US 5,568,737 A · Hydrocarbon gas processing

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said gaseous first stream is cooled and then combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said gaseous first stream is cooled and then combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said second stream is cooled sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said Cs components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said second stream is cooled sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(7) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(8) said compressed recycle stream is cooled sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is cooled to condense substantially all Of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is cooled sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is cooled sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(8) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(9) said compressed recycle stream is cooled sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure and then expanded to said lower pressure and supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(5) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(6) said compressed recycle stream is cooled sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure and then expanded to said lower pressure and supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(5) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(6) said compressed recycle stream is cooled sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(5) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(6) said compressed recycle stream is cooled sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is warmed;
(5) said warmed distillation stream is compressed to higher pressure and thereafter divided into said volatile residue gas fraction and a compressed recycle stream;
(6) said compressed recycle stream is cooled sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first cooling means adapted to cool said feed gas under pressure sufficiently to partially condense it;
(2) separation means connected to said first cooling means to receive said partially condensed feed and to separate it into a vapor and a condensed stream;
(3) first dividing means connected to said separation means to receive said vapor and to divide said vapor into first and second streams;
(4) combining means connected to combine said condensed stream and said first stream into a combined stream;
(5) second cooling means connected to said combining means to receive said combined stream and to cool it sufficiently to substantially condense it;
(6) second expansion means connected to said second cooling means to receive said substantially condensed combined stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded combined stream to said distillation column at a first mid-column feed position;
(7) said first expansion means being connected to said first dividing means to receive said second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(8) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(9) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(10) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(11) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(12) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(13) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said combined stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

19 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first cooling means adapted to cool said feed gas under pressure sufficiently to partially condense it;
(2) separation means connected to said first cooling means to receive said partially condensed feed and to separate it into a vapor and a condensed stream;
(3) first dividing means connected to said separation means to receive said vapor and to divide said vapor into first and second streams;
(4) combining means connected to combine said condensed stream and said first stream into a combined stream;
(5) second cooling means connected to said combining means to receive said combined stream and to cool it sufficiently to substantially condense it;
(6) second expansion means connected to said second cooling means to receive said substantially condensed combined stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded combined stream to said distillation column at a first mid-column feed position;
(7) said first expansion means being connected to said first dividing means to receive said second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(8) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(9) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(10) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(11) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(12) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(13) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said combined stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

19 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first dividing means prior to said first cooling means to divide said feed gas into a first gaseous stream and a second gaseous stream;
(2) second cooling means connected to said dividing means to receive said first stream and to cool it sufficiently to substantially condense it;
(3) second expansion means connected to said second cooling means to receive said substantially condensed first stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded first stream to said distillation column at a first mid-column feed position;
(4) said first cooling means being connected to said first dividing means to receive said second stream and to cool it;
(5) said first expansion means being connected to said first cooling means to receive said cooled second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(6) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(7) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(8) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(9) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(10) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(11) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said first stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

17 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first dividing means prior to said first cooling means to divide said feed gas into a first gaseous stream and a second gaseous stream;
(2) second cooling means connected to said dividing means to receive said first stream and to cool it sufficiently to substantially condense it;
(3) second expansion means connected to said second cooling means to receive said substantially condensed first stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded first stream to said distillation column at a first mid-column feed position;
(4) said first cooling means being connected to said first dividing means to receive said second stream and to cool it;
(5) said first expansion means being connected to said first cooling means to receive said cooled second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(6) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(7) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(8) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(9) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(10) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(11) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said first stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

17 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first dividing means after said first cooling means to divide said cooled stream into a first stream and a second stream;
(2) second cooling means connected to said dividing means to receive said first stream and to cool it sufficiently to substantially condense it;
(3) second expansion means connected to said second cooling means to receive said substantially condensed first stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded first stream to said distillation column at a first mid-column feed position;
(4) said first expansion means being connected to said first dividing means to receive said second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(5) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(6) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(7) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(8) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(9) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(10) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said first stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

16 more elements

In an apparatus for the separation of a gas containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in said apparatus there being

(a) a first cooling means to cool said gas under pressure connected to provide a cooled stream under pressure;
(b) a first expansion means connected to receive at least a portion of said cooled stream under pressure and to expand it to a lower pressure, whereby said stream is further cooled;
and
(c) a fractionation tower connected to said first expansion means to receive said further cooled stream therefrom;
the improvement wherein said apparatus includes
(1) first dividing means after said first cooling means to divide said cooled stream into a first stream and a second stream;
(2) second cooling means connected to said dividing means to receive said first stream and to cool it sufficiently to substantially condense it;
(3) second expansion means connected to said second cooling means to receive said substantially condensed first stream and to expand it to said lower pressure;
said second expansion means being further connected to a distillation column in a lower region of said fractionation tower to supply said expanded first stream to said distillation column at a first mid-column feed position;
(4) said first expansion means being connected to said first dividing means to receive said second stream and to expand it to said lower pressure;
said first expansion means being further connected to said distillation column to supply said expanded second stream to said distillation column at a second mid-column feed position;
(5) heating means connected to said fractionation tower to receive a distillation stream which rises in the fractionation tower and to heat it;
(6) compressing means connected to said heating means to receive said heated distillation stream and to compress it;
(7) second dividing means connected to said compressing means to receive said heated compressed distillation stream and to divide it into said volatile residue gas fraction and a compressed recycle stream;
(8) third cooling means connected to said second dividing means to receive said compressed recycle stream and to cool it sufficiently to substantially condense it;
(9) third expansion means connected to said third cooling means to receive said substantially condensed compressed recycle stream and to expand it to said lower pressure;
said third expansion means being further connected to said fractionation tower to supply said expanded condensed recycle stream to the tower at a top feed position;
and
(10) control means adapted to regulate the pressure of said compressed recycle stream and the quantities and temperatures of said first stream, said second stream and said recycle stream to maintain column overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction.

16 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.s components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gee stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said gaseous first stream is cooled and then combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containinq a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said gaseous first stream is cooled and then combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said second stream is cooled sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said second stream is cooled sufficiently to partially condense it;
(2) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(3) said first stream is combined with at least a portion of said condensed stream to form a combined stream and said combined stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled combined stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(7) said recycle stream is compressed to form a compressed recycle stream;
(8) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(9) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(10) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

14 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially Condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein said gas stream is cooled sufficiently to partially condense it;
and
(1) said partially condensed gas stream is separated thereby to provide a vapor stream and a condensed stream;
(2) said vapor stream is thereafter divided into gaseous first and second streams;
(3) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(4) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(5) said gaseous second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of amid tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gag fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said voltage residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure hereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is cooled sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said fur=her cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is cooled sufficiently to partially condense it;
(4) said partially condensed second stream is separated thereby to provide a vapor stream and a condensed stream;
(5) said vapor stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(6) at least a portion of said condensed stream is expanded to said lower pressure and is supplied to said distillation column at a third mid-column feed position;
(7) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(8) said recycle stream is compressed to form a compressed recycle stream;
(9) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(10) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(11) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

15 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure and then expanded to said lower pressure and supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(5) said recycle stream is compressed to form a compressed recycle stream;
(6) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein prior to cooling, said gas is divided into gaseous first and second streams;
and
(1) said gaseous first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said gaseous second stream is cooled under pressure and then expanded to said lower pressure and supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(5) said recycle stream is compressed to form a compressed recycle stream;
(6) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and a relatively less volatile fraction containing a major portion of said C.sub.2 components, C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expended to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(5) said recycle stream is compressed to form a compressed recycle stream;
(6) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.2 components, C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

In a process for the separation of a gas stream containing methane, C.sub.2 components, C.sub.3 components and heavier hydrocarbon components into a volatile residue gas fraction containing a major portion of said methane and said C.sub.2 components and a relatively less volatile fraction containing a major portion of said C.sub.3 components and heavier components, in which process

(a) said gas stream is cooled under pressure to provide a cooled stream;
(b) said cooled stream is expanded to a lower pressure whereby it is further cooled;
and
(c) said further cooled stream is fractionated at said lower pressure whereby the major portion of said C.sub.3 components and heavier components is recovered in said relatively less volatile fraction;
the improvement wherein following cooling, said cooled stream is divided into first and second streams;
and
(1) said first stream is cooled to condense substantially all of it and is thereafter expanded to said lower pressure whereby it is further cooled;
(2) said expanded cooled first stream is thereafter supplied at a first mid-column feed position to a distillation column in a lower region of a fractionation tower;
(3) said second stream is expanded to said lower pressure and is supplied to said distillation column at a second mid-column feed position;
(4) a distillation stream is withdrawn from an upper region of said tower and is divided into a volatile residue gas fraction and a recycle stream;
(5) said recycle stream is compressed to form a compressed recycle stream;
(6) said compressed recycle stream is cooled with at least a portion of said volatile residue gas fraction sufficiently to substantially condense it;
(7) said substantially condensed compressed recycle stream is expanded to said lower pressure and supplied to said fractionation tower at a top feed position;
and
(8) the quantity and pressure of said compressed recycle stream and the quantities and temperatures of said feed streams to the column are effective to maintain tower overhead temperature at a temperature whereby the major portion of said C.sub.3 components and heavier hydrocarbon components is recovered in said relatively less volatile fraction.

12 more elements

Hydrocarbon gas processing

Life of this patent

Hydrocarbon gas processing

Life of this patent

Abstract

Claims81