Steam injection including alpha-olephin sulfonate dimer surfactant additives and a process of stimulating hydrocarbon recovery from a subterranean formation

Claim 2

A process for recovering hydrocarbons from a subterranean hydrocarbon bearing formation penetrated by at least one injection well and at least one production well, said process comprising: forming a steam and alpha-olefin sulfonate dimer foam; passing said steam and alpha-olefin sulfonate dimer foam into said formation and away from an injection well to assist the movement of hydrocarbons toward a production well; and recovering hydrocarbons at said production well.

Claim 3

The process according to claim 1 wherein the dimer comprises from about 0.01% to about 10% of the water phase of the steam.

Claim 4

The process according to claim 2 wherein a non-condensible gas in an amount of from about 1% to about 50% of the gaseous phase of said steam is injected into said steam prior to the injection of said steam at the injection well.

Claim 5

The process according to claim 3 wherein the non-condensible gas is selected from the group consisting of nitrogen, carbon dioxide, air, flue gas, CH 4 , and carbon monoxide.

Claim 6

The process according to claim 4 wherein the alpha-olefin sulfonate dimer includes alpha-olefin sulfonate dimer in the range of C 10 -C 48 .

Claim 7

The process according to claim 5 further comprising injecting substantially pure steam into the formation prior to the injection of said steam and alpha-olefin sulfonate dimer foam.

Claim 8

The process according to claim 6 wherein substantially pure steam is injected into the formation after the injection of said steam and alpha-olefin sulfonate dimer.

Claim 9

The process according to claim 7 wherein the steam injection is tapered into a steam and alpha-olefin sulfonate dimer injection which is tapered into a steam injection.

Claim 10

The process according to claim 8 wherein the alpha-olefin sulfonate dimer is injected in its salt form or the acid form.

Claim 11

The process according to claim 9 wherein said alpha-olefin sulfonate dimer includes alpha-olefin sulfonate dimer in the range of C 22 -C 40 .

Claim 12

The process according to claim 10 wherein the alpha-olefin sulfonate dimer is synthesized according to the oligomerization process which comprises heating in the liquid phase the sulfonation product of the reaction of sulfur trioxide with a straight chain alkene hydrocarbon having a carbon atom content in the range of from about 5 to 24, wherein the heating is at a temperature above about 110° C. and below the carbonization temperature of the sulfonate, is effected in the substantial absence of water, and is continued for a period at least sufficient for a significant conversion of the sulfonate feed to the corresponding oligomeric disulfonic acid and wherein the resulting oligomeric sulfonic acid is neutralized with ammonia, an alkali metal base, a calcium base, a magnesium base or a mixture thereof.

Claim 13

The process according to claim 11 wherein said straight chain alkene hydrocarbon is a mixture in the range of C 5 -C 24 .

Claim 14

The process according to claim 12 wherein said straight chain alkene hydrocarbon mixture is in the range of C 11 -C 20 .

Claim 15

The process according to claim 1 wherein the alpha-olefin sulfonate dimer includes alpha-olefin sulfonate dimer in the range of C 10 -C 48 .

Claim 16

The process according to claim 14 wherein the alpha-olefin sulfonate dimer includes a mixture of alpha-olefin sulfonate dimer in the range of C 10 -C 48 .

Claim 17

The process according to claim 15 wherein the alpha-olefin sulfonate timer is synthesized according to the alpha-olefin sulfonate dimer is synthesized according to the oligomerization process which comprises heating in the liquid phase the sulfonation product of the reaction of sulfur trioxide with a straight chain alkene hydrocarbon having a carbon atom content in the range of from about 5 to 24, wherein the heating is at a temperature above about 110° C. and below the carbonization temperature of the sulfonate, is effected in the substantial absence of water, and is continued for a period at least sufficient for a significant conversion of the sulfonate feed to the corresponding oligomeric disulfonic acid.

Claim 18

The process according to claim 16 wherein said straight chain alkene hydrocarbon is a mixture in the range of C 5 -C 24 .

Claim 19

The process according to claim 17 wherein said straight chain alkene hydrocarbon mixture is in the range of C 11 -C 20 .

Claim 20

The process according to claim 18 wherein a non-condensible gas in an amount of from about 1% to about 50% of the gaseous phase of said steam is injected with said steam at the injection well.

Claim 21

The process according to claim 14 wherein said alpha-olefin sulfonate dimer includes alpha-olefin sulfonate dimer in the range of C 22 -C 40 .

Claim 22

The process according to claim 20 wherein the alpha-olefin sulfonate dimer includes a mixture of alpha-olefin sulfonate dimer in the range of C 22 -C 40 .

Claim 23

A process for recovering hydrocarbons from a subterranean hydrocarbon bearing formation penetrated by at least one injection well and at least one production well, said process comprising: forming a steam and alpha-olefin sulfonate dimer foam; injecting said steam and alpha-olefin sulfonate dimer foam at an injection well and into said formation; continuing to inject said steam and alpha-olefin sulfonate dimer foam through said injection well and into said formation to assist the movement of hydrocarbons towards a production well; and recovering hydrocarbons from a production well.

Claim 24

A process for recovering hydrocarbons from a subterranean hydrocarbon bearing formation penetrated by at least one injection well and at least one production well, said process comprising: forming a steam and alpha-olefin sulfonate dimer foam; injecting said steam and alpha-olefin sulfonate dimer foam at an injection well and into said formation; continuing to inject said steam and alpha-olefin sulfonate dimer foam through said injection well and into said formation to assist the movement of hydrocarbons towards a production well; and recovering hydrocarbons from a production well.

Claim 25

The process according to claim 22 wherein the dimer comprises from about 0.01% to about 10% of the liquid phase of the steam.

Claim 26

The process according to claim 23 wherein said foam further contains a non-condensible gas selected from the group consisting of nitrogen, carbon dioxide, air, flue gas, CH 4 , and carbon monoxide.

Claim 27

The process according to claim 24 wherein said alpha-olefin sulfonate dimer includes alpha-olefin sulfonate dimer in the range of C 22 -C 40 .

Claim 28

The process according to claim 24 wherein the alpha-olefin sulfonate dimer is synthesized according to the oligomerization process which comprises heating in the liquid phase the sulfonation product of the reaction of sulfur trioxide with a straight chain alkene hydrocarbon having a carbon atom content in the range of from about 5 to 24, wherein the heating is at a temperature above about 110° C. and below the carbonization temperature of the sulfonate, is effected in the substantial absence of water, and is continued for a period at least sufficient for a significant conversion of the sulfonate feed to the corresponding oligomeric disulfonic acid and wherein the resulting oligomeric sulfonic acid is neutralized with ammonia, an alkali metal base, a calcium base, a magnesium base or a mixture thereof.

Claim 29

The process according to claim 26 wherein said straight chain alkene hydrocarbon is a mixture of C 5 -C 24 hydrocarbons.

Claim 30

The process according to claim 27 wherein said mixture is a C 11 -C 20 mixture.

Claim 31

The process according to claim 27 wherein said mixture is a C 15 -C 20 mixture.