Crude oil (from tour neft, from Persian oil..) - A natural oily flammable liquid with a specific smell, consisting mainly of a complex mixture of hydrocarbons of various molecular weights and some other chemical compounds. It refers to caustobiolites (fossil fuels).
The vast majority of oil fields is confined to the sedimentary rocks. The color of the oil is typically pure black. Sometimes it varies brown browns (from the dirty-yellow to dark brown, almost black), rarely found oil, painted in bright yellow-green color, and even colorless and rich-green oil. It has a specific smell, and range from mild to severe pleasant and very unpleasant. The color and odor of the oil to a large extent due to the presence of nitrogen-, sulfur- and oxygen-containing components, which are concentrated in the lubricating oil and the oil residue. Most petroleum hydrocarbons (excluding aromatics) pure devoid of smell and color.
Throughout the XX century in the XXI century, oil is one of the most important to mankind minerals.
The chemical composition and origin of oil is close to natural gas fuel and ozokerite. These resources are collectively called petrolytes. Petrolytes referred to even more extensive group of so-called caustobiolites - combustible minerals of biogenic origin, which include other fossil fuels (peat, brown coal and anthracite, shale).
Oil is found together with the gaseous hydrocarbons at depths of tens of meters to 5-6 km. However, at depths greater than 4.5-5 km dominated by gas and gas condensate deposits with a minor amount of light fractions. The maximum number of oil reservoirs located at a depth of 1-3 km. At shallow depths and natural exposures on the earth's surface oil is converted into a thick Malta, semi-solid asphalt and other entities - such as tar sands and bitumen.
Oil formation - phasic, the long process of formation of oil from the organic matter of sedimentary rocks (remains of ancient living organisms), according to the dominant nutrient (organic) theory of the origin of oil. This process takes tens or hundreds of millions of years. In XX century, a certain popularity, especially in the USSR, was the hypothesis of abiotic origin of oil from inorganic matter at great depths under enormous pressure and high temperatures, but the vast majority of evidence favors the biogenic theory. Abiogenically hypotheses are not allowed to make effective predictions for new discoveries.
Physical Properties [edit | edit wiki text]
Oil - the liquid from light brown (almost colorless) to dark brown (almost black) color (although there are examples of even emerald-green oil). The average molecular weight of 220-400 g / mol (rarely 450-470). Density 0,65-1,05 (usually 0,82-0,95) g / cm³; oil whose density is lower than 0.83, called light, 0,831-0,860 - average above 0.860 - heavy.
The density of oil, as well as other hydrocarbons, is highly dependent on temperature and pressure.
. It contains a large number of different organic substances, and therefore characterized not boiling, and the bubble point temperature of liquids (typically> 28 ° C, less ≥100 ° C in the case of heavy oil) and fractional composition - yield individual fractions was distilled first at atmospheric pressure and then under vacuum in a certain temperature range, usually up to 450-500 ° C (boiling over ~ 80% of the sample volume), at least 560-580 ° C (90-95%). The crystallization temperature of -60 to + 30 ° C; It depends mainly on the content of the paraffin oil (what it is, the higher the crystallization temperature) and light fractions (more than them, so that the temperature is lower). The viscosity varies widely (from 1.98 to 265.90 mm² / s for various oil produced in Russia), it is determined by the fractional composition of oil and its temperature (the higher it is and the greater the amount of light fractions, the lower the viscosity), and resin-asphaltene content materials (the more, the higher the viscosity). The specific heat of 1.7-2.1 kJ / (kg ∙ K); specific heat of combustion (lower) 43,7-46,2 MJ / kg; the dielectric constant of 2.0-2.5; electrical conductivity [specific] 2 ∙ 10-10 to 0.3 ∙ 10-18 Ohm-1 ∙ cm-1.
Oil - flammable liquid; a flash point of -35 to +121 ° C (dependent on the fractional composition and its content of dissolved gases). Oil soluble in organic solvents, not normally soluble in water, but it may form stable emulsions. The technology for separating oil from water and salts dissolved in it is carried out dehydration and desalting.
Physical Properties [edit | edit wiki text]
Oil - the liquid from light brown (almost colorless) to dark brown (almost black) color (although there are examples of even emerald-green oil). The average molecular weight of 220-400 g / mol (rarely 450-470). Density 0,65-1,05 (usually 0,82-0,95) g / cm³; oil whose density is lower than 0.83, called light, 0,831-0,860 - average above 0.860 - heavy.
The density of oil, as well as other hydrocarbons, is highly dependent on temperature and pressure.
. It contains a large number of different organic substances, and therefore characterized not boiling, and the bubble point temperature of liquids (typically> 28 ° C, less ≥100 ° C in the case of heavy oil) and fractional composition - yield individual fractions was distilled first at atmospheric pressure and then under vacuum in a certain temperature range, usually up to 450-500 ° C (boiling over ~ 80% of the sample volume), at least 560-580 ° C (90-95%). The crystallization temperature of -60 to + 30 ° C; It depends mainly on the content of the paraffin oil (what it is, the higher the crystallization temperature) and light fractions (more than them, so that the temperature is lower). The viscosity varies widely (from 1.98 to 265.90 mm² / s for various oil produced in Russia), it is determined by the fractional composition of oil and its temperature (the higher it is and the greater the amount of light fractions, the lower the viscosity), and resin-asphaltene content materials (the more, the higher the viscosity). The specific heat of 1.7-2.1 kJ / (kg ∙ K); specific heat of combustion (lower) 43,7-46,2 MJ / kg; the dielectric constant of 2.0-2.5; electrical conductivity [specific] 2 ∙ 10-10 to 0.3 ∙ 10-18 Ohm-1 ∙ cm-1.
Oil - flammable liquid; a flash point of -35 to +121 ° C (dependent on the fractional composition and its content of dissolved gases). Oil soluble in organic solvents, not normally soluble in water, but it may form stable emulsions. The technology for separating oil from water and salts dissolved in it is carried out dehydration and desalting.
Chemical composition [edit | edit wiki text]
The oil is a mixture of about a thousand individual compounds, most of which - the liquid hydrocarbons (> 500 or substances generally 80-90% by weight) and heteroatomic organic compounds (4.5%), mainly sulfur (about 250 compounds), nitrogen ( > 30 species) and oxygen (about 85 compounds), and organometallic compounds (mostly nickel and vanadium); other components - dissolved hydrocarbon gases (C1-C4, from a few tenths up to 4%), water (from traces to 10%), mineral salts (mainly chloride, 0,1-4000 mg / l or more) solutions of organic salts acids, et al., mechanical impurities.
Mainly in paraffin oil are presented (usually 30-35% less 40-50 by volume) and naphthenic (25-75%) of the compound. To a lesser extent - aromatic compounds (10-20, at least 35%) and a mixed, or hybrid, the structure (e.g., paraffin-naphthenic, aromatic-naphthene).
Apart from hydrocarbons in the oil composition comprises compounds containing impurity atoms. Sulphur - H2S, mercaptans, mono- and disulfides, thiophenes and thiophane and polycyclic etc. (70-90% is concentrated in the residual products - fuel oil and tar)..; nitrogen - preferably pyridine homologs, quinoline, indole, carbazole, pyrrole, and porphyrins (mainly concentrated in the heavy fractions and residual); oxygen - naphthenic acids, phenols, resinous-asphaltene and other substances (typically concentrated in higher boiling fractions).. The elemental composition (%): 82-87 ° C; 11-14,5 N; 0,01-6 S (rarely to 8); 0,001-1,8 N; 0,005-0,35 O (rarely to 1.2). A total oil found in more than 50 elements. Thus, along with the above, the oil present in V (10-5 - 10-2%), Ni (10-4-10-3%), Cl (up to 2 x 10-2% of traces), etc.. The contents of these compounds and impurities in the raw materials of different fields varies widely, so to speak of the average chemical composition of the oil is possible only conditionally.
Often the oil reservoir occupies only part of the collector, and therefore, depending on the nature and degree of porosity rock cementation (heterogeneous deposits), is found varying degrees of saturation with oil in its separate sections within the deposit itself. Sometimes the reason for this is due to the presence of deposits of non-productive areas. Typically the oil in the reservoir is accompanied by water, which restricts the reservoir layers fall down or across its sole. In addition, each oil reservoir together with it is so on. N. Foil or residual water, enveloping rock particles (sand) and the pore walls. In the case of wedging rock collector or cut his faults, shifts, and so on. N. Disjunctive violations deposit may either completely or partially limited low permeable rocks. In the upper parts of the oil deposits sometimes concentrated gas (ie. N. "Gas cap"). Debit wells, in addition to the physical properties of the reservoir, its capacity and saturation, determined by the pressure of dissolved gas in the oil and territorial waters. When oil wells is not possible to entirely remove all the oil from the reservoir, a significant amount of it remains in the bowels of the earth's crust (see. Nefteotdacha and oil production). For a more complete oil extraction special techniques are used, of which great importance is the flooding method (of perimeter, vnutrikonturnogo, focal). Oil reservoir is under pressure (elastic expansion and / or the edge of the water and / or gas is dissolved and the gas cap), so that the opening of deposits, especially the first well, accompanied by the risk gazonefteproyavleny (very rare oil gusher emissions).
application
Gas station
Directly crude oil is almost never used (along with the crude oil used to Nerozin peskozaschity - fixing sand dunes by the wind blowing in the construction of transmission lines and pipelines). To get out of it technically valuable products, mainly motor fuels, solvents and raw materials for the chemical industry, it is processed. Oil holds a leading position in the global energy balance: its share in the total consumption of energy was 33.6% in 2010. In the future, this share will decrease [citation needed 1457 days] due to the increase in the use of nuclear and other types of energy as well as increasing and reducing the production cost.
Loading oil tanker
The pipeline in Portugal
With the rapid development of the world's petroleum and petrochemical industries, the demand for oil is increased, not only to enhance the production of fuels and oils but also as a valuable source of raw materials for the production of synthetic rubber, fibers, plastics, surfactants, detergents, plasticizers, additives, dyes, et al. (more than 8% of the world production volume). Among the oil obtained from the starting materials most widely used for these plants found: paraffin hydrocarbons - methane, ethane, propane, butanes, pentanes, hexanes, as well as high molecular weight (10-20 carbon atoms in the molecule); naphthenic; Aromatic hydrocarbons - benzene, toluene, xylenes, ethylbenzene; olefin and diolefin - ethylene, propylene, butadiene; acetylene. Oil is unique combination of qualities: high energy density (thirty percent higher than that of the highest quality coal), oil is easy to transport (compared to gas or coal, for example), and finally, of the oil is easy to get a lot of the above mentioned products. The depletion of oil resources, rising prices for it, and others. Causes caused an intensive search for substitutes for liquid fuels.
Oil prices, as well as any other items are determined by supply and demand. If the proposal falls, prices rise as long as the demand is equal to the proposal.
Especially oil, however, is that in the short term demand maloelastichen: the rise in prices has little effect on demand. Therefore, even a slight drop in oil supply leads to a sharp rise in prices.
In the medium term (5-10 years) and long term (decades) term demand, however, is continuously increasing due to the increase in the number of vehicles and similar equipment. By repeated observation, the oil price rise in world inflation accelerates dollar, and it is believed that this is due to the fact that the United States - the largest consumer of oil in the world. However, accurate support of this view is not known. In addition, recently the world's largest oil consumers were China and India.
In XX century, oil demand growth is balanced by the exploration of new deposits, and allow to increase oil production. However, many believe that in the XXI century, oil fields are exhausted, and the imbalance between the demand for oil and its proposal will lead to a sharp rise in prices - the oil crisis occurs.
In addition, from the level of oil prices and oil prices essentially depend on natural gas.