US4536305A — Methods for stabilizing swelling clays or migrati…

Claim 1

Independent Claim 200 words

A method of preventing or reducing the migration of fines or the swelling of clays or combinations thereof in a permeable subterranean formation comprising: contacting said fines or swelling clays or combinations thereof with an effective amount of an organic polycationic polymer having a molecular weight in the range of from about 50,000 to about 300,000 and having monomer units of the formula: ##STR11## wherein R and R 3 are independently an alkylene group having from about 2 to about 4 carbon atoms; R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , and R 9 are independently selected from the group consisting of methyl and ethyl; R 6 is selected from the group consisting of an unsubstituted alkylene group having from about 2 to about 4 carbon atoms and a substituted alkylene group having from about 2 to about 4 carbon atoms and containing a hydroxy group; X is an anion selected from the group consisting of a halogen, methyl sulfate, sulfate, and nitrate; n represents the valency of the anion represented by X; and, a is an integer equal to the number of said anions required to maintain electronic neutrality.

Claim 2

Independent Claim 200 words

A method of preventing or reducing the migration of fines or the swelling of clays or combinations thereof in a permeable subterranean formation comprising: contacting said fines or swelling clays or combinations thereof with an effective amount of an organic polycationic polymer having a molecular weight in the range of from about 50,000 to about 300,000 and having monomer units of the formula: ##STR11## wherein R and R 3 are independently an alkylene group having from about 2 to about 4 carbon atoms; R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , and R 9 are independently selected from the group consisting of methyl and ethyl; R 6 is selected from the group consisting of an unsubstituted alkylene group having from about 2 to about 4 carbon atoms and a substituted alkylene group having from about 2 to about 4 carbon atoms and containing a hydroxy group; X is an anion selected from the group consisting of a halogen, methyl sulfate, sulfate, and nitrate; n represents the valency of the anion represented by X; and, a is an integer equal to the number of said anions required to maintain electronic neutrality.

Claim 3

Dependent Claim 24 words

The method recited in claim 1 wherein R 1 , R 2 , R 7 , R 8 , and R 9 are methyl.

Claim 4

Dependent Claim 24 words

The method recited in claim 2 wherein R and R 3 are independently selected from the group consisting of ethylene, trimethylene, tetramethylene, and 2-methyltrimethylene.

Claim 5

Dependent Claim 20 words

The method recited in claim 3 wherein R 6 is selected from the group consisting of 2-hydroxytrimethylene, 2-hydroxytetramethylene and 3-hydroxytetramethylene.

Claim 6

Dependent Claim 22 words

The method recited in claim 4 wherein X is selected from the group consisting of chloride, bromide, iodide, sulfate and methyl sulfate.

Claim 7

Dependent Claim 20 words

The method recited in claim 5 wherein said organic polycationic polymer has a weight average molecular weight of about 135,000.

Claim 8

Dependent Claim 15 words

The method recited in claim 7 wherein said polymer is dispersed in a carrier fluid.

Claim 9

Dependent Claim 48 words

The method recited in claim 7 wherein said carrier fluid comprises from about 0.1 to about 40.0 percent by weight of a salt and said salt is selected from the group consisting of an alkali metal halide, an alkaline earth metal halide, an ammonium halide, and mixtures thereof.

Claim 10

Dependent Claim 32 words

The method recited in claim 8 wherein said polymer is present in said carrier fluid in the range of from about 0.01 to about 5.0 percent by weight of the carrier fluid.

Claim 11

Dependent Claim 47 words

The method recited in claim 9 wherein said carrier fluid further comprises a mineral acid selected from the group consisting of about 15 percent by weight hydrochloric acid, and a mixture of about 12 percent by weight hydrochloric acid and about 3 percent by weight hydrofluoric acid.

Claim 12

Dependent Claim 18 words

The method recited in claim 1 wherein said method is used in conjunction with a secondary recovery operation.

Claim 13

Dependent Claim 42 words

The method recited in claim 1 wherein R 1 , R 2 , R 7 , R 8 , and R 9 are methyl, R is ethylene, R 4 and R 5 are ethyl, R 6 is 2-hydroxytrimethylene, and X is chloride.

Claim 14

Dependent Claim 26 words

The method recited in claim 12 wherein said fines are selected from the group consisting of silica, iron minerals, alkaline earth metal carbonates and mixtures thereof.

Claim 15

Dependent Claim 55 words

The method recited in claim 1 wherein said polymer further comprises a monomer unit selected from the group consisting of dimethylaminoethyl methacrylate, the alkyl chloride salt of dimethylaminoethyl methacrylate, N,N-dimethylacrylamide, N-Hydroxymethylacrylamide, diethylaminomethyl methacrylate, N,N-dimethylaminopropyl methacrylamide, and mixtures thereof said monomer unit being present in an amount up to 30 percent by weight of the polymer.

Claim 16

Independent Claim 217 words

A method of treating a earthen formation comprising migrating fines or swelling clays or combinations thereof to reduce loss of permeability in said formation because of the migration of said fines or the swelling of said clays or combinations thereof comprising: contacting said fines or swelling clays or combinations thereof with an effective amount of an organic polycationic polymer having a molecular weight in the range of from about 50,000 to about 300,000 and having monomer units of the formula: ##STR12## wherein R and R 3 are independently an alkylene group having from about 2 to about 4 carbon atoms; R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , and R 9 are independently selected from the group consisting of methyl and ethyl; R 6 is selected from the group consisting of an unsubstituted alkylene group having from about 2 to about 4 carbon atoms and a substituted alkylene group having from about 2 to about 4 carbon atoms and containing a hydroxy group; X is an anion selected from the group consisting of a halogen, methyl sulfate, sulfate, and nitrate; n represents the valency of the anion represented by X; and, s is an integer equal to the number of said anions required to maintain electronic neutrality.

Claim 17

Independent Claim 217 words

A method of treating a earthen formation comprising migrating fines or swelling clays or combinations thereof to reduce loss of permeability in said formation because of the migration of said fines or the swelling of said clays or combinations thereof comprising: contacting said fines or swelling clays or combinations thereof with an effective amount of an organic polycationic polymer having a molecular weight in the range of from about 50,000 to about 300,000 and having monomer units of the formula: ##STR12## wherein R and R 3 are independently an alkylene group having from about 2 to about 4 carbon atoms; R 1 , R 2 , R 4 , R 5 , R 7 , R 8 , and R 9 are independently selected from the group consisting of methyl and ethyl; R 6 is selected from the group consisting of an unsubstituted alkylene group having from about 2 to about 4 carbon atoms and a substituted alkylene group having from about 2 to about 4 carbon atoms and containing a hydroxy group; X is an anion selected from the group consisting of a halogen, methyl sulfate, sulfate, and nitrate; n represents the valency of the anion represented by X; and, s is an integer equal to the number of said anions required to maintain electronic neutrality.

Claim 18

Dependent Claim 26 words

The method recited in claim 16 wherein said fines are selected from the group consisting of silica, iron minerals, alkaline earth metal carbonates and mixtures thereof.

Claim 19

Dependent Claim 57 words

The method recited in claim 16 wherein said polymer is dispersed in a carrier fluid and the carrier fluid comprises from about 0.1 to about 40.0 percent by weight of a salt and said salt is selected from the group consisting of an alkali metal halide, an alkaline earth metal halide, an ammonium halide, and mixtures thereof.

Claim 20

Dependent Claim 60 words

The method recited in claim 17 wherein R 1 , R 2 , R 7 , R 8 and R 9 are methyl, R 4 and R 5 are ethyl, R and R 3 are independently selected from the group consisting of ethylene, trimethylene, and tetramethylene, and R 6 is selected from the group consisting of 2-hydroxytrimethylene, 2-hydroxytetramethylene, and 3-hydroxytetramethylene.

Claim 21

Dependent Claim 47 words

The method recited in claim 18 wherein said carrier fluid further comprises a mineral acid selected from the group consisting of about 15 percent by weight hydrochloric acid and a mixture of about 12 percent by weight hydrochloric acid and about 3 percent by weight hydrofluoric acid.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1988-08-19	1989-02-18	1989-08-20	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1992-08-19	1993-02-18	1993-08-20	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1996-08-19	1997-02-18	1997-08-20	$7700.00	Window Closed / Lapsed

Methods for stabilizing swelling clays or migrating fines in subterranean formations

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag