Separation of sulfurous materials

Patent metadata

Field	Value
Publication number	US-11447710-B2
Application number	US-201916404376-A
Country	US
Kind code	B2
Filing date	May 6, 2019
Priority date	May 7, 2018
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

Abstract

The present disclosure relates to systems and methods for separation of sulfurous material(s) from a multi-component feed stream. The systems and methods can comprise contacting the multi-component feed stream with a solvent in a contacting column so that at least a portion of the sulfurous material(s) is transferred from the multi-component feed stream to the solvent. A stream of a substantially purified gas can thus be provided along with a liquid stream comprising at least a majority of the sulfurous material. In particular, the solvent can comprise liquid carbon dioxide, which can be particularly beneficial for removing sulfurous materials from multi-component feed streams.

First claim

The invention claimed is:

1. A method for separating a sulfurous material from a multi-component feed stream, the method comprising:
processing a multi-component feed stream in a contacting column with liquid carbon dioxide so that the multi-component feed stream is contacted with the liquid carbon dioxide, the multi-component feed stream comprising one or more fuel gas components including at least one hydrocarbon, and the multi-component feed stream further comprising a sulfurous material including at least hydrogen sulfide;
withdrawing from the contacting column a bottom product stream containing at least a portion of the sulfurous material including at least hydrogen sulfide from the multi-component feed stream; and
withdrawing from the contacting column an overhead vapor stream containing at least a portion of the one or more fuel gas components including at least one hydrocarbon.

2. The method of claim 1 , wherein the contacting column is a distillation column.

3. The method of claim 1 , wherein the contacting column is a counter-current contacting column.

4. The method of claim 1 , wherein prior to said processing of the multi-component feed stream, the multi-component feed stream comprises carbon dioxide in an amount of at least 2% on a molar basis.

5. The method of claim 1 , wherein the sulfurous material in the multi-component feed stream further comprises one or more of carbonyl sulfide, thiol-containing compounds, carbon disulfide, disulfide bond-containing compounds.

6. The method of claim 1 , wherein the multi-component feed stream is at a temperature of about −10° C. to about −55° C.

7. The method of claim 1 , wherein the liquid carbon dioxide is at a temperature of about −10° C. to about −55° C.

8. The method of claim 1 , wherein the contacting column is operated under conditions such that substantially no portion of any carbon dioxide in the contacting column is solidified during passage through the contacting column.

9. The method of claim 1 , wherein the liquid carbon dioxide is at a pressure of about 7 bar to about 60 bar.

10. The method of claim 1 , wherein the method further comprises passing at least a portion of the overhead vapor stream containing at least a portion of the fuel gas that is withdrawn from the contacting column through one or more heat exchangers so that the overhead vapor stream containing at least a portion of the fuel gas is heated and one or more further streams are cooled.

11. The method of claim 10 , wherein the method further comprises evaporating one or more streams of a liquid refrigerant in the one or more heat exchangers to maintain a heat balance thereof.

12. The method of claim 11 , wherein the one or more streams of the liquid refrigerant comprises liquid carbon dioxide.

13. The method of claim 1 , wherein the overhead vapor stream withdrawn from the contacting column comprises less than 2% molar of the sulfurous material.

14. The method of claim 13 , wherein the overhead vapor stream withdrawn from the contacting column comprises less than 2 ppm molar of the sulfurous material.

15. The method of claim 1 , wherein the contacting column is operated at a pressure of about 7 bar to about 60 bar.

16. The method of claim 1 , wherein the contacting column is configured for heat removal at one or more stages present in the contacting column at a position that is higher in the contacting column than a position for injecting of the multi-component feed stream.

17. The method of claim 1 , wherein the contacting column comprises a re-boiler.

18. The method of claim 17 , wherein at least a portion of the multi-component feed stream is passed through the re-boiler prior to injecting into the contacting column.

19. The method of claim 1 , further comprising passing the overhead vapor stream through a separation unit configured for removal of at least a portion of any carbon dioxide present in the overhead vapor stream.

20. The method of claim 19 , wherein the separation unit is a membrane separator configured for separating the overhead vapor stream into a product fuel gas stream and a permeate stream comprising at least carbon dioxide.

21. The method of claim 20 , wherein the product fuel gas stream contains less than 2 ppm molar of the sulfurous material.

22. The method of claim 20 , wherein the product fuel gas stream contains less than 2% molar of carbon dioxide.

23. The method of claim 20 , further comprising recycling at least a portion of the carbon dioxide from the permeate stream for use in the contacting column.

24. The method of claim 1 , further comprising passing the bottom product stream through one or more distillation columns configured for separating out one or more further components present in the bottom product stream in addition to the sulfurous material.

25. The method of claim 1 , wherein the multi-component feed stream is sour natural gas.

26. The method of claim 25 , wherein the bottom product stream contains at least a portion of any hydrogen sulfide and C 2 to C 5 hydrocarbons present in the sour natural gas.

27. The method of claim 25 , wherein the overhead vapor stream contains a majority of methane present in the sour natural gas.

28. The method of claim 1 , wherein at least a portion of the fuel gas in the overhead vapor stream is provided into a combustor of a power production unit.

29. A method for separating a multi-component feed stream, the method comprising:
providing a multi-component feed stream at a temperature of about −10° C. to about −55° C., the multi-component feed stream comprising one or more fuel gas components including at least one hydrocarbon, and the multi-component feed stream further comprising a sulfurous material including at least hydrogen sulfide;
providing carbon dioxide at a temperature of about −10° C. to about −55° C. and a pressure of about 7 bar to about 60 bar, wherein greater than 90% molar of the carbon dioxide is in a liquid form;
processing the multi-component feed stream and the carbon dioxide in a contacting column;
withdrawing from the contacting column a bottom product stream containing at least a portion of the sulfurous material including at least hydrogen sulfide from the multi-component feed stream; and
withdrawing from the contacting column an overhead vapor stream containing at least a portion of the one or more fuel gas components including at least one hydrocarbon.

30. The method of claim 1 , wherein:
the multi-component feed stream including at least a sulfurous material and a fuel gas is a multi-component feed stream including at least sulfurous compounds and ethane;
the contacting column is a distillation column; and
the overhead vapor stream containing at least a portion of the fuel gas comprises ethane and carbon dioxide.

31. The method of claim 30 , wherein the distillation column is operated at a pressure of about 20 bar to about 50 bar.

32. The method of claim 31 , wherein the distillation column includes an overhead condenser and a reboiler.

33. The method of claim 24 , wherein the one or more distillation columns includes a de-ethanizer unit configured to process the bottom product stream to provide a stream comprising ethane and a stream comprising C3 and greater hydrocarbons, optionally wherein the stream comprising eth

Assignees

• 8 Rivers Capital Llc

Inventors

• Allam Rodney John
• Rafati Mohammad

Classifications

• Y02C20/40

  of CO2 · CPC title

• B01D2257/504

  Carbon dioxide · CPC title

• C10L2290/545

  Washing, scrubbing, stripping, scavenging for separating fractions, components or impurities during preparation or upgrading of a fuel · CPC title

• B01D2256/245

  Methane · CPC title

• C10L3/103 Primary

  Sulfur containing contaminants · CPC title