Process for producing olefins

• US 20060004239A1
• Filed: 07/01/2004
• Published: 01/05/2006
• Est. Priority Date: 07/01/2004
• Status: Active Grant

• Current Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Brinen, Jeffrey L., Kuechler, Keith H., Ruziska, Philip Andrew
• Granted Patent: US 7,279,012 B2
• Time in Patent Office: Days
• US Class Current: 585/639
• CPC Class Codes: C07C 11/04 Ethylene
• CPC Class Codes: C07C 11/06 Propene
• CPC Class Codes: Y02P 30/20 using bio-feedstock
• CPC Class Codes: Y02P 30/40 Ethylene production

Abstract

A process for producing olefins comprises providing a vapor product stream from an oxygenate to olefin reaction, the vapor product stream comprising C₂ to C₄ olefins, C₂ to C₆ carbonyl compounds and water. The vapor product stream is cooled to provide a first vapor effluent stream comprising no more than 10 wt. % water, and a liquid water-rich stream. The first vapor effluent stream, and a first wash flash vapor stream, are compressed from a first pressure to a second pressure greater than said first pressure to form a second vapor effluent stream, which is then cooled to form a cooled second effluent stream that is at least partially in the vapor state. At least part of the cooled second effluent stream is washed with a liquid alcohol-containing stream, at a third pressure greater than the first pressure but not greater than the second pressure, to produce a wash liquid stream, which comprises C₃ and C₄ olefins, and a wash vapor stream, which contains less C₂ to C₆ carbonyl compounds than the first vapor effluent stream. The wash liquid stream is exposed to a pressure of at least the first pressure but less than the third pressure to form a first wash flash liquid stream and the first wash flash vapor stream, the first wash flash vapor stream being provided for compression with the first vapor effluent stream.

Claims

1. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin reaction, said vapor product stream comprising C₂ to C₄ olefins, C₂ to C₆ carbonyl compounds and water;

(b) cooling said vapor product stream to provide a first vapor effluent stream comprising no more than 10 wt. % water, and a liquid water-rich stream;

(c) compressing the first vapor effluent stream and a first wash flash vapor stream from a first suction pressure to a second pressure greater than said first pressure to form a second vapor effluent stream;

(d) cooling the second vapor effluent stream to form a cooled second effluent stream that is at least partially in the vapor state;

(e) washing at least part of the cooled second effluent stream with a liquid alcohol-containing stream, at a third pressure greater than the first suction pressure but not greater than the second pressure, to produce a wash liquid stream comprising C₃ and C₄ olefins, and a wash vapor stream, said wash vapor stream having a lower content of C₂ to C₆ carbonyl compounds than the first vapor effluent stream; and

(f) exposing the wash liquid stream to a pressure of at least the first suction pressure but less than the third pressure to form a first wash flash liquid stream and said first wash flash vapor stream, said first wash flash vapor stream being provided for compression (c).

2. The process of claim 1 wherein said cooling (b) is conducted in an indirect heat exchanger or in a direct contact quenching device.

3. The process of claim 1 wherein said cooling (b) is conducted in a direct contact quenching device.

4. The process of claim 1 wherein the first vapor effluent stream comprises from about 0.5 to about 5 wt % of said carbonyl compounds.

5. The process of claim 1 wherein the first vapor effluent stream comprises from about 1 to about 4 wt % of said carbonyl compounds.

6. The process of claim 1 wherein the first vapor effluent stream comprises no more than 5 wt % water.

7. The process of claim 1 wherein the first vapor effluent stream comprises no more than 2 wt % water.

8. The process of claim 1 wherein said first vapor effluent stream produced in (b) is at an initial pressure of from about 1 psig to about 100 psig (108 to 790 kPa).

9. The process of claim 1 wherein said first vapor effluent stream produced in (b) is at an initial pressure of from about 5 psig to about 80 psig (135 to 653 kPa).

10. The process of claim 1 wherein said first suction pressure is no more than 40 psi (275 kPa) below the pressure of said first vapor effluent stream produced in (b).

11. The process of claim 1 wherein said first suction pressure is no more than 10 psi (69 kPa) below the pressure of said first vapor effluent stream produced in (b).

12. The process of claim 1 wherein the temperature of the first vapor effluent stream is about 70°

F. (21°

C.) to about 120°

F. (49°

C.).

13. The process of claim 1 wherein the temperature of the first vapor effluent stream is about 80°

F. (27°

C.) to about 110°

F. (43°

C.).

14. The process of claim 1 wherein said second pressure is at least 50 psig (445 kPa) and no greater than 350 psig (2514 kPa).

15. The process of claim 1 wherein said second pressure is at least 100 psig (790 kPa) and no greater than 200 psig (1480 kPa).

16. The process of claim 1 wherein said cooling (d) produces said cooled second effluent stream with a temperature of about 70°

F. (21°

C.) to about 120°

F. (49°

C.).

17. The process of claim 1 wherein said cooling (d) produces said cooled second effluent stream with a temperature of about 80°

F. (27°

C.) to about 110°

F. (43°

C.).

18. The process of claim 1 wherein said liquid alcohol-containing stream used in said washing (e) comprises methanol.

19. The process of claim 1 wherein the temperature in said washing (e) is about 80°

F. (27°

C.) to about 120°

F. (49°

C.).

20. The process of claim 1 wherein the temperature in said washing (e) is about 90°

F. to about 110°

F. (43°

C.).

21. The process of claim 1 wherein said third pressure is at least 50 psig (445 kPa) and no greater than 350 psig (2514 kPa).

22. The process of claim 1 wherein said third pressure is at least 100 psig (790 kPa) and no greater than 200 psig (1480 kPa).

23. The process of claim 1 wherein said wash liquid stream comprises at least 1 wt. % C₃ and C₄ olefins.

24. The process of claim 1 wherein said wash liquid stream comprises at least 5 wt. % C₃ and C₄ olefins.

25. The process of claim 1 wherein said wash liquid stream comprises at least 10 wt. % C₃ and C₄ olefins.

26. The process of claim 1 wherein said wash liquid stream comprises at least 20 wt. % C₃ and C₄ olefins.

27. The process of claim 1 wherein said wash liquid stream comprises no greater than 50 wt. % C₃ and C₄ olefins.

28. The process of claim 1 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 50 wt. % C₃ and C₄ olefins.

29. The process of claim 1 wherein said vapor product stream in (a) further comprises C₅ olefins, and said wash liquid stream further comprises C₅ olefins.

30. The process of claim 29 wherein said wash liquid stream comprises at least 1 wt. % C₃ to C₅ olefins.

31. The process of claim 29 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 60 wt. % C₃ to C₅ olefins.

32. The process of claim 1 wherein the pressure employed in the exposing (f) is from about 1 psig to about 100 psig (108 to 790 kPa).

33. The process of claim 1 wherein the pressure employed in the exposing (f) is from about 5 psig to about 80 psig (135 to 653 kPa).

34. The process of claim 1 wherein the temperature employed in the exposing (f) is about 40°

F. (4°

C.) to about 120°

F. (49°

C.).

35. The process of claim 1 wherein the temperature employed in the exposing (f) is about 60°

F. (16°

C.) to about 110°

F. (43°

C.).

36. The process of claim 1 wherein the cooling (d) produces a cooled second vapor effluent stream and a second liquid effluent stream, said cooled second vapor effluent stream vapor being washed in (e), and said second liquid effluent stream being exposed to a pressure of at least the first suction pressure and no greater than the third pressure to form a second wash flash liquid stream and a second wash flash vapor stream, said second wash flash vapor stream also being provided for compression (c).

37. The process of claim 36 wherein the exposing (f) occurs in a vessel, and the second liquid effluent stream is also introduced to said vessel to provide the first and second wash flash vapor streams as a common stream for compression (c), and the first and second wash flash liquid streams as a common stream.

38. The process of claim 37 wherein the second liquid effluent stream is combined with the wash liquid stream prior to being introduced to said vessel.

39. The process of claim 37 wherein the first vapor effluent stream is also introduced to the vessel used in (f), whereby the first vapor effluent stream, and the first and second wash flash vapor streams are provided as a common stream for compression (c).

40. The process of claim 1 wherein the cooling (b) and exposing (f) are effected in the same device to provide the first vapor effluent stream and first wash flash vapor stream as a common stream for compression (c), and the liquid water-rich stream and first wash flash liquid stream as a common stream.

41. The process of claim 36 wherein the cooling (b) and exposing (f) are effected in the same device, and the second liquid effluent stream is also provided to said device, to provide the first effluent stream, the first wash flash vapor stream and the second wash flash vapor stream as a combined stream for compression (c) and the liquid water-rich stream and first wash flash liquid stream and the second wash flash liquid stream as a common stream.

42. The process of claim 41 wherein the second liquid effluent stream is combined with the wash liquid stream prior to being provided to said device.

43. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin reaction, said product comprising C₂ to C₄ olefins, C₂ to C₆ carbonyl compounds and water;

(b) cooling said vapor product stream to provide a first vapor effluent stream at a first pressure and comprising no more than 10 wt. % water, and a liquid water-rich stream;

(c) compressing the first vapor effluent stream from a first suction pressure that is no greater than said first pressure to an intermediate pressure greater than said first pressure to form an intermediate effluent stream;

(d) cooling the intermediate effluent stream to form an intermediate effluent vapor stream and an intermediate effluent liquid stream;

(e) compressing the intermediate effluent vapor stream from an intermediate suction pressure that is no greater than said intermediate pressure to a second pressure greater than said intermediate pressure to form a second effluent stream;

(f) cooling the second effluent stream to form a cooled second effluent stream that is at least partially vapor;

(g) washing at least part of the cooled second effluent stream with a liquid alcohol-containing stream in a vapor-liquid contacting device, at a third pressure greater than the intermediate suction pressure but not greater than the second pressure, to produce a wash liquid stream comprising C₃ and C₄ olefins, and a wash vapor stream, said wash vapor stream having a lower content of C₂ to C₆ carbonyl compounds than the first vapor effluent stream; and

(h) exposing at least part of the wash liquid stream to a pressure of at least the first suction pressure and less than the third pressure to form a first wash flash liquid stream and a first wash flash vapor stream, said first wash flash vapor stream being provided for compression (c) along with the first vapor effluent stream, or for compression (e) along with the intermediate effluent vapor stream, or both.

44. The process of claim 43 wherein said cooling (b) is conducted in an indirect heat exchanger or in a direct contact quenching device.

45. The process of claim 43 wherein said cooling (b) is conducted in a direct contact quenching device.

46. The process of claim 43 wherein said first pressure is from about 1 psig to about 100 psig (108 to 790 kPa).

47. The process of claim 43 wherein said first pressure is from about 5 psig to about 80 psig (135 to 653 kPa).

48. The process of claim 43 wherein said first suction pressure is no more than 40 psi (275 kPa) below said first pressure.

49. The process of claim 43 wherein said first suction pressure is no more than 10 psi (69 kPa) below said first pressure.

50. The process of claim 43 wherein said intermediate pressure is greater than 5 psig (135 kPa) and less than 350 psig (2514 kPa).

51. The process of claim 43 wherein said intermediate pressure is greater than 40 psig (376 kPa) and less than 200 psig (1480 kPa).

52. The process of claim 43 wherein said intermediate suction pressure is no more than 30 psi (206 kPa) below said intermediate pressure.

53. The process of claim 43 wherein said intermediate suction pressure is no more than 10 psi (69 kPa) below said intermediate pressure.

54. The process of claim 43 wherein said second pressure is greater than 100 psig (790 kPa) and less than 350 psig (2514 kPa).

55. The process of claim 43 wherein said second pressure is greater than 140 psig (1066 kPa). and less than 200 psig (1480 kPa).

56. The process of claim 43 wherein said third pressure is greater than 100 psig (790 kPa) and less than 350 psig (2514 kPa).

57. The process of claim 43 wherein said third pressure is greater than 140 psig (1066 kPa). and less than 200 psig (1480 kPa).

58. The process of claim 43 wherein said wash liquid stream comprises at least 1 wt. % C₃ and C₄ olefins.

59. The process of claim 43 wherein said wash liquid stream comprises at least 5 wt. % C₃ and C₄ olefins.

60. The process of claim 43 wherein said wash liquid stream comprises at least 10 wt. % C₃ and C₄ olefins.

61. The process of claim 43 wherein said wash liquid stream comprises at least 20 wt. % C₃ and C₄ olefins.

62. The process of claim 43 wherein said wash liquid stream comprises no greater than 50 wt. % C₃ and C₄ olefins.

63. The process of claim 43 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 50 wt. % C₃ and C₄ olefins.

64. The process of claim 43 wherein said vapor product stream in (a) further comprises C₅ olefins, and said wash liquid stream further comprises C₅ olefins.

65. The process of claim 64 wherein said wash liquid stream comprises at least 1 wt. % C₃ to C₅ olefins.

66. The process of claim 64 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 60 wt. % C₃ to C₅ olefins.

67. The process of claim 43 wherein the pressure employed in the exposing (h) is from about 1 psig to about 350 psig (108 to 2514 kPa).

68. The process of claim 43 wherein the pressure employed in the exposing (h) is from about 5 psig to about 200 psig (135 to 1480 kPa).

69. The process of claim 43 wherein said intermediate effluent liquid stream is exposed to a pressure of at least the first suction pressure and less than the intermediate pressure to provide an intermediate flash vapor effluent stream and an intermediate flash liquid effluent stream, and said intermediate flash vapor effluent stream is provided for compression to a pressure no greater than said intermediate pressure.

70. The process of claim 69 wherein said intermediate flash vapor effluent stream is provided for compression (c) along with said first vapor product effluent stream.

71. The process of claim 70 wherein exposing of said intermediate effluent liquid stream occurs in a vessel, and said first vapor product stream is also introduced to said vessel to provide the intermediate flash vapor effluent stream and first vapor product stream as a common stream for compression (c).

72. The process of claim 43 wherein the cooling (f) produces a cooled second vapor effluent stream and a second liquid effluent stream, said cooled second vapor effluent stream being provided for washing (g), and said second liquid effluent stream being exposed to a pressure of at least the first suction pressure and no greater than the third pressure to form a second wash flash liquid stream and a second wash flash vapor stream, said second wash flash vapor stream also being provided for compression (c) along with the first effluent stream, or for compression (e) along with the intermediate effluent vapor stream, or both.

73. The process of claim 72 wherein said second liquid effluent stream is exposed to a pressure of at least the intermediate suction pressure and said second wash flash vapor stream is provided for compression (e) along with the intermediate effluent vapor stream.

74. The process of claim 72 wherein the cooled second effluent stream is introduced into a vessel to form the cooled second vapor effluent stream and the second liquid effluent stream.

75. The process of claim 43 wherein the wash liquid stream in (h) is exposed to a pressure of at least the intermediate suction pressure and said first wash flash vapor stream is provided for compression (e) along with the intermediate effluent vapor stream.

76. The process of claim 75 wherein exposing (h) occurs in a vessel, and the second liquid effluent stream is also introduced to said vessel to provide the first wash flash vapor stream and second wash flash vapor stream as a common stream for compression (c), or compression (e), or both, and to provide the first wash flash liquid and the second wash flash liquid as a common stream.

77. The process of claim 75 wherein the second liquid effluent stream is combined with said wash liquid stream prior to being introduced to said vessel.

78. The process of claim 75 wherein the cooled intermediate effluent stream from (d) is also introduced into the vessel to provide the first wash flash vapor stream and the second wash flash vapor stream and the intermediate effluent vapor stream as a common stream for compression (e), and the first wash flash liquid and the second wash flash liquid and the intermediate effluent liquid stream as a common stream.

79. The process of claim 78 wherein the cooled intermediate effluent stream from (d) is combined with the second liquid effluent stream and/or the wash liquid stream prior to being introduced into the vessel.

80. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin reaction, said product comprising C₂ to C₄ olefins, C₂ to C₆ carbonyl compounds and water;

(b) cooling said vapor product stream to provide a first vapor effluent stream at a first pressure and comprising no more than 10 wt. % water, and a liquid water-rich stream;

(c) introducing the first vapor effluent stream and an intermediate effluent liquid stream into a first vessel to form a flash vapor added first effluent stream and a first vessel liquid stream;

(d) compressing the flash vapor added first effluent stream to an intermediate pressure to form an intermediate effluent stream;

(e) cooling the intermediate effluent stream and introducing said cooled intermediate effluent stream into a second vessel together with a second liquid effluent stream and a wash liquid stream to form an intermediate effluent vapor stream and said intermediate effluent liquid stream;

(f) compressing the intermediate effluent vapor stream to a second pressure greater than said intermediate pressure to form a second effluent stream;

(g) cooling the second effluent stream and introducing said cooled second effluent stream into a third vessel to form a cooled second vapor effluent stream and said second liquid effluent stream; and

(h) washing the cooled second vapor effluent stream with an liquid alcohol-containing stream in a vapor-liquid contacting device, at a third pressure of greater than the intermediate pressure but no greater than the second pressure, to produce said wash liquid stream comprising C₃ and C₄ olefins, and a wash vapor stream, said wash vapor stream having a lower content of C₂ to C₆ carbonyl compounds than the first effluent stream.

81. The process of claim 80 wherein said cooling (b) is conducted in an indirect heat exchanger or in a direct contact quenching device.

82. The process of claim 80 wherein said cooling (b) is conducted in a direct contact quenching device.

83. The process of claim 80 wherein said first pressure is from about 1 psig to about 100 psig (108 to 790 kPa).

84. The process of claim 80 wherein said first vapor effluent stream and the intermediate effluent liquid stream are combined before being introduced into said first vessel in (c).

85. The process of claim 80 wherein said intermediate pressure is greater than 40 psig (376 kPa) and less than 350 psig (2514 kPa).

86. The process of claim 80 wherein said second pressure is greater than 100 psig (790 kPa) and less than 350 psig (2514 kPa).

87. The process of claim 80 wherein said third pressure is greater than 100 psig (790 kPa) and less than 350 psig (2514 kPa).

88. The process of claim 80 wherein said wash liquid stream comprises at least 1 wt. % C₃ and C₄ olefins.

89. The process of claim 80 wherein said wash liquid stream comprises at least 5 wt. % C₃ and C₄ olefins.

90. The process of claim 80 wherein said wash liquid stream comprises at least 10 wt. % C₃ and C₄ olefins.

91. The process of claim 80 wherein said wash liquid stream comprises at least 20 wt. % C₃ and C₄ olefins.

92. The process of claim 80 wherein said wash liquid stream comprises no greater than 50 wt. % C₃ and C₄ olefins.

93. The process of claim 80 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 50 wt. % C₃ and C₄ olefins.

94. The process of claim 80 wherein said vapor product stream in (a) further comprises C₅ olefins, and said wash liquid stream further comprises C₅ olefins.

95. The process of claim 94 wherein said wash liquid stream comprises at least 1 wt. % C₃ to C₅ olefins.

96. The process of claim 94 wherein said wash liquid stream comprises at least 1 wt. % and no greater than 60 wt. % C₃ to C₅ olefins.

97. The process of claim 80 wherein the second liquid effluent stream is combined with said wash liquid stream prior to being introduced into said second vessel.