Carbon dioxide reduction scheme for NGL processes

• US 6,823,692 B1
• Filed: 02/11/2003
• Issued: 11/30/2004
• Est. Priority Date: 02/11/2002
• Status: Active Grant

• Current Assignee: ABB Lummus Global Inc.
• Original Assignee: ABB Lummus Global Inc.
• Inventors: Patel, Sanjiv, Pan, Justin, Foglietta, Jorge
• Primary Examiner(s): DOERRLER, WILLIAM CHARLES
• Application Number:
  US10/364,073
• Time in Patent Office: 658 Days
• Field of Search: 626/20, 626/17, 629/29
• US Class Current: 62/620
• CPC Class Codes: F25J 2200/02 in a single pressure main column system
• CPC Class Codes: F25J 2200/04 in a dual pressure main column system
• CPC Class Codes: F25J 2200/30 using a side column in a single pressure column system
• CPC Class Codes: F25J 2200/70 Refluxing the column with a condensed part of the feed stream, i.e. fractionator top is stripped or self-rectified
• CPC Class Codes: F25J 2200/76 Refluxing the column with condensed overhead gas being cycled in a quasi-closed loop refrigeration cycle
• CPC Class Codes: F25J 2200/78 Refluxing the column with a liquid stream originating from an upstream or downstream fractionator column
• CPC Class Codes: F25J 2205/02 using simple phase separation in a vessel or drum
• CPC Class Codes: F25J 2205/04 in the feed line, i.e. upstream of the fractionation step
• CPC Class Codes: F25J 2220/66 Separating acid gases, e.g. CO2, SO2, H2S or RSH
• CPC Class Codes: F25J 2235/60 the fluid being (a mixture of) hydrocarbons
• CPC Class Codes: F25J 2240/02 Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream
• CPC Class Codes: F25J 2245/02 Recycle of a stream in general, e.g. a by-pass stream
• CPC Class Codes: F25J 2270/12 External refrigeration with liquid vaporising loop
• CPC Class Codes: F25J 2270/60 Closed external refrigeration cycle with single component refrigerant [SCR], e.g. C1-, C2- or C3-hydrocarbons
• CPC Class Codes: F25J 2290/40 Vertical layout or arrangement of cold equipments within in the cold box, e.g. columns, condensers, heat exchangers etc.
• CPC Class Codes: F25J 2290/80 Retrofitting, revamping or debottlenecking of existing plant
• CPC Class Codes: F25J 3/0209 Natural gas or substitute natural gas
• CPC Class Codes: F25J 3/0233 separation of CnHm with 1 carbon atom or more
• CPC Class Codes: F25J 3/0238 separation of CnHm with 2 carbon atoms or more
• CPC Class Codes: Y10S 62/929 From natural gas

Abstract

An ethane recovery process resulting in a reduction in the amount of carbon dioxide in the recovered NGL stream is provided. To reduce the amount of carbon dioxide, a fractionation tower is provided with a bottom reboiler, and possibly one or more side reboilers higher up in the tower that are integrated with the cooling train. The process disclosed modifies the flow of cold liquid from the separator and tower reboiling to reject some of the more volatile components such as carbon dioxide from the less volatile fraction while maintaining recovery of desirable components such as C2+ hydrocarbon components. The modification includes heating a part of the separator liquid and introducing it at least one stage below the remaining liquid.

Claims

1. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons into a volatile gas fraction containing substantially all the methane and a less volatile hydrocarbon fraction containing a large portion of the C2+ components, the process comprising the steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 such that at least a portion of the inlet gas stream is condensed to produce a first vapor stream and a first liquid stream;

expanding the first vapor stream to a lower pressure, and then supplying a fractionation tower with the vapor stream as a tower feed stream so that the fractionation tower produces a tower bottoms stream containing a less volatile hydrocarbon fraction and a tower overhead stream containing a volatile gas fraction; and

the improvement comprising;

splitting the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a second upper tower food stream; and

heating the third liquid stream and supplying the fractionation tower with the third liquid stream at a return location at least one theoretical stage below the second upper tower feed stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

3. The process of claim 1, wherein the step of supplying and cooling the inlet gas stream includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream.

4. The process of claim 3, wherein the step of cooling at least a portion of the inlet gas stream further includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, the at least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

5. The process of claim 1, wherein the step of expanding the first vapor stream to a lower pressure further includes the steps of:

supplying an expander outlet separator with the first vapor stream and the tower overhead stream thereby forming a separator bottoms stream and a separator overhead stream;

supplying the fractionation tower with the separator bottoms stream as the tower feed stream; and

heating and boosting in pressure the separator overhead stream to form a residue gas stream.

6. The process of claim 5, wherein the step of healing and boosting in pressure the separator overhead stream to form a residue gas stream includes heating the separator overhead stream by heat exchange contact with at least a portion of the inlet gas stream.

7. The process of claim 1, further comprising the steps of:

heating and boosting in pressure the tower overhead stream to form a residue gas stream;

removing at least a portion of the residue gas stream and cooling at least a portion of the residue gas stream to substantially condense at least a portion of the tower overhead stream; and

supplying the fractionation tower with the at least a portion of the substantially condensed tower overhead stream as a top tower feed stream.

8. The process of claim 7, wherein the step of heating and boosting in pressure the tower overhead stream to form a residue gas stream includes heating the tower overhead stream by heat exchange contact with a stream selected from the group consisting of at least a portion of the inlet gas stream, at least a portion of the residue gas stream, and combinations thereof.

9. The process of claim 7, wherein the step of cooling at least a portion of the inlet gas stream further includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, the at least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

2. A process for separating as inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons into a volatile gas fraction containing substantially all the methane end a less volatile hydrocarbon fraction containing a large portion of the C2+ components, the process comprising the steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

expanding the first vapor stream to a lower pressure, and then supplying a fractionation tower with the vapor stream as a tower feed stream so that the fractionation tower produces a tower bottoms stream containing a less volatile hydrocarbon fraction and a tower overhead stream containing a volatile gas fraction; and

the improvement comprising;

splitting the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a second upper tower feed stream;

heating the third liquid stream and supplying the fractionation tower with the third liquid stream at a return location at least one theoretical stage below the second upper tower feed stream, the third liquid stream providing stripping vapors capable of removing CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction; and

maintaining feed stream conditions including maintaining an adequate quantity and temperature of the third liquid stream and an amount of reboiling for the functionation tower so that a quantity of carbon dioxide in the tower bottoms stream is substantially reduced.

10. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

splitting at least a portion of the first vapor stream into a second vapor stream a third vapor stream;

cooling, expanding, and then supplying the fractionation tower with the second vapor stream as a first upper tower feed stream;

expanding the third vapor stream and supplying the fractionation tower with the third vapor stream as a second upper tower feed stream so that the fractionation tower produces a tower bottoms stream containing a less volatile hydrocarbon stream and a tower overhead stream containing a more volatile fraction; and

an improvement to the process comprising the steps of;

splitting the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a middle feed stream; and

heating the third liquid stream and supplying the third liquid stream to the fractionation tower at a location at learnt one theoretical stage below the middle feed stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 as significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

12. The process of claim 10, further including heating and boosting in pressure the tower overhead stream to form a residue gas stream.

13. The process of claim 10, wherein the step of supplying and cooling the inlet gas stream includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid steam.

14. The process of claim 13, wherein the step of cooling at least a portion of the inlet gas stream further includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

15. The process of claim 10, further including the step of cooling the second vapor stream to partially condense at least a portion of the second vapor stream to form a separator overhead steam and a separator bottoms stream.

11. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

splitting at least a portion of the first vapor stream into a second vapor stream and a third vapor stream;

cooling, expanding, and then supplying the fractionation tower with the second vapor stream as a first upper tower feed stream;

expanding the third vapor stream and supplying the fractionation tower with the third vapor stream as a second upper tower feed stream so that the fractionation tower produces a tower bottoms stream containing a less volatile hydrocarbon stream and a tower overhead stream containing a more volatile fraction; and

an improvement to the process comprising the step of;

splitting the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a middle feed stream;

heating the third liquid stream and supplying the third liquid stream to the fractionation tower at a location at least one theoretical stage below the middle feed stream, the third liquid stream providing stripping vapors capable of removing CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction; and

maintaining feed stream conditions including maintaining an adequate quantity and temperature of the third liquid stream and an amount of reboiling for the fractionation tower so that a quantity of carbon dioxide in the tower bottoms stream is substantially reduced.

16. The process of claim 11, further comprising the steps of:

heating and boosting in pressure the tower overhead stream to form a residue gas stream;

removing and cooling at least a portion of the residue gas stream to substantially condense the at least a portion of the residue gas stream; and

supplying the fractionation tower with the at least a portion of the residue gas stream as a top tower food stream.

17. The process of claim 16, wherein the step of heating and boosting in pressure the tower overhead stream to form a residue gas stream includes heating the tower overhead stream by heat exchange contact with a stream selected from the group consisting of the second vapor stream, at least a portion of the inlet gas stream, and combinations thereof.

18. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

splitting at least a portion of the first vapor stream into a second vapor stream and a third vapor stream;

cooling the second vapor stream to substantially condense the second vapor stream and supplying the second vapor stream to an absorber tower as an absorber top feed stream;

expanding the third vapor stream to a lower pressure and then supplying the absorber tower with the third vapor stream as an absorber bottoms feed stream so that the absorber tower produces an absorber overhead stream containing a more volatile fraction of the second and third vapor streams and an absorber bottoms stream containing a less volatile fraction of the second and third vapor streams;

supplying a fractionation tower with the absorber bottoms stream as a top tower feed stream so that the fractionation tower produces a tower bottom stream containing a less volatile hydrocarbon fraction of the inlet gas stream and a tower overhead stream containing a more volatile fraction of the inlet gas stream;

supplying the absorber tower with the tower overhead stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a lower tower feed stream; and

healing and then supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the lower tower feed stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

20. The process of claim 18, wherein the step of supplying the absorber tower with the tower overhead stream includes supplying the absorber tower with the tower overhead stream at a lower absorber feed position.

21. The process of claim 18, wherein the step of supplying the absorber tower with the tower overhead stream includes cooling and at least partially condensing the tower overhead stream and supplying the absorber tower at a second absorber top feed position.

22. The process of claim 18, further including heating and boosting in pressure the absorber overhead stream to form a residue gas stream.

23. The process of claim 22, wherein the step of heating and boosting in pressure the absorber overhead stream to form a residue gas stream includes the step of heating the absorber overhead stream by heat exchange contact with a stream selected from the group consisting of the tower overhead stream, the second vapor stream, at least a portion of the inlet gas stream, and combinations thereof.

24. The process of claim 18, wherein the step of supplying and cooling the inlet gas stream includes the step of cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, the at least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

19. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon strewn containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

splitting at least a portion of the first vapor stream into a second vapor stream and a third vapor stream;

cooling the second vapor stream to substantially condense the second vapor stream and supplying the second vapor stream to an absorber tower as an absorber top feed stream;

expanding the third vapor stream to a lower pressure and then supplying the absorber tower with the third vapor stream as an absorber bottoms feed stream so that the absorber tower produces an absorber overhead stream containing a more volatile function of the second and third vapor streams and an absorber bottoms stream containing a less volatile fraction of the second and third vapor streams;

supplying a fractionation tower with the absorber bottoms stream as a top tower feed stream so that the fractionation tower produces a tower bottoms stream containing a less volatile hydrocarbon fraction of the inlet gas stream and a tower overhead stream containing a more volatile fraction of the inlet gas stream;

supplying the absorber tower with the tower overhead stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream as a lower tower feed stream;

heating and that supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the lower tower feed stream, the third liquid stream providing stripping vapors capable of removing CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction; and

maintaining feed stream conditions including maintaining an adequate quantity and temperature of the third liquid stream and an amount of reboiling for the fractionation tower so that a quantity of carbon dioxide in the tower bottoms stream is substantially reduced.

25. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling the inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

expanding the first vapor stream to a lower pressure, and then supplying an absorber tower with the first vapor stream as an absorber bottom feed stream so that the absorber tower produces an absorber overhead stream and an absorber bottoms stream;

supplying the absorber bottoms stream to a fractionation tower as top tower feed stream so that the fractionation tower produces a tower overhead stream and a tower bottoms stream;

heating and boosting in pressure the absorber overhead stream to form a residue gas stream;

removing and then cooling at least a portion of the residue gas stream so that the at least a portion of the residue gas stream is substantially condensed;

supplying the absorber tower with the at least a portion of the residue gas stream as a top absorber feed stream;

supplying the absorber tower with the tower overhead stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying fractionation tower with the second liquid stream as a first lower tower feed stream; and

heating and then supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the first lower tower feed stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

27. The process of claim 25, wherein the step of supplying the absorber tower with the tower overhead stream includes supplying the absorber tower with the tower overhead stream at a lower absorber feed position.

28. The process of claim 25, wherein the step of supplying the absorber tower with the tower overhead stream includes cooling and at least partially condensing the tower overhead stream and supplying the absorber tower at an upper absorber feed position.

29. The process of claim 25, wherein the step of supplying the cooling the inlet gas stream includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, the at least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

30. The process of claim 25, wherein the step of heating and boosting in pressure the absorber overhead stream to form a residue gas stream includes heating the absorber overhead stream by heat exchange contact with a stream selected from the group consisting of the tower overhead stream, the at least a portion of the residue gas stream, the at least a portion of the inlet gas stream, and combinations thereof.

31. The process of claim 25, wherein the step of supplying an absorber tower with the first vapor stream includes supplying an absorber tower having at least one mass transfer zone contained therein with the first vapor stream.

26. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling the inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

expanding the first vapor stream to a lower pressure, and then supplying an absorber tower with the first vapor stream as an absorber bottom feed stream so that the absorber tower produces an absorber overhead stream and an absorber bottoms stream;

supplying the absorber bottoms stream to a fractionation tower as top tower feed stream so that the fractionation tower produces a tower overhead stream and a tower bottoms stream;

heating and boosting in pressure the absorber overhead stream to turn a residue gas stream;

removing and then cooling at least a portion of the residue gas stream so that the at least a portion of the residue gas stream is substantially condensed;

supplying the absorber tower with the at least a portion of the residue gas stream as a top absorber feed stream;

supplying the absorber tower with the tower overhead stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying fractionation tower with the second liquid stream as a first lower tower feed stream;

heating and than supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the first lower tower feed stream, the third liquid stream providing stripping vapor capable of removing CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction; and

maintaining feed stream conditions including maintaining an adequate quantity and temperature of the third liquid stream and an amount of reboiling for the fractionation tower so that a quantity of carbon dioxide in the tower bottoms stream is substantially reduced.

32. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling the inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

dividing the first vapor stream into a second vapor stream and a third vapor stream;

cooling and at least partially condensing the second vapor stream thereby forming a flash separator bottoms stream and a flash separator overhead stream and expanding the third vapor stream;

cooling the flash separator overhead stream and supplying an absorber tower with the flash separator overhead stream as a first upper absorber feed stream, the flash separator bottoms stream a first lower absorber feed stream, and the third vapor stream as a second lower absorber feed stream to thereby produce an absorber overhead stream and an absorber bottoms stream;

supplying a fractionation tower with the absorber bottoms stream as an upper tower feed stream to thereby produce a tower overhead stream and a tower bottoms stream;

heating and boosting in pressure the absorber overhead stream to form a residue gas stream;

removing and cooling at least a portion of the residue gas stream so that the at least a portion of the residue gas stream is substantially condensed;

supplying the absorber tower with the tower overhead stream and the at least a portion of the residue gas stream as a second upper absorber feed stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at last a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream; and

heating and supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the second liquid stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

34. The process of claim 32, wherein the step of supplying the absorber tower with the tower overhead stream includes supplying the absorber tower with the tower overhead stream at a tower absorber feed position.

35. The process of claim 32, wherein the step of supplying the absorber tower with the tower overhead stream includes cooling and at least partially condensing the tower overhead stream and supplying the absorber tower at an upper absorber feed position.

36. The process of claim 32, wherein the step of supplying and cooling the inlet gas stream includes cooling at least a portion of the inlet gas stream by heat exchange contact with the third liquid stream and at least one tower reboiler stream, the at least one tower reboiler stream being removed from the fractionation tower at a removal location and being returned at a return location located at essentially a same theoretical stage within the fractionation tower as the removal location.

37. The process of claim 32, wherein the step of heating and boosting in pressure the absorber overhead stream to form a residue gas stream includes heating the absorber overhead stream by heat exchange contact with a stream selected from the group consisting of the tower overhead stream, the at least a portion of the residue gas stream, the at least a portion of the inlet gas stream, the second vapor stream, the flash separator overhead stream, and combinations thereof.

38. The process of claim 32, wherein the step of supplying absorber tower with the flash separator overhead stream includes supplying an absorber tower having at least one mass transfer zone contained therein with the flash separator overhead stream.

33. A process for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the process comprising steps of:

supplying and cooling the inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

dividing the first vapor stream into a second vapor stream and a third vapor stream;

cooling and at least partially condensing the second vapor stream thereby forming a flash separator bottoms stream and a flash separator overhead stream and expanding the third vapor stream;

cooling the flash separator overhead stream and supplying an absorber tower with the flash separator overhead stream as a first upper absorber feed stream, the flash separator bottoms stream as a first lower absorber feed stream, and the third vapor stream as a second lower absorber feed stream to thereby produce an absorber overhead stream and an absorber bottoms stream;

supplying a fractionation tower with the absorber bottoms stream as an upper tower feed stream to thereby produce a tower overhead stream and a tower bottoms stream;

heating and boosting in pressure the absorber overhead stream to form a residue gas stream;

removing and cooling at least a portion of the residue gas stream so that the at least a portion of the residue gas stream is substantially condensed;

supplying the absorber tower with the tower overhead stream and the at least a portion of the residue gas stream as a second upper absorber feed stream; and

an improvement to the process comprising the steps of;

dividing the first liquid stream into at least a second liquid stream and a third liquid stream;

supplying the fractionation tower with the second liquid stream;

heating and supplying the fractionation tower with the third liquid stream at a location at least one theoretical stage below the second liquid stream, the third liquid stream providing stripping vapors capable of removing CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction; and

maintaining feed stream conditions including maintaining an adequate quantity and temperature of the third liquid stream and an amount of rebelling for the fractionation tower so that a quantity of carbon dioxide in the tower bottoms stream is substantially reduced.

39. An apparatus for separating an inlet gas stream containing methane, C2 components, C3 components and heavier hydrocarbons, into a residue gas stream containing substantially all the methane and more volatile components and a less volatile hydrocarbon stream containing C2 components, C3 and heavier components, the apparatus comprising:

an inlet heat exchanger for cooling an inlet gas stream having a quantity of CO2 to partially condense at least a portion of the inlet gas stream to produce a first vapor stream and a first liquid stream;

an expander for expending the first vapor stream to a lower pressure;

a fractionation tower for receiving a tower feed stream and producing a tower bottoms stream containing a less volatile hydrocarbon fraction and a tower overhead stream containing a more volatile gas fraction;

at least one side reboiler that removes that returns a tower reboiler stream from essentially a same theoretical stage with the fractionation tower, the side reboiler heats the more volatile gas fraction higher in the fractionation tower thereby preventing the more volatile gas fraction from reaching a bottom of the fractionation tower and reducing an amount of the more volatile gas fraction recovered in the tower bottoms stream; and

a splitter for splitting the first liquid stream into at least a second liquid stream and a third liquid stream, the second liquid stream being supplied to the fractionation tower as a second upper tower feed stream and the third liquid stream being heated and supplied to the fractionation lower at a return location at least one theoretical stage below the second upper tower feed stream, the third liquid stream providing stripping vapors to remove CO2 from the liquid descending down the fractionation tower such that the quantity of CO2 is significantly reduced in the less volatile hydrocarbon fraction or ethane is significantly increased while the quantity of CO2 is substantially maintained in the less volatile hydrocarbon fraction.

40. The apparatus of claim 39, further including an absorber tower for receiving a first vapor stream and producing an absorber overhead stream and an absorber bottoms stream.