RU2363721C1 - Method for preparation of liquid hydrocarbon raw materials - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention is related to method for preparation of liquid hydrocarbon raw materials, including supply of raw materials and heat carrier, their heating, separation of raw materials into two parts - light steam and gas part of separation (low boiling fractions LBF) and heavy part of separation (high boiling fractions HBF), withdrawal of separation products, raw materials and heat carrier are heated separately prior to mixing stage, then processed raw materials are sent to stage of evaporation and separation into LBF (low boiling fraction) and HBF (high boiling fraction), LBF in the form of steam and gas flow is sent to separation stage, after which steam and gas phase of LBF is sent for processing to prepare light oil products, liquid fraction (filtrate) separated at stage of LBF separation is returned to repeated treatment to the stage of raw materials mixing and heating with heat carrier for additional preparation of light products, heavy part of separation (high boiling fractions HBF) in the form of liquid flow is sent to stage of heat carrier separation, heat carrier is sent to stage of heat carrier heating and further to stage of raw materials mixing and heating, liquid phase of HBF separated from heat carrier is sent to processing and preparation of heavy end products, heat exchange devices, in which heat carrier directly contacts with raw materials, and devices for heating of heat carrier create closed circuit for circulation of heat carrier, besides, stages of raw materials mixing and heating with heat carrier, processing with mechanical and wave action, evaporation and separation into steam and gas and liquid phases, and also separation of LBF are combined in single device, where simultaneously process of thermomechanical cracking is executed.

EFFECT: preparation of liquid hydrocarbon raw materials.

6 cl, 5 ex, 3 tbl, 1 dwg

Description

The invention relates to the field of preparation of oil (including heavy), fuel oil, sludge, waste oils and other liquid hydrocarbon media for further in-depth processing and can be used in the production of hydrocarbon fuels, petrochemicals, oils, bitumen, etc.

Technological schemes for oil refining have several options. There is a full technological cycle, which includes the following main industries: production of fuels, production of petrochemical products, production of lubricants and special oils, production of additives. Specialized variants of technological schemes are possible: only fuel or only fuel-oil (Dekhterman A.Sh. Oil refining according to the fuel option. M., "Chemistry", 1988, p.13). In all cases, devices for preliminary evaporation of oil are used at the beginning of the technological process. The preliminary evaporation of gas and the bulk of gasoline allows you to reduce the pressure at the inlet of the feed pump, relieve the furnace from heating light fractions, reduce the vapor velocity and reduce the diameter of the main distillation column. At large oil refineries (refineries), distillation column apparatuses are used for this purpose.

The primary distillation of oil at the refinery is carried out in two ways: by single evaporation in one distillation column and with preliminary evaporation of light fractions or double evaporation (Bagirov I.T. High-performance atmospheric and atmospheric vacuum installations. M., Chemistry, 1964, p.5 ; Dekhterman A.Sh. Oil refining according to the fuel version. M., "Chemistry", 1988, p.41). The latter method is used most often, since it allows to increase the depth of distillate selection within the limits of their potential content in raw materials. We briefly consider the sequence of operations of primary distillation carried out according to the classical scheme.

Before the oil is fed to the separation, its preparation is required. Oil preparation is carried out in blocks ELOU (electro-dehydrating and desalting plant). Equipment difficult to manufacture and operate, explosive (Dekhterman A.Sh. Oil refining according to the fuel version. M., "Chemistry", 1988, p. 36).

To separate the hydrocarbon feed (including oil) it is heated. At the enterprises of the oil refining and petrochemical industries, this operation is performed by supplying heat through a dividing wall (coil) by burning fuel. For this purpose, various tube furnaces are used (Entus N.R., Sharikhin V.V. Tube furnaces in the oil refining and petrochemical industries. M., "Chemistry", 1987, p.6 and others). Liquid and gaseous hydrocarbons are heated in them. In this case, the following processes can occur: heating, evaporation, overheating. Heated hydrocarbon feed passes through the coils. Heat transfer to the raw material occurs, as noted, through its wall. There is a limitation on the thermal stress of the heating surface. Deposits of salts or coke on the coil walls cause a rapid increase in the temperature of the pipe walls, which ultimately leads to a sharp reduction in the service life of the chimneys. Therefore, for raw materials containing resinous compounds, the heat stress is set low. The decrease in oil reserves of traditional fields increases interest in the extraction and, accordingly, processing of heavy oils (Ratov AN, Nemirovskaya GB and other problems of oil development in the Ulyanovsk region. "Chemistry and technology of fuels and oils", No. 4, 1995 ) Therefore, the use of tubular heaters for such oils becomes problematic. In addition, coils require the use of high alloy, expensive steel. In general, a tube furnace is a complex and expensive equipment that has a limited resource.

The separation of oil into fractions is based on the difference in the boiling point of its components. The low-boiling part passes into the vapor phase and, after condensation, forms a distillate. For a clear separation of the mixture, atmospheric or vacuum distillation is used (A. Dekhterman, Oil refining according to the fuel version. M., Chemistry, 1988, p. 26). Rectification apparatus refers to a fairly technologically advanced and structurally-used equipment. However, it is sophisticated equipment. Column distillation apparatuses used at large refineries are quite expensive to manufacture and operate. Therefore, at the stage of preliminary oil separation, it is advisable to use simpler devices, such as evaporators (A. Dekhterman, Oil refining according to the fuel version. M., "Chemistry", 1988, p.23). The evaporator is a cylindrical tank. At the bottom of its housing is an integrated tubular heat exchanger. A coolant is supplied inside the tubes of the heat exchanger to heat the product (oil). Typically, water vapor is used as a heat transfer medium. The light part of the oil (gasoline fraction) evaporates and is discharged through the upper fitting. The remaining oil is poured through the drain plate and is discharged through the corresponding fitting. The amount of evaporated part of the oil depends on the temperature in the apparatus, that is, on the surface of the heat exchanger and the temperature of the coolant. The surface of the heat exchanger during operation is covered by deposits of oil, and heat transfer conditions are significantly worsened. This process is significantly accelerated with increasing temperature of the coolant. Therefore, devices of this type have limitations in terms of intensifying the process of separation and evaporation of part of the liquid hydrocarbon feedstock. The temperature of the process is 200-230 ° C. This temperature corresponds to a certain evaporated part of the oil (feedstock).

The considered operations (preparation, heating, proper separation of the low boiling fraction) in the process of hydrocarbon separation occur sequentially, that is, are not combined in time. Each of them requires a separate sophisticated equipment. Some types of equipment have a limited resource.

The closest analogue (prototype) is the process of heating the raw material and its separation into fractions, described above.

The technical result to which the claimed invention is directed is to increase the intensification of the process of evaporation and separation of oil fractions (raw materials) while maintaining the simplicity of the design of the separation unit in manufacture and operation.

As a result, after the separation stage, two main products are obtained: the light part of the gas-vapor separation (low boiling fractions of NKF), with a boiling point predominantly up to 350-360 ° С, which can be called very light oil or gas condensate, and the heavy part or residue separation in liquid form (high boiling fraction separation VKF). NKF consists mainly (80-90 wt.% Due to non-ideal separation) of fractions with a boiling point up to 350-360 ° C. During further processing by known methods, fuel products such as gasoline (boiling range: boiling point 180-200 ° С), kerosene (boiling range: 180-200 ° С - 230-240 ° С), diesel fuel (such as boiling temperature range: 230-240 ° С - 350-360 ° С), petrochemical products, such as toluene, benzene, etc. In the future - light commercial products. VKF consists of heavy fractions with a boiling point primarily above 350-360 ° C. During further processing by known methods, VKF can produce heavy commercial products, such as coke, bitumen, bitumen emulsions, coatings, etc. In the future, heavy commercial products. The boundary separation temperature of 350-360 ° C is selected because the end of the boiling of diesel fuel is 350-360 ° C. If the guests and requirements for fuel products change over time, the separation boundary temperature can be changed accordingly. The stages for obtaining marketable products usually include the following well-known processes: hydrotreating, reforming, platforming, etc. (for producing gasoline, kerosene, diesel fuel), processes of the petrochemical and chemical industries, or at the first stage of the compounding stage, bitumen block for the production of oxidized bitumen or a bitumen block combined with a vacuum block for the production of non-oxidized bitumen, as well as equipment for the production of bitumen coatings, emulsions, boiler fuel, coke and other commodity products Uktov (Petrochemistry Handbook. In two volumes. Volume 1, under the editorship of Ogorodnikov S.K. L., "Chemistry", 1978, p. 53-55).

By intensification is meant an increase in the apparatus’s productivity in oil. In addition, depending on the further technological scheme of processing raw materials into fuel, it may be necessary to increase the quantitatively evaporated part of the oil, that is, to increase the temperature of the process. An increase in the temperature of the process is also possible using the proposed method. In addition, an increase in temperature will allow thermal or thermomechanical cracking of raw materials to increase the depth of processing.

The aim of the invention is to increase the yield of light light fractions (gasoline, kerosene and diesel, petrochemical products, etc.) higher than their potential content in raw materials and increase the depth of processing, reduce operating and capital costs, reduce coking and increase the overhaul mileage of equipment with a continuous process, and also the optimal and rational use of raw materials in their further processing.

The technical result is achieved by the fact that in the proposed method, heat exchangers in the stage of heating the raw material with a coolant are designed in such a way that the heat transfer of the raw materials from the coolant is carried out not through the dividing wall, but with direct contact of the coolant and raw materials, and the ratio of the flow of coolant and raw materials is in the range 1 ÷ 100. This allows you to increase the efficiency of heat transfer and, accordingly, the evaporation rate of low-boiling oil fractions. That is, to increase the productivity of the process and equipment. In addition, direct contact of the media leads to intense heat transfer. The result is a significant increase in the rate of evaporation and the transition to the vapor phase of hydrocarbons with a boiling point higher than the average temperature of the total flow of both media. Direct contact of the heat carrier and oil eliminates the formation of deposits on the surface of the heat exchanger at an elevated temperature of the process. This leads to a decrease in coking equipment, an increase in the overhaul mileage of equipment and the continuity of the process. Accordingly, the temperature of the separation and evaporation process can be increased, if necessary, from 200-230 ° C to 350-450 ° C or more, especially when using high-temperature coolants. In addition, this allows the operation of thermal and / or thermomechanical cracking to be applied to raw materials, coolant, as well as to their mixture of mechanical and wave effects of various types and a wide range of frequencies (for example, using cavitation, sound and ultrasonic processing of raw materials on special devices , for example, hydrodynamic, rotor-pulsation or other type) simultaneously with the evaporation (separation) of oil or other liquid hydrocarbon feedstocks. Moreover, the raw materials are heated with a coolant to a temperature lower than the temperature of the onset of avalanche-like thermal cracking by several degrees or tens of degrees Celsius, which can significantly reduce coking and increase the overhaul mileage of the equipment with a continuous process. This, in turn, makes it possible to increase the depth of processing of raw materials and the yield of light light fractions above their potential content in raw materials. When using a high-temperature coolant, it becomes expedient to organize its circulation circuit, i.e. separation unit. The coolant circulates in a closed circuit: separation apparatus (evaporation) - heating medium heating furnace - separation apparatus (evaporation). That is, the heat carrier is removed from the apparatus through the corresponding fittings, heated in the furnace to the required temperature, and again fed into the heat exchange devices through the inlet fitting. As a heat carrier it is possible to use media that are not miscible with oil, for example liquid metals (for example, liquid sodium), molten salts, high-temperature organic and gas coolants, for example water vapor, nitrogen, helium (Petukhov BC, Genin L.G., S. A. Kovalev, Heat Transfer in Nuclear Power Plants (Moscow, Energoatomizdat, 1986, pp. 22-23).

The use of water vapor as a heat carrier, for example, as in the method of thermal cracking of tar with superheated water vapor (Kon M.Ya., Shershun V.G. Oil refining and petrochemical industry abroad. Handbook. M., "Chemistry", 1986, p. 124), has a lot of disadvantages and is not widely used in industry. To obtain good results on the separation of liquid hydrocarbon feedstocks, the mass ratio of steam and feedstock should be no lower than 5: 1 or more. At industrial costs of the hydrocarbon mixture, a large steam boiler and a steam superheater up to 600-650 ° C and more are required, and provided that the water has an abnormally high heat of vaporization, this leads to unreasonably large costs and energy losses. After separation, the NKF hydrocarbon-gas phase contains a huge amount of water vapor, several times higher than the amount of hydrocarbon vapor phase. The vapor-gas phase of separation with a huge amount of water vapor cannot immediately be directed to a distillation column. It is necessary to condense the entire stream, while due to the large availability of water, the requirements for heat exchange equipment increase sharply, and heat losses naturally increase. Then the cooled vapor-gas phase has to be separated from the water. This causes a large amount of wastewater contaminated with organic matter.

The use of nitrogen, methane and other gases as a gaseous heat carrier (in particular, organic gases obtained, for example, directly during the implementation of this method) with temperatures up to 650 ° C and higher and high pressure has its serious drawbacks, although the use of such heat carriers is much more profitable than the use of water-based steam coolant and gives good results, especially if a gas fraction is used as the coolant, obtained directly by separation of raw materials according to mu method. When using gas coolants, high-temperature and high-pressure compressors are necessary, and this is very energy-intensive, expensive and short-lived equipment. In addition, the mass ratio of gas and oil (raw materials) to obtain a good separation result should be 5: 1 or more. With this ratio, the requirements for heat exchange equipment for condensation of the vapor-gas phase of the separation of a mixture of hydrocarbons increase, its dimensions and cost increase.

When working with liquid metals and molten salts, there are some disadvantages, for example, associated with the use of pumping equipment, problems of starting work, etc., although the use of such coolants allows you to get good results.

Therefore, the most convenient and practical heat transfer media are high-temperature organic and organosilicon liquids with a high boiling point - the remains of oil refineries, terphenyl and fluorocarbon mixtures, perfluorobenzene, etc. (Yu.M. Babikov, D. S. Rasskazov. Organic and organosilicon heat carriers. M., "Energy", 1975, S. 62-72).

It should be borne in mind that it is necessary to heat the coolant before mixing it with the raw material (in contrast to the method according to the copyright certificate SU 1558879, in which the mixture of raw materials and coolant is heated, which leads to an increase in pressure in the coil due to the presence of light fractions in the raw material, plugs, coking, etc., while the heating temperature cannot be raised above 380 ° C, which ultimately leads to only 69-78% of light petroleum products from their potential content in the feedstock, and talk here about the increase depths ne processing, i.e. obtaining light light products above their potential content in raw materials, is not necessary)

In order to avoid the above drawbacks when conducting bench research on the implementation of the proposed method, it is proposed, as one of the simplest and most optimal options, to use the heavy residue of the separation of liquid hydrocarbon feedstocks (liquid phase separation VKF) as the coolant, obtained directly during the implementation of the proposed method, the necessary part which returns to the beginning of the process. The use of a heavy separation residue as a coolant (it does not need to be specially prepared or purchased, it appears during the process), which is a high-temperature coolant (the boiling point is mainly above 360 ° C), allows to increase the operating temperature in the separation apparatus, to intensify the thermal or thermomechanical cracking and, accordingly, increase the processing depth and yield of light products above their potential content in the feedstock, and also simplify l and reduce the cost of equipment and reduce energy and operating costs, and also allows you to optimally and efficiently use raw materials, since in-depth processing to obtain a certain amount of marketable products requires less oil or other liquid hydrocarbon feedstocks.

The vapor-gas part of the separation of NKF, due to the intensively conducted process of evaporation and separation, contains, in addition to light fractions in a gaseous form, and liquid droplets, in which there are heavy high-boiling components with a boiling point above 360 ° C. Therefore, NKF is first sent to the separation stage - filtration, droplet separation, distillation, after the separation stage, the NKF gas-vapor phase is sent to the stage of obtaining light commercial products (hydrotreatment, rifming, etc.), since it contains mainly gasoline, kerosene and diesel fractions, as well as petrochemicals. Commercial products can be obtained at the place of implementation of the proposed method or, after cooling (for simplicity, not shown in the diagram), the combined cycle gas phase of the NFC is transported to the place of final processing and receipt of commercial products. The filtrate after the separation stage is returned to the beginning of the process for reprocessing to the stage of mixing and heating the raw material with a coolant and obtaining an additional amount of NKF and, ultimately, an additional amount of light target products. The liquid part of the separation (VKF), which, due to non-ideal separation, may contain some small amount (depending on the properties of the raw material) of light fractions with a boiling point below 360 ° C, is sent (after the separation from the coolant, which is returned, after appropriate heating, to the beginning of the process) to the stage of separation of light fractions (distillation) from it, for example, to a vacuum column. Lungs + distillation after the vacuum device is returned, if necessary (depending on the properties of the raw materials and the task), at the beginning of the process for reprocessing and obtaining an additional amount of NKF and, accordingly, light target products. In some cases, if the raw material contains many resins, asphaltenes, etc., VKF will already be a good raw material for the production of, for example, bitumen, then the stage of obtaining a light distillation from VKF is not needed. After the light distillation separation step, the remaining liquid phase of the VKF is fed, for example, to a bitumen reactor to produce marketable bitumen, or to a plant for producing bitumen coatings, emulsions, coke, etc., i.e. to obtain heavy commercial products in place, or, after cooling (for simplicity, not shown in the diagram), transported for final processing to another place. Direct contact of a heat carrier heated to a high temperature (for example, up to 400 ° C and higher, depending on the process conditions) and colder oil or other liquid hydrocarbon feed (for example, at a temperature of 200 ° C) leads to an explosive nature of the heating of the raw material , the occurrence of oscillations and local cavitation zones, which in turn initiates thermomechanical cracking of heavy oil molecules and leads to an increase in the yield of light fractions (gasoline, kerosene, diesel, petrochemical products, etc.) by 1.5-15 times depending on the composition of the raw materials (heavy oil, fuel oil, etc.). The heat carrier in the preparation process at the stage of its heating must be heated not lower than 300 ° C, and the preliminary heating of the raw material before the stage of mixing it with the heat carrier must be no higher than 400 ° C in order to avoid coking.

For cavitation treatment of oil (raw materials), coolant and their mixture and application of mechanical and wave action, special devices are also used, the action of which is based, as the most optimal option, on the hydrodynamic effects of medium movement with a high (over 5 m / s) velocity along the channels with obstacles and turns of various shapes, which leads to the appearance of local zones of reduced pressure, in which the evaporation process is more intense, and at sufficiently high temperatures also occurs thermomechanically cracking feedstock to obtain additional amounts of light fractions. With this approach, the cavitation and acoustic treatment process occurs in the entire volume of the treatment zone, and not only in the near-surface zones, as when using, for example, rotary-pulsation apparatuses (RPA).

Distinctive features of this solution allow several processes to be carried out: heat transfer, local decrease in absolute pressure, evaporation, cavitation and acoustic treatment, initiated thermal and thermomechanical cracking, separation intensively and simultaneously in a single volume with direct contact of the raw material with the coolant. In addition, the end of the evaporation and phase separation process is carried out, creating a significant interfacial surface.

The drawing shows the sequence of stages of the proposed method. The drawing indicates: 1 - the stage of mixing and heating the raw material with a coolant, 2 - the stage of mechanical and wave processing of the mixture of raw materials and coolant, 3 - the stage of separation into NKF and VKF, 4 - the stage of separation of the coolant from VKF, 5 - the stage of heating of the coolant, 6 - stage of separation (droplet separation, filtration or rectification) NKF, 7 - stage selection from VKF light fractions (distillation), for example, using vacuum devices.

The proposed method is implemented in a pilot plant for the separation of oil and other liquid hydrocarbon feeds with a capacity of up to 0.2 t / h, in which all stages for the implementation of the method are implemented. In addition, the installation is equipped with various capacitive equipment for storing raw materials and collecting the resulting products, heat exchange equipment for heating raw materials, coolant and cooling products, pumping equipment and instrumentation. The raw materials used were oil from the Vishenskoye deposit in the Ulyanovsk region (Ratov AN, Nemirovskaya GB and other problems of oil development in the Ulyanovsk region. "Chemistry and technology of fuels and oils", No. 4,

1995). Oil contains many tarry compounds and impurities. Oil of other fields was also used, for example, Nurlatneft oil and gas production unit with a different composition, as well as various still bottoms, used oils, etc. A part of the liquid separation phase (heavy residue — VKF), which is a good high-temperature coolant, was used as a heat carrier. The pressure of raw materials and coolant in bench experiments was up to 1.0 MPa, the temperature of coolant was up to 400 ° C, the temperature of raw materials was up to 200 ° C, the ratio of flow rates of coolant and raw materials was in the range of 2 ÷ 3, the temperature at the separation stage corresponds to a predetermined boundary between NKF and VKF - approximately 360 ° C. At these values of pressure and temperature, the linear feed rates of the raw material and coolant were more than 5 m / s. With an increase in the feed rate of the raw material and coolant, the efficiency of the separation and processing process increases nonlinearly. The choice of the value of the feed rates for a particular technological process depends on the properties of the raw materials, the task at hand and is optimized for several factors, including the economic factor.

Before starting the process of separation of liquid hydrocarbon raw materials, a coolant is prepared. The heat transfer medium, which is essentially a heavy separation residue, can be prepared in various ways, for example, using a simple process of single evaporation of a hydrocarbon mixture. The simplest method, which was used when working on a bench installation, is as follows. The required amount of liquid hydrocarbon feed is poured into the separation apparatus. From the separation apparatus, the mixture is fed to the heater (furnace) and returned back. In this case, light fractions are continuously removed, accumulating a heavy separation residue. With continuous circulation and a certain temperature, a heavy residue after a certain time (process parameters depend on the composition of the initial hydrocarbon mixture) acquires all the properties of a high-temperature coolant. Control of the end of the preparation of the coolant is carried out by determining the physico-chemical properties and composition of the heavy separation residue.

Preheated raw materials and heat carrier heated to the required temperature are pumped to the mixing stage, in which the thermomechanical cracking process is also carried out (see drawing, stage 1). The mixture of raw materials and coolant is fed to the stage of mechanical and wave processing (see drawing, stage 2), in which thermomechanical hydrodynamic cracking of raw materials is also carried out, then to the separation stage into NKF and VKF (see drawing, stage 3). After separation from the VKF (see drawing, stage 4), the coolant is directed to the heating stage (see drawing, stage 5), then to the stage of mixing with raw materials (see drawing, stage 1), i.e. stages of mixing, processing, separation and heating form a closed loop for the circulation of the coolant. The gas-vapor part (NFC) after the separation stage (see drawing, stage 3) is sent to the separation stage (droplet separation, filtration or rectification) (see drawing, stage 6), after which the filtrate or liquid part returns to the beginning of the process to the mixing stage (see drawing, stage 1) for reprocessing and additional obtaining of light products above their potential content due to the thermomechanical cracking process. The vapor-gas phase of the NKF after the separation stage (see drawing, stage 6) is sent to the cooling stage (not shown in the diagram for simplicity) and analyzed. In the industrial version, the combined cycle gas phase of the NKF can be transported for further in-depth processing or processed on site to produce light commercial products - gasoline, kerosene, diesel fuel, petrochemical products, etc. The liquid separation part (VKF) after the separation stage (see drawing, stage 3 ) to the NKF and VKF and separation from the coolant (see drawing, stage 4) is sent to the stage of selection of the light part (distillation) from VKF (see drawing, stage 7) on a vacuum column, light distillation returns to the beginning of the process to the mixing stage I and heating the raw material with a coolant (see drawing, stage 1) for re-processing and additional obtaining of light products above their potential content due to the thermomechanical cracking process. The remainder after the stage of selection of the light part (distillation) from VKF (see drawing, stage 7) is analyzed. In the industrial version, the liquid phase of the VKF is sent to cooling (for simplicity, not shown in the diagram) for transportation for further processing or processed on site to produce heavy commercial products - bitumen, bitumen coatings, emulsions, coke, etc. At the same time, the separation (droplet separation) stage filtration and rectification) NKF and the selection of the light part (distillation) from VKF can be carried out either individually, i.e. only one of them, or both depending on the properties of the feedstock and the task. The stages of processing raw materials, coolant before the mixing stage (not shown in the figure for simplicity), as well as processing the mixture of raw materials and coolant after the mixing stage (see drawing, stage 2) can be carried out separately (raw materials, coolant, mixture of raw materials and coolant) both simultaneously and in pairs. Moreover, the stages of mixing and heating of raw materials with a coolant, processing by mechanical and wave action, the stage of evaporation and separation into gas-vapor and liquid phases, the separation phase of NKF are combined in one apparatus. This reduces the amount of equipment and, accordingly, capital and operating costs. The simplified design of the apparatus, in which the above stages are combined and which is used for bench experiments, is as follows. The 200-liter capacitive apparatus has an inlet side pipe into which raw materials and heated coolant enter and mix. As a result of mixing, the raw material is heated (and when a certain temperature is reached, thermal cracking can occur), then the mixture is subjected to cavitation (mechanical) and acoustic treatment in a device also located in the inlet pipe, and thermomechanical cracking of the raw material occurs. As a specific device during research, a device similar to the device according to the patent SU 546389 was used. Then, the mixture was dispersed into an apparatus to increase the interfacial surface and more efficiently separate the gas-vapor part from the liquid. The combined-cycle part of the NKF is then sent to the outlet pipe located at the top of the apparatus. In the same branch pipe there is a basket with Rashig rings, on which drop separation and separation of the vapor-gas part of the NKF separation take place. At the bottom of the apparatus there is a pipe for the exit of the liquid part of the separation of VKF. The device is very simple, therefore not shown in a separate drawing.

The following are some of the results of the separation process.

Example 1

Oil fields of the Ulyanovsk region.

Separation effect: NKF 76 wt.%, VKF 22 wt.%, Gas yield 2 wt.%. The enlarged fractional composition of oil and NKF after processing by the proposed method (in terms of oil, taking into account the separation coefficient) and some characteristics are shown in table 1.

Table 1 Selection limits The yield of fractions for oil, wt.% Source oil The easy part of the separation (NKF) The beginning of the boil, ° C 68 46 up to 200 ° C 10.6 31,4 up to 250 ° C 15.1 42.9 up to 300 ° C 22.2 56.2 up to 350 ° C 29.9 67.2 Density, kg / m3 941.2 795.7 Kinematic viscosity, cSt, at 20 ° С 87.9 1.3 Sulfur content, wt.% up to 5.0 up to 1.5 Chloride Content, mg / L up to 2000 up to 50

Example 2

Oil NGDU Nurlatneft.

The separation effect: NKF 74 wt.%, VKF 24 wt.%, Loss of 2 wt.%. The enlarged fractional composition of oil and NKF after processing by the proposed method (in terms of oil, taking into account the separation coefficient) and some characteristics are shown in table 2.

table 2 Selection limits The yield of fractions for oil, wt.% Source oil The easy part of the separation (NKF) The beginning of the boil, ° C 38 36 up to 180 ° C 11.9 33.9 up to 240 ° C 19.9 48.6 up to 350 ° C 36.7 65.5 up to 360 ° С 37.8 66.5 Density, kg / cubic m 910.5 791.8 Kinematic viscosity, cSt, at 20 ° С 140.1 1.79 Sulfur content, wt.% 3.64 1.45 Chloride Content, mg / L up to 2000 up to 50

In tables 1 and 2, the amount of obtained NKF was 74-76 wt.%, And the total number of fractions up to 350-360 ° C is 66.5-67.2 wt.%. This is due to the fact that the separation process into NKF and VKF is not ideal (even on a distillation column), therefore, a small part of heavy fractions with a boiling point above 350-360 ° C also get into the NKF.

Example 3

Characteristics of the results of the analysis of the VKF oil separation NGDU Nurlatneft are shown in table 3.

Table 3 Name of indicator Value Test method Penetration depth 0.1 mm at 25 ° C 76 GOST 11501 at 0 ° С 10 The softening temperature of the ring and ball, ° C 47.6 GOST 11506 Stretch, cm
at 25 ° C > 100 GOST 11505 at 0 ° С 2 Fragility temperature, ° С minus 7.7 GOST 11507 with the addition of clause 3.2 Flash point, ° С > 250 GOST 4333 Change in softening temperature after heating, ° C 0.1 GOST 18180, GOST 11506 with the addition of clause 3.3 Penetration index minus 0.7 Appendix 2 Mass fraction of water-soluble compounds,% 0.445 GOST 11510 Adhesion to stone material (control sample), points 3 GOST 11508

Example 4

Atmospheric-vacuum distillation of the bottoms of Ulyanovsk oil after AT (fuel oil) showed the absence of a gasoline fraction in it, the content of the kerosene fraction (240-360 ° C) was 2.9 wt.%, The diesel fraction (240-360 ° C) 11.8 wt.%. The treatment of the investigated bottoms by the proposed method showed the following results: the number of low-boiling fractions (NKF - the easy part of the separation) was 70-75 wt.% Depending on the process mode. The NKF content of the target fuel compositions was 86-88 wt.%, Of which the gasoline (NK 180 ° C) fraction was 20.6 wt.%, Kerosene (180-240 ° C) 18.5 wt.%, Diesel (240-360 ° C) 60.9 wt.%. The total content of the target products with a boiling point up to 360 ° C increased from 14.7 wt.% To 60-66 wt.% In terms of the starting product.

Example 5

Atmospheric-vacuum distillation of unused M - 8B oil (universal motor oil) showed the absence of gasoline and kerosene fractions in it, the content of the diesel fraction was 5.2%, the bulk of the oil was distilled in the boiling range of 380-500 ° C. Thermomechanical cracking of the test oil by this method led to the formation of about 20% gasoline, 10% kerosene and 43% diesel fractions, i.e. the content of the target products with a boiling point up to 360 ° C during processing by the proposed method increased from 5.2 to 73%. Thus, the fundamental possibility of thermomechanical cracking of high-boiling (above 360 ° С) oil components into target products with a boiling point up to 360 ° С was shown.

The study of the composition of the used oil M-8B, which was processed by this method, showed the presence of 19% gasoline, 15% kerosene and 38% diesel fractions in it. In general, the content of the target components with a boiling point of up to 360 ° C during the thermomechanical cracking of used oil was 72%.

The gas-vapor separation part (NKF) is a distillate containing gasoline, kerosene and diesel fractions, petrochemical products. It can be seen that the effect of the process according to the proposed method is significant: the content of fuel fractions with a boiling point of up to 360 ° C in the vapor separation phase (NCF) is approximately two times higher (in terms of the initial product taking into account the separation coefficient) than in the original oil. When using bottoms, waste oils, etc. as raw materials, the amount of light target products as a result of the application of the proposed method increases up to 15 times in comparison with the feedstock. The depth of selection of the distillate (the amount of the evaporated part of the hydrocarbons - NKF) depends on the temperature and flow rate of the coolant and raw materials, that is, on the technological mode of the process, as well as on the properties and composition of the raw material and the task. When using the proposed method at the installation, the depth of extraction of the evaporated part of the oil of the Vishenskoye field was reached - up to 85%, NGDU "Nurlatneft" - up to 80% (in contrast to the processing depth up to 30% with the classical method).

A promising option is that in which the vapor-gas part and the liquid part (intermediates) obtained after the separation apparatus, if necessary partially cooled, are mixed again. The resulting “synthetic” oil contains about two or more times more fuel fractions than the original product. In addition, if the density of the initial oil is 950 kg / m ³ (API = 17), then the density of the “synthetic” oil is reduced to 850 kg / m ³ (API = 35), and the kinematic viscosity, respectively, from 83 to 6 cSt. As a result of such an operation, the cost of “synthetic” oil increases significantly; it is easier to transport and process. This approach is especially promising for enterprises remote from refineries and producing heavy and viscous oil, such as, for example, in South America, Canada, and in some regions of Russia. In the same way, relatively cheap fuel oil and still cheaper bottoms can be processed into significantly more expensive high-potential oil.

In order to significantly intensify the process of evaporation and separation of the liquid and vapor-gas phases, the flow of hydrocarbons and high-temperature coolant is directed to devices for separating and increasing the interfacial surface of flows in the separation apparatus.

In order to optimize gas-vapor and liquid flows in the separation (evaporation) apparatus, to more clearly separate the liquid phase from the gas-vapor and rectification of the latter, internal devices such as distillation plates of various designs, nets, etc. can be built into the separation apparatus.

Thus, the design of the unit and the evaporation (separation) apparatus allows it to organize its operation in a continuous continuous mode with increased oil productivity, including heavy oil, of refining and petrochemical production residues, oil sludge and other liquid organic media (raw materials), and there is an increase depths further, after the processing and separation unit, processing by 1.5 ÷ 15 times (depending on the feedstock - heavy oil, fuel oil, etc.). Accordingly, the yield of the most valuable fuel compositions — gasoline, kerosene and diesel fractions, and petrochemical products — is also increasing.

Claims (6)

1. The method of preparation of liquid hydrocarbon feedstock, including the supply of feedstock and a heat carrier, their heating, separation of the feedstock into two parts - a light vapor-gas separation part (low boiling fractions of NKF) and a heavy part of separation (high boiling fractions of VKF), removal of separation products, characterized in that the raw material and the heat carrier are heated separately to the mixing stage, the raw material is heated to a temperature of not higher than 400 ° C, and the coolant is not lower than 300 ° C, the ratio of the flow of heat and raw materials is in the range of 1 ÷ 100, then the raw material and heat transfer They transfer to the stage of mixing and heating the raw material with a coolant, to supply the necessary heat for the implementation of the method, heat transfer processes are used in which the coolant is in direct contact with the raw material (the stage of mixing and heating of the raw material with a coolant), and liquid high-temperature organic coolants are used as the coolant, for example, part of a heavy the separation residue obtained directly during the implementation of this method, or inorganic coolants, for example molten salts, liquid metals, as well as high-temperature gas coolants, for example, light hydrocarbon fractions obtained by the implementation of this method, the mixture of raw materials and coolant is sent to the stage of processing by mechanical and wave action of a wide range of frequencies, and for processing using such devices, the action of which is based on hydrodynamic effects of the movement of multiphase media with velocities of more than 5 m / s along channels of various shapes, then the processed raw materials are sent to the stage of evaporation and separation into NKF (low-boiling fraction) and VKF (high-boiling fraction), NKF in the form of a gas-vapor stream are sent to the separation stage (droplet separation, filtration or rectification), after which the combined-gas phase of the NKF is sent for processing to obtain light oil products, the liquid fraction separated at the NKF separation stage ( the filtrate) is returned to the reprocessing stage for mixing and heating the raw material with a coolant to additionally obtain light products, the heavy part of the separation (high boiling fractions of VKF) in the form of a liquid flow pour to the stage of separation from the coolant, the coolant is directed to the heating phase of the coolant and then to the stage of mixing and heating of the raw materials, the liquid phase of the VKF separated from the coolant is sent to the processing and production of heavy commodity products, heat exchangers in which the coolant is in direct contact with the raw material, and devices for heating the coolant form a closed loop for the circulation of the coolant, and the stage of mixing and heating of raw materials with a coolant, processing mechanical and wave air ystviem, evaporation and separation into a vapor and a liquid phase, and separating NKF combined in one apparatus, wherein simultaneously carried thermomechanical cracking process. 2. The method according to claim 1, characterized in that the VKF after the stage of separation from the coolant is sent to the stage of selection of the light part (distillation) from VKF, which is returned to the reprocessing stage of mixing and heating the raw material with coolant to additionally obtain light products, the remainder after stages of the selection of light distillation from VKF are sent to the processing and receipt of heavy commercial products. 3. The method according to claim 1, characterized in that the vapor-gas phase of the NKF and the liquid phase of the VKF are sent to the cooling stage and then to the stage of transportation to the place of final processing and obtaining marketable products. 4. The method according to claim 1, characterized in that the vapor-gas phase of the NKF and the liquid phase of the VKF are sent to the mixing stage to obtain a high-potential "synthetic" oil. 5. The method according to claim 1, characterized in that the feedstock is subjected to mechanical and wave processing before the mixing step. 6. The method according to claim 1, characterized in that the coolant is subjected to mechanical and wave processing before the mixing stage.

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