Modern technologies for deepening oil refining. The current state of oil refining in Russia Modern technologies for oil refining

Delivery and reception of oil
In Russia, the main volumes of crude oil supplied for processing are delivered to refineries from producing associations via main oil pipelines. Small quantities of oil, as well as gas condensate, are shipped by rail. In oil-importing countries with access to the sea, delivery to port refineries is carried out by water transport.
Raw materials accepted at the plant enter the appropriate containers commodity base(Fig. 1), connected by pipelines with all technological units of the refinery. The amount of oil received is determined according to instrumental accounting, or by measurements in raw containers.

Preparation of oil for processing (electric desalination)
Crude oil contains salts that cause severe corrosion of process equipment. To remove them, the oil coming from the feed tanks is mixed with water, in which the salts dissolve, and enters the ELOU - electrical desalination plant(Fig. 2). The desalination process is carried out in electric dehydrators- cylindrical devices with electrodes mounted inside. Under the influence of a high voltage current (25 kV or more), the mixture of water and oil (emulsion) is destroyed, water is collected at the bottom of the apparatus and pumped out. For more effective destruction of the emulsion, special substances are introduced into the raw material - demulsifiers. Process temperature - 100-120°C.

Primary oil refining
Desalted oil from ELOU is supplied to the atmospheric vacuum distillation unit, which at Russian refineries is abbreviated ABT - atmospheric vacuum tube. This name is due to the fact that the heating of raw materials before separating it into fractions is carried out in coils tube furnaces(Fig. 6) due to the heat of fuel combustion and the heat of flue gases.
AWT is divided into two blocks - atmospheric and vacuum distillation.

1. Atmospheric distillation
Atmospheric distillation (Fig. 3.4) is intended for selection light oil fractions- gasoline, kerosene and diesel, boiling up to 360°C, the potential yield of which is 45-60% for oil. The rest of the atmospheric distillation is fuel oil.
The process consists in separating the oil heated in the furnace into separate fractions in distillation column- a cylindrical vertical apparatus, inside which are located contact devices (plates) through which the vapor moves up and the liquid moves down. Distillation columns of various sizes and configurations are used in almost all oil refining plants, the number of plates in them varies from 20 to 60. Heat is supplied to the lower part of the column and heat is removed from the upper part of the column, and therefore the temperature in the apparatus gradually decreases from the bottom to the top. As a result, the gasoline fraction is removed from the top of the column in the form of vapors, and the vapors of the kerosene and diesel fractions condense in the corresponding parts of the column and are removed, the fuel oil remains liquid and is pumped out from the bottom of the column.

2. Vacuum distillation
Vacuum distillation (Fig. 3,5,6) is intended for selection from fuel oil oil distillates at refineries of the fuel-oil profile, or a wide oil fraction (vacuum gas oil) at the refinery of the fuel profile. The remainder of the vacuum distillation is tar.
The need to select oil fractions under vacuum is due to the fact that at temperatures above 380 ° C, thermal decomposition of hydrocarbons begins. (cracking), and the end of boiling vacuum gas oil - 520°C or more. Therefore, the distillation is carried out at a residual pressure of 40-60 mm Hg. Art., which allows you to reduce the maximum temperature in the apparatus to 360-380°C.
The vacuum in the column is created using appropriate equipment, the key devices are steam or liquid ejectors(Fig. 7).

3. Stabilization and secondary distillation of gasoline
The gasoline fraction obtained at the atmospheric unit contains gases (mainly propane and butane) in a volume that exceeds the quality requirements and cannot be used either as a component of motor gasoline or as commercial straight-run gasoline. In addition, refinery processes aimed at increasing the octane number of gasoline and the production of aromatic hydrocarbons use narrow gasoline fractions as raw materials. This is the reason for the inclusion of this process in the technological scheme of oil refining (Fig. 4), in which liquefied gases are distilled off from the gasoline fraction, and it is distilled into 2-5 narrow fractions on the corresponding number of columns.

Products of primary oil refining are cooled in heat exchangers, in which they give off heat to the cold raw material entering for processing, due to which process fuel is saved, in water and air coolers and are taken out of production. A similar heat exchange scheme is used at other refinery units.

Modern primary processing plants are often combined and may include the above processes in various configurations. The capacity of such installations is from 3 to 6 million tons of crude oil per year.
Several primary processing units are being built at the plants in order to avoid a complete shutdown of the plant when one of the units is taken out for repairs.

Products of primary oil refining

*) - n.c. - the beginning of the boil
**) - k.k. - end of boil

Photographs of primary processing plants of various configurations

Fig.5. Vacuum distillation unit with a capacity of 1.5 million tons per year at the Turkmenbashi refinery under the project of Uhde.	Rice. 6. Vacuum distillation unit with a capacity of 1.6 million tons per year at the LUKOIL-PNOS refinery. In the foreground is a tube furnace (yellow).	Fig.7. Vacuum generating equipment from Graham. 3 ejectors are visible, into which vapors enter from the top of the column.

Sergey Pronin

Modern oil refining is characterized by multistage production of high quality products. In many cases, along with the main processes, preparatory and final processes are also carried out. The preparatory technological processes include: 1. desalting of oil before processing; 2. separation of narrow fractions from distillates of a wide fractional composition; 3. hydrotreatment of gasoline fractions before their catalytic reforming; 4. hydrodesulfurization of gas oil feedstock sent to catalytic cracking; 5. tar deasphalting; 6. hydrotreatment of kerosene distillate before its absorption separation, etc.

2nd stage, 1st stage Primary processing 3rd stage Secondary processing Reforming Desalination Fractionation Cracking 4th stage Refining of petroleum products Hydrotreating Selective Solvent Refining Dewaxing Hydrotreating

Stage 1: Desalting of oil The production cycle starts with CDU. This abbreviation stands for “electric desalination plant”. Desalting begins with the fact that the oil is taken from the factory tank, mixed with wash water, demulsifiers, alkali (if there are acids in the crude oil). Then the mixture is heated to 80-120°C and fed into an electric dehydrator. In an electrohydrator, under the influence of an electric field and temperature, water and inorganic compounds dissolved in it are separated from oil. The requirements for the desalination process are strict: no more than 3 - 4 mg / l of salts and about 0.1% of water should remain in the oil. Therefore, most often in production, a two-stage process is used, and after the first one, the oil enters the second electric dehydrator. After that, the oil is considered suitable for further processing and enters the primary distillation.

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates Primary oil refinery units form the basis of all technological processes of oil refineries. The quality and yields of the resulting fuel components, as well as raw materials for secondary and other oil refining processes, depend on the operation of these plants.

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates In industrial practice, oil is divided into fractions that differ in boiling point temperature limits: liquefied gas gasoline (automobile and aviation) jet fuel kerosene diesel fuel (diesel fuel), fuel oil Fuel oil is processed to obtain: paraffin, bitumen , liquid boiler fuel, oils.

Stage 2: Oil Refining The essence of the oil refining process is simple. Like all other compounds, each liquid petroleum hydrocarbon has its own boiling point, that is, the temperature above which it evaporates. The boiling point increases as the number of carbon atoms in the molecule increases. For example, benzene C 6 H 6 boils at 80.1 ° C, and toluene C 7 H 8 at 110.6 ° C.

Stage 2: Oil distillation For example, if you put oil in a distillation device, which is called a still, and start heating it, then as soon as the temperature of the liquid exceeds 80 ° C, all benzene will evaporate from it, and with it other hydrocarbons with close boiling points . Thus, a fraction is separated from the oil from the beginning of boiling to 80 ° C, or n. k. - 80 ° C, as it is customary to write in the literature on oil refining. If you continue heating and raise the temperature in the cube by another 25 ° C, then the next fraction will separate from the oil - C 7 hydrocarbons, which boil in the range of 80 -105 ° C. And so on, up to a temperature of 350 °C. It is undesirable to raise the temperature above this limit, since the remaining hydrocarbons contain unstable compounds, which, when heated, tar oil, decompose to carbon and can coke, clog all the equipment with tar.

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates The separation of oil into fractions is carried out at primary distillation units using heating, distillation, rectification, condensing and cooling processes. Direct distillation is carried out at atmospheric or slightly elevated pressure, and residues under vacuum. Atmospheric (AT) and vacuum tubular installations (VT) are built separately from each other or combined as part of one installation (AVT).

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates In modern refineries, instead of fractional distillation in batch stills, distillation columns are used. Above the cube in which the oil is heated, a high cylinder is attached, blocked by a multitude of distillation plates. Their design is such that the vapors of oil products rising upwards can partially condense, collect on these plates and, as the liquid phase accumulates on the plate, drain down through special drain devices. At the same time, vaporous products continue to bubble through the liquid layer on each plate.

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates The temperature in the distillation column decreases from the bottom to the very last, upper plate. If in the cube it is 380 ° C, then on the top plate it should not be higher than 35 -40 ° C in order to condense and not lose all C 5 hydrocarbons, without which commercial gasoline cannot be prepared. Uncondensed hydrocarbon gases C 1 -C 4 leave at the top of the column. Everything that can condense remains on the plates. Thus, it is enough to make taps at different heights in order to obtain oil distillation fractions, each of which boils within the specified temperature limits. The fraction has its own specific purpose and, depending on it, it can be wide or narrow, that is, boil away in the range of two hundred or twenty degrees.

Stage 2: Primary distillation of oil and secondary distillation of gasoline distillates Modern refineries usually operate atmospheric tubulars or atmospheric vacuum tubulars with a capacity of 6 to 8 million tons of processed oil per year. Usually there are two or three such installations at the plant. The first atmospheric column is a structure with a diameter of about 7 meters at the bottom and 5 meters at the top. The height of the column is 51 meters. Essentially, these are two cylinders stacked one on top of the other. Other columns are condensers, furnaces and heat exchangers

Stage 2: Primary distillation of crude oil and secondary distillation of gasoline distillates In terms of costs, the broader fractions obtained in the end, the cheaper they are. Therefore, oil was first distilled into broad fractions: gasoline fraction (straight-run gasoline, 40 -50 -140 -150 ° C). jet fuel fraction (140 -240 °С), diesel (240 -350 °С). oil distillation residue - fuel oil Currently, distillation columns separate oil into narrower fractions. And the narrower the factions want to get, the higher the columns should be. The more plates they should have, the more times the same molecules must, rising up from plate to plate, go from the gas phase to the liquid and back. This requires energy. It is brought to the cube of the column in the form of steam or flue gases.

Stage 3: Cracking of petroleum fractions In addition to desalting, dehydration and straight distillation, many refineries have another processing operation - secondary distillation. The task of this technology is to obtain narrow fractions of oil for further processing. The products of secondary distillation are usually gasoline fractions used to produce automotive and aviation fuels, as well as raw materials for the subsequent production of aromatic hydrocarbons - benzene, toluene and others.

Stage 3: Cracking of petroleum fractions Typical secondary distillation plants are very similar in appearance and operation to atmospheric tubular units, only their dimensions are much smaller. Secondary distillation completes the first stage of oil refining: from desalting to obtaining narrow fractions. At the 3rd stage of oil refining, in contrast to the physical processes of distillation, deep chemical transformations take place.

Stage 3: thermal cracking of oil fractions One of the most common technologies of this cycle is cracking (from the English word cracking - splitting) Cracking is a reaction of splitting the carbon skeleton of large molecules when heated and in the presence of catalysts. During thermal cracking, complex recombinations of fragments of broken molecules occur with the formation of lighter hydrocarbons. Under the influence of high temperature, long molecules, for example, C 20 alkanes, are split into shorter ones - from C 2 to C 18. (Hydrocarbons C 8 - C 10 are the gasoline fraction, C 15 - diesel) The reactions of cyclization and isomerization of oil hydrocarbons also occur

Stage 3: thermal cracking of oil fractions Cracking technologies allow increasing the yield of light oil products from 40-45% to 55-60%. Gasoline, kerosene, diesel fuel (solar) are made from these petroleum products.

Stage 3: catalytic cracking of petroleum fractions Catalytic cracking was discovered in the 30s of the 20th century. when it was noticed that contact with some natural aluminosilicates changes the chemical composition of thermal cracking products. Additional studies have led to two important results: 1. the mechanism of catalytic transformations has been established; 2. realized that it is necessary to specifically synthesize zeolite catalysts, and not look for them in nature.

Stage 3: catalytic cracking of petroleum fractions Mechanism of catalytic cracking: the catalyst sorbs on itself molecules that are able to dehydrogenate quite easily, that is, give off hydrogen; the resulting unsaturated hydrocarbons, having an increased adsorption capacity, come into contact with the active centers of the catalyst; as the concentration of unsaturated compounds increases, their polymerization occurs, resins appear - the precursors of coke, and then coke itself;

Stage 3: catalytic cracking of oil fractions, the released hydrogen takes an active part in other reactions, in particular hydrocracking, isomerization, etc., as a result of which the cracked product is enriched with hydrocarbons not only light, but also high-quality - isoalkanes, arenes, alkylarenes with boiling points of 80 - 195 ° C (this is the wide gasoline fraction, for the sake of which catalytic cracking of heavy raw materials is carried out).

Stage 3: catalytic cracking of petroleum fractions Typical parameters of catalytic cracking when operating on vacuum distillate (fr. 350 - 500 °C): temperature 450 - 480 °C pressure 0.14 - 0.18 MPa. The average capacity of modern plants is from 1.5 to 2.5 million tons, however, there are plants with a capacity of 4.0 million tons at the plants of the world's leading companies. As a result, hydrocarbon gases (20%), gasoline fraction (50%), diesel fraction (20%) are obtained. The rest is heavy gas oil or cracked residue, coke and losses.

Stage 3: catalytic cracking of petroleum fractions Microspherical cracking catalysts provide a high yield of light oil products (68–71 wt.%), depending on the brand of catalyst.

Reactor unit for catalytic cracking using Exxon technology. Mobil. On the right side is the reactor, to the left of it is the regenerator.

Stage 3: Reforming - (from the English reforming - to remake, improve) the industrial process of processing gasoline and naphtha oil fractions in order to obtain high-quality gasolines and aromatic hydrocarbons. Until the 1930s, reforming was a type of thermal cracking and was carried out at 540 o. C to obtain gasoline with an octane rating of 70 -72.

Stage 3: Reforming Since the 1940s, reforming has been a catalytic process, the scientific foundations of which were developed by N. D. Zelinsky, as well as V. I. Karzhev, B. L. Moldavsky. This process was first carried out in 1940 in the USA. It is carried out in an industrial plant with a heating furnace and at least 3-4 reactors at a temperature of 350-520 o. C, in the presence of various catalysts: platinum and polymetallic, containing platinum, rhenium, iridium, germanium, etc. .

Stage 3: Reforming is carried out under high pressure hydrogen, which is circulated through the heating furnace and reactors. These catalytic conversions allow the dehydrogenation of naphthenic hydrocarbons to aromatics. At the same time, the dehydrogenation of alkanes into the corresponding alkenes occurs, these latter are immediately cyclized into cycloalkanes, and the dehydrogenation of cycloalkanes into arenes occurs at an even greater rate. So, in the process of aromatization, a typical transformation is the following: n-heptane n-heptene methylcyclohexane toluene. As a result of reforming gasoline fractions of oil, 80-85% gasoline with an octane rating of 90-95, 1-2% hydrogen and the rest of gaseous hydrocarbons are obtained

Stage 4: Hydrotreatment - purification of petroleum products from organic sulfur, nitrogen and oxygen compounds using hydrogen molecules. As a result of hydrotreatment, the quality of oil products is improved, equipment corrosion is reduced, and air pollution is reduced. The hydrotreatment process has become very important due to the involvement in the processing of large quantities of sulphurous and high-sulphurous (more than 1.9% sulfur) types of oil.

Stage 4: Hydrotreatment When processing oil products on hydrogenating catalysts using aluminum, cobalt and molybdenum compounds at a pressure of 4 - 5 MPa and a temperature of 380 - 420 °C. several chemical reactions occur: Hydrogen combines with sulfur to form hydrogen sulfide (H 2 S). Some nitrogen compounds are converted to ammonia. Any metals contained in the oil are deposited on the catalyst. Some olefins and aromatics are saturated with hydrogen; in addition, naphthenes are hydrocracked to some extent and some methane, ethane, propane and butanes are formed.

Stage 4: Hydrotreatment Under normal conditions, hydrogen sulfide is in a gaseous state, and when the oil product is heated, it is released from it. It is taken up in water in reflux towers and then converted into either elemental sulfur or concentrated sulfuric acid. The sulfur content, especially in light oil products, can be reduced to thousandths. Why bring the content of impurities of organosulfur substances in gasoline to such a strict standard? It's all about later use. It is known, for example, that the more severe the catalytic reforming regime, the higher the yield of high-octane gasoline at a given octane number or the higher the octane number at a given catalyzate yield. As a result, the yield of "octane-tons" is increased - this is the name given to the product of the amount of reforming catalysate or any other component and its octane number.

Stage 4: Hydrotreating Refiners primarily care about increasing the octane-tons of the product compared to the raw material. Therefore, they are trying to tighten all secondary processes of oil refining. In reforming, hardness is determined by a decrease in pressure and an increase in temperature. At the same time, aromatization reactions proceed more fully and faster. But the increase in stiffness is limited by the stability of the catalyst and its activity.

Stage 4: Hydrotreating Sulfur, being a catalyst poison, poisons the catalyst as it accumulates on it. From this it is clear: the less it is in the raw material, the longer the catalyst will be active with increasing hardness. As in the rule of leverage: if you lose at the refinement stage, you win at the reforming stage. Usually, not all, for example, the diesel fraction is subjected to hydrotreating, but only a part of it, since this process is quite expensive. In addition, it has one more drawback: this operation practically does not change the hydrocarbon composition of the fractions.

Stage 4: SELECTIVE CLEANING of petroleum products. carried out by solvent extraction of harmful impurities from petroleum fractions to improve their physical, chemical and operational characteristics; one of the main technological processes for the production of lubricating oils from petroleum feedstocks. Selective purification is based on the ability of polar solvents to selectively (selectively) dissolve polar or polarizable components of raw materials, polycyclic aromatic hydrocarbons and high molecular weight resinous asphaltene substances.

Oil is a mineral that is an oily liquid insoluble in water, which can be either almost colorless or dark brown. The properties and methods of oil refining depend on the percentage of predominantly hydrocarbons in its composition, which varies in different fields.

So, in the Sosninskoye deposit (Siberia), alkanes (paraffin group) occupy a share of 52 percent, cycloalkanes - about 36%, aromatic hydrocarbons - 12 percent. And, for example, in the Romashkinskoye deposit (Tatarstan), the share of alkanes and aromatic hydrocarbons is higher - 55 and 18 percent, respectively, while cycloalkanes have a share of 25 percent. In addition to hydrocarbons, this raw material may include sulfur, nitrogen compounds, mineral impurities, etc.

Oil was first "refined" in 1745 in Russia

In its raw form, this natural resource is not used. To obtain technically valuable products (solvents, motor fuels, components for chemical industries), oil is processed using primary or secondary methods. Attempts to transform this raw material were made as early as the middle of the eighteenth century, when, in addition to candles and torches used by the population, "garne oil" was used in the lamps of a number of churches, which was a mixture of vegetable oil and refined oil.

Oil refining options

Refining is often not included directly in oil refining processes. It is rather a preliminary stage, which may consist of:

Chemical cleaning, when oil is treated with oleum and concentrated sulfuric acid. This removes aromatic and unsaturated hydrocarbons.

adsorption cleaning. Here, resins and acids can be removed from oil products by treatment with hot air or by passing oil through an adsorbent.

Catalytic purification - mild hydrogenation to remove nitrogen and sulfur compounds.

Physical and chemical cleaning. In this case, excess components are selectively isolated by means of solvents. For example, the polar solvent phenol is used to remove nitrogenous and sulfurous compounds, and non-polar solvents - butane and propane - release tars, aromatic hydrocarbons, etc.

No chemical changes...

Oil processing through primary processes does not involve chemical transformations of the feedstock. Here, the mineral is simply divided into its constituent components. The first oil distillation device was invented in 1823 in the Russian Empire. The Dubinin brothers guessed to put the boiler in a heated oven, from where a pipe went through a barrel of cold water into an empty container. In the furnace boiler, the oil was heated, passed through the “cooler” and precipitated.

Modern methods of preparation of raw materials

Today, at oil refineries, oil refining technology begins with additional purification, during which the product is dehydrated on ELOU devices (electric desalination plants), freed from mechanical impurities and light-type carbohydrates (C1 - C4). Then the raw material can be sent to atmospheric distillation or vacuum distillation. In the first case, the factory equipment, according to the principle of operation, resembles that which was used back in 1823.

Only the oil refining unit itself looks different. At the enterprise there are furnaces resembling windowless houses in size, made of the best refractory bricks. Inside them are many kilometers of pipes, in which oil moves at high speed (2 meters per second) and is heated up to 300-325 C by a flame from a large nozzle (at higher temperatures, hydrocarbons simply decompose). Today, the pipe for condensation and cooling of vapors is replaced by distillation columns (they can be up to 40 meters in height), where the vapors are separated and condensed, and entire towns from different reservoirs are built to receive the resulting products.

What is material balance?

Oil refining in Russia gives different material balances during the atmospheric distillation of raw materials from one or another field. This means that different proportions can be obtained at the output for different fractions - gasoline, kerosene, diesel, fuel oil, associated gas.

For example, for West Siberian oil, the gas yield and losses are one percent each, gasoline fractions (released at temperatures from about 62 to 180 C) occupy a share of about 19%, kerosene - about 9.5%, diesel fraction - 19% , fuel oil - almost 50 percent (is released at temperatures from 240 to 350 degrees). The resulting materials are almost always subjected to additional processing, since they do not meet the operational requirements for the same machine motors.

Production with less waste

Vacuum oil refining is based on the principle of boiling substances at a lower temperature with a decrease in pressure. For example, some hydrocarbons in oil only boil at 450°C (atmospheric pressure), but they can be made to boil at 325°C if the pressure is lowered. Vacuum processing of raw materials is carried out in rotary vacuum evaporators, which increase the speed of distillation and make it possible to obtain ceresin, paraffins, fuel, oils from fuel oil, and use the heavy residue (tar) further for the production of bitumen. Vacuum distillation, compared to atmospheric processing, produces less waste.

Recycling allows you to get high-quality gasoline

The secondary oil refining process was invented in order to get more motor fuel from the same feedstock by influencing the molecules of petroleum hydrocarbons, which acquire formulas more suitable for oxidation. Recycling includes various types of so-called "cracking", including hydrocracking, thermal and catalytic options. This process was also originally invented in Russia, in 1891, by engineer V. Shukhov. It is the breakdown of hydrocarbons into forms with fewer carbon atoms per molecule.

Oil and gas processing at 600 degrees Celsius

The principle of operation of cracking plants is approximately the same as that of atmospheric pressure vacuum plants. But here, the processing of raw materials, which is most often represented by fuel oil, is carried out at temperatures close to 600 C. Under such influence, the hydrocarbons that make up the fuel oil mass break down into smaller ones, which make up the same kerosene or gasoline. Thermal cracking is based on high temperature treatment and produces gasoline with a large amount of impurities, catalytic cracking is also based on heat treatment, but with the addition of catalysts (for example, special clay dust), which allows you to get more good quality gasoline.

Hydrocracking: main types

Oil production and refining today can include various types of hydrocracking, which is a combination of hydrotreating processes, splitting large hydrocarbon molecules into smaller ones, and saturating unsaturated hydrocarbons with hydrogen. Hydrocracking can be light (pressure 5 MPa, temperature about 400 C, one reactor is used, mainly diesel fuel and material for catalytic cracking are obtained) and hard (pressure 10 MPa, temperature about 400 C, there are several reactors, diesel, gasoline and kerosene are obtained). fractions). Catalytic hydrocracking makes it possible to produce a range of oils with high viscosity coefficients and a low content of aromatic and sulphurous hydrocarbons.

Secondary oil refining, in addition, can use the following technological processes:

Visbreaking. In this case, at temperatures up to 500 C and pressures ranging from half to three MPa, secondary asphaltenes, hydrocarbon gases, gasoline are obtained from raw materials due to the splitting of paraffins and naphthenes.

Coking of heavy oil residues is a deep processing of oil, when raw materials are processed at temperatures close to 500 C under a pressure of 0.65 MPa to obtain gas oil components and petroleum coke. The process steps end in a "coke cake" preceded (in reverse order) by compaction, polycondensation, aromatization, cyclization, dehydrogenation and cracking. In addition, the product must also be dried and calcined.

Reforming. This method of processing petroleum products was invented in Russia in 1911 by engineer N. Zelinsky. Today, catalytic reforming is used to produce high-quality aromatic hydrocarbons and gasolines from naphtha and gasoline fractions, as well as hydrogen-containing gas for further processing in hydrocracking.

Isomerization. The processing of oil and gas in this case involves the production of an isomer from a chemical compound due to changes in the carbon skeleton of the substance. So, high-octane components are isolated from low-octane oil components to produce commercial gasoline.

Alkylation. This process is based on the incorporation of alkyl substituents into the organic molecule. Thus, components for high-octane gasolines are obtained from hydrocarbon gases of an unsaturated nature.

Striving for European standards

The technology of oil and gas processing at refineries is constantly being improved. Thus, domestic enterprises noted an increase in the efficiency of processing raw materials in terms of the depth of processing, an increase in the selection of light oil products, a decrease in irretrievable losses, etc. The plans of plants for the 10-20s of the twenty-first century include a further increase in the depth of processing (up to 88 percent) , improving the quality of manufactured products to European standards, reducing the technogenic impact on the environment.

Introduction

I. Primary oil refining

1. Secondary distillation of gasoline and diesel fractions

1.1 Secondary distillation of the gasoline fraction

1.2 Secondary distillation of the diesel fraction

II. Thermal processes of oil refining technology

2. Theoretical foundations for controlling the processes of delayed coking and coking in the coolant layer

2.1 Delayed coking processes

2.2 Coking in the heat carrier layer

III. Thermocatalytic and thermohydrocatalytic processes technology

oil refining

3. Hydrotreating of kerosene fractions

IV. Gas processing technologies

4. Processing of refinery gases - absorption gas fractionation units (AGFU) and gas fractionation units (GFU)

4.1 Gas fractionation plants (HFCs)

4.2 Absorption and gas fractionation units (AGFU)

Conclusion

Bibliography

Introduction

The oil industry today is a large national economic complex that lives and develops according to its own laws. What does oil mean today for the national economy of the country? These are: raw materials for petrochemicals in the production of synthetic rubber, alcohols, polyethylene, polypropylene, a wide range of various plastics and finished products from them, artificial fabrics; a source for the production of motor fuels (gasoline, kerosene, diesel and jet fuels), oils and lubricants, as well as boiler and furnace fuel (fuel oil), building materials (bitumen, tar, asphalt); raw material for obtaining a number of protein preparations used as additives in livestock feed to stimulate its growth.

Currently, the oil industry of the Russian Federation ranks 3rd in the world. The oil complex of Russia includes 148 thousand oil wells, 48.3 thousand km of main oil pipelines, 28 oil refineries with a total capacity of more than 300 million tons per year of oil, as well as a large number of other production facilities.

About 900,000 workers are employed at the enterprises of the oil industry and its service industries, including about 20,000 people in the field of science and scientific services.

Industrial organic chemistry has come a long and difficult path of development, during which its raw material base has changed dramatically. Starting with the processing of plant and animal raw materials, it then transformed into coal or coke chemistry (utilizing coal coking waste), in order to eventually turn into modern petrochemistry, which has long been not content with only oil refining waste. For the successful and independent functioning of its main industry - heavy, that is, large-scale, organic synthesis, the pyrolysis process was developed, around which modern olefin petrochemical complexes are based. Basically, they receive and then process lower olefins and diolefins. The raw material base of pyrolysis can vary from associated gases to naphtha, gas oil and even crude oil. Initially intended only for the production of ethylene, this process is now also a large-scale supplier of propylene, butadiene, benzene and other products.

Oil is our national wealth, the source of the country's power, the foundation of its economy.

oil and gas processing technology

I . Primary oil refining

1. Secondary distillation of gasoline and diesel fractions

Secondary distillation - separation of the fractions obtained during the primary distillation into narrower cuts, each of which is then used for its own purpose.

At refineries, the broad gasoline fraction, diesel fraction (when receiving raw materials from the paraffin adsorption recovery unit), oil fractions, etc. are subjected to secondary distillation. The process is carried out on separate installations or blocks that are part of the AT and AVT installations.

Oil distillation - the process of separating it into fractions according to boiling points (hence the term "fractionation") - is the basis of oil refining and the production of motor fuel, lubricating oils and various other valuable chemical products. The primary distillation of oil is the first stage in the study of its chemical composition.

The main fractions isolated during the primary distillation of oil:

1. Gasoline fraction- oil shoulder strap with a boiling point from n.c. (beginning of boiling, individual for each oil) up to 150-205 0 C (depending on the technological purpose of obtaining auto-, aviation-, or other special gasoline).

This fraction is a mixture of alkanes, naphthenes and aromatic hydrocarbons. All these hydrocarbons contain from 5 to 10 C atoms.

2. Kerosene fraction- oil cut with a boiling point from 150-180 0 C to 270-280 0 C. This fraction contains C10-C15 hydrocarbons.

It is used as a motor fuel (tractor kerosene, diesel fuel component), for household needs (lighting kerosene), etc.

3. Gas oil fraction- boiling point from 270-280 0 C to 320-350 0 C. This fraction contains C14-C20 hydrocarbons. Used as diesel fuel.

4. fuel oil- the residue after distillation of the above fractions with a boiling point above 320-350 0 С.

Fuel oil can be used as a boiler fuel, or be subjected to further processing - either distillation under reduced pressure (in vacuum) with the selection of oil fractions or a wide fraction of vacuum gas oil (which, in turn, serves as a feedstock for catalytic cracking in order to obtain a high-octane component of gasoline), or cracking.

5. Tar- almost solid residue after distillation of oil fractions from fuel oil. So-called residual oils and bitumen are obtained from it, from which asphalt is obtained by oxidation, which is used in the construction of roads, etc. From tar and other residues of secondary origin, coke used in the metallurgical industry can be obtained by coking.

1 .1 Secondary distillation of gasoline fraction

Secondary distillation of gasoline distillate is either an independent process or is part of a combined plant that is part of the refinery. At modern plants, the installation of the secondary distillation of gasoline distillate is designed to obtain narrow fractions from it. These fractions are further used as feedstock for catalytic reforming - a process that produces individual aromatic hydrocarbons - benzene, toluene, xylenes, or gasoline with a higher octane number. In the production of aromatic hydrocarbons, the initial gasoline distillate is divided into fractions with boiling points: 62–85°C (benzene), 85–115 (120)°C (toluene) and 115 (120)–140°C (xylene).

Gasoline fraction is used to obtain various grades of motor fuel. It is a mixture of various hydrocarbons, including straight and branched alkanes. The combustion characteristics of unbranched alkanes are not ideally suited to internal combustion engines. Therefore, the gasoline fraction is often thermally reformed to convert unbranched molecules into branched ones. Before use, this fraction is usually mixed with branched alkanes, cycloalkanes and aromatic compounds obtained from other fractions by catalytic cracking or reforming.

The quality of gasoline as a motor fuel is determined by its octane number. It indicates the percentage by volume of 2,2,4-trimethylpentane (isooctane) in a mixture of 2,2,4-trimethylpentane and heptane (straight chain alkane) that has the same detonation combustion characteristics as the test gasoline.

A poor motor fuel has an octane rating of zero, while a good fuel has an octane rating of 100. The octane rating of the gasoline fraction obtained from crude oil is usually less than 60. The combustion characteristics of gasoline are improved by the addition of an antiknock additive, which is tetraethyl lead (IV) , Рb (С 2 Н 5) 4 . Tetraethyl lead is a colorless liquid obtained by heating chloroethane with an alloy of sodium and lead:

During the combustion of gasoline containing this additive, particles of lead and lead oxide (II) are formed. They slow down certain stages of combustion of gasoline fuel and thus prevent its detonation. Together with tetraethyl lead, 1,2-dibromoethane is added to gasoline. It reacts with lead and lead(II) to form lead(II) bromide. Since lead(II) bromide is a volatile compound, it is removed from the car engine in the exhaust gases. Gasoline distillate of a wide fractional composition, for example, from the initial boiling point to 180 ° C, is pumped through the heat exchangers and fed into the first coil of the furnace, and then into the distillation column. The head product of this column is the n fraction. k. - 85 °C, having passed the air-cooling apparatus and the refrigerator, it enters the receiver. Part of the condensate is pumped as irrigation to the top of the column, and the rest - to another column. The heat supply to the lower part of the column is carried out by circulating phlegm (fraction 85-180 ° C), pumped through the second coil of the furnace and fed to the bottom of the column. The remainder from the bottom of the column is sent by the pump to another column.

Leaving from the top of the column, the vapors of the head fraction (n. to. - 62 ° C) are condensed in the air cooler; the condensate cooled in the water cooler is collected in the receiver. From here, the condensate is pumped to the tank, and part of the fraction serves as irrigation for the column. The residual product - a fraction of 62-85 ° C - after leaving the column from the bottom is sent by a pump through a heat exchanger and coolers to the tank. As the upper product of the column, a fraction of 85-120 ° C is obtained, which, after passing through the apparatus, enters the receiver. Part of the condensate is returned to the top of the column as irrigation, and its balance amount is removed from the installation by a pump to the tank.

The Russian Federation is one of the world leaders in oil extraction and production. More than 50 enterprises operate in the state, the main tasks of which are oil refining and petrochemistry. Among them are Kirishi NOS, Omsk Oil Refinery, Lukoil-NORSI, RNA, YaroslavNOS and so on.

At the moment, most of them are connected to well-known oil and gas companies such as Rosneft, Lukoil, Gazprom and Surgutneftegaz. The period of operation of such production is about 3 years.

Main products of oil refining These are gasoline, kerosene and diesel fuel. Now more than 90% of all mined black gold is used to produce fuel: aviation, jet, diesel, furnace, boiler, as well as lubricating oils and raw materials for future chemical processing.

Oil refining technology

Oil refining technology consists of several stages:

• separation of products into fractions that differ in boiling point;


• processing of these associations with the help of chemical compounds and the production of marketable petroleum products;


• mixing components using a variety of mixtures.

The branch of science that is devoted to the processing of combustible minerals is petrochemistry. She studies the processes of obtaining products from black gold and final chemical workings. These include alcohol, aldehyde, ammonia, hydrogen, acid, ketone, and the like. To date, only 10% of the produced oil is used as a raw material for petrochemicals.

Basic Refining Processes

Oil refining processes are divided into primary and secondary. The former do not imply a chemical change in black gold, but ensure its physical separation into fractions. The task of the latter is to increase the volume of produced fuel. They contribute to the chemical transformation of hydrocarbon molecules, which is part of the oil, into simpler compounds.

Primary processes occur in three stages. The initial one is the preparation of black gold. It undergoes additional purification from mechanical impurities, removal of light gases and water is carried out using modern electric desalination equipment.

This is followed by atmospheric distillation. The oil moves to the distillation column, where it is divided into fractions: gasoline, kerosene, diesel, and finally into fuel oil. The quality that the products have at this stage of processing does not correspond to the commercial characteristics, therefore, the fractions are subjected to secondary processing.

Secondary processes can be divided into several types:

• deepening (catalytic and thermal cracking, visbreaking, slow coking, hydrocracking, bitumen production, etc.);


• refining (reforming, hydrotreating, isomerization, etc.);


• other operations for the production of oil and aromatic hydrocarbons, as well as alkylation.

Reforming is applied to the gasoline fraction. As a result, it is saturated with aromatic mixtures. The extracted raw material is used as an element for the production of gasoline.

Catalytic cracking is used to break down molecules of heavy gases, which are then used to release fuel.

Hydrocracking is a method of splitting gas molecules in an excess of hydrogen. As a result of this process, diesel fuel and elements for gasoline are obtained.

Coking is an operation for the extraction of petroleum cokes from the heavy fraction and residues of the secondary process.

Hydrocracking, hydrogenation, hydrotreatment, hydrodearomatization, hydrodewaxing are all hydrogenation processes in oil refining. Their distinguishing characteristic is the carrying out of catalytic transformations in the presence of hydrogen or a gas that contains water.

Modern installations for the primary industrial refining of oil are often combined and can perform some secondary processes in a variety of volumes.

Oil refining equipment

Oil refining equipment is:

• generators;


• reservoirs;


• filters;


• liquid and gas heaters;


• incinerators (devices for thermal waste disposal);


• flare systems;


• gas compressors;


• steam turbines;


• heat exchangers;


• stands for hydraulic testing of pipelines;


• pipes;


• fittings and the like.

In addition, the enterprises use technological furnaces for oil refining. They are designed to heat the process medium using the heat released during fuel combustion.

There are two types of these units: tube furnaces and devices for burning liquid, solid and gaseous production residues.

The basics of oil refining are that, first of all, production begins with the distillation of oil and its formation into separate fractions.

Then the main part of the obtained compounds is converted into more necessary products by changing their physical characteristics and molecular structure under the influence of cracking, reforming and other operations that are related to secondary processes. Further, oil products sequentially undergo various types of purification and separation.

Large refineries are engaged in fractionation, conversion, processing and blending of black gold with lubricants. In addition, they produce heavy fuel oil and asphalt, and can also carry out further distillation of petroleum products.

Design and construction of oil refinery

To begin with, it is necessary to carry out the design and construction of oil refining. This is a rather complex and responsible process.

The design and construction of oil refining takes place in several stages:

• formation of the main goals and objectives of the enterprise and investment analysis;


• selection of a territory for production and obtaining a permit for the construction of a plant;


• the project of the oil refining complex itself;


• collection of necessary devices and mechanisms, construction and installation, as well as commissioning;


• the final stage is the commissioning of the oil producing enterprise.

The production of products from black gold occurs with the help of specialized mechanisms.

Modern technologies of oil refining at the exhibition

The oil and gas industry is widely developed on the territory of the Russian Federation. Therefore, the question arises of creating new industries and improving and modernizing technical equipment. In order to bring the Russian oil and gas industry to a new, higher level, an annual exhibition of scientific achievements in this field is held. "Naftogaz".

Exposition "Neftegaz" will be distinguished by its scale and a large number of invited companies. Among them are not only popular domestic firms, but also representatives of other states. They will demonstrate their achievements, innovative technologies, fresh business projects and the like.

In addition, the exhibition will feature refined oil products, alternative fuels and energy, modern equipment for enterprises, and so on.

As part of the event, it is planned to hold various conferences, seminars, presentations, discussions, master classes, lectures and discussions.

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