Process for separating pitch from slurry hydrocracked vacuum gas oil

• US 8,540,870 B2
• Filed: 06/25/2009
• Issued: 09/24/2013
• Est. Priority Date: 06/25/2009
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: McGehee, James F., Myers, David N., Van Wees, Mark, Zimmerman, Paul R., Kleinworth, Ruth Buskus
• Primary Examiner(s): Boyer, Randy
• Application Number:
  US12/491,439
• Publication Number:
  US 20100326887A1
• Time in Patent Office: 1,552 Days
• Field of Search: 208/39, 208/41, 208/108
• US Class Current: 208/41
• CPC Class Codes: C10G 47/00 Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions C10G15/00 takes precedence; destructive hydrogenation of non-melting solid carbonaceous or similar materials C10G1/06

Abstract

A process is disclosed for converting heavy hydrocarbon feed into lighter hydrocarbon products. The heavy hydrocarbon feed is slurried with a particulate solid material to form a heavy hydrocarbon slurry and hydrocracked in a slurry hydrocracking unit to produce vacuum gas oil (VGO) and pitch. A first vacuum column separates VGO from pitch, and a second vacuum column further separates VGO from pitch. As much as 15 wt-% of VGO can be recovered by the second vacuum column and recycled to the slurry hydrocracking unit. A pitch composition is obtained which can be made into particles and transported without sticking together.

Claims

1. A process for converting heavy hydrocarbon feed into lighter hydrocarbon products comprising:

hydrocracking said heavy hydrocarbon feed slurried with a particulate solid material in the presence of hydrogen in a hydrocracking reactor to produce a hydrocracked stream including vacuum gas oil (VGO) and pitch;

separating at least a portion of said hydrocracked stream in a first vacuum column to provide a first pitch stream and a first VGO stream; and

separating at least a portion of said first pitch stream in a second vacuum column to provide a second pitch stream and a second VGO stream; and

recycling the second VGO stream to the hydrocracking step.

2. The process of claim 1 wherein the entry pressure in the first vacuum column is greater than the entry pressure in the second vacuum column.

3. The process of claim 1 further comprising forming pitch in said second pitch stream into non-sticking solid particles at temperatures up to 66°

C. (150°

F).

4. The process of claim 1 wherein a slop wax stream taken below an HVGO cut is recycled back to the hydrocracking reactor.

5. The process of claim 1 wherein the pitch from the second vacuum column has a concentration of VGO boiling below about 538°

C. (1000°

F.) of less than 14 wt-%.

6. The process of claim 1 wherein the pitch from the second vacuum column has an onset of softening point temperature of at least 66°

C. (150°

F.).

7. The process of claim 1 further comprising recycling a portion of said first pitch stream to the hydrocracking step.

8. The process of claim 1 further comprising heating the portion of the hydrocracked stream to a temperature at or below about 370°

C. and feeding said portion of the hydrocracked stream to the first vacuum column.

9. The process of claim 1 wherein said second vacuum column is a film generating evaporator.

10. A process for converting heavy hydrocarbon feed into lighter hydrocarbon products comprising:

hydrocracking said heavy hydrocarbon feed slurried with a particulate solid material in the presence of hydrogen in a hydrocracking reactor to produce a hydrocracked stream including vacuum gas oil (VGO) and pitch;

separating at least a portion of said hydrocracked stream in a first vacuum column to provide a first pitch stream and a first VGO stream;

separating at least a portion of said first pitch stream in a second vacuum column to provide a second pitch stream and a second VGO stream; and

forming pitch in said second pitch stream into non-sticky solid particles at temperatures up to 66°

C. (150°

F.).

11. The process of claim 10 wherein the entry pressure in the first vacuum column is greater than the entry pressure in the second vacuum column.

12. The process of claim 10 wherein said forming step comprises emitting pitch through openings in a perforated wall to form particles, cooling said particles on a conveyor belt and collecting said particles.

13. The process of claim 10 wherein said forming step includes indirect cooling said solid particles with cooling media.

14. The process of claim 10 wherein the pitch from the second vacuum column has an onset of softening point temperature of at least 66°

C. (150°

F.).

15. The process of claim 10 further comprising recycling at least a portion of said first pitch stream to the hydrocracking step.

16. The process of claim 10 further comprising recycling the second VGO stream to the hydrocracking step.

17. The process of claim 16 further comprising emitting pitch through openings in a perforated wall to form particles, cooling said particles on a conveyor belt by indirect heat exchange, collecting said particles from said conveyor belt and transporting said particles without further indirect heat exchange.

18. The process of claim 10 wherein said second vacuum column is a film generating evaporator.

19. A process for converting heavy hydrocarbon feed into lighter hydrocarbon products comprising:

hydrocracking said heavy hydrocarbon feed slurried with a particulate solid material in the presence of hydrogen in a hydrocracking reactor to produce a hydrocracked stream including vacuum gas oil (VGO) and pitch;

separating at least a portion of said hydrocracked stream in a first vacuum column to provide a first pitch stream and a first VGO stream; and

separating at least a portion of said first pitch stream in a second vacuum column to provide a second pitch stream and a second VGO stream;

wherein a slop wax stream taken below an HVGO cut is recycled back to the hydrocracking reactor.

20. The process of claim 19 further comprising heating the portion of the hydrocracked stream to a temperature at or below about 370°

C. and feeding said portion of the hydrocracked stream to the first vacuum column.