Integrated process for upgrading heavy oil

Patent metadata

Field	Value
Publication number	US-9290706-B2
Application number	US-201313851802-A
Country	US
Kind code	B2
Filing date	Mar 27, 2013
Priority date	May 31, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

The invention provides an integrated process for processing heavy oil, wherein the integrated process at least comprises: solvent deasphalting is carried out for heavy oil material, and de-oiled asphalt phase is mixed with dispersing agent and then entered a thermal cracking reactor to undergo thermal cracking reactions. Upgraded oil can be obtained through the mixture of the de-asphalted oil and thermal cracking oil separated from thermal cracking reaction products. The solvent and heavy gas oil, which are separated from the thermal cracking reaction products, are respectively recycled back to the solvent deasphalting process as solvent and as mixed feed to remove asphaltene. The integrated process of the present invention solves the problems that solvent is difficult to be separated from asphalt with high softening point in solvent deasphalting process and hard asphalt is difficult to be transported.

First claim

What is claimed is:

1. A integrated process for processing heavy oil, comprising at least the following processes, wherein:
a heavy oil feedstock, which substantially does not comprise <350° C. atmospheric distillates, is used as feed and subjected to solvent deasphalting process in an extraction tower with an extraction solvent, a de-asphalted oil and a de-oiled asphalt phase including the extraction solvent are collected;
the de-oiled asphalt phase including the extraction solvent is mixed with a dispersing solvent and then enters into a thermal cracking reactor to be subjected to a thermal cracking process, so as to obtain thermal cracking reaction product and coke, the thermal cracking reaction product is led out, gas, solvent, thermal cracking oil and 450° C.+ heavy gas oil are separated therefrom;
the solvent separated from the thermal cracking product is recycled back to the solvent deasphalting process to be recycled, the 450° C.+ heavy gas oil is recycled back to the solvent deasphalting process to be used as mixed feed;
upgraded oil is obtained through mixing the de-asphalted oil and the thermal cracking oil separated from the thermal cracking reaction product.

2. The integrated process for processing the heavy oil according to claim 1 , further including:
pre-fractionating a heavy oil feedstock including <350° C. atmospheric distillates; collecting distilled oil; products from the bottom of a distillation tower being taken as the feed for the solvent deasphalting process; wherein the cut point temperature of the prefractionation is 350-565° C., and the distilled oil is taken as light oil to be processed, or mixed with the de-asphalted oil and the thermal cracking oil to form upgraded oil.

3. The integrated process for processing the heavy oil according to claim 2 , wherein during the solvent deasphalting process, a first extraction solvent is mixed with the feed and entered into the extraction tower; separating the de-asphalted oil and the asphalt phase; a second extraction solvent is added to the bottom of the extraction tower to further extract the asphalt phase, so as to separate the de-asphalted oil; the de-asphalted oil is discharged from the top of the extraction tower; obtained de-oiled asphalt phase including the extraction solvent is discharged from the bottom of the extraction tower and subjected to thermal cracking process after being mixed with the dispersing solvent; the first extraction solvent, the second extraction solvent and the dispersing solvent are selected from C3-C6 alkane or mixed fractions thereof; total mass flow ratio of the three solvents to the feed of the extraction tower is 3-8:1, wherein solvent distribution proportion is: the first extraction solvent: the second extraction solvent: the dispersing solvent is (0.75-0.93) : (0-0.15) : (0.02-0.10) .

4. The integrated process for processing the heavy oil according to claim 3 , wherein the temperature of the extraction tower is 80-250° C. and the pressure is 3.5-10 MPa.

5. The integrated process for processing the heavy oil according to claim 2 , wherein the thermal cracking reaction product is firstly absorbed by the substances from the bottom of the tower after prefractionation and cut-fraction; the 450° C.+ heavy gas oil is separated, and the gas, the solvent and the thermal cracking oil are further distilled and separated from the remaining thermal cracking reaction product.

6. The integrated process for processing the heavy oil according to claim 1 , further including:
subjecting the upgraded oil to fixed-bed hydrotreating process to obtain a hydrotreating upgraded oil.

7. The integrated process for processing the heavy oil according to claim 6 , wherein during the process that the upgraded oil becomes hydrotreating upgraded oil after undergoing fixed bed hydrotreating, in the hydrotreating process, the temperature is 360-450° C., the pressure is 6-20 MPa, the hydrogen-oil volume ratio is 200-1200:1, and space velocity of the reactor is 0.3-3.0 h −1 .

8. The integrated process for processing the heavy oil according to claim 1 , wherein during the solvent deasphalting process, a first extraction solvent is mixed with the feed and entered into the extraction tower; separating the de-asphalted oil and the asphalt phase; a second extraction solvent is added from the bottom of the extraction tower to further extract the asphalt phase, so as to separate the de-asphalted oil; the de-asphalted oil is discharged from the top of the extraction tower; obtained de-oiled asphalt phase including the extraction solvent is discharged from the bottom of the extraction tower and subjected to thermal cracking process after being mixed with the dispersing solvent; the first extraction solvent, the second extraction solvent and the dispersing solvent are selected from C3-C6 alkane or mixtures thereof; total mass flow ratio of the three solvents to the feed of the extraction tower is 3-8:1, wherein solvent distribution proportion is: the first extraction solvent: the second extraction solvent: the dispersing solvent is (0.75-0.93) : (0-0.15) : (0.02-0.10) .

9. The integrated process for processing the heavy oil according to claim 8 , wherein the temperature of the extraction tower is 80-250° C. and the pressure is 3.5-10 MPa.

10. The integrated process for processing the heavy oil according to claim 8 , wherein the distribution proportion of the three solvents is: the first extraction solvent : the second extraction solvent : the dispersing solvent=(0.75-0.93) : (0.05-0.15) : (0.02-0.10) .

11. The integrated process for processing the heavy oil according to claim 10 , wherein the temperature of the high-temperature hydrocarbon vapor and the high-temperature steam is 500-600° C., the high-temperature coke particles which are partially burned, or inorganic particles loaded with burned coke is coke discharged from the thermal cracking reaction, coke attached to the inorganic particles or heat providing media which are recycled back to the thermal cracking reactor after being partially burned at a temperature up to 600-750° C.

12. The integrated process for processing the heavy oil according to claim 11 , wherein the average temperature of the thermal cracking reaction is 450-550° C.

13. The integrated process for processing the heavy oil according to claim 1 , wherein the de-asphalted oil separated from the solvent deasphalting process undergoes supercritical separation and / or steam stripping to recover the extraction solvent in the de-asphalted oil, in the supercritical separation, solvent density is controlled in the rage of 0.15-0.20 g/cm 3 .

14. The integrated process for processing the heavy oil according to claim 1 , wherein the de-oiled asphalt including the extraction solvent is dispersed into the thermal cracking reactor by injection and contact with high-temperature heat providing media to undergo thermal reactions and obtain thermal cracking reaction products, the high-temperature heat providing media include high-temperature oil gas, high-temperature steam, high-temperature coke particles which are partially burned, or inorganic particles loaded with burned coke.

15. The integrated process for processing the heavy oil according to claim 14 , wherein the average temperature of the thermal cracking reaction is 450-550° C.

16. The integrated process for processing the heavy oil according to claim 15 , wherein the average temperature of the thermal cracking reaction is 470-530° C.

17. The integrated process for processing the heavy oil according to claim 14 , wherein the thermal cracking reaction product is first

Assignees

• Univ China Petroleum

Inventors

• Zhao Suoqi
• Sun Xuewen
• Xu Zhiming
• Xu Chunming
• Chung Keng H

Classifications

• C10G2300/4081

  Recycling aspects · CPC title

• C10G69/06

  including at least one step of thermal cracking in the absence of hydrogen · CPC title

• C10G55/04 Primary

  including at least one thermal cracking step · CPC title

• C10G21/003

  Solvent de-asphalting · CPC title

• C10G2300/44

  Solvents · CPC title