RU67088U1 - UNIT AND EVAPORATION UNIT FOR PREPARATION OF OIL AND OTHER HYDROCARBON MEDIA - Google Patents

Abstract

The invention relates to the field of preparation of liquid hydrocarbon raw materials for further processing and can be used in the production of hydrocarbon fuels.

The invention allows to increase the yield of light products during further processing, reduce energy costs per unit of production and reduce the quantity and cost of complex processing equipment.

The technical result, which is achieved by the claimed utility model, is to increase the intensification of the process of evaporation of oil fractions while maintaining the simplicity of the design in manufacture and operation. The technical result is achieved by the fact that in the block and the preparation apparatus high-temperature coolants are used. When using a high-temperature coolant, it becomes expedient to organize its circulation circuit, i.e. training unit. As a coolant, it is possible to use media immiscible with oil, for example, liquid metals, molten salts, high-temperature organic and gas coolants.

This goal is achieved in that the use of high-temperature coolants can significantly intensify the heat transfer processes occurring in the unit and the preparation apparatus, increase the temperature of the evaporation process and increase the yield of light products. 10 s.p. f, 5 ill.

Description

The utility model relates to the preparation of oil (including heavy), fuel oil, oil sludge, waste oils and other liquid hydrocarbon media for further processing and can be used in the production of hydrocarbon fuels.

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 oil-only (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 to reduce the pressure at the inlet of the feed pump, relieve the furnace from heating of 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.

Recently, in connection with the trend of oil refining at the place of its production, the demand for oil refineries of relatively low productivity is growing - 5-500 thousand tons of oil per year or more. 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 the heat transfer conditions are significantly worsened. This process is significantly accelerated with increasing temperature of the coolant. Therefore, devices of this type have

restrictions in terms of intensification of the process of evaporation of oil fractions. The temperature of the process is 200-230 ° C. This temperature corresponds to a certain evaporated part of the oil.

During the boiling process of oil and evaporation of fractions, droplets of liquid are present in the removed vapor phase. Separators of various designs are designed to separate them from the gas phase. The separator is located next to the evaporation apparatus or is not used to simplify the design and operation.

The technical result, which is achieved by the claimed utility model, is to increase the intensification of the process of evaporation of oil fractions while maintaining the simplicity of the design in the manufacture and operation, as well as to increase the depth of processing of liquid hydrocarbon raw materials and increase the yield of light fuel fractions and petrochemical products. 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 amount of oil that is evaporated quantitatively, that is, to increase the temperature of the process. An increase in the temperature of the process is also possible using the claimed utility model.

The technical result is achieved by the fact that in the separation apparatus comprising a housing, heat exchange devices for oil evaporation and input / output fittings for working and product media, heat exchange devices are designed in such a way that heat is transferred from the heat carrier not through the dividing wall, but when the heat carrier is in direct contact and oil. 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 performance of the device. In addition, direct contact of the media leads to intense heat transfer. The result of this 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. Accordingly, the temperature of the evaporation process can be increased, if necessary, from 200-230 ° C to 400-450 ° C and more, which allows thermal and thermomechanical (using cavitation, sound and ultrasonic processing of raw materials in special devices, for example, hydrodynamic type) cracking simultaneously with the evaporation (separation) of oil or other hydrocarbon feedstocks. This, in turn, allows you to increase the depth of processing of raw materials and the yield of light (fuel) fractions and petrochemical products, reduce energy costs per unit of production and reduce the quantity and cost of complex technological equipment.

When using a high-temperature coolant, it becomes expedient to organize its circulation circuit, i.e. training 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 exchangers of direct heating through the input fitting, to which the feedstock is also fed. As a coolant, it is possible to use media immiscible with oil, for example, liquid metals, high-temperature organic and gas coolants.

The block diagram of the preparation is shown in figure 1. Desalted and dehydrated (at least partially) oil or other liquid hydrocarbon feeds are pumped through pump 3 through heat exchangers of various designs 5 and 6, for example, air cooling units ABO or recuperative heat exchangers, through the inlet to the preparation apparatus 2. Also into the preparation apparatus through the inlet coolant circulating through the circuit using pump 4: preparation apparatus 2, heating furnace 1, in which the coolant is heated to the desired temperature, preparation apparatus 2. In the preparation apparatus 2, coming direct heating of the feedstock heating medium due to their direct contact heat exchange devices in direct heating. Light oil fractions (intermediates) evaporated in a separation (evaporation) apparatus are supplied in a gas-vapor form to a recuperative heat exchanger 6, in which the feedstock is partially heated, then to an air cooling apparatus 7 and to a condenser 8, in which it is finally cooled to a liquid state and exited the preparation unit in the form of a wide fraction of distillates, which is basically a mixture of gasoline, kerosene and diesel fractions. The liquid part of the separation (intermediates), i.e. the non-evaporated part, which is close in composition to the tar, is fed to a recuperative heat exchanger or ABO 5 and leaves the preparation unit for further use.

A wide fraction of distillates (SHF) can be sold for processing as high-potential expensive oil (the content of light fuel compositions - gasoline, kerosene and diesel fractions is about 90%), similar in composition to gas condensate, or, by completing the preparation unit with a unit for the production of commercial products, standard refinery refinery (figure 2, figure 3, position 9) - blocks of atmospheric or atmospheric vacuum tubes, a unit for the production of commercial gasoline and diesel fuel (hydrotreatment, bl to reforming, etc.) to process it on-site training. Moreover, the preparation unit can be located both directly in front of the atmospheric or atmospheric vacuum tube blocks (Fig. 2), and immediately after them (Fig. 3). If block

of preparation is located after an atmospheric or atmospheric vacuum tube (Fig. 3) and hot bottoms (fuel oil) are fed to it, then its heating in the furnace may not be used and fuel oil, bypassing the heating furnace, is immediately fed to the preparation apparatus.

The liquid part, or separation residue (OR), depleted in low boiling fractions, can be sold as raw materials for the production of bitumen, bitumen emulsions, coatings, etc., or, by completing the block with a bitumen block (figure 2, figure 3, position 10) getting commodity bitumen at the training site.

A promising option is a block in which the vapor-gas part and the liquid part (intermediates) obtained after the separation apparatus, if necessary partially cooled, are mixed again on the mixing block (Fig. 4, position 11). 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 decreases to 850 kg / m ³ (API = 35), and the kinematic viscosity, respectively, from 83 cSt 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. There are other options for schemes of oil refineries with a separation apparatus.

If the heavy residue and a wide fraction of distillates are processed on site, the recuperative heat exchangers 5 and 6, the air cooler 7 and the condenser 8 may not be used in whole or in part in the preparation unit circuit.

The evaporation (separation) apparatus for the preparation of oil, including heavy oil, residues of oil refining and petrochemical industries, oil sludge and other liquid organic media (raw materials) for further processing and obtaining marketable products is the main apparatus of the preparation unit, without which the preparation unit cannot be operational .

The essence of the separation apparatus is illustrated in Fig.5.

This figure shows a diagram of the separation apparatus. Into the apparatus, through appropriate fittings, into heat-exchange devices — turbulent dynamic evaporators (FIG. 5, position 1) — oil and coolant are continuously supplied, where they are in direct contact and mixing. From the apparatus also through the appropriate fittings output: low-boiling oil fractions in the form of a vapor-gas phase (a wide fraction of distillates), the remainder of the oil separation in the form of a liquid phase

(high boiling fractions) and coolant. From the separator (figure 5, position 2), the captured liquid is drained into the lower part of the apparatus. To improve droplet separation from the vapor phase during its removal from the apparatus body, the vapor phase separator is placed in the volume of the apparatus body. The trapped drops coagulate and the liquid flows into the lower part of the apparatus. In addition, the placement of the separator in the volume of the separation apparatus leads to a significant reduction in heat loss.

The coolant from the apparatus is fed into the heating furnace and then again sent to heat exchangers. The separator - sump (figure 5, position 3) at the bottom of the separation apparatus serves to separate the liquid phase of the separation of oil from the coolant.

As a heat carrier it is possible to use media immiscible 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 B.S., Genin L.G. , SA Kovalev. Heat transfer in nuclear power plants. M., "Energoatomizdat", 1986, p.22-23). For example, the boiling point of sodium is 883 ° С at atmospheric pressure, i.e. sodium can be heated to 500-700 ° C at pressures close to atmospheric, which exceeds the temperature required for thermal or thermomechanical cracking of the feedstock during its in-depth processing, and low pressure allows you to reduce the cost of equipment and capital costs.

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 VG 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 mixture should be no lower than 4: 1, and preferably 5: 1 or more. At industrial costs of the hydrocarbon mixture, a large steam boiler and a steam superheater up to 600-650 ° C 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 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 high pressure has its serious drawbacks, although the use of such coolants is much more advantageous than the use of steam heat carrier and gives good results, especially if gas is used as the heat carrier, obtained directly during the separation of raw materials by this 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 to oil to obtain a good separation result should be 5: 1. 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 drawbacks, for example, associated with the use of pumping equipment, problems of starting-up operations (transferring the coolant to the molten molten state), etc., although the use of such coolants allows one to obtain good results. Therefore, the most convenient and practical heat transfer media are high-temperature organic 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 silicon-organic heat carriers. M., "Energy", 1975, S. 62-72).

In order to avoid the above disadvantages, this method proposes, as the main, most simple and optimal option, to use a heavy separation residue of a liquid hydrocarbon feedstock (liquid separation phase), the necessary part of which returns to the beginning of the process, as an organic coolant. The use of a heavy separation residue as a coolant (it does not need to be specially prepared or purchased, it appears during the implementation of the method), which is a high-temperature coolant, makes it possible to increase the operating temperature in the separation apparatus, intensify thermal or thermomechanical cracking and, accordingly, increase the processing depth and the yield of light products is higher than their potential content in the feedstock.

Before starting the process of separating oil or another mixture of hydrocarbons, 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 mixture of hydrocarbons. The simplest method, which is used during operation of the unit and the separation (evaporation) apparatus, is as follows. The required amount of mixture

hydrocarbons are 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 feedstock) 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. (When using other coolants (gas, liquid metal), this pre-start step is not needed. The finished coolant is heated when it circulates along the circuit of the furnace - separation apparatus - furnace, and when the required temperature of the coolant is reached, the raw material is supplied to the apparatus and the process begins, as indicated below.)

Then the oil (or other raw materials) and the coolant are fed into a turbulent dynamic evaporator (figure 5, position 1), where they are in direct contact and the raw materials are heated. A vapor-liquid mixture arises at the outlet of the evaporator. The vapor-gas phase, which contains mainly light (fuel products and petrochemicals) fractions of evaporation and separation of oil or other hydrocarbon feeds, is removed from the upper part of the separation apparatus for further processing, for example according to the fuel version, or for other use. Part of the liquid phase - the separation residue is removed from the nozzle at the bottom of the apparatus and sent also for further processing, for example, to obtain marketable bitumen, or for other use. The remainder of the liquid phase — high-temperature organic coolant — is removed from the separation apparatus and fed to the furnace to be heated to the desired temperature, then returned to the beginning of the process — to a turbulent dynamic evaporator (Fig. 5, position 1). There can be several turbulent dynamic evaporators in one device. The essence of the operation of the unit and the separation apparatus is also illustrated in figures 1-5. In the case of using high-temperature organic liquids as a coolant, in particular, a heavy separation residue, a separator-settler (Fig. 5, position 3) at the bottom of the separation apparatus is used to clean the coolant from coke-like particles that may occur during the evaporation and separation of oil at high temperatures , and other mechanical impurities.

The utility model is implemented on a bench installation. The following are some of the results of the separation (evaporation) process obtained on a bench installation. Feedstock - oil deposits of the Ulyanovsk region. Separation effect: SHF - 74% of the mass., OR - 23% of the mass., Gas yield - 3% of the mass. The enlarged fractional composition of oil and HFD (in terms of initial oil, taking into account the separation coefficient) is shown in the table.

Table
Acceleration of oil and HF according to GOST 2177 (% volume) Options n.k. ° C It is distilled off (in% vol.) To a temperature, ° С 120 140 150 160 180 200 220 240 250 280 300 Source oil 71 6.5 8.5 9.5 10 13 16 eighteen 22 24 thirty 33 ShFD oil separation 57 16 24 29th 34 42 51 60 67 70 78 84

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 the 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, Rashig rings, nets, etc. are built into the separation apparatus.

Thus, the design of the unit and the evaporation (separation) apparatus allows you to organize its operation in a continuous continuous mode with increased oil productivity, including heavy oil, residues of oil refining and petrochemical industries, oil sludge and other liquid organic media (raw materials) at a process temperature of in the range up to 400-450 ° С and higher, while there is an increase in the depth of the further, after the preparation unit, processing by 1.5 ÷ 2 times or more (depending on the composition of the feedstock). Accordingly, the yield of the most valuable fuel compositions — gasoline, kerosene and diesel fractions, as well as petrochemical products — also increases.

Claims (10)

1. The evaporation unit for the preparation of oil and other liquid hydrocarbon media, containing a heating furnace, pumping and heat transfer equipment, characterized in that the preparation unit is added an evaporation apparatus, and the coolant is placed in a closed circuit evaporation apparatus - heating furnace - evaporation apparatus, and in as a heat carrier, a high-temperature gaseous or inorganic coolant, or a high-temperature organic coolant, in particular a heavy evaporation residue, obtained not Directly in the apparatus, and also as a coolant, a medium is used that is not miscible with oil and does not dissolve in it. 2. The block according to claim 1, characterized in that for on-site processing of the semi-products obtained in the preparation block, the blocks for the preparation of marketable products are added to the preparation block - an atmospheric or atmospheric vacuum tube block, a hydrotreating block, a reforming block, a bitumen production block, etc. ., and the preparation unit can be located immediately before the atmospheric or atmospheric vacuum tube unit, and immediately after them. 3. The block according to claim 1, characterized in that in order to obtain a high-potential and synthetic oil depleted in harmful impurities, a mixing block is added to the preparation block for mixing the semi-products leaving the block. 4. The evaporation apparatus for the preparation of oil and other liquid hydrocarbon media, comprising a housing, heat exchangers for oil evaporation, a gas-vapor mixture separator and fittings for input-output of working and product media, characterized in that for supplying the necessary heat to the evaporation zone of low-boiling oil fractions heat exchange devices are used in which the coolant is in direct contact with oil, and a high-temperature gaseous or inorganic coolant is used as the coolant spruce, or a high-temperature organic coolant, in particular a heavy evaporation residue obtained directly in the apparatus, and also a medium that is not miscible with oil and does not dissolve in it is used as a coolant. 5. The apparatus according to claim 3, characterized in that a separator-settler is integrated at the bottom of the separation apparatus to separate the liquid separation phase from the coolant. 6. The apparatus according to claim 3, characterized in that a separator-settler is integrated in the separation apparatus body for cleaning the heat carrier from coke-like particles and other mechanical impurities. 7. The apparatus according to claim 3, characterized in that the gas-vapor mixture separator is built directly into the housing of the separation apparatus. 8. The apparatus according to claim 3, characterized in that in order to increase the yield of light fuel products, the hydrocarbon feed in the apparatus is subjected to cavitation, sound and ultrasound effects on special devices, for example, hydrodynamic ones. 9. The apparatus according to claim 3, characterized in that devices for separating the liquid and vapor-gas phase of evaporation are integrated in the apparatus. 10. The apparatus according to claim 3, characterized in that in order to optimize the gas-vapor and liquid flows in the apparatus, to more clearly separate the liquid phase from the gas-vapor and rectification of the latter, internal devices are built into the apparatus, such as distillation plates of various designs, Rashig rings, nets, etc. .