Process for removing heavy polynuclear aromatic compounds from a hydroprocessed stream

• US 8,574,425 B2
• Filed: 12/14/2010
• Issued: 11/05/2013
• Est. Priority Date: 12/14/2010
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Hoehn, Richard K., Breitenfeldt, Daniel J.
• Primary Examiner(s): Boyer, Randy
• Assistant Examiner(s): VALENCIA, JUAN C
• Application Number:
  US12/967,773
• Publication Number:
  US 20120145594A1
• Time in Patent Office: 1,057 Days
• Field of Search: 208/100, 282/82, 196/111
• US Class Current: 208/82
• CPC Class Codes: B01D 3/141 where at least one distillation column contains at least one dividing wall
• CPC Class Codes: C10G 2300/1096 Aromatics or polyaromatics
• CPC Class Codes: C10G 2300/206 Asphaltenes
• CPC Class Codes: C10G 2400/30 Aromatics
• CPC Class Codes: C10G 67/00 Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only
• CPC Class Codes: C10G 7/00 Distillation of hydrocarbon oils

Abstract

The present invention is an improved process for stripping HPNA'"'"'s from hydroprocessed streams in a fractionation column having a split shell configuration. Only one vapor stripping feed is required to the split shell of the fractionation column. The resulting reduction in steam requirement provides a superior fractionation in the column.

Claims

1. A process for removing HPNA'"'"'s from a hydroprocessed stream comprising:

feeding the hydroprocessed stream comprising HPNA'"'"'s to a second compartment in a fractionation column also having a first compartment;

feeding a stripping vapor to the second compartment to strip lighter hydrocarbons from the hydroprocessed stream and provide a stripped hydroprocessed stream and an enriched stripping vapor;

withdrawing the stripped hydroprocessed stream from the second compartment with a greater concentration of HPNA'"'"'s than in the hydroprocessed stream fed to the second compartment;

withdrawing the enriched stripping vapor enriched with lighter hydrocarbons from the second compartment; and

passing the enriched stripping vapor exiting downwardly from the second compartment to the first compartment in the fractionation column.

2. The process of claim 1 further comprising feeding a first hydroprocessed stream to the fractionation column and the hydroprocessed stream of claim 1 is a second hydroprocessed stream.

3. The process of claim 2 wherein the first hydroprocessed stream is lighter than the second hydroprocessed stream.

4. The process of claim 2 further comprising fractionating the first hydroprocessed stream in the fractionation column and stripping lighter materials from heavier portions of the first hydroprocessed stream in the first compartment with enriched stripping vapor from the second compartment.

5. The process of claim 4 further comprising taking a stripped first hydroprocessed stream from the first compartment as the second hydroprocessed feed.

6. The process of claim 1 further comprising directing the vapor exiting from the second compartment downwardly to a lower end of the first compartment.

16. The process of claim 1 wherein the stripping vapor comprises steam.

17. The process of claim 1 further comprising providing a baffle occluding communication between the second compartment and a volume of the fractionation column above the baffle.

18. The process of claim 1 wherein the second compartment has a closed lower end distinct from the fractionation column.

7. A process for fractionating a hydroprocessed stream comprising:

feeding a first hydroprocessed stream to a fractionation column;

stripping heavier portions of the first hydroprocessed stream in a first compartment of the fractionation column;

feeding a second hydroprocessed stream to a second compartment of the fractionation column;

feeding a stripping vapor to the second compartment to strip the second hydroprocessed stream of lighter hydrocarbons to provide a stripped hydroprocessed stream and an enriched stripping vapor stream;

withdrawing the stripped hydroprocessed stream from the second compartment with a greater concentration of HPNA'"'"'s than in the second hydroprocessed stream fed to the second compartment;

withdrawing the enriched stripping vapor enriched with lighter hydrocarbons from the second compartment; and

passing the enriched stripping vapor exiting downwardly from the second compartment to the first compartment for stripping lighter materials from heavier portions of the first hydroprocessed stream.

8. The process of claim 7 wherein the first hydroprocessed stream is lighter than the second hydroprocessed stream.

9. The process of claim 7 further comprising taking a stripped first hydroprocessed stream from the first compartment as the second hydroprocessed feed.

10. The process of claim 7 further comprising directing vapor exiting from the second compartment downwardly.

19. The process of claim 7 wherein the stripping vapor comprises steam.

11. A process for hydroprocessing a hydrocarbon stream comprising:

contacting a hydrocarbon stream with hydrogen and hydroprocessing catalyst under hydroprocessing conditions to provide a hydroprocessed effluent;

separating the hydroprocessed effluent to provide a first hydroprocessed stream;

feeding the first hydroprocessed stream to a fractionation column having a first compartment and a second compartment;

feeding a second hydroprocessed stream comprising HPNA'"'"'s to the second compartment;

feeding a stripping vapor to the second compartment to strip lighter hydrocarbons from the second hydroprocessed stream and provide a stripped hydroprocessed stream and an enriched stripping vapor;

withdrawing the stripped hydroprocessed stream from the second compartment with a greater concentration of HPNA'"'"'s than in the hydroprocessed stream fed to the second compartment;

withdrawing the enriched stripping vapor enriched with lighter hydrocarbons from the second compartment; and

passing the enriched stripping vapor exiting downwardly from the second compartment to a first compartment in the fractionation column.

12. The process of claim 11 further comprising separating the hydroprocessed effluent into a vapor stream that provides the first hydroprocessed stream and a liquid stream that provides the second hydroprocessed stream.

13. The process of claim 11 further comprising fractionating the first hydroprocessed stream in the fractionation column and stripping lighter materials from heavier portions of the first hydroprocessed stream in the first compartment with enriched stripping vapor from the second compartment.

14. The process of claim 13 further comprising taking stripped heavier portions of the first hydroprocessed stream from the first compartment as the second hydroprocessed feed.

15. The process of claim 11 further comprising directing the vapor exiting from the second compartment downwardly to a lower end of the first compartment.

20. The process of claim 11 wherein the stripping vapor comprises steam.