Fischer-Tropsch Based Gas to Liquids Systems and Methods

• US 20150322350A1
• Filed: 05/08/2015
• Published: 11/12/2015
• Est. Priority Date: 05/09/2014
• Status: Abandoned Application

• Current Assignee: Siluria Technologies, Inc. (Lummus Technology LLC)
• Original Assignee: Siluria Technologies, Inc. (Lummus Technology LLC)
• Inventors: Iyer, Rahul, Patel, Bipinkumar, Scher, Erik
• Application Number:
  US14/707,466
• Publication Number:
  US 20150322350A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 3/143 by two or more of a fractionation, separation or rectification step
• CPC Class Codes: C01B 2203/0216 containing a non-catalytic steam reforming step
• CPC Class Codes: C01B 2203/0233 the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/0244 the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/043 Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• CPC Class Codes: C01B 2203/0445 Selective methanation
• CPC Class Codes: C01B 2203/061 Methanol production
• CPC Class Codes: C01B 2203/062 Hydrocarbon production, e.g. Fischer-Tropsch process
• CPC Class Codes: C01B 2203/1241 Natural gas or methane
• CPC Class Codes: C01B 2203/148 involving a recycle stream to the feed of the process for making hydrogen or synthesis gas
• CPC Class Codes: C01B 3/34 by reaction of hydrocarbons with gasifying agents
• CPC Class Codes: C01B 3/386 Catalytic partial combustion
• CPC Class Codes: C10G 2/32 with the use of catalysts
• CPC Class Codes: C10G 2/34 Apparatus, reactors

Abstract

A method for generating hydrocarbon compounds containing at least two carbon atoms (C₂₊ compounds) comprises directing a natural gas feed stream from a non-Fischer Tropsch process and comprising methane and C₂₊ compounds to at least one separation unit to separate the methane from the C₂₊ compounds. The separated C₂₊ compounds are directed to a fractionation unit to separate the separated C₂₊ compounds into individual streams. The separated methane is directed to a synthesis gas (syngas) unit to partially oxidize the methane to hydrogen (H₂) and carbon monoxide (CO), which are subsequently directed to a Fischer-Tropsch unit comprising a Fischer-Tropsch catalyst. In the Fischer-Tropsch unit, the hydrogen and carbon monoxide react to generate C₂₊ compounds in a Fischer-Tropsch process. The C₂₊ compounds are directed to the fractionation unit to separate the generated C₂₊ compounds into streams each comprising a subset of the generated C₂₊ compounds.

Claims

1. A method for generating hydrocarbon compounds containing at least two carbon atoms (C₂₊ compounds), comprising:

(a) directing a natural gas feed stream comprising methane and C₂₊ compounds to at least one separation unit to separate said methane from said C₂₊ compounds, wherein said natural gas feed stream is from a non-Fischer-Tropsch process;

(b) directing at least a portion of said methane separated in (a) to a syngas unit, and in said syngas unit partially oxidizing said methane to hydrogen (H₂) and carbon monoxide (CO);

(c) directing said hydrogen and carbon monoxide to a Fischer-Tropsch unit comprising a Fischer-Tropsch catalyst, and in said Fischer-Tropsch unit reacting said hydrogen and carbon monoxide in a Fischer-Tropsch process to generate a product stream comprising C₂₊ compounds; and

(d) directing said C₂₊ compounds separated in (a) and said product stream comprising said C₂₊ compounds generated in (c) to a fractionation unit, and in said fractionation unit separating said C₂₊ compounds into individual streams.

2. The method of claim 1, wherein compounds comprising at least 10 carbon atoms are removed from said product stream prior to directing said product stream to said fractionation unit in (d).

3. The method of claim 2, wherein said compounds comprising at least 10 carbon atoms are removed using a refrigerant shared with said fractionation unit.

5. The method of claim 1, wherein said fractionation unit comprises at least one cryogenic separation unit.

6. The method of claim 5, wherein said at least one cryogenic separation unit is a propylene-based cryogenic separation unit.

7. The method of claim 1, wherein said fractionation unit comprises at least one pressure swing adsorption unit.

15. The method of claim 1, further comprising directing C₂₊ compounds generated in (c) to a light hydrocarbon recovery unit, wherein said light hydrocarbon recovery unit generates tail gas.

16. The method of claim 15, further comprising directing said tail gas to said at least one separation unit.

17. The method of claim 1, further comprising directing hydrogen or carbon monoxide recovered in said fractionation unit to said Fischer-Tropsch unit.

18. The method of claim 1, further comprising, prior to (d), directing said C₂₊ compounds generated in (c) to at least one separation unit to separate said C₂₊ compounds from non-C₂₊ impurities comprising one or more of methane, H₂ and CO.

20. The method of claim 18, further comprising directing said non-C₂₊ impurities to said syngas unit or said Fischer-Tropsch unit.

22. The method of claim 1, further comprising, prior to (b), directing a portion of said methane separated from said C₂₊ compounds for use as pipeline gas.

30. The method of claim 1, further comprising, prior to (a), retrofitting said non-Fischer Tropsch process with a Fischer Tropsch process comprising said syngas unit and said Fischer Tropsch unit.

31. The method of claim 30, wherein said non-Fischer-Tropsch process comprises said fractionation unit.

32. The method of claim 1, further comprising, prior to (d), separating hydrocarbon compounds containing at least 30 carbon atoms from said generated C₂₊ compounds.

34. The method of claim 1, further comprising, prior to (d), directing said product stream to a methanation unit to convert CO, CO₂ and H₂ in said product stream to methane.

35. The method of claim 1, further comprising, prior to (d), directing said product stream to a cracking unit to convert alkanes among said C₂₊ compounds to alkenes.

4. (canceled)

8-14. -14. (canceled)

19. (canceled)

21. (canceled)

23-29. -29. (canceled)

33. (canceled)

36-40. -40. (canceled)

41. A system for generating hydrocarbon compounds containing at least two carbon atoms (C₂₊ compounds), comprising:

a. at least one separation unit that (i) accepts a natural gas feed stream comprising methane and C₂₊ compounds from a non-Fischer-Tropsch process and (ii) separates said methane from said C₂₊ compounds;

b. a syngas unit downstream of and fluidically coupled to said at least one separation unit, wherein said syngas unit (i) accepts at least a portion of said methane separated in said at least one separation unit and (ii) partially oxidizes said methane to hydrogen (H₂) and carbon monoxide (CO);

c. a Fischer-Tropsch unit downstream of and fluidically coupled to said syngas unit, wherein said Fischer-Tropsch unit comprises a Fischer-Tropsch catalyst for facilitating a Fischer-Tropsch process, and wherein said Fischer-Tropsch unit (i) accepts said H₂ and said CO and (ii) reacts said H₂ and CO in said Fischer-Tropsch process to generate a product stream comprising C₂₊ compounds; and

d. a fractionation unit downstream of and fluidically coupled to said at least one separation unit and said Fischer-Tropsch unit, wherein said fractionation unit (i) accepts said C₂₊ compounds separated in said at least one separation unit and said product stream comprising said C₂₊ compounds generated in said Fischer-Tropsch unit, and (ii) separates said C₂₊ compounds into individual streams.

42. The system of claim 41, wherein said fractionation unit comprises at least one cryogenic separation unit.

49. The system of claim 41, further comprising a methanation unit that converts CO, carbon dioxide (CO₂), and H₂ in said product stream to methane.

50. The system of claim 41, further comprising a cracking unit that converts alkanes among said C₂₊ compounds to alkenes.

43-48. -48. (canceled)

51-54. -54. (canceled)