Oil refining technologies are typical for modern oil refining. Brief description of the main technological processes of fuel production Modern methods of deep oil refining

Vladimir Khomutko

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Modern technologies for deepening oil refining

In strategic terms, the main goals of modernizing Russian oil refining are:

• maximizing the production of fuels that meet the Euro-5 standard;
• minimizing the output of fuel oil.

And how advanced oil refining should develop is also clear - it is necessary to build and put into operation new conversion processes in order to almost double their annual capacity: from 72 to 136 million tons.

For example, at the enterprises of the world leader in the oil refining industry - the USA, the share of processes that deepen refining is more than 55 percent, but in our country it is only 17 percent.

Changing this situation is possible, but with the help of what technologies? Using the classic set of processes is a long and very expensive path. At the present stage, the most effective technologies that could be applied at every Russian refinery are urgently needed. The search for such solutions should be carried out taking into account the specific properties of heavy oil residues, such as an increased content of asphaltene and resinous substances and a high level of coking.

It is these properties of residues that indirectly push specialists to the conclusion that classical technologies of heavy residues (for example, coking, deasphalting and thermal cracking) are limited in their ability to select light distillates, which means that deepening oil refining with their help will be insufficient.

Available modern technologies

The main deepening technologies are based on the process of delayed coking of tars, which ensure the maximum yield of distillates (from 60 to 80 percent of the total volume of processed raw materials). In this case, the resulting fractions belong to middle and gas oil distillates. Medium fractions are sent for hydrotreating to produce diesel fuels, and heavy gas oil fractions are subjected to catalytic processing.

If we take countries such as Canada and Venezuela, they have been using delayed coking for more than two decades as a basic process for the commercial processing of heavy grade oils. However, for raw materials with a high sulfur content, coking is not applicable for environmental reasons. In addition, high-sulfur coke produced in colossal volumes has no effective use as a fuel, and subjecting it to desulfurization is simply unprofitable.

Russia doesn’t need coke of poor quality, especially in such quantities. In addition, delayed coking is a very energy-intensive process, harmful from an environmental point of view and unprofitable at low processing capacities. Due to these factors, it is necessary to find other deepening technologies.

Hydrocracking and gasification are the most expensive deep oil refining processes, so they will not be used at Russian refineries in the near future.

Therefore, we will not pay attention to them in this article. Russia needs the least capital-intensive, but quite effective conversion technologies.

The search for such technological solutions has been going on for a long time, and the main task of such a search is to obtain qualified residual products.

These are:

• high-melting pitch;
• "liquid coke";
• various brands of bitumen.

In addition, the yield of residues must be minimal in order for its processing through coking, gasification and hydrocracking to be profitable.

Also, one of the criteria for choosing a method for secondary advanced processing of petroleum residues is to obtain a sought-after high-quality product without losing the effectiveness of the technology itself. In our country, such a product, without a doubt, is high-quality road bitumen, since the condition of Russian roads is an eternal problem.

Therefore, if it is possible to select and implement an effective process for obtaining middle distillates and residues in the form of high-quality bitumen, this will make it possible to simultaneously solve the problem of deepening oil refining and provide the road construction industry with a high-quality residual product.

Among such technological processes that can be implemented at Russian processing enterprises, the following techniques are worthy of attention:

This is a well-known technological process used in the production of bitumen and tar. It is worth saying right away that approximately 80-90 percent of tars obtained by vacuum distillation of fuel oil do not meet the quality requirements for commercial bitumen, and their further processing using oxidative processes is necessary.

As a rule, before oxidation, tars are subjected to additional visbreaking in order to reduce the viscosity of the resulting boiler fuel, as well as to reduce the concentration of difficult-to-oxidize paraffins in the bitumen raw material.

If we talk about the vacuum gas oils obtained using this process, then they are characterized by:

• high density (more than 900 kilograms per cubic meter);
• high degree of viscosity;
• high values ​​of pour point (often more than thirty to forty degrees Celsius).

Such highly viscous and generally highly paraffinic gas oils are essentially intermediates that must be subjected to further catalytic processing. The bulk of the resulting tars is boiler fuel grade M-100.

Based on the above, vacuum processing of fuel oil no longer satisfies modern requirements for processes that are designed to deepen oil refining, as a result of which it should not be considered as a basic process capable of radically increasing GOR.

Propane deasphalting is typically used to produce high-index oils.

Deasphalting of tars with gasoline is used mainly for the production of raw materials, which are then used for the production of bitumen, although the asphalt phase released in this case does not always have the properties necessary to obtain commercial bitumen of the required quality. In this regard, the resulting asphaltite must be additionally subjected to either oxidation or dilution with an oil phase.

The light phase of this technological process is deasphalting. Its performance is even worse than that of vacuum gas oil:

• density value - more than 920 kilograms per cubic meter;
• pour point - more than forty degrees Celsius;
• higher viscosity value.

All this requires additional catalytic processing. In addition, deasphalted oil, due to its high viscosity, is very difficult to pump.

But the biggest problem with deasphalting is its high energy intensity, which is why the size of capital investments, compared to vacuum distillation, more than doubles.

The bulk of the resulting asphaltite requires additional processing using conversion processes: delayed coking or gasification.

In connection with all of the above, deasphalting also does not meet the basic requirements for technology designed to simultaneously deepen oil refining and obtain high-quality road bitumen, therefore it is also not suitable as an effective technology for increasing gas pressure ratio.

Visbreaking of fuel oil

This technical process is experiencing a rebirth and is becoming more and more in demand.

If previously visbreaking was used to reduce the viscosity of tars, then at the present stage of technology development it is becoming the main process that deepens oil refining. Almost all the largest companies in the world (Chioda, Shell, KBR, Foster Wuiller, UOP, and so on) have recently developed several original technological solutions.

The main advantages of these modern thermal processes are:

• simplicity;
• high degree of reliability;
• low cost of necessary equipment;
• increase in the yield of middle distillates obtained from heavy oil residues by 40 - 60 percent.

In addition, modern visbreaking makes it possible to obtain high-quality road bitumen and energy fuel such as “liquid coke”.

For example, such large corporations as Chioda and Shell send heavy gas oils (both vacuum and atmospheric) to hard cracking furnaces, which eliminates the release of fractions whose boiling point is more than 370 degrees Celsius. In the resulting products, only gasoline and diesel distillates and a very heavy residue remain, but there are no heavy types of gas oils at all!

Technology "Visbreaking - TERMAKAT"

This modern technology makes it possible to obtain from 88 to 93 percent of diesel and gasoline distillates from processed fuel oil.

When developing the Visbreaking-TERMAKAT technology, it was possible to control two parallel processes at once: thermal destruction and thermopolycondensation. In this case, destruction occurs in a prolonged mode, and thermopolycondensation occurs in a delayed mode.

Oil is a mineral that is a water-insoluble oily liquid that can be 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.

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

Oil was first “refined” in 1745 in Russia

This natural resource is not used in its raw form. To obtain technically valuable products (solvents, motor fuels, components for chemical production), oil is processed using primary or secondary methods. Attempts to transform this raw material were made back in the mid-eighteenth century, when, in addition to candles and torches used by the population, “garnish oil,” which was a mixture of vegetable oil and refined petroleum, was used in the lamps of a number of churches.

Oil purification options

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

Chemical refining, when oil is exposed to oleum and concentrated sulfuric acid. This removes aromatic and unsaturated hydrocarbons.

Adsorption cleaning. Here, tars and acids can be removed from petroleum products by treatment with hot air or by passing the oil through an adsorbent.

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

Physico-chemical cleaning. In this case, excess components are selectively released using solvents. For example, the polar solvent phenol is used to remove nitrogen and sulfur compounds, and non-polar solvents - butane and propane - release tars, aromatic hydrocarbons, etc.

No chemical changes...

Oil refining through primary processes does not involve chemical transformations of the feedstock. Here the mineral is simply divided into its component components. The first device for distilling oil was invented in 1823, in the Russian Empire. The Dubinin brothers thought of placing the boiler in a heated furnace, from where a pipe ran through a barrel of cold water into an empty container. In the furnace boiler, the oil was heated, passed through the “refrigerator” and settled.

Modern methods of preparing raw materials

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

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

What is material balance?

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

For example, for West Siberian oil, gas yield and losses are one percent each, respectively, 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 (released at temperatures from 240 to 350 degrees). The resulting materials are almost always subject to additional processing, since they do not meet the operational requirements for the same machine engines.

Production with less waste

Vacuum oil refining is based on the principle of substances boiling at a lower temperature when pressure decreases. For example, some hydrocarbons in oil boil only 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 distillation speed and make it possible to obtain ceresins, paraffins, fuel, oils from fuel oil, and then use the heavy residue (tar) for the production of bitumen. Vacuum distillation, compared to atmospheric processing, produces less waste.

Recycling allows us to obtain high-quality gasoline

The secondary oil refining process was invented in order to obtain more motor fuel from the same feedstock by influencing the molecules of petroleum hydrocarbons, which acquire formulas more suitable for oxidation. Recycling includes different 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 involves the breakdown of hydrocarbons into forms with fewer carbon atoms per molecule.

Oil and gas processing at 600 degrees Celsius

The operating principle of cracking plants is approximately the same as that of atmospheric pressure installations in vacuum production. 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 this 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 processing at high temperatures and produces gasoline with a large number of impurities, catalytic cracking is also based on temperature treatment, but with the addition of catalysts (for example, special clay dust), which allows you to obtain more gasoline of good quality.

Hydrocracking: main types

Oil production and refining today may involve various types of hydrocracking, which is a combination of hydrotreating processes, the splitting of large hydrocarbon molecules into smaller ones and the saturation of 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, several reactors, diesel, gasoline and kerosene are obtained factions). Catalytic hydrocracking makes it possible to produce a number of oils with high viscosity coefficients and low content of aromatic and sulfur hydrocarbons.

Recycling of oil, 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, and gasoline are obtained from the raw material by splitting paraffins and naphthenes.

Coking of heavy oil residues is a deep oil refining, when the raw material is processed at temperatures close to 500 C under a pressure of 0.65 MPa to produce gas oil components and petroleum coke. The process steps culminate in a “coke cake”, preceded (in reverse order) by densification, 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 obtain high-quality aromatic hydrocarbons and gasolines, as well as hydrogen-containing gas from naphtha and gasoline fractions, for subsequent processing in hydrocracking.

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

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

Striving for European standards

Oil and gas processing technology at refineries is constantly being improved. Thus, at domestic enterprises there has been an increase in the efficiency of processing raw materials in terms of parameters: depth of processing, increased selection of light petroleum products, reduction of irreversible losses, etc. Plant plans 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.

Oil refining is a rather complex process that requires the involvement of... Many products are obtained from extracted natural raw materials - different types of fuel, bitumen, kerosene, solvents, lubricants, petroleum oils and others. Oil refining begins with the transportation of hydrocarbons to the plant. The production process occurs in several stages, each of which is very important from a technological point of view.

Recycling process

The process of oil refining begins with its specialized preparation. This is caused by the presence of numerous impurities in natural raw materials. An oil deposit contains sand, salts, water, soil, and gaseous particles. Water is used to extract large quantities of products and preserve energy resource deposits. This has its advantages, but significantly reduces the quality of the resulting material.

The presence of impurities in petroleum products makes it impossible to transport them to the plant. They provoke the formation of plaque on heat exchangers and other containers, which significantly reduces their service life.

Therefore, the extracted materials undergo complex cleaning - mechanical and fine. At this stage of the production process, the resulting raw materials are separated into oil and. This happens using special oil separators.

To purify raw materials, they are generally kept in hermetically sealed containers. To activate the separation process, the material is exposed to cold or high temperature. Electric desalting plants are used to remove salts contained in raw materials.

How does the process of separating oil and water occur?

After initial purification, a sparingly soluble emulsion is obtained. It is a mixture in which particles of one liquid are evenly distributed in the second. On this basis, 2 types of emulsions are distinguished:

• hydrophilic. It is a mixture where oil particles are in water;
• hydrophobic. The emulsion consists mainly of oil with water particles in it.

The process of breaking the emulsion can occur mechanically, electrically or chemically. The first method involves settling the liquid. This happens under certain conditions - heating to a temperature of 120-160 degrees, increasing pressure to 8-15 atmospheres. Delamination of the mixture usually occurs within 2-3 hours.

In order for the emulsion separation process to be successful, it is necessary to prevent water evaporation. Also, the separation of pure oil is carried out using powerful centrifuges. The emulsion is divided into fractions when it reaches 3.5-50 thousand rpm.

The use of a chemical method involves the use of special surfactants called demulsifiers. They help dissolve the adsorption film, as a result of which the oil is cleared of water particles. The chemical method is often used in conjunction with the electrical method. The last cleaning method involves exposing the emulsion to electric current. It provokes the union of water particles. As a result, it is easier to remove from the mixture, resulting in oil of the highest quality.

Primary processing

Oil production and refining occurs in several stages. A peculiarity of the production of various products from natural raw materials is that even after high-quality purification, the resulting product cannot be used for its intended purpose.

The starting material is characterized by the content of various hydrocarbons, which differ significantly in molecular weight and boiling point. It contains substances of naphthenic, aromatic, and paraffin nature. The feedstock also contains sulfur, nitrogen and oxygen compounds of the organic type, which must also be removed.

All existing methods of oil refining are aimed at separating it into groups. During the production process, a wide range of products with different characteristics are obtained.

Primary processing of natural raw materials is carried out based on the different boiling temperatures of its constituent parts. To carry out this process, specialized installations are used that make it possible to obtain various petroleum products - from fuel oil to tar.

If you process natural raw materials in this way, you will not be able to obtain material ready for further use. Primary distillation is aimed only at determining the physical and chemical properties of oil. After this, the need for further processing can be determined. They also establish the type of equipment that needs to be used to perform the required processes.

Primary oil refining

Oil distillation methods

The following methods of oil refining (distillation) are distinguished:

• single evaporation;
• repeated evaporation;
• distillation with gradual evaporation.

The flash evaporation method involves processing oil under high temperature at a given value. As a result, vapors are formed that enter a special apparatus. It is called an evaporator. In this cylindrical device, vapors are separated from the liquid fraction.

With repeated evaporation, the raw material is subjected to processing, in which the temperature is increased several times according to a given algorithm. The latter distillation method is more complex. Oil refining with gradual evaporation implies a smooth change in the main operating parameters.

Distillation equipment

Industrial oil refining is carried out using several devices.

Tube furnaces. In turn, they are also divided into several types. These are atmospheric, vacuum, atmospheric-vacuum furnaces. Using the first type of equipment, shallow processing of petroleum products is carried out, which makes it possible to obtain fuel oil, gasoline, kerosene and diesel fractions. In vacuum furnaces, as a result of more efficient operation, raw materials are divided into:

• tar;
• oil particles;
• gas oil particles.

The resulting products are completely suitable for the production of coke, bitumen, and lubricants.

Distillation columns. The process of processing crude oil using this equipment involves heating it in a coil to a temperature of 320 degrees. After this, the mixture enters the intermediate levels of the distillation column. On average, it has 30-60 gutters, each of which is placed at a certain interval and equipped with a bath of liquid. This causes the vapor to flow down in the form of droplets as condensation forms.

There is also processing using heat exchangers.

Recycling

After determining the properties of the oil, depending on the need for a certain end product, the type of secondary distillation is selected. Basically, it consists of a thermal-catalytic effect on the feedstock. Deep oil refining can occur using several methods.

Fuel. The use of this secondary distillation method makes it possible to obtain a number of high-quality products - motor gasoline, diesel, jet, and boiler fuels. To carry out processing, you do not need to use a lot of equipment. As a result of using this method, a finished product is obtained from heavy fractions of raw materials and sediment. The fuel distillation method includes:

• cracking;
• reforming;
• hydrotreating;
• hydrocracking.

Fuel and oil. As a result of using this distillation method, not only various fuels are obtained, but also asphalt and lubricating oils. This is done using the extraction method, deasphalting.

Petrochemical. As a result of applying this method with the use of high-tech equipment, a large number of products are obtained. This is not only fuel, oils, but also plastics, rubber, fertilizers, acetone, alcohol and much more.

How the objects around us are made from oil and gas - accessible and understandable

This method is considered the most common. It is used to process sulfur or high-sulfur oil. Hydrotreating can significantly improve the quality of the resulting fuels. Various additives are removed from them - sulfur, nitrogen, oxygen compounds. The material is processed using special catalysts in a hydrogen environment. In this case, the temperature in the equipment reaches 300-400 degrees, and the pressure – 2-4 MPa.

As a result of distillation, the organic compounds contained in the raw material decompose when interacting with hydrogen circulating inside the apparatus. As a result, ammonia and hydrogen sulfide are formed, which are removed from the catalyst. Hydrotreating allows you to process 95-99% of raw materials.

Catalytic cracking

Distillation is carried out using zeolite-containing catalysts at a temperature of 550 degrees. Cracking is considered a very effective method of processing prepared raw materials. With its help, high-octane motor gasoline can be obtained from fuel oil fractions. The yield of pure product in this case is 40-60%. Liquid gas is also obtained (10-15% of the original volume).

Catalytic reforming

Reforming is carried out using an aluminum-platinum catalyst at a temperature of 500 degrees and a pressure of 1-4 MPa. At the same time, a hydrogen environment is present inside the equipment. This method is used to convert naphthenic and paraffinic hydrocarbons into aromatic ones. This allows you to significantly increase the octane number of manufactured products. When using catalytic reforming, the yield of pure material is 73-90% of the recovered raw material.

Hydrocracking

Allows you to obtain liquid fuel when exposed to high pressure (280 atmospheres) and temperature (450 degrees). This process also occurs with the use of strong catalysts – molybdenum oxides.

If hydrocracking is combined with other methods of processing natural raw materials, the yield of pure products in the form of gasoline and jet fuel is 75-80%. When using high-quality catalysts, their regeneration may not be carried out for 2-3 years.

Extraction and deasphalting

Extraction involves dividing the prepared raw material into the required fractions using solvents. Subsequently, dewaxing is carried out. It allows you to significantly reduce the pour point of the oil. Also, to obtain high quality products, they are hydrotreated. As a result of extraction, diesel fuel can be obtained. Also, using this technique, aromatic hydrocarbons are extracted from prepared raw materials.

Deasphalting is necessary in order to obtain resin-asphaltene compounds from the final products of distillation of petroleum feedstock. The resulting substances are actively used for the production of bitumen, as catalysts for other processing methods.

Other processing methods

Processing of natural raw materials after primary distillation can be carried out in other ways.

Alkylation. After processing the prepared materials, high-quality components for gasoline are obtained. The method is based on the chemical interaction of olefin and paraffin hydrocarbons, resulting in a high-boiling paraffinic hydrocarbon.

Isomerization. The use of this method makes it possible to obtain a substance with a higher octane number from low-octane paraffinic hydrocarbons.

Polymerization. Allows the conversion of butylenes and propylene into oligomeric compounds. As a result, materials are obtained for the production of gasoline and for various petrochemical processes.

Coking. It is used for the production of petroleum coke from heavy fractions obtained after oil distillation.

The oil refining industry is a promising and developing one. The production process is constantly being improved through the introduction of new equipment and techniques.

Video: Oil refining

The development of the Russian oil refining industry in recent years has a clear tendency to improve the state of the industry. With increasing refining volumes, the quality of produced motor fuels is gradually improving. At a number of Russian refineries, new complexes for deep oil refining are being built, some of which have already been put into operation. However, for further progress, much more needs to be done, in particular, to adopt legislation tightening the quality indicators of petroleum products, and to change the state tax policy in the field of oil refining. In addition, to accelerate the transformation of the industry and stimulate conditions for the development and implementation of competitive domestic technologies and equipment, the design market should be reorganized, primarily through the creation of a Russian state scientific and engineering center for oil refining and petrochemicals. Today, an extremely favorable situation is emerging for global oil refining, with prices for light petroleum products growing twice as fast as prices for crude oil. The increase in the profitability of the industry leads to the fact that oil-producing countries began to actively build and introduce new processing capacities in order to export not raw materials, but petroleum products and petrochemicals. This applies to countries such as Iran, Saudi Arabia, Kuwait, UAE, Venezuela, etc. Suffice it to say that in Qatar alone it is planned to introduce processing capacity for 31 million twag. A global trend, most pronounced in industrialized countries importing petroleum products, has been the tightening of environmental legislation aimed at reducing harmful emissions from fuel combustion, as well as the constant increase in requirements for the quality of petroleum products. If we talk about the most important product of the industry - motor fuel, the trends of recent years show that, for example, in the EU countries the demand for distillate diesel fuels and high-quality gasoline is growing most rapidly. Gasoline consumption in the US and Asia-Pacific countries is also increasing. The demand for jet fuel will grow to a lesser extent, and the market demand for boiler fuel will gradually decrease. This global trend must be taken into account when modernizing the Russian oil refining industry. The oil refining industry in Russia lags significantly behind the industrialized countries of the world in its development. The main problems of the industry are the low depth of oil refining, the low quality of produced petroleum products, the backward structure of production, the high degree of wear and tear of fixed assets, and the high level of energy consumption. Russian oil refineries are characterized by a low level of conversion of petroleum feedstock into more valuable refined products. On average in the Russian Federation, the output of main motor fuels (motor gasoline, diesel fuel) is inferior to the indicators of oil refining in the industrialized countries of the world, and the share of fuel oil production is the highest. Due to the low depth of refining, Russian refineries are loaded at 70-75%, while global oil refining today, due to huge demand and high prices for petroleum products, is characterized by a load close to 100%. In 2005, while the four largest Western oil companies processed more oil than they themselves produced, the four Russian companies processed much less oil than their production volumes. That is, if in the West companies strive to earn as much as possible from oil refining and therefore buy additional oil on the side, then Russian companies are forced to mainly focus on the export of crude oil, since the quality of their oil products is such that it is difficult to sell it abroad. A significant share of petroleum products produced at Russian enterprises are made up of outdated fuels, the quality of which does not meet modern world standards. The share of fuel oil in the products of Russian refineries is still large (in 2005, 56.6 million tons were produced, i.e. almost as much as motor gasoline). The quality of motor fuels produced in Russia reflects the technical condition of the country's vehicle fleet. In particular, the presence in the fleet of cars and trucks of outdated models that consume low-grade fuel (A-76 gasoline) necessitates maintaining its production at Russian refineries. The low quality of produced petroleum products is due to the backward structure of oil refining at most Russian refineries, in which not only the share of destructive deepening processes is low, but also secondary processes aimed at improving the quality of produced petroleum products. Exports of Russian oil refining consist mainly of relatively cheap petroleum products, including straight-run gasoline, vacuum gas oil, diesel fuel of low quality in comparison with European requirements in terms of sulfur content, as well as heating oil and base oils. The share of commercial petroleum products with high added value is extremely small. A significant problem in the Russian oil refining industry is the high degree of depreciation of fixed assets, amounting to up to 80%, as well as the use of outdated energy-intensive and economically imperfect technologies. As a result, Russian oil refining is characterized by a high level of energy consumption, which negatively affects the economic efficiency of the industry. The specific consumption of energy resources at operating Russian plants is 2-3 times higher than their foreign counterparts. The capacities of oil refining enterprises are distributed unevenly and irrationally across Russia. Most Russian refineries are located inland, far from sea export transshipment bases, which significantly reduces the efficiency of exporting petroleum products. A consequence of serious problems with the location of the industry is the growth in the number of mini-refineries with a primary processing capacity of 10 to 500 thousand tons. Currently, they produce about 2% of all petroleum products produced in the country. As a rule, such mini-refineries carry out unskilled processing of petroleum raw materials, and their existence significantly complicates the environmental situation in the regions. Recently, there has been a tendency towards improving the state of the Russian oil refining industry. Signs of improvement are a significant increase in investment by Russian oil companies in oil refining, an increase in oil refining volumes, a gradual improvement in the quality of produced motor fuels due to the abandonment of the production of leaded motor gasoline, and an increase in the share of production of high-octane gasoline and environmentally friendly diesel fuels. The total installed capacity of Russian refineries, including mini-refineries, is 275.3 million tons, but only about 75% of the capacity is used - the rest is idle due to moral and physical wear and tear of equipment. Bashkortostan has the largest total oil refining capacity; they are owned by the companies OJSC Bashneftekhim and OJSC Salavatnefteorgsintez. Fig.39. Oil refining (without mini-refineries) in the constituent entities of the Russian Federation in 2007, million tons The largest enterprises in the refining sector are the Omsk Oil Refinery with an installed capacity of primary oil refining of 19.5 million tons per year, the Ryazan Oil Refinery (18.2 million tons), the Kirishinefteorgsintez (17.3 million tons) and the plant of the Angarsk Petrochemical Corporation in Angarsk (16.4 million tons). Among oil companies, it ranks first in terms of installed oil refining capacity at the beginning of 2007. occupied by the company OJSC NK Rosneft - 61.4 million tons per year. It was also the leader in oil refining in 2007. OJSC NK LUKOIL (40.6 million tons) and OJSC Bashneftekhim (32.2 million tons) have smaller capacities. In 2007 domestic refineries received 229.5 million tons, or about 48% of the oil produced; this is almost 8 million tons more than in 2006. Of these, 227.7 million were processed, or about 99.2% of the supplied raw materials. Almost all of it is processed at 27 major refineries. Irreversible oil losses at Russian refineries amounted to less than 1%. Fig. 40. Structure of primary oil refining by Russian companies in 2007, % (without mini-refineries) Depth of oil refining at Russian enterprises in 2007 amounted to only 71.3%, including at refineries - 70.9% (in 2006 - 71.7 and 71.2%, respectively). At foreign factories, the value of this indicator is 85-90% and higher. The greatest refining depth was achieved at the OJSC LUKOIL-Permnefteorgsintez plant (84.1%), at the Omsk Refinery of the Gazprom Neft OJSC (83.3%) and at the Novoufimsky Refinery of the Bashneftekhim OJSC (82.1%). The complexity factor of oil refining is low, as a result of which the country has limited ability to produce high-quality motor fuel, while the share of heating oil in the gross volume of petroleum products produced is still very high - more than 33% (in developed countries it averages 12%, in the USA - about 7 %). However, the share of high-octane gasoline production (A-92 and higher) in the total production of motor gasoline in the Russian Federation is constantly growing; in 2007 it amounted to 74.5%. Fig.41. Production of petroleum products in the Russian Federation in 2007, million tons Fig. 42. Structure of production of main petroleum products in Russia in 2007, % In recent years, a number of Russian refineries have been actively constructing new deep oil refining complexes (DOC). A vacuum gas oil hydrocracking complex was launched at the Perm Oil Refinery (LUKOIL OJSC), a gas-gas oil hydrotreating complex was launched at the Slavneft Yaroslavl Oil Refinery, and a vacuum gas oil hydrotreating complex was launched at the Ryazan Oil Refinery, owned by TNK-BP. The catalytic cracking complex was launched at the Nizhnekamsk Refinery of the TAIF company. The commissioning of the above-mentioned gas refining stations made it possible to significantly increase the depth of oil refining and thereby reduce the amount of fuel oil produced by the refinery and significantly increase the volume of light petroleum products produced. At the same time, the reconstructed refineries began to produce petroleum products of European quality, and the environmental situation in the areas where the enterprises were located was improved. Due to the commissioning of new gas pumping stations, the production volumes of motor fuels increased by more than 1.6 million tg for gasoline, and for diesel fuel by more than 2.5 million tg. Unfortunately, in the process of modernizing Russian oil refining, domestic developments are practically not used. Most of the technologies and equipment necessary for the commissioning of new gas-gas pumping stations at domestic refineries are purchased from leading Western manufacturers. Perhaps the only exception to the general rule was the project for the construction of a catalytic cracking complex in Nizhnekamsk, developed by the Russian VNIINP and VNIPIneft. It is known that the oil produced in Tatarstan is heavy, high-sulfur, and adding it to the Urals export mixture has a negative impact on the price of Russian oil on the world market. In order to reduce the export of oil with high sulfur content, Tatarstan is forced to build new facilities on its territory to process its raw materials locally. The planned construction by Tatneft of a new processing complex in Nizhnekamsk, in addition to the goal of reducing oil sales abroad, also aims to obtain additional volumes of motor fuel of European quality, which could be exported in the future instead of oil. Fig. 43. Dynamics of production of high- and low-octane gasoline in the Russian Federation in 2000-2007, million tons. In the near future, Russia is expected to join the World Trade Organization (WTO), which should have a significant impact on domestic oil refining. Positive impacts include the need to tighten environmental laws and increase requirements for the quality of petroleum products. The introduction of European standards (Euro-4, Euro-5) will create the prerequisites for the production of high-quality motor fuels and oils in Russia. Another positive development could be improved conditions for access to foreign markets. At the same time, in order to stimulate domestic oil refining to produce high-quality petroleum products, it is necessary to establish preferential excise tax rates on petroleum products of Euro-4 and Euro-5 standards. Another advantage is the need to amend Russian legislation in the field of certification. The disadvantages of Russia's accession to the WTO include the opening of the domestic market for goods and services, which will lead to a significant increase in competition from foreign oil and engineering companies and equipment manufacturers. It should be noted that already today 50-70% of the catalysts used in oil refining and more than 200 types of fuel and oil additives necessary for military and civilian equipment are supplied by foreign companies. The world's leading licensors and engineering companies with significant financial potential have actively entered the Russian market. This led to the cessation of the introduction of new domestic oil refining technological processes in Russia, the displacement of Russian design organizations from the domestic market of engineering services, and a sharp increase in the number of imported equipment during the modernization of oil refineries. To counter the complete takeover of the Russian market by Western firms, first of all, it is necessary to strengthen government regulation in order to protect the domestic market with import and countervailing tariffs. An important measure could be the process of consolidation of Russian design organizations. Today, in the Russian oil refining market, along with traditional design organizations with significant experience and technical capabilities, there are small companies that are not capable of producing high-quality design documentation. As a result, the quality of industrial installations decreases, economic indicators and the level of safety of production deteriorate. To improve the situation on the engineering market, it is advisable to tighten the requirements for licensing engineering activities in Russia. Thus, an analysis of trends in the development of domestic oil refining in recent years allows us to conclude that there are positive changes in the industry. The process of active modernization of refinery fixed assets and the construction of new deep oil refining complexes at a number of plants has begun. However, in general, a number of problems remain in the industry, the solution of which, in our opinion, could be facilitated by the following measures: - adoption of legislation tightening the requirements for the quality of produced petroleum products; - introduction of tax incentive measures for industry modernization; - strengthening the positions of leading domestic design organizations through the reorganization of the design market; - creation of a large domestic engineering company for oil refining and petrochemicals; - creating conditions for the development and implementation of competitive domestic technologies, equipment, catalysts and additives.
The essence of oil refining production
The oil refining process can be divided into 3 main stages:
1. Separation of petroleum feedstock into fractions that differ in boiling temperature ranges (primary processing);
2. Processing of the obtained fractions by chemical transformations of the hydrocarbons they contain and the production of components of commercial petroleum products (recycling);
3. Mixing components with the involvement, if necessary, of various additives, to obtain commercial petroleum products with specified quality indicators (commodity production).
The refinery's products include motor and boiler fuels, liquefied gases, various types of raw materials for petrochemical production, and also, depending on the technological scheme of the enterprise, lubricating, hydraulic and other oils, bitumen, petroleum cokes, paraffins. Based on the set of technological processes, the refinery can produce from 5 to more than 40 items of commercial petroleum products.
Oil refining is a continuous production; the period of production between major overhauls at modern plants is up to 3 years. The functional unit of a refinery is the technological installation- a production facility with a set of equipment that allows the full cycle of a particular technological process to be carried out.
This material briefly describes the main technological processes of fuel production - the production of motor and boiler fuels, as well as coke.

Delivery and reception of oil
In Russia, the main volumes of crude oil supplied for processing are supplied to refineries from production associations via main oil pipelines. Small quantities of oil, as well as gas condensate, are supplied by rail. In oil importing countries with access to the sea, supplies to port refineries are carried out by water transport.
Raw materials received at the plant are supplied to the appropriate containers commodity base(Fig. 1), connected by pipelines to all process units of the refinery. The amount of oil received is determined according to instrument metering data, or by measurements in raw material tanks.

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

Primary oil refining
Desalted oil from the ELOU is supplied to an atmospheric-vacuum distillation unit, which at Russian refineries is designated by the abbreviation AVT - atmospheric-vacuum tube. This name is due to the fact that the heating of the raw material before dividing 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.
AVT 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% of oil. The remainder of atmospheric distillation is fuel oil.
The process consists of separating oil heated in a furnace into separate fractions into distillation column- a cylindrical vertical apparatus, inside of which there are contact devices (plates), through which vapor moves upward and liquid moves downward. Distillation columns of various sizes and configurations are used in almost all oil refining installations; the number of trays in them varies from 20 to 60. Heat is supplied to the bottom of the column and heat is removed from the top 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 vapor, and the vapors of the kerosene and diesel fractions are condensed in the corresponding parts of the column and 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 fuel-oil profile, or wide oil fraction (vacuum gas oil) at a fuel profile refinery. The remainder of vacuum distillation is tar.
The need to select oil fractions under vacuum is due to the fact that at temperatures above 380°C the thermal decomposition of hydrocarbons begins (cracking), and the boiling point of vacuum gas oil is 520°C or more. Therefore, 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 in an atmospheric unit contains gases (mainly propane and butane) in a volume exceeding quality requirements and cannot be used either as a component of motor gasoline or as commercial straight-run gasoline. In addition, oil refining processes aimed at increasing the octane number of gasoline and the production of aromatic hydrocarbons use narrow gasoline fractions as raw materials. This explains the inclusion of this process in the technological scheme of oil refining (Fig. 4), in which liquefied gases are distilled from the gasoline fraction, and it is distilled into 2-5 narrow fractions on the appropriate number of columns.

Primary oil refining products are cooled in heat exchangers, in which heat is transferred to cold raw materials supplied for processing, due to which process fuel is saved, in water and air refrigerators and are taken out of production. A similar heat exchange scheme is used in other refinery units.

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

Primary petroleum products

Name	Boiling ranges (compound)	Where is it selected?	Where is it used? (in order of priority)
Reflux stabilization	Propane, butane, isobutane	Stabilization block	Gas fractionation, commercial products, process fuel
Stable straight-run gasoline (naphtha)		Secondary distillation of gasoline	Gasoline blending, commercial products
Stable light petrol		Stabilization block	Isomerization, gasoline blending, commercial products
Benzene		Secondary distillation of gasoline	Production of corresponding aromatic hydrocarbons
Toluene		Secondary distillation of gasoline
Xylene		Secondary distillation of gasoline
Catalytic reforming feedstock		Secondary distillation of gasoline	Catalytic reforming
Heavy petrol		Secondary distillation of gasoline	Mixing kerosene, winter diesel fuel, catalytic reforming
Kerosene component		Atmospheric distillation	Mixing kerosene and diesel fuels
Diesel		Atmospheric distillation	Hydrotreating, mixing of diesel fuels, fuel oils
		Atmospheric distillation (residue)	Vacuum distillation, hydrocracking, fuel oil mixing
Vacuum gas oil		Vacuum distillation	Catalytic cracking, hydrocracking, commercial products, fuel oil mixing.
		Vacuum distillation (residue)	Coking, hydrocracking, fuel oil mixing.

*) - n.k. - beginning of boiling
**) - k.k. - end of boiling

Photos 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 Oil Refinery designed by 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 tubular stove (yellow).	Fig.7. Vacuum-creating equipment from Graham. Three ejectors are visible, into which vapors enter from the top of the column.

Sergei Pronin