US4231882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treating subterranean well formations
Assignee: Halliburton Co
•
Filing: 1978-10-20
•
Granted: 1980-11-04
•
Expires: 1998-10-20
Abstract
Abstract A method of treating a subterranean well formation wherein a low pH highly viscous thixotropic treating fluid is introduced into the formation. The treating fluid is formed by combining an aqueous acid solution with an aqueous alkali metal silicate solution and a gelling agent whereby a highly viscous polymerized alkali metal silicate gel of low pH is produced followed by shearing of the gel to impart thixotropic properties thereto.
Inventors
- 👤 Eugene A. Elphingstone
- 👤 Lewis R. Norman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:08
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/66; C09K8/665; C09K8/72; C09K8/74; Y; Y10; Y10S; Y10S516/00; Y10S516/924
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
253 words
A method of forming a low pH highly viscous thixotropic fluid for use in treating a subterranean well formation comprising the steps of: combining an aqueous solution of acid other than hydrofluoric acid with an aqueous alkali metal silicate solution having a pH of greater than about 11 in an amount sufficient to lower the pH of the resulting mixture to the level in the range of from about 7.5 to about 8.5 thereby forming a polymerized alkali metal silicate gel; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR3## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range or from about 8 to about 22 carbon atoms, and x and y each have a value in the range of from 0 to about 10 but both x and y are not 0; and said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; combining additional aqueous solution of acid other than hydrofluoric acid with said polymerized alkali metal silicate gel-gelling agent mixture in an amount sufficient to obtain a mixture containing excess acid in the range of from about 1% to about 28% by weight of said mixture; and shearing said mixture to thereby obtain a highly viscous thixotropic treating fluid.
Claim 2
Independent Claim
253 words
A method of forming a low pH highly viscous thixotropic fluid for use in treating a subterranean well formation comprising the steps of: combining an aqueous solution of acid other than hydrofluoric acid with an aqueous alkali metal silicate solution having a pH of greater than about 11 in an amount sufficient to lower the pH of the resulting mixture to the level in the range of from about 7.5 to about 8.5 thereby forming a polymerized alkali metal silicate gel; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR3## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range or from about 8 to about 22 carbon atoms, and x and y each have a value in the range of from 0 to about 10 but both x and y are not 0; and said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; combining additional aqueous solution of acid other than hydrofluoric acid with said polymerized alkali metal silicate gel-gelling agent mixture in an amount sufficient to obtain a mixture containing excess acid in the range of from about 1% to about 28% by weight of said mixture; and shearing said mixture to thereby obtain a highly viscous thixotropic treating fluid.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein the average sum of the values of x and y in said mixture is in the range of from about 1.8 to about 2.2.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein said alkali metal silicate is sodium silicate.
Claim 5
Dependent Claim
20 words
The method of claim 1 wherein said aqueous sodium silicate solution is Grade 40 sodium silicate solution diluted with water.
Claim 6
Dependent Claim
24 words
The method of claim 3 wherein said acid is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid and mixtures thereof.
Claim 7
Dependent Claim
11 words
The method of claim 5 wherein said acid is hydrochloric acid.
Claim 8
Dependent Claim
59 words
The method of claim 1 wherein R is selected from the group consisting of saturated and unsaturated aliphatic groups having in the range of from about 14 to about 18 carbon atoms and mixtures of such groups, and wherein the average sum of the values of x and y in said mixture of ethoxylated amines is equal to 2.
Claim 9
Dependent Claim
13 words
The method of claim 7 wherein said organic solvent is an organic acid.
Claim 10
Dependent Claim
12 words
The method of claim 8 wherein said organic acid is acetic acid.
Claim 11
Dependent Claim
39 words
The method of claim 7 wherein said organic solvent in said gelling agent is acetic acid and said ethoxylated fatty amines are present in said gelling agent in an amount of about 50% by weight of said gelling agent.
Claim 12
Dependent Claim
42 words
The method of claim 1 wherein said gelling agent includes an ethoxylated fatty amine having the general formula: ##STR4## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms.
Claim 13
Dependent Claim
43 words
The method of claim 1 wherein said mixture of additional aqueous solution of acid other than hydrofluoric acid and said polymerized alkali metal silicate gel-gelling agent mixture contains excess acid in the range of from about 1% to about 5% of said mixture.
Claim 14
Independent Claim
240 words
A method of forming a low pH highly viscous thixotropic fluid for use in treating a subterranean well formation comprising the steps of: combining an aqueous alkali metal silicate solution having a pH greater than about 11 with an aqueous solution of acid other than hydrofluoric acid in a quantity whereby excess acid is present in the resulting mixture in an amount in the range of from about 1% by weight to about 28% by weight and whereby a polymerized alkali metal silicate gel is formed therein; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR5## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixture being in the range of from about 1.8 to about 2.2; said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; and shearing said polymerized alkali metal silicate gel-gelling agent mixture to thereby obtain a highly viscous thixotropic acidic treating fluid.
Claim 15
Independent Claim
240 words
A method of forming a low pH highly viscous thixotropic fluid for use in treating a subterranean well formation comprising the steps of: combining an aqueous alkali metal silicate solution having a pH greater than about 11 with an aqueous solution of acid other than hydrofluoric acid in a quantity whereby excess acid is present in the resulting mixture in an amount in the range of from about 1% by weight to about 28% by weight and whereby a polymerized alkali metal silicate gel is formed therein; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR5## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixture being in the range of from about 1.8 to about 2.2; said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; and shearing said polymerized alkali metal silicate gel-gelling agent mixture to thereby obtain a highly viscous thixotropic acidic treating fluid.
Claim 16
Dependent Claim
13 words
The method of claim 13 wherein said alkali metal silicate is sodium silicate.
Claim 17
Dependent Claim
20 words
The method of claim 13 wherein said aqueous sodium silicate solution is Grade 40 sodium silicate solution diluted with water.
Claim 18
Dependent Claim
24 words
The method of claim 14 wherein said acid is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid and mixtures thereof.
Claim 19
Dependent Claim
11 words
The method of claim 16 wherein said acid is hydrochloric acid.
Claim 20
Dependent Claim
59 words
The method of claim 13 wherein R is selected from the group consisting of saturated and unsaturated aliphatic groups having in the range of from about 14 to about 18 carbon atoms and mixtures of such groups, and wherein the average sum of the values of x and y in said mixture of ethoxylated amines is equal to 2.
Claim 21
Dependent Claim
13 words
The method of claim 18 wherein said organic solvent is an organic acid.
Claim 22
Dependent Claim
12 words
The method of claim 19 wherein said organic acid is acetic acid.
Claim 23
Dependent Claim
39 words
The method of claim 18 wherein said organic solvent in said gelling agent is acetic acid and said ethoxylated fatty amines are present in said gelling agent in an amount of about 50% by weight of said gelling agent.
Claim 24
Dependent Claim
42 words
The method of claim 13 wherein said gelling agent includes an ethoxylated fatty amine having the general formula: ##STR6## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms.
Claim 25
Independent Claim
284 words
A method of fracturing and simultaneously acidizing a subterranean well formation comprising the steps of: combining an aqueous solution of acid other than hydrofluoric acid with an aqueous alkali metal silicate solution having a pH of greater than about 11 in an amount sufficient to lower the pH of the resulting mixture to a level in the range of from about 7.5 to about 8.5 thereby forming a polymerized alkali metal silicate gel; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR7## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixture being in the range of from about 1.8 to about 2.2; said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; combining additional aqueous solution of acid other than hydrofluoric acid with said polymerized alkali metal silicate gel-gelling agent mixture in an amount sufficient to obtain a mixture containing excess acid in the range of about 1% to about 28% by weight of said mixture; shearing said mixture to thereby obtain a highly viscous thoxitropic acidic treating fluid; and introducing said treating fluid into said subterranean formation at a flow rate and pressure sufficient to produce a fracture therein.
Claim 26
Independent Claim
284 words
A method of fracturing and simultaneously acidizing a subterranean well formation comprising the steps of: combining an aqueous solution of acid other than hydrofluoric acid with an aqueous alkali metal silicate solution having a pH of greater than about 11 in an amount sufficient to lower the pH of the resulting mixture to a level in the range of from about 7.5 to about 8.5 thereby forming a polymerized alkali metal silicate gel; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR7## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixture being in the range of from about 1.8 to about 2.2; said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; combining additional aqueous solution of acid other than hydrofluoric acid with said polymerized alkali metal silicate gel-gelling agent mixture in an amount sufficient to obtain a mixture containing excess acid in the range of about 1% to about 28% by weight of said mixture; shearing said mixture to thereby obtain a highly viscous thoxitropic acidic treating fluid; and introducing said treating fluid into said subterranean formation at a flow rate and pressure sufficient to produce a fracture therein.
Claim 27
Dependent Claim
20 words
The method of claim 23 wherein said aqueous alkali metal silicate solution is Grade 40 sodium silicate diluted with water.
Claim 28
Dependent Claim
11 words
The method of claim 24 wherein said acid is hydrochloric acid.
Claim 29
Dependent Claim
59 words
The method of claim 23 wherein R is selected from the group consisting of saturated and unsaturated aliphatic groups having in the range of from about 14 to about 18 carbon atoms and mixtures of such groups, and wherein the average sum of the values of x and y in said mixture of ethoxylated amines is equal to 2.
Claim 30
Dependent Claim
39 words
The method of claim 26 wherein said organic solvent in said gelling agent is acetic acid and said ethoxylated fatty amines are present in said gelling agent in an amount of about 50% by weight of said gelling agent.
Claim 31
Dependent Claim
30 words
The method of claim 27 which is further characterized to include the step of combining a propping agent with said mixture prior to introducing said mixture into said subterranean formation.
Claim 32
Dependent Claim
43 words
The method of claim 23 wherein said mixture of additional aqueous solution of acid other than hydrofluoric acid and said polymerized alkali metal silicate gel-gelling agent mixture contains excess acid in the range of from about 1% to about 5% of said mixture.
Claim 33
Independent Claim
257 words
A method of fracturing and simultaneously acidizing a subterranean well formation comprising the steps of: combining an aqueous alkali metal silicate solution having a pH of greater than about 11 with an aqueous solution of acid other than hydrofluoric acid in a quantity whereby excess acid is present in the resulting mixture in an amount in the range of from about 1% by weight to about 28% by weight of said mixture and whereby a polymerized alkali metal silicate gel is formed therein; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR8## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixtures being in the range of from about 1.8 to about 2.2; and said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; shearing said polymerized alkali metal silicate gel-gelling agent mixture to thereby obtain a highly viscous thixotropic acidic treating fluid; and introducing said treating fluid into said subterranean formation at a flow rate and pressure sufficient to produce a fracture therein.
Claim 34
Independent Claim
257 words
A method of fracturing and simultaneously acidizing a subterranean well formation comprising the steps of: combining an aqueous alkali metal silicate solution having a pH of greater than about 11 with an aqueous solution of acid other than hydrofluoric acid in a quantity whereby excess acid is present in the resulting mixture in an amount in the range of from about 1% by weight to about 28% by weight of said mixture and whereby a polymerized alkali metal silicate gel is formed therein; combining a gelling agent with said polymerized alkali metal silicate gel, said gelling agent consisting of a solution of a water soluble organic solvent and a mixture of ethoxylated fatty amines having the general formula: ##STR8## wherein: R is selected from saturated and unsaturated aliphatic groups having in the range of from about 8 to about 22 carbon atoms and mixtures thereof, and x and y each have a value in the range of from 0 to about 10 with the average sum of the values of x and y in said mixtures being in the range of from about 1.8 to about 2.2; and said ethoxylated fatty amine is present in said gelling agent in an amount in the range of from about 10% to about 80% by weight of said gelling agent; shearing said polymerized alkali metal silicate gel-gelling agent mixture to thereby obtain a highly viscous thixotropic acidic treating fluid; and introducing said treating fluid into said subterranean formation at a flow rate and pressure sufficient to produce a fracture therein.
Claim 35
Dependent Claim
20 words
The method of claim 30 wherein said aqueous alkali metal silicate solution of Grade 40 sodium silicate diluted with water.
Claim 36
Dependent Claim
11 words
The method of claim 31 wherein said acid is hydrochloric acid.
Claim 37
Dependent Claim
59 words
The method of claim 30 wherein R is selected from the group consisting of saturated and unsaturated aliphatic groups having in the range of from about 14 to about 18 carbon atoms and mixtures of such groups, and wherein the average sum of the values of x and y in said mixture of ethoxylated amines is equal to 2.
Claim 38
Dependent Claim
39 words
The method of claim 33 wherein said organic solvent in said gelling agent is acetic acid and said ethoxylated fatty amines are present in said gelling agent in an amount of about 50% by weight of said gelling agent.
Claim 39
Dependent Claim
30 words
The method of claim 34 which is further characterized to include the step of combining a propping agent with said mixture prior to introducing said mixture into said subterranean formation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-04 | 1984-05-05 | 1984-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-04 | 1988-05-05 | 1988-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-04 | 1992-05-05 | 1992-11-04 | $7700.00 | Window Closed / Lapsed |