Cross-linked acrylamide polymer or copolymer gel and breaker compositions and methods of use

Abstract

Well treatment fluids, and methods for treating wellbores or fracturing subterranean formations, which include acrylamide polymer or copolymer crosslinked with one or more crosslinkers and one or more iron-containing compounds are provided. The fluids and methods may be used to carry proppants into fractures and to increase fluid recovery in hydraulic fracturing applications

1 - 2 . (canceled) 
     
     
         3 . A well treatment fluid comprising:
 (i) a gel composition comprising an acrylamide polymer or copolymer;   (ii) one or more crosslinkers; and   (iii) a breaker composition comprising one or more iron-containing compounds and one or more booster compounds selected from the group consisting of ethylenediaminetetraacetic acid (EDTA); salts of EDTA; citric acid; aminotricarboxylic acid and its salts; ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1, 1-diphosphonic acid and aminotri(methylene phosphonic acid) and their salts; boric acid and its salts; alkali metal salts of carbonates; diethylenetriaminepentaacetic acid (DTPA); and lignosulfates.   
     
     
         4 . The well treatment fluid of  claim 3 , wherein the gel composition is formed by combining the monomers of the acrylamide polymer or copolymer and the one or more crosslinkers in an aqueous solution at a pH in the range of about 5 to about 12, and wherein the molar ratio of the one or more crosslinkers to monomers of the acrylamide polymer or copolymer is in the range of about greater than about 0.1 to about 2.0. 
     
     
         5 - 8 . (canceled) 
     
     
         9 . A method of treating a wellbore comprising:
 injecting into the wellbore:
 (i) a first composition comprising monomers of an acrylamide polymer or copolymer, or an aqueous dispersion or emulsion of an acrylamide polymer or copolymer; 
 (ii) a second composition comprising one or more crosslinkers; and 
 (iii) a breaker composition comprising one or more iron-containing compounds and one or more booster compounds selected from the group consisting of ethylenediaminetetraacetic acid (EDTA); salts of EDTA; citric acid; aminotricarboxylic acid and its salts; ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1, 1-diphosphonic acid and aminotri(methylene phosphonic acid) and their salts; boric acid and its salts; alkali metal salts of carbonates; diethylenetriaminepentaacetic acid (DTPA); 
   and lignosulfates.   
     
     
         10 . (canceled) 
     
     
         11 . The method of  claim 9 , wherein the breaker composition is injected into the wellbore substantially at the same time as the first and second compositions. 
     
     
         12 . The method of  claim 9 , wherein the breaker composition is injected into the wellbore after the first and second compositions. 
     
     
         13 . A method of treating a wellbore comprising:
 injecting into a wellbore a gel composition comprising an acrylamide polymer or copolymer, one or more crosslinkers, and a breaker composition comprising one or more iron-containing compounds and one or more booster compounds selected from the group consisting of ethylenediaminetetraacetic acid (EDTA); salts of EDTA; citric acid; aminotricarboxylic acid and its salts; ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1, 1-diphosphonic acid and aminotri(methylene phosphonic acid) and their salts; boric acid and its salts; alkali metal salts of carbonates; diethylenetriaminepentaacetic acid (DTPA); and lignosulfates.   
     
     
         14 . The method of  claim 13 , wherein the gel composition is formed by combining the monomers of the acrylamide polymer or copolymer and the one or more crosslinkers in an aqueous solution at a pH in the range of about 5 to about 12, and wherein the molar ratio of the one or more crosslinkers to monomers of the acrylamide polymer or copolymer is in the range of about greater than about 0.1 to about 2.0. 
     
     
         15 . The method of  claim 13 , wherein the breaker composition is injected into the wellbore substantially at the same time as the gel composition. 
     
     
         16 . The method of  claim 13 , wherein the breaker composition is injected into the wellbore after the gel composition. 
     
     
         17 . A method of fracturing a subterranean formation comprising:
 providing:
 (i) a first composition comprising monomers of an acrylamide polymer or copolymer, or an aqueous dispersion or emulsion of an acrylamide polymer or copolymer; 
 (ii) a second composition comprising one or more crosslinkers; and 
 (iii) a breaker composition comprising one or more iron-containing compounds and one or more booster compounds selected from the group consisting of ethylenediaminetetraacetic acid (EDTA); salts of EDTA; citric acid; aminotricarboxylic acid and its salts; ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1, 1-diphosphonic acid and aminotri(methylene phosphonic acid) and their salts; boric acid and its salts; alkali metal salts of carbonates; diethylenetriaminepentaacetic acid (DTPA); and lignosulfates; and 
   placing the compositions into a subterranean formation so as to create or enhance a fracture in the subterranean formation.   
     
     
         18 . (canceled) 
     
     
         19 . A method of fracturing a subterranean formation comprising:
 providing:
 (i) a gel composition comprising an acrylamide polymer or copolymer; 
 (ii) one or more crosslinkers; and 
 (iii) a breaker composition comprising one or more iron-containing compounds and one or more booster compounds selected from the group consisting of ethylenediaminetetraacetic acid (EDTA); salts of EDTA; citric acid; aminotricarboxylic acid and its salts; ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyethylidene-1, 1-diphosphonic acid and aminotri(methylene phosphonic acid) and their salts; boric acid and its salts; alkali metal salts of carbonates; diethylenetriaminepentaacetic acid (DTPA); and lignosulfates; and 
   placing the compositions into a subterranean formation so as to create or enhance a fracture in the subterranean formation.   
     
     
         20 . The method of  claim 19 , wherein the gel composition is formed by combining the monomers of the acrylamide polymer or copolymer and the one or more crosslinkers in an aqueous solution at a pH in the range of about 5 to about 12, and wherein the molar ratio of the one or more crosslinkers to monomers of the acrylamide polymer or copolymer is in the range of about greater than about 0.1 to about 2.0. 
     
     
         21 . (canceled) 
     
     
         22 . The well treatment fluid of  claim 3 , wherein the gel composition is in the form of monomers of an acrylamide polymer or copolymer, and wherein the one or more crosslinkers crosslink the monomers of the acrylamide polymer or copolymer. 
     
     
         23 . The well treatment fluid of  claim 22 , wherein the one or more iron-containing compounds is selected from the group consisting of a ferrous compound, a ferrous salt, a ferric compound and a ferric salt. 
     
     
         24 . The well treatment fluid of  claim 22 , wherein the one or more iron-containing compounds is selected from the group consisting of ferrous chloride, ferrous bromide, ferrous fluoride, ferrous sulfate, ammonium iron sulfate, and combinations thereof. 
     
     
         25 . The well treatment fluid of  claim 22 , wherein the one or more crosslinkers are selected from the group consisting of compounds comprising zirconium, titanium, chromium, barium, calcium manganese, zinc, nickel, strontium, boron, and mixtures thereof. 
     
     
         26 . The well treatment fluid of  claim 22 , wherein the one or more crosslinkers are selected from the group consisting of glyoxal, malondialdehyde, succindialdehyde, glutaraldehyde, adipaldehyde, o-phthaldehyde, m-phthaldehyde, p-phthaldehyde, polyethylene imine, phenol/formaldehyde, glyoxlic acid, and mixtures thereof. 
     
     
         27 . The well treatment fluid of  claim 3 , wherein the gel composition is in the form of an aqueous dispersion or emulsion of an acrylamide polymer or copolymer. 
     
     
         28 . The well treatment fluid of  claim 27 , wherein the one or more water-soluble iron-containing compounds is selected from the group consisting of a ferrous compound, a ferrous salt, a ferric compound, and a ferric salt. 
     
     
         29 . The well treatment fluid of  claim 27 , wherein the one or more water-soluble iron-containing compounds is selected from the group consisting of ferrous chloride, ferrous bromide, ferrous fluoride, ferrous sulfate, ferrous citrate, ammonium iron sulfate, and combinations thereof. 
     
     
         30 . The well treatment fluid of  claim 27 , wherein the one or more crosslinkers are selected from the group consisting of compounds comprising zirconium, titanium, chromium, barium, calcium, manganese, zinc, nickel, strontium, boron, and mixtures thereof. 
     
     
         31 . The well treatment fluid of  claim 27 , wherein the one or more crosslinkers are selected from the group consisting of glyoxal, malondialdehyde, succindialdehyde, glutaraldehyde, adipaldehyde, o-phthaldehyde, m-phthaldehyde, p-phthaldehyde, polyethylene imine, phenol/formaldehyde, glyoxlic acid, and mixtures thereof.