In oil exploitation, it refers to the oil stored underground;
In pipeline transportation, it refers to crude oil that has not been cracked and separated;
In oil refining, it refers to oil as raw material. ...
2. In general, crude oil can't be directly used in daily life, and it must go through a series of treatments, but it's not called "decomposition".
3. The following is the academic definition of crude oil:
concept
Petroleum, also known as crude oil or black gold, is a viscous dark brown (sometimes a little green) liquid. There are oil reserves in some parts of the upper crust. It is composed of different hydrocarbons, and the main component is alkanes. In addition, petroleum also contains sulfur, oxygen, nitrogen, phosphorus, vanadium and other elements. However, the oil composition and appearance of different oil fields may be very different. Petroleum is mainly used as fuel oil and gasoline, which constitute one of the most important primary energy sources in the world at present. Petroleum is also the raw material of many chemical industrial products, such as solvents, fertilizers, pesticides and plastics. At present, 88% of the oil mined is used as fuel, and another 12% is used as chemical raw materials.
In crude oil, carbon accounts for 83%-87%, hydrogen accounts for11%-kloc-0/4%, and other impurities are sulfur, nitrogen, oxygen and metals.
The discovery of oil
China is the first country to discover and apply oil in the world.
900 years ago, Shen Kuo, a famous scholar in the Song Dynasty, put forward outstanding views on the knowledge of paleogeology and paleontology in China. His view is 400 years earlier than that of western European scholars who first realized that fossils are biological remains. When Shen Kuo was once ordered to inspect Hebei West Road, he found that there were many snail shells and egg-shaped stones between the cliffs of Taihang Mountain, thus inferring that it was originally an Archean seashore, which was made up of seashore shells and sediment, and correctly inferring the changes of land and sea according to the remains of paleontology.
1080 (three years of Yuanfeng), from Shen Kuo to Yanzhou (now Yan 'an). During his tenure, he discovered and inspected Lu Yan's oil reserves and uses. He said, "Lu Yan has oil. As the old saying goes, Gaonu County produces fertile water, which is also the case. Born in water, sand and stones are mixed with spring water, forcing people out. The natives collected it in a jar with a pheasant tail bag. It looks like pure paint and burns like hemp, but the smoke is very thick and the curtains are all black. If it is suspected that the smoke is available, try to sweep the coal into ink. Black as paint, ink does not come loose. It is a great achievement, and it is also known as' Yanzhou Stone Liquid'. This thing will be popular all over the world after it is given. At most, it is covered with oil, born in endless land, and sometimes it is exhausted. " Judging from the above records, Shen Kuo not only discovered oil, but also knew its use. Although his so-called use at that time focused on the manufacture of tobacco and ink, he did predict that "this thing will be popular in the world", and this idea has been verified today. Today, the word "oil" is also used by him, and he wrote China's earliest oil poem: "Erlang Mountain is snowy, the school is full of people, the clothes are not old, and the oil is like Fuyang dust."
1867 human beings officially entered the oil age. In this year, the proportion of oil in the primary energy consumption structure reached 40.4%, while the proportion of coal decreased to 38.8%. The increase of oil demand and the expansion of oil trade are due to the large-scale use of oil in industrial production. Before the first world war, oil was mainly used for lighting, and the United States and Russia, which were big oil producers, were also big consumers. In the First World War, the strategic value of oil has initially appeared. Because of its high combustion efficiency and portability, it has great strategic significance for improving the combat effectiveness of the army. In the 1920s, as oil became the power of internal combustion engines, the demand and trade of oil expanded rapidly. According to the statistics of Wang Yadong, by 1929, the oil trade volume had reached165438+700 million US dollars. During this period, the international oil cargo flows mainly from the United States and Venezuela to Western Europe. At the same time, the oil in the Soviet Union was rapidly restored and developed. By the end of 1930s, the United States and the Soviet Union became major oil exporters, and international oil trade began to occupy a prominent position in the global energy trade, which promoted the rapid growth of international energy trade and shook the dominant position of coal in the international energy market. During the Second World War, oil played an important role. During World War II, the United States became a major energy supplier to its allies. After World War II, the United States once controlled two-thirds of the world's crude oil production. From 1859, when the first oil well was drilled in Pennsylvania, to the period after World War II, the world energy map was called the "Gulf of Mexico era". Wang Yadong believes that the formation and development of the "Gulf Era" is also a period when the political, economic and military strength of the United States continues to expand and finally establishes its hegemony in the western world. This period was almost synchronized with the development of domestic oil in the United States. The control of oil by the United States in the "Gulf of Mexico era" promoted and consolidated the position of the United States in the world political and economic structure. Oil has become an important booster for the United States to establish world hegemony.
Classification and physicochemical properties
Classification by composition: paraffin-based crude oil, naphthenic base crude oil and intermediate base crude oil;
Classification by sulfur content: ultra-low sulfur crude oil, low sulfur crude oil, sulfur crude oil and high sulfur crude oil;
Classification by specific gravity: light crude oil, medium crude oil and heavy crude oil are divided into three categories.
The properties of crude oil include physical properties and chemical properties. Physical properties include color, density, viscosity, freezing point, solubility, calorific value, fluorescence, optical rotation and so on. Chemical properties include chemical composition, composition and impurity content.
Density: Generally, the relative density of crude oil is between 0.75-0.95, and a few are greater than 0.95 or less than 0.75. The relative density between 0.9- 1.0 is called heavy crude oil, and less than 0.9 is called light crude oil.
Viscosity: The viscosity of crude oil refers to the internal friction resistance generated when crude oil flows. The viscosity of crude oil depends on temperature, pressure, dissolved gas and its chemical composition. Its viscosity decreases with the increase of temperature, increases with the increase of pressure, decreases with the increase of dissolved gas, and decreases with the increase of light oil components. The viscosity of crude oil varies greatly, generally at 1 ~ 100 MPa? In the United States, high-viscosity crude oil is commonly known as heavy oil, which has poor fluidity and is difficult to develop. Generally speaking, crude oil with high viscosity has higher density.
Freezing point: The temperature at which crude oil cools from liquid to solid is called freezing point. The freezing point of crude oil is about -50℃ ~ 35℃. The freezing point is related to the content of components in petroleum. High content of light components, low freezing point, high content of heavy components, especially high content of paraffin, so the freezing point is high.
Wax content: Wax content refers to the percentage of paraffin and ceresin contained in crude oil at normal temperature and pressure. Paraffin wax is a white or yellowish solid, composed of higher alkanes, and its melting point is 37℃ ~ 76℃. Paraffin is dissolved in oil in the form of colloid underground, and can be separated from oil when the pressure and temperature decrease. The temperature at which paraffin in formation crude oil begins to crystallize and precipitate is called wax precipitation temperature. The higher the wax content, the higher the wax precipitation temperature.
Wax deposition temperature is high, and oil wells are prone to wax deposition, which is not conducive to oil well management. Sulfur content refers to the percentage of sulfur (sulfide or elemental sulfur) in crude oil. The sulfur content in crude oil is small, generally less than 1%, but it has a great influence on the properties of crude oil, which is corrosive to pipelines and harmful to human health. According to the different sulfur content, it can be divided into low sulfur or sulfur-containing petroleum.
Gum content: Gum content refers to the percentage of gum contained in crude oil. The gum content of crude oil is generally between 5% and 20%. Gum refers to polycyclic aromatic hydrocarbon compounds with relatively large molecular weight (300 ~ 1000) in crude oil, which are dissolved in crude oil in the form of semi-solid dispersion. Colloids are easily soluble in organic solvents such as petroleum ether, lubricating oil, gasoline and chloroform.
Others: The asphaltene content in crude oil is less, generally less than 1%. Asphaltene is a black solid substance with high molecular weight (greater than 1000) and polycyclic structure. Insoluble in ethanol and petroleum ether, soluble in benzene, chloroform and carbon disulfide. When the asphaltene content increases, the quality of crude oil deteriorates.
Hydrocarbons in crude oil are mainly divided into alkanes, cycloalkanes and aromatics. According to the different composition of hydrocarbons, it can be divided into three types: paraffin-based oil, naphthenic base oil and intermediate base oil. Paraffin-based petroleum contains more alkanes; Cycloalkyl petroleum contains more naphthenes and aromatics; Intermediate base oil is between the two.
At present, the crude oil that has been exploited in China is mainly low sulfur paraffin. Crude oil in Daqing and other places belongs to this category. Among them, the most representative Daqing crude oil has low sulfur content, high wax content and high freezing point, which can produce high-quality kerosene, diesel oil, solvent oil, lubricating oil and industrial paraffin. Shengli crude oil has high gum content (29%), high specific gravity (about 0.9 1) and high wax content (about 15-2 1%), which belongs to the sulfur-bearing intermediate group. Gasoline fraction has good lead sensitivity and is rich in naphthenes and aromatics, so it is a good reforming raw material.
Unit of measurement for oil.
The most commonly used unit of measurement for oil is the capacity unit, which is 42 gallons. Because the density of oil produced in different places is different, the weight of a barrel of oil is different. Generally speaking, a ton of oil has about 8 barrels. See the table below for the specific conversion relationship.
Liter (l) cubic meter (m3) gallon (US) gallon (UK) barrel (oil)
158.98 0. 15898 42 34.973 1
1 0.00 1 0.264 18 0.2 1998 0.00629
1000 1 264. 18 2 19.98 6.30
Storage and handling
1. Basic requirements for storage of crude oil and petroleum products
The main storage methods of crude oil and oil products are bulk storage and bulk storage. Bulk storage refers to storage in the form of standard barrels, and bulk storage refers to storage in the form of oil tanks. Oil tanks can be divided into metal tanks and non-metal tanks, and metal tanks can be divided into vertical cylinders and horizontal cylinders. According to the different construction methods of oil depots, bulk crude oil or oil products can also be divided into aboveground, semi-underground and underground, water-sealed cavern and underwater storage. However, no matter which storage method is adopted, the storage of crude oil, especially oil products, should meet the following basic requirements:
(1) Anti-deterioration
In the process of oil storage, in order to ensure the quality of oil products, attention must be paid to reducing the influence of temperature, air and moisture, sunlight and metals on oil products.
(2) Reduce losses
At present, the usual practices of oil depots are: selecting floating roof oil tanks and internal floating roof oil tanks; The baffle of the breathing valve is selected below the breathing valve of the oil tank; Spray water to cool down.
(3) Improve the safety of oil storage.
Because oil products have high fire and explosion risks, it is necessary to reduce the explosion sensitivity of oil products and apply materials with good flame retardant properties.
2, the basic requirements of crude oil and oil loading and unloading
The loading and unloading of crude oil and oil products are nothing more than the following forms: railway loading and unloading, waterway loading and unloading, highway loading and unloading and direct pipeline transportation. According to the different oil properties, it can be divided into light oil loading and unloading and sticky oil loading and unloading; Considering the oil loading and unloading technology, it can be divided into three types: loading and unloading, gravity flow and pumping. However, in addition to direct pipeline transportation, no matter what loading and unloading methods are adopted, the loading and unloading of crude oil and oil products must meet the following basic requirements:
(1) must be completed by special facilities and equipment.
Special facilities for loading and unloading crude oil and oil products mainly include: special railway lines and oil tankers, oil terminals or berthing points, oil tankers, trestle bridges or operating platforms, etc. Special equipment mainly includes: loading and unloading crane pipe, oil collecting pipe, oil pipeline and oil pump, oil filling equipment, heavy oil heating equipment, flowmeter, etc.
(2) It must be completed in the special operation area.
There is a special working area for loading and unloading crude oil and petroleum products. These special working areas are usually isolated from the surrounding environment and must meet the strict requirements of fire prevention, explosion prevention, lightning protection and static electricity prevention.
(3) It must be completed by specially trained professional and technical personnel.
(4) There are strict requirements on loading and unloading time and speed.
Brief introduction of oil futures knowledge
The oil crisis in the early 1970s brought a huge impact on the world oil market, and the sharp fluctuation of oil prices directly led to the emergence of oil futures. After the birth of oil futures, its trading volume has been growing rapidly, and now it has surpassed metal futures, which is an important part of the international futures market.
Crude oil futures are the most important oil futures. At present, there are four important crude oil futures contracts in the world: NYMEX light sweet crude oil West Texas Intermediate, London International Petroleum Exchange (IPE) Brent and Singapore International Financial Exchange (SIMEX) Dubai sour crude oil. Other oil futures include heating oil, fuel oil, gasoline and light diesel oil. NYMEX West Texas Intermediate crude oil futures contract specifications are 65,438+0,000 barrels per lot, and the quotation unit is USD/barrel. After its launch, this contract is the most successful commodity futures contract in history, and its transaction price has become the focus of international oil market.
As of June 2002, 65438+ 10 1, the estimated proven oil reserves in the world are1413.09 million tons, and Saudi Arabia ranks first in the world. In 20001year, the global crude oil output was 365,438+800 million tons, and the top five were Russia, Saudi Arabia, the United States, China and Norway. Among them, the output of Russian and China increased by 9% and 1.8% respectively. Russia replaced Saudi Arabia as the world's largest oil producer from the second place last year, while China rose to the fourth place from the fifth place last year.
Oil is the "blood of industrial production" and an important strategic material. In order to safeguard their own interests, the world oil-producing countries established the Organization of Petroleum Exporting Countries (OPEC) in September of 1960. 13 member countries: Iraq, Iran, Kuwait, Saudi Arabia, Venezuela, Algeria, Ecuador, Canada, Indonesia, Libya and Nigeria. Headquartered in Vienna, Austria. The oil reserves of the Organization of Petroleum Exporting Countries recently reached 1. 1.33 billion tons, accounting for nearly 80% of the world's total reserves.
China's oil demand is growing rapidly. Since 1993, it has become a net importer of oil. At present, it imports more than 70 million tons of crude oil every year and spends nearly 20 billion US dollars. The year before last, due to the rising international oil price, it paid billions of dollars more. At present, China's oil supply, demand and price are increasingly dependent on foreign resources, and the risks it bears are also increasing. Domestic enterprises have a high voice for resuming oil futures trading. In fact, China has made a successful exploration in the field of oil futures. At the beginning of 1993, the former Shanghai Petroleum Exchange successfully launched oil futures trading. Later, the former South China Commodity Futures Exchange, the former Beijing Petroleum Exchange and the former Beijing Commodity Exchange successively launched oil futures contracts. Among them, the former Shanghai Petroleum Exchange has the largest trading volume and relatively standardized operation, accounting for about 70% of the national oil futures market share. Its standard futures contracts mainly include Daqing crude oil, 90 # gasoline, 0 # diesel oil and 250 # fuel oil. By the beginning of 1994, the daily average trading volume of the former Shanghai Petroleum Exchange had surpassed that of the Singapore International Financial Exchange (SIMEX), the third largest energy futures market in the world, which had a great impact at home and abroad. China's successful practice in the field of oil futures in the past provides valuable experience for future oil futures trading.