Ampholyte polymeric compounds in subterranean applications

Patent metadata

Field	Value
Publication number	US-9816022-B2
Application number	US-201313929835-A
Country	US
Kind code	B2
Filing date	Jun 28, 2013
Priority date	May 31, 2013
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

Ampholyte polymeric compound that comprises at least one nonionic monomer, at least one sulfonic acid-containing monomer, and at least one cationic monomer may be useful in viscosifying treatment fluids for use in subterranean operations at a concentration of about 0.5 v/v % to about 30 v/v % of the treatment fluid. Such operations may involve introducing the treatment fluid into a wellbore penetrating a subterranean formation optionally at a pressure sufficient to create or extend at least one fracture in the subterranean formation.

First claim

The invention claimed is:

1. A method comprising:
introducing a treatment fluid into a wellbore penetrating a subterranean formation,
wherein the treatment fluid comprises a base fluid and an ampholyte polymeric compound,
wherein the ampholyte polymeric compound comprises:
30-50% by weight of at least one nonionic monomer, wherein the nonionic monomer is acrylamide,
5-15% by weight of at least one sulfonic acid-containing monomer, wherein the sulfonic acid-containing monomer is 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof, and
40-60% by weight of at least one cationic monomer, wherein the cationic acid-containing monomer is acryloyloxy ethyl trimethyl ammonium chloride, methacrylamidopropyltrimethyl ammonium chloride, or a combination thereof, and

wherein the ampholyte polymeric compound is present at about 1 v/v % to about 30 v/v % of the treatment fluid,
wherein the treatment fluid comprises 100,000 to 250,000 ppm of total dissolved solids, and

reducing the viscosity of the treatment fluid from 35-155 cP to less than 5 cP in 90 minutes or less, wherein the treatment fluid contains no, or less than about 1% of a, chemical breaker.

2. The method of claim 1 further comprising:
partially hydrolyzing the ampholyte polymeric compound.

3. The method of claim 1 , wherein the treatment fluid further comprises a plurality of particulates.

4. The method of claim 3 further comprising:
forming a gravel pack comprising the particulates in an annulus within the wellbore.

5. A method comprising:
introducing a treatment fluid into a wellbore penetrating a subterranean formation at a pressure sufficient to create or extend at least one fracture in the subterranean formation,
wherein the treatment fluid comprises a first base fluid and a first ampholyte polymeric compound,
wherein the ampholyte polymeric compound comprises:
30-50% by weight of at least one nonionic monomer, wherein the nonionic monomer is acrylamide,
5-15% by weight of at least one sulfonic acid-containing monomer, wherein the sulfonic acid-containing monomer is 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof, and
40-60% by weight of at least one cationic monomer, wherein the cationic acid-containing monomer is acryloyloxy ethyl trimethyl ammonium chloride, methacrylamidopropyltrimethyl ammonium chloride, or a combination thereof, and

wherein the ampholyte polymeric compound is present at about 2.5 v/v % to about 30 v/v % of the treatment fluid,
wherein the treatment fluid comprises 100,000 to 250,000 ppm of total dissolved solids, and

reducing the viscosity of the treatment fluid from at least 35 cP to less than 5 cP in 90 minutes or less, wherein the treatment fluid contains no, or less than about 1% of a, chemical breaker.

6. The method of claim 5 further comprising:
forming a particulate pack in the fracture with a second treatment fluid that comprises a second base fluid, a second ampholyte polymeric compound at a friction reducing concentration, a gas, a foaming agent, and a plurality of particulates.

7. The method of claim 6 , wherein the second base fluid is the same as the first base fluid and the second ampholyte polymeric compound is the same as the first ampholyte polymeric compound.

8. A method comprising:
introducing a treatment fluid into a wellbore penetrating a subterranean formation, wherein the treatment fluid comprises a base fluid having from 100,000 to 250,000 ppm of total dissolved solids, and an ampholyte polymeric compound at about 5 v/v % to about 30 v/v % of the treatment fluid, the ampholyte polymeric compound comprising:
acrylamide monomer that is about 30% to about 50% by weight of the ampholyte polymeric compound,
2-acrylamido-2-methylpropane sulfonic acid monomer or a salt thereof that is about 5% to about 15% by weight of the ampholyte polymeric compound, and
acryloyloxy ethyl trimethyl ammonium chloride monomer that is about 40% to about 60% by weight of the ampholyte polymeric compound, and

reducing the viscosity of the treatment fluid from at least 35 cP to less than 5 cP in 90 minutes or less, wherein the treatment fluid contains no, or less than about 1% of a, chemical breaker.

Assignees

• Halliburton Energy Services Inc

Inventors

• Chung Hsinchen
• Hu Yuntao Thomas
• Ye Xiangnan
• Tonmukayakul Narongsak
• Mccabe Michael A
• Frederick Kevin Walter
• Chen Shih-Ruey Tom
• Loeffler Randy Jack

Classifications

• E21B43/27

  by use of eroding chemicals, e.g. acids · CPC title

• E21B43/26

  by forming crevices or fractures · CPC title

• C09K8/68 Primary

  containing organic compounds · CPC title

• C09K8/725

  Compositions containing polymers · CPC title

• C09K8/36

  Water-in-oil emulsions · CPC title