Combination coking and hydroconversion process

• US 4,882,036 A
• Filed: 12/27/1988
• Issued: 11/21/1989
• Est. Priority Date: 09/16/1987
• Status: Expired due to Fees

• Current Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Original Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Inventors: Aldrige, Clyde L., Bearden, Roby Jr., Eidt, Clarence M. Jr.
• Primary Examiner(s): Caldarola, Glenn
• Application Number:
  US07/291,390
• Time in Patent Office: 329 Days
• Field of Search: 208/108, 208/127, 208/54, 208/55, 208/57, 208/61, 208/81, 208/85, 208/50, 210/496, 210/494.2, 210/499
• US Class Current: 208/50
• CPC Class Codes: C10B 55/00 Coking mineral oils, bitumen, tar, and the like or mixtures thereof with solid carbonaceous material cracking oils C10G
• CPC Class Codes: C10G 31/11 by dialysis
• CPC Class Codes: C10G 69/06 including at least one step of thermal cracking in the absence of hydrogen
• CPC Class Codes: C10G 9/005 Coking (in order to produce liquid products mainly)

Abstract

A hydrocarbonaceous feed, such as petroleum vacuum distillation bottoms, is upgraded by a combination coking and catalytic slurry hydroconversion process wherein a bottoms fraction from coking is passed through a microfiltration system to remove coke fines, the filtrate passed to a slurry hydroconversion zone, and the bottoms fraction from the slurry hydroconversion zone is also passed through a microfiltration system to remove catalyst particles.

Claims

1. An integrated coking and hydroconversion process which comprises the steps of:

(a) treating a hydrocarbonaceous feed having a Conradson carbon content of at least 5 weight percent in a coking zone maintained under fluidized coking conditions, including a pressure ranging from zero to about 100 psig, to produce coke and a vapor phase product, including hydrocarbonaceous comprising constituents boiling above 975°

F.;

(b) passing the vapor phase product to a scrubbing zone;

(c) separating a heavy bottoms fraction in the scrubbing zone having a Conradson carbon content of at least about 5 weight percent, including said constituents boiling above 975°

F., from said hydrocarbonaceous material;

(d) passing the heavy bottoms fraction through a microfiltration system characterized as containing a filtering means comprised of a sintered porous ceramic or metal membrane and having a substantially uniform pore size capable of retaining at least 95 percent of the solids and capable of maintaining an effective flux, thereby resulting in a solids-laden fraction and a hydrocarbonaceous filtrate;

(e) recycling at least a portion of the solidsladen fraction to the coking zone;

(f) adding a hydroconversion catalyst or hydroconversion catalyst precursor to at least a portion of said hydrocarbonaceous filtrate to form a mixture;

(g) subjecting at least a portion of said mixture of step (f) to hydroconversion conditions, in the presence of hydrogen, in a slurry hydroconversion zone to produce a hydroconverted oil;

(h) passing the hydroconverted oil to a microfiltration system substantially the same as the microfiltration system in (d), above, wherein solids suspended in the hydroconverted oil are removed; and

(i) passing the filtrate resulting from the filtration of step (h) above to a liquid-liquid separation wherein the resulting heavy fraction is recycled to the coking zone.

2. The process of claim 1 wherein the hydrocarbonaceous oil is a vacuum distillation residuum.

3. The process of claim 1 wherein the filtering means of the microfiltration systems are comprised of a sintered porous metal membrane.

4. The process of claim 3 wherein the metal is selected from iron- and nickel-based alloys.

5. The process of claim 4 wherein the iron-based alloys are stainless steels.

6. The process of claim 1 wherein the coking zone is maintained at a temperature of about 850°

F. to about 1400°

F. and a pressure from about zero to about 150 psig.

7. The process of claim 6 wherein the coking zone is maintained at a temperature from about 900°

F. to about 1200°

F. and a pressure from about 5 to about 45 psig.

8. The process of claim 1 wherein another solids-laden stream is passed through the microfiltration system along with the scrubber bottoms fraction, which other solids-laden stream is selected from the group consisting of catalytic cracker bottoms, hydroconversion bottoms, and oil sludges.

9. The process of claim 1 wherein the substantially solids-free filtrate is hydrotreated at a temperature from about 600°

F. to 800°

F., a pressure from about 400 to 10,000 psi and a hydrogen treat rate from about 500 to about 10,000 standard cubic feet per barrel of feed.

10. The process of claim 9 wherein the filtering means of the microfiltration system is comprised of a sintered porous metal membrane whose metal is selected from the group consisting of iron-and nickel-based alloys chemically and physically resistant to scrubber bottoms fraction.

11. The process of claim 1 wherein the flux is at least about 0.1 gpm/ft².

12. The process of claim 1 wherein the hydroconversion conditions include pressures ranging from about 100 to about 5,000 psig and a temperature ranging from about 650°

F. to about 1000°

F.

13. The process of claim 12 wherein the hydroconversion conditions include a pressure ranging from about 300 to about 2000 psig and a temperature ranging from about 800°

F. to about 900°

F.

14. The process of claim 1 wherein the hydrocarbonaceous feed of said coking zone has a Conradson carbon content of at least 7 weight percent.

15. The process of claim 1 wherein the heavy bottoms fraction has a Conradson carbon content of at least about 7 weight percent.

16. The process of claim 1 wherein the hydroconversion catalyst precursor is an oil-soluble metal compound or a thermally decomposable metal compound.

17. The process of claim 1 wherein the heavy bottoms fraction of step (b) comprises at least about 10 weight percent materials boiling above 975°

F.

18. The process of claim 1 wherein at least 10 weight percent of the 975+°

F. materials of said portion of heavy bottoms fraction are converted to lower boiling products.

19. The process of claim 1 wherein a portion of the hydrocarbonaceous feed is passed directly to the slurry hydroconversion zone.