use fossil fuel, outnumbering nuclear , geothermal , biomass , or concentrated solar power plants. The second law of thermodynamics states that any closed-loop cycle can only convert

5445-436: The greenhouse gas carbon dioxide within the atmosphere will "very likely" lead to higher average temperatures on a global scale ( global warming ). Concerns regarding the potential for such warming to change the global climate prompted IPCC recommendations calling for large cuts to CO 2 emissions worldwide. Emissions can be reduced with higher combustion temperatures, yielding more efficient production of electricity within

5544-546: The 1650s. Fahrenheit's mercury thermometer was based on an earlier design that used alcohol rather than mercury; the mercury thermometer was significantly more accurate than those using alcohol. From the early 21st century onwards, the use of mercury thermometers has been declining, and mercury-containing instruments have been banned in many jurisdictions following the 1998 Protocol on Heavy Metals . Modern alternatives to mercury thermometers include resistance thermometers , thermocouples , and thermistor sensors that output to

5643-485: The 1960s onward, the majority of industrial plants moved away from mercury cell processes towards diaphragm cell technologies to produce chlorine, though 11% of the chlorine made in the United States was still produced with the mercury cell method as of 2005. Thermometers containing mercury were invented in the early 18th century by Daniel Gabriel Fahrenheit , though earlier attempts at making temperature-measuring instruments filled with quicksilver had been described in

5742-550: The 2010s, in many countries plants designed for baseload supply are being operated as dispatchable generation to balance increasing generation by variable renewable energy . By-products of fossil fuel power plant operation must be considered in their design and operation. Flue gas from combustion of the fossil fuels contains carbon dioxide and water vapor, as well as pollutants such as nitrogen oxides (NO x ), sulfur oxides (SO x ), and, for coal-fired plants, mercury , traces of other metals, and fly ash . Usually all of

5841-399: The United States and Mexico, which once produced a large proportion of the world supply, have now been completely mined out or, in the case of Slovenia ( Idrija ) and Spain ( Almadén ), shut down due to the fall of the price of mercury. Nevada 's McDermitt Mine, the last mercury mine in the United States, closed in 1992. The price of mercury has been highly volatile over the years and in 2006

5940-405: The aircraft. Mercury embrittlement is the most common type of liquid metal embrittlement, as mercury is a natural component of some hydrocarbon reservoirs and will come into contact with petroleum processing equipment under normal conditions. There are seven stable isotopes of mercury, with Hg being the most abundant (29.86%). The longest-lived radioisotopes are Hg with

6039-401: The carbon dioxide and some of the other pollution is discharged to the air. Solid waste ash from coal-fired boilers must also be removed. Fossil fueled power stations are major emitters of carbon dioxide (CO 2 ), a greenhouse gas which is a major contributor to global warming . The results of a recent study show that the net income available to shareholders of large companies could see

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6138-466: The case of coal fly ash from non-combustible substances in the fuel. Waste heat from the condenser is transferred either to the air, or sometimes to a cooling pond, lake or river. One type of fossil fuel power plant uses a gas turbine in conjunction with a heat recovery steam generator (HRSG). It is referred to as a combined cycle power plant because it combines the Brayton cycle of the gas turbine with

6237-464: The crustal mass, mercury ores can be extraordinarily concentrated considering the element's abundance in ordinary rock. The richest mercury ores contain up to 2.5% mercury by mass, and even the leanest concentrated deposits are at least 0.1% mercury (12,000 times average crustal abundance). It is found either as a native metal (rare) or in cinnabar , metacinnabar , sphalerite , corderoite , livingstonite and other minerals , with cinnabar (HgS) being

6336-423: The cycle. As of 2019 the price of emitting CO 2 to the atmosphere is much lower than the cost of adding carbon capture and storage (CCS) to fossil fuel power stations, so owners have not done so. The CO 2 emissions from a fossil fuel power station can be estimated with the following formula: CO 2 emissions = capacity x capacity factor x heat rate x emission intensity x time where "capacity"

6435-514: The daily base electricity demand. Between January and February 2021 the power plant had to be restarted six times, even though it had been officially shut down because of the Energiewende . In early April the plant was reclassified from shut down to "spinning power." From the end of August 2022, the hard-coal-fired power plant will go from mere grid reserve back into continuous operation in order to save natural gas . Heyden has been fitted with

6534-531: The dimeric cation, Hg 2 . Stable derivatives include the chloride and nitrate . In aqueous solution of a mercury(I) salt, slight disproportion of Hg 2 into Hg and Hg results in >0.5% of dissolved mercury existing as Hg . In these solutions, complexation of the Hg with addition of ligands such as cyanide causes disproportionation to go to completion, with all Hg 2 precipitating as elemental mercury and insoluble mercury(II) compounds (e.g. mercury(II) cyanide if cyanide

6633-510: The electricity generated in the United States. In 2000, the carbon intensity (CO 2 emissions) of U.S. coal thermal combustion was 2249 lbs/MWh (1,029 kg/MWh) while the carbon intensity of U.S. oil thermal generation was 1672 lb/MWh (758 kg/MWh or 211 kg/ GJ ) and the carbon intensity of U.S. natural gas thermal production was 1135 lb/MWh (515 kg/MWh or 143 kg/GJ). The Intergovernmental Panel on Climate Change ( IPCC ) reports that increased quantities of

6732-444: The element's toxicity have led to the phasing out of such mercury-containing instruments. It remains in use in scientific research applications and in amalgam for dental restoration in some locales. It is also used in fluorescent lighting . Electricity passed through mercury vapor in a fluorescent lamp produces short-wave ultraviolet light , which then causes the phosphor in the tube to fluoresce , making visible light. Mercury

6831-431: The first central stations used reciprocating steam engines to drive generators. As the size of the electrical load to be served grew, reciprocating units became too large and cumbersome to install economically. The steam turbine rapidly displaced all reciprocating engines in central station service. Coal is the most abundant fossil fuel on the planet, and widely used as the source of energy in thermal power stations and

6930-539: The form of one of its common ores, cinnabar, is used in various traditional medicines, especially in traditional Chinese medicine . Review of its safety has found that cinnabar can lead to significant mercury intoxication when heated, consumed in overdose , or taken long term, and can have adverse effects at therapeutic doses, though effects from therapeutic doses are typically reversible. Although this form of mercury appears to be less toxic than other forms, its use in traditional Chinese medicine has not yet been justified, as

7029-471: The formula HgR 2 , which are often volatile, or HgRX, which are often solids, where R is aryl or alkyl and X is usually halide or acetate. Methylmercury , a generic term for compounds with the formula CH 3 HgX, is a dangerous family of compounds that are often found in polluted water. They arise by a process known as biomethylation . Mercury is used primarily for the manufacture of industrial chemicals or for electrical and electronic applications. It

7128-568: The fuel system maintenance requirements. Spark-ignition internal combustion engines operating on gasoline (petrol), propane , or LPG are commonly used as portable temporary power sources for construction work, emergency power, or recreational uses. Reciprocating external combustion engines such as the Stirling engine can be run on a variety of fossil fuels, as well as renewable fuels or industrial waste heat. Installations of Stirling engines for power production are relatively uncommon. Historically,

7227-539: The furnace temperature improves the efficiency but complicates the design, primarily by the selection of alloys used for construction, making the furnace more expensive. The waste heat cannot be converted into mechanical energy without a cooler cooling system. However, it may be used in cogeneration plants to heat buildings, produce hot water, or to heat materials on an industrial scale, such as in some oil refineries , plants, and chemical synthesis plants. Typical thermal efficiency for utility-scale electrical generators

7326-700: The historic Almaden Quicksilver Mine and created a county park on the site, after conducting extensive safety and environmental analysis of the property. All known mercury compounds exhibit one of two positive oxidation states: I and II. Experiments have failed to unequivocally demonstrate any higher oxidation states: both the claimed 1976 electrosynthesis of an unstable Hg(III) species and 2007 cryogenic isolation of HgF 4 have disputed interpretations and remain difficult (if not impossible) to reproduce. Unlike its lighter neighbors, cadmium and zinc, mercury usually forms simple stable compounds with metal-metal bonds. Most mercury(I) compounds are diamagnetic and feature

7425-460: The hot exhaust gases from the gas turbines are used to generate steam to power a steam turbine. The pollution levels of such plants are drastically lower than those of "classic" coal power plants. Particulate matter from coal-fired plants can be harmful and have negative health impacts. Studies have shown that exposure to particulate matter is related to an increase of respiratory and cardiac mortality. Particulate matter can irritate small airways in

7524-483: The largest use of mercury in the late 20th century was in the mercury cell process (also called the Castner-Kellner process ) where metallic sodium is formed as an amalgam at a cathode made from mercury; this sodium is then reacted with water to produce sodium hydroxide. Many of the industrial mercury releases of the 20th century came from this process, although modern plants claim to be safe in this regard. From

7623-436: The local utility system to reduce peak power demand charge from the utility. Diesel engines can produce strong torque at relatively low rotational speeds, which is generally desirable when driving an alternator , but diesel fuel in long-term storage can be subject to problems resulting from water accumulation and chemical decomposition . Rarely used generator sets may correspondingly be installed as natural gas or LPG to minimize

7722-428: The lungs, which can lead to increased problems with asthma, chronic bronchitis, airway obstruction, and gas exchange. There are different types of particulate matter, depending on the chemical composition and size. The dominant form of particulate matter from coal-fired plants is coal fly ash , but secondary sulfate and nitrate also comprise a major portion of the particulate matter from coal-fired plants. Coal fly ash

7821-476: The main artificial sources of producing toxic gases and particulate matter . Fossil fuel power plants cause the emission of pollutants such as NO x , SO x , CO 2 , CO, PM, organic gases and polycyclic aromatic hydrocarbons. World organizations and international agencies, like the IEA, are concerned about the environmental impact of burning fossil fuels , and coal in particular. The combustion of coal contributes

7920-533: The mercury for the colonies. Mercury deposits were discovered in the New World, and more than 100,000 tons of mercury were mined from the region of Huancavelica , Peru, over the course of three centuries following the discovery of deposits there in 1563. The patio process and later pan amalgamation process continued to create great demand for mercury to treat silver ores until the late 19th century. Former mines in Italy,

8019-564: The mercury required for CFL bulb manufacture. Environmental dangers have been a concern, particularly in the southern cities of Foshan and Guangzhou , and in Guizhou province in the southwest. Abandoned mercury mine processing sites often contain very hazardous waste piles of roasted cinnabar calcines . Water run-off from such sites is a recognized source of ecological damage. Former mercury mines may be suited for constructive re-use; for example, in 1976 Santa Clara County, California purchased

8118-602: The mining of cinnabar and refining for mercury are hazardous and historic causes of mercury poisoning. In China, prison labor was used by a private mining company as recently as the 1950s to develop new cinnabar mines. Thousands of prisoners were used by the Luo Xi mining company to establish new tunnels. Worker health in functioning mines is at high risk. A newspaper claimed that an unidentified European Union directive calling for energy-efficient lightbulbs to be made mandatory by 2012 encouraged China to re-open cinnabar mines to obtain

8217-496: The modern chemical symbol for mercury. It is an abbreviation of hydrargyrum , a romanized form of the ancient Greek name for mercury, ὑδράργυρος ( hydrargyros ). Hydrargyros is a Greek compound word meaning ' water-silver ' , from ὑδρ - ( hydr -), the root of ὕδωρ ( hydor ) ' water ' , and ἄργυρος ( argyros ) ' silver ' . Like the English name quicksilver ( ' living-silver ' ), this name

8316-667: The most common ore. Mercury ores often occur in hot springs or other volcanic regions. Beginning in 1558, with the invention of the patio process to extract silver from ore using mercury, mercury became an essential resource in the economy of Spain and its American colonies. Mercury was used to extract silver from the lucrative mines in New Spain and Peru . Initially, the Spanish Crown's mines in Almadén in Southern Spain supplied all

8415-488: The most to acid rain and air pollution , and has been connected with global warming . Due to the chemical composition of coal there are difficulties in removing impurities from the solid fuel prior to its combustion. Modern day coal power plants pollute less than older designs due to new " scrubber " technologies that filter the exhaust air in smoke stacks. However, emission levels of various pollutants are still on average several times greater than natural gas power plants and

8514-457: The opening of the mine in Almadén 2500 years ago, until new deposits were found at the end of the 19th century. Mercury is an extremely rare element in Earth's crust ; it has an average crustal abundance by mass of only 0.08 parts per million (ppm) and is the 66th most abundant element in the Earth's crust. Because it does not blend geochemically with those elements that constitute the majority of

8613-607: The particular wastestream in the plant. These include dry ash handling, closed-loop ash recycling, chemical precipitation, biological treatment (such as an activated sludge process), membrane systems, and evaporation-crystallization systems. In 2015 EPA published a regulation pursuant to the Clean Water Act that requires US power plants to use one or more of these technologies. Technological advancements in ion exchange membranes and electrodialysis systems has enabled high efficiency treatment of flue-gas desulfurization wastewater to meet

8712-463: The planet became one of the alchemical symbols for the metal, and Mercury became an alternative name for the metal. Mercury is the only metal for which the alchemical planetary name survives, as it was decided it was preferable to quicksilver as a chemical name. Mercury was found in Egyptian tombs that date from 1500 BC; cinnabar , the most common natural source of mercury, has been in use since

8811-483: The rivers of China—was reportedly killed by drinking a mercury and powdered jade mixture formulated by Qin alchemists intended as an elixir of immortality. Khumarawayh ibn Ahmad ibn Tulun , the second Tulunid ruler of Egypt (r. 884–896), known for his extravagance and profligacy , reportedly built a basin filled with mercury, on which he would lie on top of air-filled cushions and be rocked to sleep. In November 2014 "large quantities" of mercury were discovered in

8910-423: The safety and effectiveness" of the mercury ingredients in these products. Chlorine is produced from sodium chloride (common salt, NaCl) using electrolysis to separate metallic sodium from chlorine gas. Usually salt is dissolved in water to produce a brine. By-products of any such chloralkali process are hydrogen (H 2 ) and sodium hydroxide (NaOH), which is commonly called caustic soda or lye . By far

9009-481: The same thermodynamic limits as they are not heat engines. The efficiency of a fossil fuel plant may be expressed as its heat rate , expressed in BTU/kilowatthour or megajoules/kilowatthour. In a steam turbine power plant, fuel is burned in a furnace and the hot gasses flow through a boiler. Water is converted to steam in the boiler; additional heating stages may be included to superheat the steam. The hot steam

9108-530: The scrubbers transfer the captured pollutants to wastewater, which still requires treatment in order to avoid pollution of receiving water bodies. In these modern designs, pollution from coal-fired power plants comes from the emission of gases such as carbon dioxide, nitrogen oxides , and sulfur dioxide into the air, as well a significant volume of wastewater which may contain lead , mercury , cadmium and chromium , as well as arsenic , selenium and nitrogen compounds ( nitrates and nitrites ). Acid rain

9207-409: The symptoms of its toxicity were confused with those of the syphilis it was believed to treat. It is also used as a disinfectant. Blue mass , a pill or syrup in which mercury is the main ingredient, was prescribed throughout the 19th century for numerous conditions including constipation, depression, child-bearing and toothaches. In the early 20th century, mercury was administered to children yearly as

9306-418: The therapeutic basis for the use of cinnabar is not clear. Mercury(I) chloride (also known as calomel or mercurous chloride) has been used in traditional medicine as a diuretic , topical disinfectant , and laxative . Mercury(II) chloride (also known as mercuric chloride or corrosive sublimate) was once used to treat syphilis (along with other mercury compounds), although it is so toxic that sometimes

9405-415: The toxic effects of mercury and its compounds are more widely understood. An example of the early therapeutic application of mercury was published in 1787 by James Lind . The first edition of The Merck Manuals (1899) featured many then-medically relevant mercuric compounds, such as mercury-ammonium chloride , yellow mercury proto-iodide , calomel , and mercuric chloride , among others. Mercury in

9504-531: The updated EPA discharge limits. Coal is a sedimentary rock formed primarily from accumulated plant matter, and it includes many inorganic minerals and elements which were deposited along with organic material during its formation. As the rest of the Earth's crust , coal also contains low levels of uranium , thorium , and other naturally occurring radioactive isotopes whose release into the environment leads to radioactive contamination . While these substances are present as very small trace impurities, enough coal

9603-400: Was $ 650 per 76-pound (34.46 kg) flask . Mercury is extracted by heating cinnabar in a current of air and condensing the vapor. The equation for this extraction is: In 2020, China was the top producer of mercury, providing 88% of the world output (2200 out of 2500 tonnes), followed by Tajikistan (178 t), Russia (50 t) and Mexico (32 t). Because of the high toxicity of mercury, both

9702-496: Was due to mercury's liquid and shiny properties. The modern English name mercury comes from the planet Mercury . In medieval alchemy , the seven known metals—quicksilver, gold , silver , copper , iron , lead , and tin —were associated with the seven planets. Quicksilver was associated with the fastest planet, which had been named after the Roman god Mercury , who was associated with speed and mobility. The astrological symbol for

9801-455: Was found in the late 20th century or early 21st century, such as the US and UK. Sometimes coal-fired steam plants are refitted to use natural gas to reduce net carbon dioxide emissions. Oil-fuelled plants may be converted to natural gas to lower operating cost. Heavy fuel oil was once a significant source of energy for electric power generation. After oil price increases of the 1970s, oil was displaced by coal and later natural gas. Distillate oil

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