SU1736999A1 - Method of producing diesel fuel - Google Patents

Abstract

Application: oil refining. SUMMARY OF THE INVENTION: The diesel fraction is subjected to catalytic hydrogenation in the presence of 0.5-1% by weight of gasoline distillate, obtained during the distillation of hydrogenate of the initial diesel fraction. 2 tab. .

Description

The invention relates to methods for producing purified diesel fuel and can be used in the oil refining industry in diesel hydrotreatment installations.

A known method for producing purified diesel fuel by hydrotreatment of diesel fractions and subsequent distillation of hydrogenate with the formation of purified diesel fuel and gasoline distillate. The stripping of diesel fractions in the distillation column from hydrogen sulfide is carried out with water vapor. The yield of purified diesel fuel is 94-95%.

However, according to this method, up to 2-3 wt.% Of low-quality gasoline distillate is formed, which has a high boiling point, a low octane number, a high concentration of hydrogen sulfide. At the plant there are serious difficulties in the processing of this gasoline distillate. In addition, stripping with water vapor leads to increased energy consumption and ingress

water to diesel, which during drainage increases the loss of diesel fuel.

The closest to the invention to the technical essence and the achieved effect is a method of obtaining purified diesel fuel, including catalytic hydrogenation of the diesel fraction and the subsequent rectification of the hydrogenate to form purified diesel fuel and gasoline distillate, with the residual catalytic cleaning product of gasolines in the raw material of the hydrotreating unit being introduced in the amount of 0 , 5-0.3 wt.%. The yield of purified diesel fuel increases to 97.1 wt.%. The stripping of the purified diesel fraction from hydrogen sulfide in the distillation column is carried out with water vapor.

However, the known method is characterized by an insufficiently high yield of purified diesel fuel, the absence of this additive at each refinery. elevated /

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energy consumption for steam generation and diesel fuel losses from water ingress into it after condensation.

The purpose of the invention is to increase the yield of the target product and simplify the process technology.

This goal is achieved by catalytic hydrogenation of the diesel fraction in the presence of an additive in the feedstock — gasoline distillate, obtained by rectifying the hydrogenate in the amount of 0.5–1.9 wt.% Per feedstock.

This amount allows to increase the yield of hydrotreated diesel fuel up to 98.0%, reduce energy costs and loss of commercial diesel fuel, and eliminate the supply of water vapor to the distillation column.

The method is carried out in an installation consisting of a reactor and a distillation column, gasoline distillate is withdrawn from the top of the column and introduced into the feed line before the hydrotreating reactor in 0.5-1.9 wt.% Calculated on the basis of raw materials The direct steam in the distillation column is discontinued, since the stripping functions are performed by gasoline distillation. The cleaning process is carried out at 360 ° C, pressure 30 atm, mass feed rate of raw material 4 h

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Example The raw material used is straight diesel fuel having the following physicochemical properties: a density of 835 kg / m; sulfur content 0.72 wt.%; fractional composition, ° C: n. 193, 10% - 235, 30% - 257, 50% - 279, 90% - 326, КК 358, yield 98%.

The process uses an alumino-molybdenum catalyst of the brand GDS, which has the following characteristics: bulk density 0.65 g / cm3; pore radius 50 A; pore volume 0.6 cm / g; surface area 240 m2 / g; granule size 1.5 mm.

Chemical composition,% mn .: nickel oxide 5.5; molybdenum oxide 18.0; cobalt oxide 0,2; silica 4.0; phosphorus oxide 3.0; sodium oxide 0.1; alumina rest.

As an additive, gasoline distillation of hydrotreating diesel fuel was used, which has the following characteristics: density 735 kg / m3; sulfur content of 0.003 wt.%; the content of dissolved hydrogen sulfide is 0.05 wt.%: the nitrogen content is 0.00043 wt.%; O.CH. by the motor method 49.3.

Fractional composition of the additive, ° С: n.k. 72, 10% - 94, 50% - 118, 90% - 179, к.к 208.

Group hydrocarbon composition of the additive, wt.%; unsaturated 1.8; naphthenic 33.2; paraffin 56.3; aromatic 8.7. The additive is the product of the same installation where the process of hydro-cleaning is carried out, which is also one of the advantages of this method. The process was carried out on a pilot installation of hydro- nizational processes,

Process conditions: temperature 360 ° C: pressure 30 atm; mass feed rate of 4 hours; supply of hydrogen-containing gas 80 l / h. Then the hydrogenate was dispersed on

distillation column to produce diesel fuel and gasoline distillate.

Table 1 presents the results of the method for producing hydrotreated diesel fuel according to the proposed method and known using as an additive the catalytic purification residue of gasolines in an amount of 15 wt.% (ASD).

How should published Table 1, the introduction

gasoline additives to 1.9 wt.% increases the yield of hydrotreated diesel fuel by 1.7 wt.% compared with the prototype. At the same time with the introduction

2.5 wt.% Of the additive. The flash point of the hydrotreated diesel fuel falls below 650 ° C, which does not correspond to GOST. Therefore, the optimum concentration of the additive is 0.5-1.9 wt.% In

based on raw materials. It should be noted that with an increase in the amount of the additive, the degree of desulfurization of the raw material increases.

PRI mme R 2. The process of Hydrotreating

diesel fuel is spent on an industrial plant with a capacity of 1.2 million tons / year in raw materials.

As the raw material, a straight diesel fraction is used, as an additive - gasoline distillation of hydrotreating of the same installation. The properties of the raw materials and additives correspond to example 1. Hydrotreating conditions are similar to example 1. The GCD-202 catalyst was used on the unit,

0 having the following characteristics: bulk density 650 kg / m3; strength index 2.2 kg / mm; specific surface area 220 m / g; volume of 0.49 cm / g; granule size: diameter 1.5 mm: length 5.0 mm; chemical composition, wt%: nickel oxide 4.2; molybdenum oxide 14.7; sodium oxide 0.2; alumina rest; the promoting additive is CoHNaY zeolite, catalyst service life is 6 years.

The results are presented in table. 2

As follows from the data of Table 2, the introduction of an additive for gasoline distillation of hydrotreating diesel fuel into raw materials in an amount of 0.5-1.9 wt.% Contributes to an increase in the yield of hydrotreated diesel fuel and a decrease in the consumption of water vapor in the stabilization column. Reducing the consumption of water vapor occurs due to the fact that gasoline performs steam functions. Loss of diesel fuel is eliminated after stopping the supply of water vapor, since there is no need to drain the water that enters the purified diesel fuel.

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Claims (1)

Invention Formula The method of producing diesel fuel by catalytic hydrogenation of the diesel fraction in the presence of an additive and subsequent distillation of hydrogenation to obtain the desired product and gasoline distillate, characterized in that, in order to increase the yield of the target product and simplify the process, use as an additive gasoline distillation obtained during the rectification hydrogenation, taken in the amount of 0.5-1.9% of the raw material. Table 1 table 2