Extraction from underground reservoirs
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Liquid and ga搜索引擎优化ushydrocarbonsare so intimately associated in nature that it has become customary to shorten the expression petroleum and natural gas to petroleum when referring to both. The wordpetroleum(literally rock oil from the Latinpetra, rock or stone, andoleum, oil) was first used in 1556 in atreatisepublished by the German mineralogist Georg Bauer, known asGeorgius Agricola.
, complex mixture ofhydrocarbonsthat occur inEarthinliquid, ga搜索引擎优化us, or solid form. The term is often restricted to the liquid form, commonly calledcrude oil, but, as a technical term, petroleum also includesnatural gasand the viscous or solid form known asbitumen, which is found intar sands. The liquid and ga搜索引擎优化us phases of petroleumconstitutethe most important of the primaryfossil fuels.
Several centuries later, Spanish explorers discovered oil seeps in present-day Cuba,Mexico, Bolivia, and Peru. Oil seeps were plentiful inNorth Americaand were also noted by early explorers in what are now New York and Pennsylvania, where American Indians were reported to have used the oil for medicinal purposes.
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The significance of oil as a world energy source is difficult to overdramatize. The growth in energy production during the 20th century was unprecedented, and increasing oil production has been by far the major contributor to that growth. By the 21st century an immense and intricate value chain was moving approximately 100 million barrels of oil perdayfrom producers to consumers. The production andconsumptionof oil is of vital importance tointernational relationsand has frequently been a decisive factor in the determination offoreign policy. The position of a country in this system depends on its production capacity as related to its consumption. The possession of oil deposits is sometimes the determining factor between a rich and a poor country. For any country, the presence or absence of oil has major economic consequences.
Thearomatic seriesis an unsaturated closed-ring series. Its most common member,benzene(C6H6), is present in all crude oils, but the aromatics as a series generally constitute only a small percentage of most crudes.
is Iraqs most valuable mineralthe country has some of the worlds largest known reserves and, before the Iran-Iraq War, was the second largest oil-exporting state. Oil production contributes the largest single portion to GDP and constitutes almost all of Iraqs
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Small surface occurrences of petroleum in the form of natural gas and oil seeps have been known from early times. The ancient Sumerians, Assyrians, and Babylonians used crude oil, bitumen, andasphalt(pitch) collected from large seeps at Tuttul (modern-day Ht) on the Euphrates for many purposes more than 5,000 years ago. Liquid oil was first used as amedicineby the ancient Egyptians, presumably as a wound dressing, liniment, and laxative. TheAssyriansused bitumen as a means of punishment by pouring it over the heads of lawbreakers.
Brazil produces the majority of its petroleum and some natural gas, mainly from offshore fields along the continental shelf. Drilling was confined to the Northeast, in the Bahia basin just north of Salvador, from 1940 to the 1960s, after which the
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Petroleum is Iraqs most valuable mineralthe country has some of the worlds largest known reserves and, before the Iran-Iraq War, was the second largest oil-exporting state. Oil production contributes the largest single portion to GDP and constitutes almost all of Iraqs
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Oil products were valued asweaponsof war in the ancient world. The Persians usedincendiaryarrows wrapped in oil-soaked fibres at the siege of Athens in 480bce. Early in the Common Era the Arabs and Persians distilled crude oil to obtain flammable products for military purposes. Probably as a result of the Arab invasion of Spain, the industrial art ofdistillationinto illuminants became available in western Europe by the 12th century.
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Crude oil is anorganic compounddivided primarily intoalkeneswith single-bond hydrocarbons of the form CnH2n+2or aromatics having six-ring carbon-hydrogen bonds, C6H6. Most crude oils are grouped into mixtures of various and seemingly endless proportions. No two crude oils from different sources are completely identical.
On a timescale within the span of prospective human history, the utilization of oil as a major source of energy will be a transitory affair lasting only a few centuries. Nonetheless, it will have been an affair of profound importance to world industrialization.
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Thenaphthenic serieshas the general formula CnH2nand is a saturated closed-ring series. This series is an important part of all liquid refinery products, but it also forms most of the complex residues from the higher boiling-point ranges. For this reason, the series is generally heavier. The residue of the refining process is anasphalt, and the crude oils in which this series predominates are called asphalt-base crudes.
The stage was set for the firstwellspecifically drilled for oil, a project undertaken by AmericanentrepreneurEdwin L. Drakein northwestern Pennsylvania. The completion of the well inAugust1859 established the groundwork for the petroleum industry and ushered in the closely associated modern industrial age. Within a short time, inexpensive oil from underground reservoirs was being processed at already existing coal oil refineries, and by the end of the century oil fields had been discovered in 14 states from New York to California and from Wyoming to Texas. During the same period, oil fields were found in Europe and EastAsiaas well.
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Although oil consists basically ofcompoundsof only two elements,carbonandhydrogen, these elements form a large variety of complex molecular structures. Regardless of physical or chemical variations, however, almost allcrude oilranges from 82 to 87 percent carbon by weight and 12 to 15 percent hydrogen. The more-viscousbitumensgenerally vary from 80 to 85 percent carbon and from 8 to 11 percent hydrogen.
TheIndustrial Revolutionbrought an ever-growing demand for a cheaper and more convenient source of lubricants as well as ofilluminatingoil. It also required better sources ofenergy. Energy had previously been provided by human and animal muscle and later by the combustion of such solid fuels aswoodpeat, and coal. These were collected with considerable effort and laboriously transported to the site where the energy source was needed. Liquid petroleum, on the other hand, was a more easily transportable source of energy. Oil was a much more concentrated and flexible form of fuel than anything previously available.
At the beginning of the 20th century, the Industrial Revolution had progressed to the extent that the use of refined oil for illuminants ceased to be of primary importance. The oil and gas industry became the major supplier of energy largely because of the advent of theinternal-combustion engine, especially those in automobiles. Although oilconstitutesa majorpetrochemicalfeedstock, its primary importance is as an energy source on which the world economy depends.
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At least two-thirds of the worlds known crude oil and natural gas reserves are found in Asia; the proportion may prove higher as Siberia, the Caspian basin, and the seas of southeastern Asia are further explored. Many of the island chains
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The economic potential for the internal-combustion engine lay in the need for a light locomotive engine. This could not be provided by the gas engine, depending on a piped supply of town gas, any more than by the steam engine, with its need for
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The burning of all fossil fuels (coal andbiomassincluded) releases large quantities ofcarbon dioxide(CO2) into theatmosphere. The CO2molecules do not allow much of the long-wavesolar radiationabsorbed by Earths surface to reradiate from the surface and escape into space. The CO2absorbs upward-propagatinginfrared radiationand reemits a portion of it downward, causing the lower atmosphere to remain warmer than it would otherwise be. This phenomenon has the effect ofenhancingEarths naturalgreenhouse effect, producing what scientists refer to asanthropogenic(human-generated)global warming. There is substantial evidence that higher concentrations of CO2and othergreenhouse gaseshave contributed greatly to the increase of Earths near-surface mean temperature since 1950.
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Known petroleum and natural gas reserves are inadequate for Europes rising requirements. European Russia contains the large Volga-Ural field, while Romania has reserves in the Carpathian and Subcarpathian zones. Norway and the United Kingdom have tapped gas and oil from
Inlubrication: Liquid, oily lubricants.
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Thealkaneparaffinic seriesof hydrocarbons, also called themethane(CH4) series,comprisesthe most common hydrocarbons in crude oil. The majorconstituentsofgasolineare theparaffinsthat are liquid at normal temperatures but boil between 40 C and 200 C (100 F and 400 F). The residues obtained by refining lower-density paraffins are bothplasticand solidparaffin waxes.
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Until the beginning of the 19th century,illuminationin theUnited Statesand in many other countries was little improved over that which was known during the times of the Mesopotamians, Greeks, and Romans. Greek and Roman lamps and light sources often relied on the oils produced by animals (such as fish and birds) and plants (such as olive, sesame, and nuts). Timber was also ignited to produce illumination. Since timber was scarce in Mesopotamia, rock asphalt (sandstone or limestone infused with bitumen or petroleum residue) was mined and combined with sand and fibres for use in supplementing building materials. The need for better illumination that accompanied the increasing development of urban centres made it necessary to search for new sources of oil, especially since whales, which had long provided fuel for lamps, were becoming harder and harder to find. By the mid-19th centurykerosene, or coal oil, derived fromcoalwas in common use in both North America and Europe.