Upgrading of Hydrocarbons by Hydrothermal Process

• US 20120061291A1
• Filed: 09/14/2010
• Published: 03/15/2012
• Est. Priority Date: 09/14/2010
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Choi, Ki-Hyouk, Punetha, Ashok K., Al-Dossary, Mohammed R., Aljishi, Mohammad F.
• Granted Patent: US 9,039,889 B2
• Time in Patent Office: Days
• US Class Current: 208/53
• CPC Class Codes: C10G 2300/42 Hydrogen of special source or of special composition
• CPC Class Codes: C10G 2300/805 Water
• CPC Class Codes: C10G 47/32 in the presence of hydrogen-generating compounds
• CPC Class Codes: C10G 49/18 in the presence of hydrogen-generating compounds, e.g. ammonia, water, hydrogen sulfide
• CPC Class Codes: C10G 49/22 Separation of effluents
• CPC Class Codes: C10G 65/02 plural serial stages only
• CPC Class Codes: C10G 65/10 including only cracking steps

Abstract

A hydrocarbon feedstock upgrading method is provided. The method includes supplying the hydrocarbon feedstock, water and a pre-heated hydrogen donating composition to a hydrothermal reactor where the mixed stream is maintained at a temperature and pressure greater than the critical temperatures and pressure of water in the absence of catalyst for a residence time sufficient to convert the mixed stream into a modified stream. The hydrogen donating composition is pre-heated and maintained at a temperature of greater than about 50° C. for a period of at least about 10 minutes. The modified stream includes upgraded hydrocarbons relative to the hydrocarbon feedstock. The modified stream is then separated into a gas stream and a liquid stream and the liquid stream is separated into a water stream and an upgraded hydrocarbon product stream.

Claims

1. A method of upgrading a hydrocarbon feedstock, the method comprising the steps of:

supplying a mixed stream comprising the hydrocarbon feedstock, water and a pre-heated hydrogen donating composition to a hydrothermal reactor, wherein the mixed stream is maintained at a pressure greater than the critical pressure of water and a temperature greater than the critical temperature of water, and wherein the pre-heated hydrogen donating composition is pre-heated to a temperature of greater than about 50°

C. and maintained at said temperature for a period of at least about 10 minutes;

reacting the mixed stream in the hydrothermal reactor in the absence of catalyst;

reacting the mixed stream in the hydrothermal reactor for a residence time sufficient to convert the mixed stream into a modified stream, said modified stream comprising upgraded hydrocarbons relative to the hydrocarbon feedstock;

separating the modified stream into a gas stream and a liquid stream; and

separating the liquid stream into a water stream and an upgraded hydrocarbon product stream.

2. The method of claim 1, wherein the hydrogen donating composition is a bottoms streams from a process selected from the group consisting of hydrocracking, coking, visbreaking, hydrotreating, or catalytic cracking.

3. The method of claim 1, wherein the hydrogen donating composition is produced by the following steps:

supplying a low grade hydrocarbon feedstock to a reactor, the reactor being selected from the group consisting of a hydrocracker, a coker, a visbreaker, a hydrotreater, or a catalytic cracker, wherein said low grade hydrocarbon feedstock is converted to intermediate stream;

separating the intermediate stream into a hydrocarbon stream comprising upgraded hydrocarbons and a bottoms stream comprising the hydrogen donating composition.

4. The method of claim 1, wherein the method does not include the step of supplying hydrogen gas to the hydrothermal reactor.

5. The method of claim 1, further comprising, prior to the step of separating the modified stream:

depressurizing the modified stream; and

reducing the temperature of the modified stream.

6. The method of claim 1, further comprising:

maintaining the hydrothermal reactor pressure at greater than about 24 MPa; and

maintaining the hydrothermal reactor temperature at greater than about 395°

C.

7. The method of claim 1, further comprising:

maintaining the hydrothermal reactor pressure at between about 24 and 26 MPa; and

maintaining the hydrothermal reactor temperature at between about 400°

C. and 450°

C.

8. The method of claim 1, wherein the volumetric ratio of the hydrocarbon feedstock to water supplied to the hydrothermal reactor is between 1:

10 and 10;

1.

9. The method of claim 1, wherein the weight ratio of the hydrogen donating composition to the hydrocarbon feedstock is between about 0.005:

1 and 0.1;

1.

10. The method of claim 1, prior to mixing the hydrocarbon feedstock, hydrogen donating composition and water, further comprising the steps of:

preheating the hydrocarbon feedstock to a temperature of up to about 250°

C.;

preheating the hydrogen donating composition to a temperature of up to about 500°

C.;

preheating the water to a temperature of up to about 650°

C.; and

mixing the preheated hydrocarbon feedstock stream, the hydrogen donating composition, and the water stream to produce the mixed stream.

11. The method of claim 1, wherein the residence time of the mixed stream in the hydrothermal reactor is between about 1 minute and 30 minutes.

12. The method of claim 1, wherein the hydrogen donating composition is selected from the group consisting of tetralin, alkylated tetralin, extracts of liquefied coal, petroleum refinery distillates, cracked products from a petroleum refinery product stream, residue from a petroleum refinery, and combinations of the same.

13. The method of claim 1, wherein the hydrogen donating composition is preheated to a temperature of between about 120°

C. and 350°

C., and wherein said hydrogen donating composition is maintained at said preheated temperature for a period of between about 10 and 90 minutes.

21. The method of claim 1, wherein the residence time of the mixed stream in the main hydrothermal reactor is between 1 minute and 30 minutes.

14. A method for upgrading a hydrocarbon feedstock, the method comprising the steps of

supplying a low grade first hydrocarbon feedstock to a first reactor selected from the group consisting of a hydrocracker, a coker, a visbreaker, a hydrotreater, and a catalytic cracker, wherein said first reactor configured for the upgrading of the first hydrocarbon feedstock;

recovering an intermediate hydrocarbon stream from the first reactor;

separating the intermediate hydrocarbon stream into a light hydrocarbon stream and a bottoms stream;

pre-heating the bottoms stream to a temperature of at least about 120°

C. for a period of at least about 10 minutes;

mixing said pre-heated bottoms stream, a hydrocarbon feedstock, and water to form a reaction mixture;

supplying the reaction mixture to a main hydrothermal reactor maintained at a temperature greater than about 374°

C. and a pressure greater than about 22.06 MPa for a residence time in the hydrothermal reactor of between about 30 seconds and 60 minutes to produce modified stream comprising upgraded hydrocarbons, wherein the main hydrothermal reactor does not include a catalyst;

withdrawing the modified stream;

separating the modified stream into a gaseous phase and a liquid phase; and

separating the liquid phase into a water stream and an upgraded hydrocarbon stream, wherein the upgraded hydrocarbon stream has at least one improved physical property as compared with the hydrocarbon feedstock, the physical properties selected from sulfur content, nitrogen content, metal content, coke content, and API gravity.

15. The method of claim 14, wherein the method does not include supplying hydrogen gas to the main hydrothermal reactor.

16. The method of claim 14, further comprising, prior to the step of separating the modified stream:

depressurizing the modified stream; and

reducing the temperature of the modified stream.

17. The method of claim 14, further comprising:

maintaining the pressure in the main hydrothermal reactor at between about 24 MPa and about 26 MPa; and

maintaining the temperature in the main hydrothermal reactor at greater than about 380°

C. and about 550°

C.

18. The method of claim 14, wherein the volumetric ratio of the hydrocarbon feedstock to water supplied to the hydrothermal reactor is between 1:

10 and 10;

1.

19. The method of claim 14, wherein the weight ratio of the hydrogen donating composition to the hydrocarbon feedstock is between about 0.005:

1 and 0.1;

1.

20. The method of claim 14, further comprising the steps of:

preheating a hydrocarbon feedstock stream to a temperature of up to about 250°

C.;

preheating a hydrogen donating composition to a temperature of up to about 500°

C.;

preheating a water stream to a temperature of up to about 650°

C.; and

mixing the preheated hydrocarbon feedstock stream, the hydrogen donating composition, and the water stream to produce the mixed stream.