SU1541237A1 - Method of producing oil fractions - Google Patents

Abstract

The invention relates to petrochemistry, in particular to the preparation of petroleum fractions. The goal is to increase the yield and improve the quality of vacuum distillates. The production is carried out by distillation of oil in an atmospheric column with the selection of low-boiling hydrocarbons from the top of the column, distillate fractions in the form of side straps and fuel oil from the bottom of the column. The oil is heated and separated in a vacuum column by refluxing the top of the column with the distillate fraction of the atmospheric column and vacuum distillate fractions and distillation residue are obtained. Two streams are additionally introduced into the distant section of the vacuum column from the atmospheric column, with the first stream of low-boiling hydrocarbon vapors from the top of the column being fed to the bottom of the distant section, and the second vapor stream of the distillate fraction of the atmospheric column is introduced above the first stream. The output of fractions 360 - 420 ° С and 420 - 520 ° С increases by 1.5 and 6.6%, respectively. 1 dw., 3 tab.

Description

This invention relates to a primary distillation technology and can be used in the refining industry.

The purpose of the invention is to increase the yield and improve the quality of vacuum distillate fractions of

The drawing is a process flow diagram.

The boiled off oil is heated in the furnace 1 and introduced into the complex atmospheric column 2 via line 3. The vapors from the top of column 2 are condensed in condenser k and fed through line 5 into the reflux tank 6. The condensate from the bottom of the tank 6 return line 7 for irrigation of the column 2. The remainder from the bottom of the column 2

heated in the furnace 8 and through line 9 are introduced into the feed zone of the vacuum column 10. From the top of the column 1C), non-condensable steam is discharged through line 11, the residue is removed from the bottom through line 12. From columns 2 and 10, distillation fractions are taken from lines 13-20. From the intermediate sections of columns 2 and 10 the circulation irrigations are withdrawn, cooled in heat exchangers 21-25 and, respectively, along lines 26-30, returned to columns 2 and 10. To the top of column 10, through line 31, part 32 is fed as irrigation the distillate fraction from the intermediate section of the atmospheric column 2. Another part of this fraction is by force

four

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heat in the heat exchanger 33 and injected through line 3 into the intermediate section of the distant section of the column 10, and the remainder of the distillate fraction is withdrawn from the plant through line 16. In addition, the flow of vapor from the top of the tank is directed to the bottom of the column 10 through line 35 6 irrigations of the atmospheric column 2.

Example 1. Boiled Oil

in the amount of 351.9 t / h, they are heated to ZbO ° C and fed into a complex atmospheric column 2. In the strengthening section of column 2 there are 32 plates. The efficiency of the plates is 0.6. The pressure of the top of the column is 0S07 MPa, the temperature of the top is 86.1 С, the bottom of Зb6.2 ° С. The pressure drop on the plate is 0.001 MPa.

Gasoline is removed from the top of column 2 in the vapor phase, condensed in a condenser-cooler and supplied to reflux tank 6, from where part of the condensate is returned to the top plate of the column as reflux, and 15 t / h of gasoline excess is removed from the column . From the seventh plate (counting from the top) of the column, the ligroin fraction is removed and fed to the otlarny section, the vapors from the top of which are returned to the same plate of the column, and the Vt / h of the steamed ligroin fraction is removed from the column. From the twelfth plate of the column, the first circulation irrigation is removed, cooled in heat exchangers and returned to the twelfth plate of the column at a temperature of 110 ° C. 38 th / h of the kerosene fraction were extracted from the thirteenth plate, and 83.8 tons / h of diesel fuel from the eighth over the plate. From the twenty-fourth plate of the column, the second circulation irrigation is removed, cooled in heat exchangers and returned to the twenty-fourth plate of the column at a temperature of 190 ° C. Atmospheric gas oil in the amount of 5.2 t / h is output from the twenty-sixth plate of the column.

201.8 t / h% fuel oil is withdrawn from the bottom of column 2, heated in an oven and fed to the power supply zone of the vacuum column 10. There are 21 contact devices in the column, of which five are contact devices in the distant section. The pressure of the top of the column is 2.5 kPa, the pressure drop over the contact device is 0.13 kPa. The efficiency of the contact devices of the securing section is 0.88, the distant section is 0.8. From the top of the column 10 withdrawal

0

d t non-condensable steam in the amount of 0.3 t / h. A fraction of diesel fuel is withdrawn from the third contact device (counting from the top of the column), part of which is pre-cooled to 0 ° C and returned to the first contact device of the column as irrigation. After the cooling to 40 ° C, 80.8 t / h of diesel fuel from atmospheric column 2 is fed to the first contact device via line 31 as irrigation, which is discharged from the third contact device (counting from the top) of the vacuum column together with the flow of diesel fuel of this column . From the fifth contact device the fraction is withdrawn, part of it is cooled in the heat exchanger up to 80 ° C and returned to the fourth contact device as irrigation. From the twelfth contact device a fraction of 20-520 ° C is withdrawn, part of it is cooled in heat exchangers to a temperature of 80 ° C and returned to the eleventh contact device as a reflux of the column. At the same time, two fractions are fed into the distant section of the vacuum column 10 from the atmospheric column 2 in two streams, the hydrocarbon composition corresponding to the distillation fractions of the vacuum column. Thus, 0.1 t / h of the steam-1 stream discharged from the top of the reflux tank of the atmospheric column 2 is fed to the bottom columns 10 through line 35. Above the inlet of the specified steam flow, a portion is fed to the intermediate section of the stripping section of the column 10 Diesel fuel fractions from atmospheric column 2, preheated in heater 3, in an amount of 3 tons / hr, and the remainder, as indicated above, is used as a reflux to the top of the same column. From the bottom of the column receive 106.5 t / h of tar.

The main indicators of the operation of the vacuum column 10 are given in Table 1, the fractional composition of the separation products is given in Table 2.

Example 2 (by a known method). The process is carried out under the conditions of Example 1, with the exception of supplying the evaporating agents to the bottom of the column 10 along lines 3 and 35, with this column operating without the stripping section.

The fractional composition of raw materials and separation products is given in table 3.

The proposed method, in comparison with the known, allows for processing the same amount of fuel oil to increase the yield of distillate fractions and improve their quality. Thus, the yield of the ZbO-20 ° C fraction increases by 1.5%, and the fraction of lt20-520 ° C increases by 6.6% (Table 01). At the same time, the content of components boiling to ZbO ° С in the fraction decreases from 2.7 to 2.3 wt.%, In the fraction 20-520 ° С the amount of fraction n.k. 20 ° C is reduced from 23.0 to 22.1 wt.%, And the residue decreases the content of the nc fraction. 520 ° C from 11.2 to 7.5 wt.% 1 (Table 2).

Thus, the use of the proposed method in practice will allow an increase in the productivity of the installation while at the same time improving the quality of the target products.

Claims (1)

The invention method of obtaining petroleum fractions by distillation of oil in an atmospheric column with the selection of low-boiling coal. hydrogen from the top of the column, distillate fractions in the form of side straps and fuel oil from the bottom of the column, heating and separating the fuel oil in the vacuum column by refluxing the top of the column with a distillate fraction of the atmospheric column and obtaining a vacuum distillate fraction and distillation residue, characterized in that , in order to increase the yield and improve the quality of vacuum distillates, two streams are additionally introduced into the distant section of the vacuum column from the atmospheric column, with the first stream of light boiling hydrocarbon vapors from the top of the column being fed at the bottom of the distant section, and the second vapor stream of the distillation fraction of the atmospheric column is introduced above the first stream. Table 1 15 12378 Continuation 0 is the ratio of the amount of steam flow (t / h) received at the entrance of the fuel into the vacuum column 10, to the total amount of fuel oil (t / h). Spreadsheets 15 1237 | 0 Table}