LT3883B - Method for processing of residual oil - Google Patents

Abstract

Invention applies to the field of oil processing products, for the reduction of the viscosity of the remaining oil products. In order to increase the effectiveness of the aromatic fraction influence during visbreaking, before introducing aromatic fractions or polarising solvents into the raw material the remaining oil products are affected by cavitations. Intensity of the cavitations impact will be sufficient for the breaking apart of the asphalt associates and the remaining oil products. A selective lubricant cleaning extract or catalytic cracking gas oil is used as an aromatic fraction, 2-8 percent of the mass, and acetone is used as a polarised compound, 0.001-0.05 percentage mass of the crude product amount.

Description

The invention relates to the field of oil refining and can be used in residual petroleum products such as fuel oil, tar, asphalt and others. to reduce viscosity.

A known process for the processing of residual petroleum products using a viscous cracking process in which catalytic cracked gas oil is mixed with a portion of tar at 100-200 ° C and heated to 350-380 ° C. The tar and catalytic cracked gas oil are then mixed with the main tar tar stream supplied from the bottom of the vacuum fuel oil rectification column and containing 370-390 ° C. The catalytic cracked gas oil content is 4-5% by weight. % of total tar content. The resulting mixture is fed to a visbreaker reactor (see He <in) Tenepepa6oTKa n ηθΦτθχμμι / ιη., M: ί ^ ΗΜΜΤΘΗΘφτεχΜΜ, 1986, vol.5, c.3-6).

The disadvantage of this technique is the low efficiency of catalytic cracking gas oil influence.

A known process for the processing of residual petroleum products using 2-8 wt. % selective lubricant cleaning extract or catalytic cracker residue boiling above 420 ° C. The flow temperature after mixing of tar and aromatic fractions (selective purification extract, catalytic cracking residue) reaches 110-130 ° C (see USSR Certificate No. 1617946).

The disadvantage of this method is its low efficiency when operating a combined visbreak and fuel oil vacuum rectifier. In this case, the tar is fed into a visbreaking furnace from the bottom of a vacuum fuel oil rectification column, without intermediate heat exchange, having a temperature of 350-390 ° C. If aromatic fractions were added to the tar at this temperature, its efficiency would be reduced by approximately 1.5 times.

The closest embodiment of the present invention is a process for the treatment of residual petroleum products using visbreaking with 0.001-0.05 wt. structural states to molecular; at the onset temperature of asphaltene destruction; and at the onset temperature of asphaltene nucleation (see USSR Auth. No. 1587911).

The disadvantage of this known technique is its low efficiency in the operation of a combined visbreak and fuel oil vacuum rectification device. In this case, the tar from the bottom of the vacuum column, without intermediate heat exchange and having a temperature of 350-390 ° C, is fed to a visbreaker furnace. If acetone is introduced into the tar at this temperature, its efficiency decreases approximately twice.

The object of the invention is to increase the efficiency of the additives used in the process.

This is achieved by the fact that, before the introduction of aromatized fractions or polar solvents into the raw material, residual petroleum products are affected by cavitation, after which the additives are mixed.

The essence of the invention is that the tar, obtained during the vacuum rectification of fuel oil, is fed from the bottom of the vacuum column without intermediate heat exchange into a visbreaker furnace, previously subjected to cavitation using known equipment for this purpose. After that 2-8 masses are added to the tar. % aromatic fraction (selective lubricant cleaning extracts, catalytic cracked gas oils) or 0.001-0.05% by weight of polar compounds, preference being given to acetone. The resulting mixture is fed to a visbreaker reactor.

The cavitation effect disassembles the asphaltene associations in the tar, which are formed in the high temperature vacuum gas oil rectification column. Subsequently, the additives introduced into the tar (aromatic fractions, polar compounds) block the paramagnetic centers of the degraded asphaltenes and interfere with their secondary association. During visbreaking, asphaltenes are in a highly dispersed state, which promotes effective viscosity reduction.

The method has been tested on pilot plants.

example.

Tar containing 2.7 wt. % sulfur and a coking ratio of 17.3 wt. %, density 1,0062 t / m ³ Condensed viscosity 913.5 ° SK at 80 ° C, mixed at 6.2 ° C with 6.2 wt% selective lubricant cleaning extract (characteristics shown in Table 1) and fed to Visbreaker reactor at 450 ° C and 0.6 MPa pressure. Gases, gasoline fraction and residue boiling above 180 ° C are released from reaction products.

The fraction of visceral products isolated above 180 ° C has a relative viscosity of 31.3 ° SK at 80 ° C.

example

The tar of the first sample was mixed with 6.2% by weight of a selective lubricant cleaning extract (provided in Example 1) after cavitation and at 360 ° C. The resulting mixture is subjected to visbreaking under the same conditions as in the first example.

The fraction of viscous products isolated above the viscosity above 180 ° C has a relative viscosity of 18.2 ° SK at 80 ° C.

example

The tar of the first sample was mixed at 360 ° C with 4.7% by weight of a catalytic cracking residue boiling above 420 ° C (see Table 1 for characteristics). The resulting mixture is subjected to visbreaking under the same conditions as in the first example.

The fraction of visceral products isolated above 180 ° C has a relative viscosity of 25 ° SK at 80 ° C.

example

The tar of the first sample at 360 ° C was mixed with 4.7% by weight of a catalytic cracking residue of the same quality as in Example 3. The resulting mixture is subjected to visbreaking under the same conditions as in the first example.

The fraction of visceral products isolated above 180 ° C has a relative viscosity of 16.5 SK at 80 ° C.

example

The tar of the first sample was mixed with 5 wt.% Catalytic cracked gas oil at 360 ° C (see Table 1 for characteristics). The resulting mixture is subjected to visbreaking under the same conditions as in the first example.

The fraction of viscous products isolated above 180 ° C has a relative viscosity of 29.4 ° SK at 80 ° C.

example

The tar of the first sample was mixed with 5 wt after cavitation at 360 ° C. % catalytic cracked gas oil of the same quality as in Example 5.

The fraction of visceral products isolated above 180 ° C has a relative viscosity of 19.1 ° SK at 80 ° C.

example

Tar containing 3 wt. % fractions boiling above 500 ° C and 10% by weight. % asphaltenes with a coking index of 17.1 wt.%, density 0.9958 tn / m ³ , relative viscosity 430 ° SK at 80 ° C, mixed at 385 ° C with 0.006 wt. % acetone and feeds into visbreak at 450 ° C and 0.6 MPa. Gases, gasoline fraction and residue boiling above 180 ° C are released from reaction products.

The reaction product was isolated by the fraction boiling above 180 ° C and has a relative viscosity of 22.1 SK ⁰ to 80 ° C, the stability of 1.95.

example

The seventh sample tar after cavitation was mixed with 0.006 wt% acetone at 385 ° C. The resulting mixture is subjected to visbreaking under the same conditions as in the first example.

The fraction isolated from the visbreaking products has a relative viscosity above 180 ° C of 12.5 ° SK at 80 ° C.

The physico-chemical characteristics of the aromatized fractions are given in Table 1.

table

Indicators Catalytic cracked balance Selective ointments cleaning extract Catalytic cracked gas oil Density at 20 ° C, t / m ³ 1,0441 0.973 0.981 Viscosity at 80 ° C, ⁰ SK 2.7 3.5 1.2 Sulfur content,% w / w 2.29 2.14 0.55 Fractional composition: -boils to 500 ° C, w / w 20th 9θ - cooking start temperature, ° C - - 315 -50% boiling at temp., ° C - - 350 end temperature, ° C - - 420

The intensity of the cavitation effect which allows the effect in the 2,4,6,8 samples to be obtained is determined by the extreme change in the physico-chemical properties of the tar. In industrial conditions, the required efficiency is achieved by selecting the design of the cavitation mixer or by selecting the technological conditions prior to introduction into the cavitation mixer.

The use of the present invention will make it possible to reduce the flow rate of the distillation diluents which are incorporated into the viscous residue in the preparation of the fuel oil. The present invention can be used in industrial heavy fuel oil processing units (KT-1/1 type) as well as in any visbreaking unit.

Claims (3)

DEFINITION OF INVENTION 1. A process for the processing of residual petroleum products during visbreaking by adding aromatized fractions or polar solvents to the feedstock, characterized in that the residual petroleum products are subjected to cavitation before the addition of the aromatized fractions or polar solvents to the feedstock. 2. A process according to claim 1, wherein the aromatic fraction used is a selective lubricant cleaning extract or a catalytic cracked gas oil, 2-8% by weight of the starting material. 3. A process according to claim 1 wherein the polarized compound is acetone, 0.001-0.05 wt. % of starting feedstock.