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70-517: The industrial island is the endpoint of the undersea pipeline that transports natural gas from the Snøhvit natural gas fields in the Barents Sea . The gas goes through the 168-kilometre (104 mi) long pipeline to the processing plant Hammerfest LNG on Melkøya where 18 million cubic meters per day is converted into liquefied natural gas . The plant opened in 2007 and is operated by Equinor . After

140-702: A 34,000 t/a plant at Yanbu to produce acetic acid by ethane oxidation. The economic viability of this process may rely on the low cost of ethane near Saudi oil fields, and it may not be competitive with methanol carbonylation elsewhere in the world. Ethane can be used as a refrigerant in cryogenic refrigeration systems. On a much smaller scale, in scientific research, liquid ethane is used to vitrify water-rich samples for cryo-electron microscopy . A thin film of water quickly immersed in liquid ethane at −150 °C or colder freezes too quickly for water to crystallize. Slower freezing methods can generate cubic ice crystals, which can disrupt soft structures by damaging

210-476: A density 0.5539 times that of air (0.678 kg per standard cubic meter). In the early 1800s, natural gas became known as "natural" to distinguish it from the dominant gas fuel at the time, coal gas . Unlike coal gas, which is manufactured by heating coal, natural gas can be extracted from the ground in its native gaseous form. When the use of natural gas overtook the use of coal gas in English speaking countries in

280-552: A feedstock for other commodity chemicals. Oxidative chlorination of ethane has long appeared to be a potentially more economical route to vinyl chloride than ethylene chlorination. Many patent exist on this theme, but poor selectivity for vinyl chloride and corrosive reaction conditions have discouraged the commercialization of most of them. Presently, INEOS operates a 1000 t/a ( tonnes per annum ) ethane-to-vinyl chloride pilot plant at Wilhelmshaven in Germany . SABIC operates

350-427: A fire closed the plant in 2020, it re-opened in 2022. Liquefied natural gas is then exported from Melkøya to world markets by a LNG gas carrier or tanker . The island was previously used for farming, and rental houses for seasonal fishermen were also built on the island. In 2001 and 2002, major archaeological investigations on Melkøya were undertaken before Statoil's development of the island began. The development of

420-477: A major source of natural gas in the United States and Canada. Because of increased shale gas production the United States was in 2014 the number one natural gas producer in the world. The production of shale gas in the United States has been described as a "shale gas revolution" and as "one of the landmark events in the 21st century." Following the increased production in the United States, shale gas exploration

490-493: A primordial component of the solar nebula from which the sun and planets are believed to have formed. In 2006, Dale Cruikshank of NASA/Ames Research Center (a New Horizons co-investigator) and his colleagues announced the spectroscopic discovery of ethane on Pluto 's surface. The reactions of ethane involve chiefly free radical reactions . Ethane can react with the halogens , especially chlorine and bromine , by free-radical halogenation . This reaction proceeds through

560-538: A synthetic crude that can be further refined into finished products, while MTG can produce synthetic gasoline from natural gas. STG+ can produce drop-in gasoline, diesel, jet fuel and aromatic chemicals directly from natural gas via a single-loop process. In 2011, Royal Dutch Shell's 140,000 barrels (22,000 m ) per day F–T plant went into operation in Qatar . Natural gas can be "associated" (found in oil fields ), or "non-associated" (isolated in natural gas fields ), and

630-715: Is a plastic crystal , crystallizing in the cubic system. In this form, the positions of the hydrogen atoms are not fixed; the molecules may rotate freely around the long axis. Cooling this ethane below ca. 89.9 K (−183.2 °C; −297.8 °F) changes it to monoclinic metastable ethane II ( space group P 21/n). Ethane is only very sparingly soluble in water. The bond parameters of ethane have been measured to high precision by microwave spectroscopy and electron diffraction: r C−C = 1.528(3) Å, r C−H = 1.088(5) Å, and ∠CCH = 111.6(5)° by microwave and r C−C = 1.524(3) Å, r C−H = 1.089(5) Å, and ∠CCH = 111.9(5)° by electron diffraction (the numbers in parentheses represents

700-493: Is a flammable gaseous fuel made by the destructive distillation of coal . It contains a variety of calorific gases including hydrogen , carbon monoxide , methane , and other volatile hydrocarbons , together with small quantities of non-calorific gases such as carbon dioxide and nitrogen , and was used in a similar way to natural gas. This is a historical technology and is not usually economically competitive with other sources of fuel gas today. Most town "gashouses" located in

770-408: Is a naturally occurring organic chemical compound with chemical formula C 2 H 6 . At standard temperature and pressure , ethane is a colorless, odorless gas . Like many hydrocarbons , ethane is isolated on an industrial scale from natural gas and as a petrochemical by-product of petroleum refining . Its chief use is as feedstock for ethylene production. The ethyl group

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840-458: Is a schematic block flow diagram of a typical natural gas processing plant. It shows the various unit processes used to convert raw natural gas into sales gas pipelined to the end user markets. The block flow diagram also shows how processing of the raw natural gas yields byproduct sulfur, byproduct ethane, and natural gas liquids (NGL) propane, butanes and natural gasoline (denoted as pentanes +). As of mid-2020, natural gas production in

910-447: Is a significant product: Such oxidative dehydrogenation reactions are relevant to the production of ethylene . After methane , ethane is the second-largest component of natural gas . Natural gas from different gas fields varies in ethane content from less than 1% to more than 6% by volume. Prior to the 1960s, ethane and larger molecules were typically not separated from the methane component of natural gas, but simply burnt along with

980-399: Is also found in coal beds (as coalbed methane ). It sometimes contains a significant amount of ethane , propane , butane , and pentane —heavier hydrocarbons removed for commercial use prior to the methane being sold as a consumer fuel or chemical plant feedstock. Non-hydrocarbons such as carbon dioxide , nitrogen , helium (rarely), and hydrogen sulfide must also be removed before

1050-616: Is beginning in countries such as Poland, China, and South Africa. Chinese geologists have identified the Sichuan Basin as a promising target for shale gas drilling, because of the similarity of shales to those that have proven productive in the United States. Production from the Wei-201 well is between 10,000 and 20,000 m per day. In late 2020, China National Petroleum Corporation claimed daily production of 20 million cubic meters of gas from its Changning-Weiyuan demonstration zone. Town gas

1120-556: Is colorless and odorless, and the second largest greenhouse gas contributor to global climate change after carbon dioxide. Because natural gas is odorless, odorizers such as mercaptan (which smells like rotten eggs ) are commonly added to it for safety so that leaks can be readily detected. Natural gas is a fossil fuel that is formed when layers of organic matter (primarily marine microorganisms) decompose under anaerobic conditions and are subjected to intense heat and pressure underground over millions of years. The energy that

1190-537: Is estimated to have 51,000 cubic kilometers (12,000 cu mi) of natural gas and 50 billion barrels (7.9 billion cubic meters) of natural gas condensates . Because natural gas is not a pure product, as the reservoir pressure drops when non-associated gas is extracted from a field under supercritical (pressure/temperature) conditions, the higher molecular weight components may partially condense upon isothermic depressurizing—an effect called retrograde condensation . The liquid thus formed may get trapped as

1260-493: Is formally, although rarely practically, derived from ethane. Ethane was first synthesised in 1834 by Michael Faraday , applying electrolysis of a potassium acetate solution. He mistook the hydrocarbon product of this reaction for methane and did not investigate it further. The process is now called Kolbe electrolysis : During the period 1847–1849, in an effort to vindicate the radical theory of organic chemistry , Hermann Kolbe and Edward Frankland produced ethane by

1330-694: Is heated and compressed deep underground. Methanogenic organisms produce methane from a variety of sources, principally carbon dioxide. During petroleum production, natural gas is sometimes flared rather than being collected and used. Before natural gas can be burned as a fuel or used in manufacturing processes, it almost always has to be processed to remove impurities such as water. The byproducts of this processing include ethane , propane , butanes , pentanes , and higher molecular weight hydrocarbons. Hydrogen sulfide (which may be converted into pure sulfur ), carbon dioxide , water vapor , and sometimes helium and nitrogen must also be removed. Natural gas

1400-403: Is natural gas produced from shale . Because shale's matrix permeability is too low to allow gas to flow in economical quantities, shale gas wells depend on fractures to allow the gas to flow. Early shale gas wells depended on natural fractures through which gas flowed; almost all shale gas wells today require fractures artificially created by hydraulic fracturing . Since 2000, shale gas has become

1470-406: Is often stored underground [references about geological storage needed]inside depleted gas reservoirs from previous gas wells, salt domes , or in tanks as liquefied natural gas. The gas is injected in a time of low demand and extracted when demand picks up. Storage nearby end users helps to meet volatile demands, but such storage may not always be practicable. With 15 countries accounting for 84% of

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1540-452: Is preparing to export natural gas. Floating liquefied natural gas (FLNG) is an innovative technology designed to enable the development of offshore gas resources that would otherwise remain untapped due to environmental or economic factors which currently make them impractical to develop via a land-based LNG operation. FLNG technology also provides a number of environmental and economic advantages: Many gas and oil companies are considering

1610-545: Is primarily dependent on proximity to markets (pipelines), and regulatory restrictions. Natural gas can be indirectly exported through the absorption in other physical output. The expansion of shale gas production in the US has caused prices to drop relative to other countries. This has caused a boom in energy intensive manufacturing sector exports, whereby the average dollar unit of US manufacturing exports has almost tripled its energy content between 1996 and 2012. A "master gas system"

1680-429: Is primarily used in the northern hemisphere. North America and Europe are major consumers. Often well head gases require removal of various hydrocarbon molecules contained within the gas. Some of these gases include heptane , pentane , propane and other hydrocarbons with molecular weights above methane ( CH 4 ). The natural gas transmission lines extend to the natural gas processing plant or unit which removes

1750-709: Is sometimes informally referred to simply as "gas", especially when it is being compared to other energy sources, such as oil, coal or renewables. However, it is not to be confused with gasoline , which is also shortened in colloquial usage to "gas", especially in North America. Natural gas is measured in standard cubic meters or standard cubic feet . The density compared to air ranges from 0.58 (16.8 g/mole, 0.71 kg per standard cubic meter) to as high as 0.79 (22.9 g/mole, 0.97 kg per scm), but generally less than 0.64 (18.5 g/mole, 0.78 kg per scm). For comparison, pure methane (16.0425 g/mole) has

1820-604: Is traded on a "dry gas" basis and is required to be commercially free from objectionable odours, materials, and dust or other solid or liquid matter, waxes, gums and gum forming constituents, which might damage or adversely affect operation of equipment downstream of the custody transfer point. LNG carrier ships transport liquefied natural gas (LNG) across oceans, while tank trucks can carry LNG or compressed natural gas (CNG) over shorter distances. Sea transport using CNG carrier ships that are now under development may be competitive with LNG transport in specific conditions. Gas

1890-409: Is transported at high pressure, typically above 200 bars (20,000 kPa; 2,900 psi). Compressors and decompression equipment are less capital intensive and may be economical in smaller unit sizes than liquefaction/regasification plants. Natural gas trucks and carriers may transport natural gas directly to end-users, or to distribution points such as pipelines. In the past, the natural gas which

1960-416: Is turned into liquid at a liquefaction plant, and is returned to gas form at regasification plant at the terminal . Shipborne regasification equipment is also used. LNG is the preferred form for long distance, high volume transportation of natural gas, whereas pipeline is preferred for transport for distances up to 4,000 km (2,500 mi) over land and approximately half that distance offshore. CNG

2030-434: The propane and heavier hydrocarbons. The chief use of ethane is the production of ethylene (ethene) by steam cracking . Steam cracking of ethane is fairly selective for ethylene, while the steam cracking of heavier hydrocarbons yields a product mixture poorer in ethylene and richer in heavier alkenes (olefins) , such as propene (propylene) and butadiene , and in aromatic hydrocarbons . Ehane has been investigated as

2100-427: The supply chain can result in natural gas having a similar carbon footprint to other fossil fuels overall. Natural gas can be found in underground geological formations , often alongside other fossil fuels like coal and oil (petroleum). Most natural gas has been created through either biogenic or thermogenic processes. Thermogenic gas takes a much longer period of time to form and is created when organic matter

2170-548: The 19th century, natural gas was primarily obtained as a by-product of producing oil . The small, light gas carbon chains came out of solution as the extracted fluids underwent pressure reduction from the reservoir to the surface, similar to uncapping a soft drink bottle where the carbon dioxide effervesces . The gas was often viewed as a by-product, a hazard, and a disposal problem in active oil fields. The large volumes produced could not be used until relatively expensive pipeline and storage facilities were constructed to deliver

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2240-406: The 20th century, it was increasingly referred to as simply "gas." In order to highlight its role in exacerbating the climate crisis , however, many organizations have criticized the continued use of the word "natural" in referring to the gas. These advocates prefer the term "fossil gas" or "methane gas" as better conveying to the public its climate threat. A 2020 study of Americans' perceptions of

2310-413: The U.S. has arrested the decline by half. Although ethane is a greenhouse gas , it is much less abundant than methane, has a lifetime of only a few months compared to over a decade, and is also less efficient at absorbing radiation relative to mass. In fact, ethane's global warming potential largely results from its conversion in the atmosphere to methane. It has been detected as a trace component in

2380-432: The US had peaked three times, with current levels exceeding both previous peaks. It reached 24.1 trillion cubic feet per year in 1973, followed by a decline, and reached 24.5 trillion cubic feet in 2001. After a brief drop, withdrawals increased nearly every year since 2006 (owing to the shale gas boom ), with 2017 production at 33.4 trillion cubic feet and 2019 production at 40.7 trillion cubic feet. After

2450-427: The US, over one-third of households (>40 million homes) cook with gas. Natural gas dispensed in a residential setting can generate temperatures in excess of 1,100 °C (2,000 °F) making it a powerful domestic cooking and heating fuel. Stanford scientists estimated that gas stoves emit 0.8–1.3% of the gas they use as unburned methane and that total U.S. stove emissions are 28.1 gigagrams of methane. In much of

2520-515: The United States begins with localized use. In the seventeenth century, French missionaries witnessed the American Indians setting fire to natural gas seeps around lake Erie, and scattered observations of these seeps were made by European-descended settlers throughout the eastern seaboard through the 1700s. In 1821, William Hart dug the first commercial natural gas well in the United States at Fredonia, New York , United States, which led in 1858 to

2590-445: The atmospheres of all four giant planets , and in the atmosphere of Saturn 's moon Titan . Atmospheric ethane results from the Sun's photochemical action on methane gas, also present in these atmospheres: ultraviolet photons of shorter wavelengths than 160 nm can photo-dissociate the methane molecule into a methyl radical and a hydrogen atom. When two methyl radicals recombine,

2660-697: The bottoms of the gashouse ovens was often used for roofing and other waterproofing purposes, and when mixed with sand and gravel was used for paving streets. Huge quantities of natural gas (primarily methane) exist in the form of clathrates under sediment on offshore continental shelves and on land in arctic regions that experience permafrost , such as those in Siberia . Hydrates require a combination of high pressure and low temperature to form. In 2013, Japan Oil, Gas and Metals National Corporation (JOGMEC) announced that they had recovered commercially relevant quantities of natural gas from methane hydrate. The image below

2730-654: The decayed organisms originally obtained from the sun via photosynthesis is stored as chemical energy within the molecules of methane and other hydrocarbons. Natural gas can be burned for heating, cooking, and electricity generation . Consisting mainly of methane, natural gas is rarely used as a chemical feedstock . The extraction and consumption of natural gas is a major industry. When burned for heat or electricity , natural gas emits fewer toxic air pollutants, less carbon dioxide, and almost no particulate matter compared to other fossil and biomass fuels. However, gas venting and unintended fugitive emissions throughout

2800-567: The developed world it is supplied through pipes to homes, where it is used for many purposes including ranges and ovens, heating / cooling , outdoor and portable grills , and central heating . Heaters in homes and other buildings may include boilers, furnaces , and water heaters . Both North America and Europe are major consumers of natural gas. Ethane 544.0 kg/m (liquid at -88,5 °C) 206 kg/m (at critical point 305.322 K) Ethane ( US : / ˈ ɛ θ eɪ n / ETH -ayn , UK : / ˈ iː -/ EE - )

2870-446: The eastern US in the late 19th and early 20th centuries were simple by-product coke ovens that heated bituminous coal in air-tight chambers. The gas driven off from the coal was collected and distributed through networks of pipes to residences and other buildings where it was used for cooking and lighting. (Gas heating did not come into widespread use until the last half of the 20th century.) The coal tar (or asphalt ) that collected in

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2940-446: The economic and environmental benefits of floating liquefied natural gas (FLNG). There are currently projects underway to construct five FLNG facilities. Petronas is close to completion on their FLNG-1 at Daewoo Shipbuilding and Marine Engineering and are underway on their FLNG-2 project at Samsung Heavy Industries . Shell Prelude is due to start production 2017. The Browse LNG project will commence FEED in 2019. Natural gas

3010-486: The formation of the Fredonia Gas Light Company . Further such ventures followed near wells in other states, until technological innovations allowed the growth of major long distance pipelines from the 1920s onward. By 2009, 66,000 km (16,000 cu mi) (or 8%) had been used out of the total 850,000 km (200,000 cu mi) of estimated remaining recoverable reserves of natural gas. In

3080-461: The fuel found that, across political identifications, the term "methane gas" led to better estimates of its harms and risks. Natural gas can come out of the ground and cause a long-burning fire. In ancient Greece , the gas flames at Mount Chimaera contributed to the legend of the fire-breathing creature Chimera . In ancient China , gas resulting from the drilling for brines was first used by about 400 BC. The Chinese transported gas seeping from

3150-435: The gas needs to be cooled down and compressed, as the friction in the pipeline causes the gas to heat up. Many existing pipelines in the US are close to reaching their capacity, prompting some politicians representing northern states to speak of potential shortages. The large trade cost implies that natural gas markets are globally much less integrated, causing significant price differences across countries. In Western Europe ,

3220-512: The gas pipeline network is already dense. New pipelines are planned or under construction between Western Europe and the Near East or Northern Africa . Whenever gas is bought or sold at custody transfer points, rules and agreements are made regarding the gas quality. These may include the maximum allowable concentration of CO 2 , H 2 S and H 2 O . Usually sales quality gas that has been treated to remove contamination

3290-896: The gas to consumer markets. Until the early part of the 20th century, most natural gas associated with oil was either simply released or burned off at oil fields. Gas venting and production flaring are still practised in modern times, but efforts are ongoing around the world to retire them, and to replace them with other commercially viable and useful alternatives. In addition to transporting gas via pipelines for use in power generation, other end uses for natural gas include export as liquefied natural gas (LNG) or conversion of natural gas into other liquid products via gas to liquids (GTL) technologies. GTL technologies can convert natural gas into liquids products such as gasoline, diesel or jet fuel. A variety of GTL technologies have been developed, including Fischer–Tropsch (F–T), methanol to gasoline (MTG) and syngas to gasoline plus (STG+). F–T produces

3360-518: The ground in crude pipelines of bamboo to where it was used to boil salt water to extract the salt in the Ziliujing District of Sichuan . Natural gas was not widely used before the development of long distance pipelines in the early twentieth century. Before that, most use was near to the source of the well, and the predominant gas for fuel and lighting during the industrial revolution was manufactured coal gas. The history of natural gas in

3430-442: The higher-molecular weight hydrocarbons to produce natural gas with energy content between 35–39 megajoules per cubic metre (950–1,050 British thermal units per cubic foot). The processed natural gas may then be used for residential, commercial and industrial uses. Natural gas flowing in the distribution lines is called mid-stream natural gas and is often used to power engines which rotate compressors. These compressors are required in

3500-698: The island has changed Melkøya completely. On 21 August 2007, the gas from the Snøhvit field began flowing to Melkøya. The endangered black-legged kittiwake adopted a man-made cliff at the facility for nesting, making it one of the largest kittiwake colonies in the world. Natural gas Natural gas (also called fossil gas, methane gas , or simply gas ) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane (95%) in addition to various smaller amounts of other higher alkanes . Traces of carbon dioxide , nitrogen , hydrogen sulfide , and helium are also usually present. Methane

3570-594: The largest proven gas reserves. Sources that consider that Russia has by far the largest proven reserves include the US Central Intelligence Agency (47,600 km ) and Energy Information Administration (47,800 km ), as well as the Organization of Petroleum Exporting Countries (48,700 km ). Contrarily, BP credits Russia with only 32,900 km , which would place it in second, slightly behind Iran (33,100 to 33,800 km , depending on

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3640-443: The methane as a fuel. Today, ethane is an important petrochemical feedstock and is separated from the other components of natural gas in most well-developed gas fields. Ethane can also be separated from petroleum gas , a mixture of gaseous hydrocarbons produced as a byproduct of petroleum refining . Ethane is most efficiently separated from methane by liquefying it at cryogenic temperatures. Various refrigeration strategies exist:

3710-445: The most economical process presently in wide use employs a turboexpander , and can recover more than 90% of the ethane in natural gas. In this process, chilled gas is expanded through a turbine , reducing the temperature to approximately −100 °C (−148 °F). At this low temperature, gaseous methane can be separated from the liquefied ethane and heavier hydrocarbons by distillation . Further distillation then separates ethane from

3780-433: The natural gas can be transported. Natural gas extracted from oil wells is called casinghead gas (whether or not truly produced up the annulus and through a casinghead outlet) or associated gas. The natural gas industry is extracting an increasing quantity of gas from challenging, unconventional resource types : sour gas , tight gas , shale gas , and coalbed methane . There is some disagreement on which country has

3850-441: The pores of the gas reservoir get depleted. One method to deal with this problem is to re-inject dried gas free of condensate to maintain the underground pressure and to allow re-evaporation and extraction of condensates. More frequently, the liquid condenses at the surface, and one of the tasks of the gas plant is to collect this condensate. The resulting liquid is called natural gas liquid (NGL) and has commercial value. Shale gas

3920-626: The presence of liquid ethane in Ontario Lacus. Several significantly larger hydrocarbon lakes, Ligeia Mare and Kraken Mare being the two largest, were discovered near Titan's north pole using radar data gathered by Cassini. These lakes are believed to be filled primarily by a mixture of liquid ethane and methane. In 1996, ethane was detected in Comet Hyakutake , and it has since been detected in some other comets . The existence of ethane in these distant solar system bodies may implicate ethane as

3990-432: The propagation of the ethyl radical: The combustion of ethane releases 1559.7 kJ/mol, or 51.9 kJ/g, of heat, and produces carbon dioxide and water according to the chemical equation : Combustion may also occur without an excess of oxygen, yielding carbon monoxide , acetaldehyde , methane , methanol , and ethanol . At higher temperatures, especially in the range 600–900 °C (1,112–1,652 °F), ethylene

4060-402: The reductions of propionitrile ( ethyl cyanide ) and ethyl iodide with potassium metal, and, as did Faraday, by the electrolysis of aqueous acetates. They mistook the product of these reactions for the methyl radical ( CH 3 ), of which ethane ( C 2 H 6 ) is a dimer . This error was corrected in 1864 by Carl Schorlemmer , who showed that the product of all these reactions

4130-682: The result is ethane: In Earth's atmosphere, hydroxyl radicals convert ethane to methanol vapor with a half-life of around three months. It is suspected that ethane produced in this fashion on Titan rains back onto the moon's surface, and over time has accumulated into hydrocarbon seas covering much of the moon's polar regions. In mid-2005, the Cassini orbiter discovered Ontario Lacus in Titan's south polar regions. Further analysis of infrared spectroscopic data presented in July 2008 provided additional evidence for

4200-543: The source). It is estimated that there are about 900,000 km of "unconventional" gas such as shale gas, of which 180,000 km may be recoverable. In turn, many studies from MIT , Black & Veatch and the US Department of Energy predict that natural gas will account for a larger portion of electricity generation and heat in the future. The world's largest gas field is the offshore South Pars / North Dome Gas-Condensate field , shared between Iran and Qatar. It

4270-403: The stabilizing effect of hyperconjugation on the staggered conformation contributing to the phenomenon. Theoretical methods that use an appropriate starting point (orthogonal orbitals) find that hyperconjugation is the most important factor in the origin of the ethane rotation barrier. As far back as 1890–1891, chemists suggested that ethane molecules preferred the staggered conformation with

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4340-640: The third peak in December 2019, extraction continued to fall from March onward due to decreased demand caused by the COVID-19 pandemic in the US . The 2021 global energy crisis was driven by a global surge in demand as the world quit the economic recession caused by COVID-19, particularly due to strong energy demand in Asia. Because of its low density, it is not easy to store natural gas or to transport it by vehicle. Natural gas pipelines are impractical across oceans, since

4410-412: The transmission line to pressurize and repressurize the mid-stream natural gas as the gas travels. Typically, natural gas powered engines require 35–39 MJ/m (950–1,050 BTU/cu ft) natural gas to operate at the rotational name plate specifications. Several methods are used to remove these higher molecular weighted gases for use by the natural gas engine. A few technologies are as follows: In

4480-508: The two ends of the molecule askew from each other. Ethane occurs as a trace gas in the Earth's atmosphere , currently having a concentration at sea level of 0.5 ppb . Global ethane quantities have varied over time, likely due to flaring at natural gas fields . Global ethane emission rates declined from 1984 to 2010, though increased shale gas production at the Bakken Formation in

4550-400: The uncertainties in the final digits). Rotating a molecular substructure about a twistable bond usually requires energy. The minimum energy to produce a 360° bond rotation is called the rotational barrier . Ethane gives a classic, simple example of such a rotational barrier, sometimes called the "ethane barrier". Among the earliest experimental evidence of this barrier (see diagram at left)

4620-498: The worldwide extraction, access to natural gas has become an important issue in international politics, and countries vie for control of pipelines. In the first decade of the 21st century, Gazprom , the state-owned energy company in Russia, engaged in disputes with Ukraine and Belarus over the price of natural gas, which have created concerns that gas deliveries to parts of Europe could be cut off for political reasons. The United States

4690-477: Was in fact ethane. Ethane was discovered dissolved in Pennsylvanian light crude oil by Edmund Ronalds in 1864. At standard temperature and pressure, ethane is a colorless, odorless gas. It has a boiling point of −88.5 °C (−127.3 °F) and melting point of −182.8 °C (−297.0 °F). Solid ethane exists in several modifications. On cooling under normal pressure, the first modification to appear

4760-488: Was invented in Saudi Arabia in the late 1970s, ending any necessity for flaring. Satellite and nearby infra-red camera observations, however, shows that flaring and venting are still happening in some countries. Natural gas is used to generate electricity and heat for desalination . Similarly, some landfills that also discharge methane gases have been set up to capture the methane and generate electricity. Natural gas

4830-414: Was obtained by modelling the entropy of ethane. The three hydrogens at each end are free to pinwheel about the central carbon–carbon bond when provided with sufficient energy to overcome the barrier. The physical origin of the barrier is still not completely settled, although the overlap (exchange) repulsion between the hydrogen atoms on opposing ends of the molecule is perhaps the strongest candidate, with

4900-567: Was recovered in the course of recovering petroleum could not be profitably sold, and was simply burned at the oil field in a process known as flaring . Flaring is now illegal in many countries. Additionally, higher demand in the last 20–30 years has made production of gas associated with oil economically viable. As a further option, the gas is now sometimes re- injected into the formation for enhanced oil recovery by pressure maintenance as well as miscible or immiscible flooding. Conservation, re-injection, or flaring of natural gas associated with oil

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