JPH01500439A - Method for continuous processing of vacuum distillation residue in crude oil refineries - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Method for continuous processing of vacuum distillation residual oil in crude oil refineries (Technical field) This invention relates to a method for continuously processing residual oil remaining after vacuum distillation in a crude oil refinery. do.

(background technique) Approximately 550°C (standard pressure) after the final crude oil fractionation step, which is carried out under vacuum in the refinery. Below, substances that do not evaporate remain in the distillation residue. This distillation residue is normal - the origin of the crude oil It corresponds to 25 inches of crude oil supply. The continuous treatment is actually solvent treatment, For example, this can be done by deasphalting propane. This removes residual oil from solvent-soluble oil. The first fraction containing lubricating oil and wax and asphalt insoluble in solvent, asphalt It is separated into a second fraction containing phaltenes and the like. The amount obtained in this case is of the second fraction. There are many people. Valuable non-fuels such as lubricating oil and wax can be obtained from the first solution fraction. or feed them to a cracker to obtain low-boiling products. Wear. The second fraction or precipitate, which is insoluble in the solvent, is or as refinery fuel in situ or after mixing of light fractions for liquefaction. It is used as a heavy fuel outside the plant, for example in a power plant.

Using solvents to purify vacuum distillation residues results in various problems and limitations. melt Low-value asphalt-containing distillates that remain undissolved after treatment with agents, often vacuum residues In the case of heavy oil, it can be more than 40% of crude oil. Large like this The amount of components exceeds the refinery's fuel demand. The second use of insoluble fractions, Tsumasibichii In the production of aluminum, asphaltene and asphaltene, which exist as colloids in crude oil, are Problems arise because the ruts precipitate during solvent treatment. How to make bichinimen Complete redispersion is essential, but often this is no longer possible and cannot be obtained The product becomes less valuable.

Furthermore, even with solvent treatment, lubricating oil and wax components cannot be completely dissolved, while polymer The ingredients dissolve first, which is detrimental to the final product that is subsequently obtained. into the distillate, e.g. increasing the coking of the lubricating oil obtained from it. .

Additionally, the use of low-boiling solvents requires special safety measures, especially expensive instrumentation. becomes. Solvent recovery consumes energy and is expensive due to the large solvent/resid ratio. It costs a lot.

European patent specification No. 66790 describes a method for molecular distillation of crude oil refinery residue. . There, both the evaporation pressure and the condensing surface temperature decrease from the supply section to the residual oil extraction section. . To improve energy balance, vacuum distillation residual oil does not supply any energy. The vaporizer is supplied to the molecular distillation section from one feed section having a resid temperature of -vacuum distillation resid. Heat generation is extracted and this necessarily leads to cooling in molecular distillation and therefore This is reflected in the temperature being lower than in the case of vacuum distillation.

According to German Patent Publication No. 3122650, molecular distillation is carried out in oil refineries. The yield of decomposable components is increased by application. At the same time, it eliminates the usual solvent extraction be able to. By reducing the operating pressure, the distillation temperature can be significantly lowered, allowing It becomes possible to carefully distill components with high boiling points. Heating takes place prior to molecular distillation. The residual oil resulting from vacuum distillation is used, from which the heat of vaporization is extracted and molecular distillation is carried out. is carried out at a lower temperature than the preceding vacuum distillation.

(Disclosure of invention) The purpose of the present invention is to provide a method for vacuum distillation of crude oil that is more economical than the previously described methods. The purpose of the present invention is to propose a method for molecular distillation of residual oil produced from Molecular distillation is not included in the invention. do not have.

Surprisingly, thin-layer molecular distillation of vacuum-distilled residues results in increased energy consumption. The economic efficiency will improve significantly, that is, the labor of energy balance will improve the economic efficiency. It was discovered that it brings According to the invention, the increase in energy consumption The distillation temperature is also increased by increasing the molecular distillation temperature. Due to this, the feed rate , thus the distillation capacity is significantly increased, but this comes at the expense of less valuable residual oil. This is done by simultaneously increasing the fraction.

Prior art extraction methods use non-polar solvents based on the polarity and chemical structure of the substance. A separation took place. In the well-known molecular distillation method, the vacuum residue is determined based on the boiling point temperature of the existing substance. Separated. According to the present invention, it is possible to avoid remaining in the low-value residual oil in the prior art. Due to the high temperature, valuable products are obtained along with the distillate. Therefore, according to the present invention In addition to the quantitative advantage of increasing the amount of valuable products, the use of fractions with different compositions , further qualitative advantages are thus also achieved.

Even more important than improving the distillate/resid ratio is the fact that increased temperature increases the and the feed rate per evaporation area can be increased several times. This will cause the book The economy of the method is significantly improved.

The difference in the so-called C/H ratio, that is, the carbon/hydrogen ratio, between distillate and residual oil can also be eliminated by the method of the present invention. It becomes quite large.

Further, according to the present invention, the residence time can be significantly reduced with very little variation and with great uniformity. A new shortening is guaranteed.

At the same time, due to the rise in temperature, residual oil containing concentrated polymer substances can be discharged without any problem. Become.

The lubricating oils obtained according to the present invention can be obtained even without additives by conventional vacuum distillation methods. It is used in the same way as lubricating oils whose viscosity is adjusted to the desired viscosity using expensive additives. be able to. Additionally, this distillate is virtually free of metal-containing components and has a low boiling point. Since point substances are produced, decomposition using catalysts that are sensitive to impurities will no longer be a problem. . Furthermore, according to the present invention, high-molecular aromatic hydrocarbons remain in the residual oil, which reduces the distillate. The quality of the oil is additionally improved and the colloidal asphaltenes in the residual oil are stabilized.

The asphalt-containing fraction, i.e. the resid of thin-layer molecular distillation, in this case compared to the prior art, Not only is the volume decreasing enough for refineries to fully utilize it as fuel; It also changes qualitatively, and it can be easily redispersed during the production of bicemen. Wear. This property may be associated, inter alia, with an increased content of polar components.

Besides, the fact that the residual oil no longer contains virtually any wax content means that the wax content is high. This is important in the case of crude oil, especially when it is used as bicemen/asphalt. Ru.

Thin layer molecular distillation or its instrumentation is known in process technology, mainly It was applied to carefully wash and recover heat-sensitive materials to prevent thermal decomposition. that On the other hand, in the present invention, thermal decomposition allows the desired valuable distillate to be obtained in large quantities. It is even desirable and possible on a small scale as long as a vacuum can be maintained.

According to the method of the present invention, boiling continues at approximately 550°C (standard pressure) or higher in a refinery. Residues that cannot be distilled and were traditionally considered final can now be distilled with quantitative and qualitative advantages. It will be done.

In this case, products of new composition with some new properties are obtained.

Further, according to the present invention, it contains approximately 50 grams of vacuum distillation residue, or more. from heavy oil, which is even and therefore hardly commercially available, to regular crude oil. The same amount of distillate can be obtained and is now also available for use.

The method of the invention can be carried out using known equipment for thin layer molecular distillation. Wear. These are installed in the final stage of the refinery, following the vacuum distillation process. thin layer Molecular distillation involves higher temperatures and pressures of approximately 10-1 to 10-1 than the previous vacuum distillation. s small. According to a particular embodiment of the invention, work is carried out with increasing temperature gradients. steaming When planning a vacuum with a large air volume, the evaporation surface and condensation surface should be placed as close as possible. It should be arranged accordingly. This is generally achieved by making the evaporation and condensation ranges coaxial. Ru. It is advantageous to arrange the evaporation surface and the condensation surface in the form of a vertical cylinder. The feed material is on the heating surface. Evenly distributed over the top to create a turbulent flow and the material flowing down the heated surface due to gravity The turbulent state is maintained until the

This allows the material heated by the entire heating surface to be immediately supplied to the liquid surface, resulting in low boiling point minutes evaporate.

A plurality of thin layer molecular distillation devices can be arranged in series or in parallel.

Example 1 The residual oil from the vacuum distillation process, which cannot be distilled at 530℃ (temperature is relative to standard pressure), is Buss AG's SAMVAC thin layer molecular distillation system It was supplied at the same time. Operational data is Supply speed: 151-/h Pressure: 4.5-10” mbsir Heating temperature: 351℃ Cooling source [IQ5’C Distillation rate 6.5] #/h The distillate content was 49.6 inches.

Residual oil is continuously fed to the evaporator inlet using a pump and is transferred using a rotary distribution ring. Evenly distributed on the inner surface. Next, the rotor and wiping plate, which moves along the evaporation surface, Grip it and add the irregular Rh film to the heating surface. Wave front (head wave) in front of rotor/wiping plate occurs.

Although the throughput and the amount of distillate could be significantly increased by increasing the heating temperature, This can be attributed inter alia to the evaporation of polymeric substances.

Data of other examples are summarized below. Examples 1 to 5 have increased distillate content , and Examples 6 to 10 were carried out with consideration given to increasing the supply rate.

Example Supply 2 3 4 5 Supply speed kf/h 2t5 247 1 & 5 158 Storage tank temperature 'C2012 05206205 Supply pipe temperature °C 175 189 183 520 Concentrate Outlet speed kf/h 13145 17.9 &5 7.27 Outlet speed kg/h aos aa 7.0 453 vacuum mbar AXID-"4X10-" 35X10" 5X10" Heat medium inlet temperature °C 552 329 553 550 Heat medium outlet temperature 1:: 312 313 319 355 Coolant inlet temperature °C 93 95 95 105 Coolant outlet temperature °C 94 96 97 105 Output fraction % 37.4 350 4S2 4z4 Example Heating temperature Distillate fraction Feeding speed A °C %/supply amount positive/h 7 371 56 39, 6 8 374 61 2 3 9 386 63 59, 7 10 594 6t5 5L3 Easily achieves throughput speeds of 225 kt/hm'' as shown in these experiments economical use at refinery scale is guaranteed.

(Brief explanation of the drawing) The present invention will be further explained based on FIGS. 1 and 2. The above using the illustrated experimental setup An experiment was conducted.

Figure 1 is a flowchart of the distillation section of a crude oil refinery.

FIG. 2 shows an apparatus for carrying out the method of the invention.

(BEST MODE FOR CARRYING OUT THE INVENTION III) In Figure 1, crude oil 1 of average quality is , is fed to a rectifier 2 operated under standard pressure. After evaporation, the supplied crude oil Approximately 50% is discharged from the apparatus as separated fraction 3.4.5. Residual oil 6 is fed to another rectifier 7 operating under vacuum, approximately 25 g of crude oil is reduced to fraction 8.9. ．． 11 and is ejected from there. The non-distillable residual oil 12 is then processed according to the invention. It is supplied to the subsequent processing section and the thin layer molecular distillation section. There, distillate 14 and non-distillable A functional residual oil 15 is obtained. Distillate 14 is fed to a cracker to obtain low molecular products or can be further separated into lubricating oil and wax. Residual oil 15 is essential oil It can be used as fuel at the site or it can be further processed to become tar.

The apparatus according to FIG. 2 for carrying out the method of the invention has a charging tank 21 with a stirring device 22. M is an electric motor attached to each device in the diagram. Charging tank 21 is a supply pump The evaporator itself is connected to a molecular evaporator 25 via a line 24 with 23, and the evaporator itself It is connected to a receiving tank 26 and a distillate receiving tank 27. In addition, the molecular evaporator 25 has two series Cold traps 28 and 29 are connected. Lure between cooling traps 28 and 29 2 vacuum pump 31, and a Roots vacuum pump 32 behind the second cooling trap. A vane vacuum pump 33 is arranged behind it.

The residual oil from the vacuum rectification stage introduced into the charging tank 21 is passed through the pipe line 24 by the pump 23. The oil is introduced into a molecular evaporator 25, where it is separated into a distillate and a residual oil by evaporation, and then sent to a receiving tank. 26, which is separated and collected in cold traps 28,29. ) The heating temperature for thin layer molecular distillation according to the present invention is higher than the temperature described in the above examples. be able to. A temperature of 400°C or higher is preferred.

international search report ANNEX To hKE INTER, NATIONAL 5EARCHRE PORT 0NDE-A-312265023/12/82 NonaFor more data is ak+out this ar+nax!

Claims (13)

[Claims] 1. In a method for continuously processing residual oil left after vacuum distillation in crude oil refineries, Thin-layer molecular distillation of residual oil is carried out under air, and the temperature of the evaporation surface is the same as that of the residual oil remaining during vacuum distillation. A method characterized in that the distillate and the concentrated residual oil are separated and discharged at a temperature higher than . 2. The temperature of the evaporation surface is 50°C, preferably 80°C, higher than the temperature of the residual oil remaining during vacuum distillation. 2. A method according to claim 1, characterized in that the temperature is higher than 100[deg.]C. 3. Claim 1, characterized in that the thin layer of the raw material to be distilled is configured as a turbulent thin film. The method described in Section 1. 4. Claim 3, characterized in that mechanical means are used to create turbulent flow in the thin film. Method described. 5. Claim 4, characterized in that a wiping plate is used to create a turbulent flow in the thin film. How to put it on. 6. It is characterized by treating vacuum distillation residual oil with a boiling point of 550°C or higher at standard pressure. A method as claimed in any one or more of the preceding claims. 7. Absolute pressure of 10 mbar or less to 10 −3 mbar or more, preferably 1 to 0.01 Any of the preceding claims characterized in that the work is carried out in the vacuum region of mbar. The method described in item 1 or items. 8. of the prior claim characterized in that a distillate is obtained that is virtually free of asphaltenes. A method according to any one or more of the ranges. 9. produced in multiple parallel-connected devices, each with one attached vacuum device. as set forth in any one or more of the preceding claims, characterized in that the Method. 10. The work must be carried out at a heating temperature of 350°C or higher, preferably 400°C or higher. A method as claimed in any one or more of the preceding claims. 11. Any of the preceding claims characterized in that the supply and the heating medium are passed in countercurrent. The method described in item 1 or items. 12. Any of the preceding claims characterized in that the work is carried out with increasing temperature gradients. The method described in item 1 or items. 13. The preceding claim is characterized in that the work is carried out with a substantially constant pressure gradient. The method according to any one or more of the following items.