SU610856A1 - Method of obtaining gasoline fractions - Google Patents

Description

The invention relates to methods for producing gasoline fractions by atmospheric distillation of petroleum and can be used in the petroleum refining industry. Methods are known for producing gasoline Bfcix fractions by atmospheric distillation of oil using a single atmospheric column. L. The processing of oils with a high content of low-boiling components in this way is difficult due to the increased load on the apparatuses. Closest to the invention is a method for producing gasoline fractions by atmospheric distillation of oil successively in two distillation columns fz. A light gasoline fraction is taken from the top of the first column. The residue from the first column, semi-petrol oil, is fed through a furnace to the main atmosphere (a column one, the column from which the rest of the gasoline fraction is taken, light products and fuel oil. The disadvantage of the method is the insufficiently clear separation of the two gasoline fractions. The purpose of the invention is to improve the quality target products. The goal is achieved by the described method of obtaining gasoline fractions by atmospheric distillation of oil successively in two atmospheric columns with the selection of the gasoline fraction with boiling 28-180 ° C from the top of the second column and returning; 3-5% by weight of the latter from the feedstock to the concentration section of the first column. The distinguishing features of the method are selection of the above gasoline fraction from the top of the second column and returning the latter 3 -5% by weight of the feedstock to the concentration section of the first column. The drawing shows a diagram illustrating the method. The feedstock enters the atmospheric column 1 via line 2, the benzium fraction (B-1) is taken from the top of column 1 through cooler 3 lines 4, hour which is used as acute reflux and returned to the column via line 5. Semi-petroleum gas is withdrawn from the bottom of column 1 via line 6, heated in a furnace 7, and through line 8 is sent to the main atmospheric column 9. A portion of the heated oil is returned to the E column 1 along line 10 as a hot stream. Water vapor is fed to the bottom of column 1 through line 11. From the top of column 9 through line 12, take the gasoline fraction (recycle), which is cooled in refrigerator 13 and returned to the concentration part of column 1 via line 14. The hour of this fraction is used as cold irrigation of column 9 and returned to the last line 15 With an increase in the amount of recirculation, the clarity of separation of gasolines increases, but the load on the columns also increases. The amount of recycle in the process described is 3-5% by weight of oil. From the main atmospheric column, side columns select the gasoline fraction (B-2), 17, the kerosene fraction, 18 and 19, the diesel fraction, and 20 maize, respectively, along the lines. Downstream column 9, steam 21 is fed through line 21. Example. The raw material used is a mixture of West Siberian oil from 0.851. Column mode of operation Column 8 Column Pressure in the feed zone, atm Heating temperature of raw materials, s Top temperature, s Bottom temperature, C Amount of water vapor,% for oil Steam temperature, ° C 180 180 Amount of acute irrigation,% for oil13, 3 25 Acute irrigation temperature, ° C 40 40 Gasoline sampling, oil% 8.1 7.9 Downstream of the column 1 is not hot. The amount of recycle is 3% by weight of oil. Gasoline quality and recirculation Content of target components (NC-85 C) in B-1, wt.% 97.4 (94.2) Content of target components (85-180 C) n B-2, wt.% 95.47 (92.17) Content of low-boiling contaminating components (NK-85 ° C) in B-2, wt.% 4.5 (7.8) Content of high-boiling contaminating components (85 ° С-КК) в B-1, wt.% 2.6 (5.8) Content of high-boiling 1x contaminating components (1800С-КК) in B-2, wt.% 0.03 (0.03) Content of components (НК-85С) in recirculation, wt.% 33.3 Content of components B-2 (85-180С) in recirculation, wt.% 66.7 The corresponding data of the known method is given in parentheses. The table shows the composition of the gasoline produced, as well as the composition of the recirculated material.

0.12 0.25 1.38 2.41 4.92 7.42

0.07 10.6 0.32 0 38.2

0.12

0.25

1.38

2.41

0.12

4.8

7.20, 22 0.46

10.2 2.6

Claims (2)

35.9 Thus, the described method allows to obtain better-quality target products by improving the clarity of separation. Claims method for producing gasoline-free fractions by atmospheric distillation of oil successively in two atmospheric columns, characterized in that, in order to improve the quality of the target prolongation of the duct table, the gasoline fraction with boiling point 2a-1yO.C from the top of the second column in an amount of 3-5 weight .% of the feedstock is returned to the concentration section of the first column. Sources of information taken into account during the examination: 1, I.L. Technologists of oil and gas processing, M., Himi, 1972, p. 296-298. 2. Bagirov B.T. Modern installations of primary oil refining, M., Khimi, 1974, p. 29. 13. rs