Compositions and Methods for Plugging and Sealing a Subterranean Formation

Abstract

The invention provides for a composition for treating a subterranean formation, the composition comprising a water-swellable agent and a sealing agent. Preferably, the water-swellable agent: i) absorbs greater than 100 weight % of water; and ii) swells to greater than 100 weight % as it absorbs water. Preferably the sealing agent: i) is greater than 0.01 weight % soluble in water; and ii) forms a three dimensional gel structure in water. The invention also provides for a method of treating a subterranean formation penetrated by a wellbore, the method comprising the steps of: a) introducing a sealing agent into the subterranean formation; and b) introducing a water-swellable agent into the subterranean formation.

1 . A composition for treating a subterranean formation, the composition comprising: 
 a water-swellable agent; and    a sealing agent comprising a monomer, wherein the sealing agent is at least about 0.01 weight % soluble in water and is capable of forming a three dimensional gel structure in water.    
   
   
       2 . The composition of  claim 1 , wherein the water-swellable agent comprises at least one water-swellable agent selected from the group consisting of: a crosslinked polyacrylamide; a crosslinked polyacrylate; a copolymer of acrylamide and acrylate monomers; a starch backbone grafted with acrylonitrile and acrylate; a polymer of two or more of allylsulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyloxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and acrylic acid monomers; a hydrolyzed polyacrylonitrile; a carboxyalkyl cellulose; a carboxymethyl starch; a salt of carboxymethyl cellulose; a carboxyalkyl polysaccharide; a crystalline polymer of a crosslinked polyacrylamide; and any combination thereof.  
   
   
       3 . The composition of  claim 1 , wherein the sealing agent comprises: 
 a polymerizable water-soluble vinyl monomer;    a multifunctional vinyl monomer capable of polymerizing and crosslinking; and    a water-soluble azo initiator.    
   
   
       4 . The composition of  claim 1 , wherein the sealing agent comprises: 
 a non-acidic ethylenically unsaturated polar monomer;    a copolymerizable ethylenically unsaturated ester; and    at least one organic gelling agent selected from the group consisting of: a polyalkylenimine; a polyfunctional aliphatic amine; an aralkylamine; a heteroaralkylamine; and any combination thereof.    
   
   
       5 . The composition of  claim 1 , wherein 
 the sealing agent is at least about 0.01 weight % soluble in water; and    the sealing agent is capable of forming a three dimensional gel structure in water.    
   
   
       6 . A composition for treating a subterranean formation, the composition comprising: 
 a water-swellable agent that is capable of absorbing at least about 100 weight % of water and is capable of swelling at least about 100 weight % when it absorbs water; and    a sealing agent comprising a monomer.    
   
   
       7 . The composition of  claim 6 , wherein the water-swellable agent comprises at least one water-swellable agent selected from the group consisting of: a crosslinked polyacrylamide; a crosslinked polyacrylate; a copolymer of acrylamide and acrylate monomers; a starch backbone grafted with acrylonitrile and acrylate; a polymer of two or more of allylsulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyloxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and acrylic acid monomers; a hydrolyzed polyacrylonitrile; a carboxyalkyl cellulose; a carboxymethyl starch; a salt of carboxymethyl cellulose; a carboxyalkyl polysaccharide; a crystalline polymer of a crosslinked polyacrylamide; and any combination thereof.  
   
   
       8 . The composition of  claim 6 , wherein the sealing agent comprises: 
 a polymerizable water-soluble vinyl monomer;    a multifunctional vinyl monomer capable of polymerizing and crosslinking; and    a water-soluble azo initiator.    
   
   
       9 . The composition of  claim 6 , wherein the sealing agent comprises: 
 a non-acidic ethylenically unsaturated polar monomer;    a copolymerizable ethylenically unsaturated ester; and    at least one organic gelling agent selected from the group consisting of: a polyalkylenimine; a polyfunctional aliphatic amine; an aralkylamine; a heteroaralkylamine; and any combination thereof.    
   
   
       10 . The composition of  claim 6 , wherein 
 the sealing agent is at least about 0.01 weight % soluble in water; and    the sealing agent is capable of forming a three dimensional gel structure in water.    
   
   
       11 . A composition for treating a subterranean formation, the composition comprising: 
 a water-swellable agent; and    a sealing agent comprising a monomer.    
   
   
       12 . The composition of  claim 11 , wherein the water-swellable agent comprises at least one water-swellable agent selected from the group consisting of: a crosslinked polyacrylamide; a crosslinked polyacrylate; a copolymer of acrylamide and acrylate monomers; a starch backbone grafted with acrylonitrile and acrylate; a polymer of two or more of allylsulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyloxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and acrylic acid monomers; a hydrolyzed polyacrylonitrile; a carboxyalkyl cellulose; a carboxymethyl starch; a salt of carboxymethyl cellulose; a carboxyalkyl polysaccharide; a crystalline polymer of a crosslinked polyacrylamide; and any combination thereof.  
   
   
       13 . The composition of  claim 11 , wherein the sealing agent comprises: 
 a polymerizable water-soluble vinyl monomer;    a multifunctional vinyl monomer capable of polymerizing and crosslinking; and    a water-soluble azo initiator.    
   
   
       14 . The composition of  claim 11 , wherein the sealing agent comprises: 
 a non-acidic ethylenically unsaturated polar monomer;    a copolymerizable ethylenically unsaturated ester; and    at least one organic gelling agent selected from the group consisting of: a polyalkylenimine; a polyfunctional aliphatic amine; an aralkylamine; a heteroaralkylamine; and any combination thereof.    
   
   
       15 . The composition of  claim 11 , wherein 
 the water-swellable agent is capable of absorbing at least about 100 weight % of water; and    the water-swellable agent is capable of swelling at least about 100 weight % when it absorbs water.    
   
   
       16 . The composition of  claim 11 , wherein 
 the sealing agent is at least about 0.01 weight % soluble in water; and    the sealing agent is capable of forming a three dimensional gel structure in water.    
   
   
       17 . A composition for treating a subterranean formation, the composition comprising: 
 a water-swellable agent comprising at least one water-swellable agent selected from the group consisting of: a crosslinked polyacrylamide; a crosslinked polyacrylate; a copolymer of acrylamide and acrylate monomers; a starch backbone grafted with acrylonitrile and acrylate; a polymer of two or more of allylsulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyloxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and acrylic acid monomers; a hydrolyzed polyacrylonitrile; a carboxyalkyl cellulose; a carboxymethyl starch; a salt of carboxymethyl cellulose; a carboxyalkyl polysaccharide; a crystalline polymer of a crosslinked polyacrylamide; and any combination thereof; and    a sealing agent comprising a monomer.    
   
   
       18 . The composition of  claim 17 , wherein the sealing agent comprises: 
 a polymerizable water-soluble vinyl monomer;    a multifunctional vinyl monomer capable of polymerizing and crosslinking; and    a water-soluble azo initiator.    
   
   
       19 . The composition of  claim 17 , wherein the sealing agent comprises: 
 a non-acidic ethylenically unsaturated polar monomer;    a copolymerizable ethylenically unsaturated ester; and    at least one organic gelling agent selected from the group consisting of: a polyalkylenimine; a polyfunctional aliphatic amine; an aralkylamine; a heteroaralkylamine; and any combination thereof.    
   
   
       20 . The composition of  claim 17 , wherein 
 the water-swellable agent is capable of absorbing at least about 100 weight % of water; and    the water-swellable agent is capable of swelling at least about 100 weight % when it absorbs water.    
   
   
       21 . The composition of  claim 17 , wherein 
 the sealing agent is at least about 0.01 weight % soluble in water; and    the sealing agent is capable of forming a three dimensional gel structure in water.    
   
   
       22 . A composition for treating a subterranean formation, the composition comprising: 
 a water-swellable agent; and    a sealing agent comprising: 
 a non-acidic ethylenically unsaturated polar monomer;  
 a copolymerizable ethylenically unsaturated ester; and  
 at least one organic gelling agent selected from the group consisting of: a polyalkylenimine; a polyfunctional aliphatic amine; an aralkylamine; a heteroaralkylamine; and any combination thereof.  
   
   
   
       23 . The composition of  claim 22 , wherein the water-swellable agent comprises at least one water-swellable agent selected from the group consisting of: a crosslinked polyacrylamide; a crosslinked polyacrylate; a copolymer of acrylamide and acrylate monomers; a starch backbone grafted with acrylonitrile and acrylate; a polymer of two or more of allylsulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyloxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and acrylic acid monomers; a hydrolyzed polyacrylonitrile; a carboxyalkyl cellulose; a carboxymethyl starch; a salt of carboxymethyl cellulose; a carboxyalkyl polysaccharide; a crystalline polymer of a crosslinked polyacrylamide; and any combination thereof.  
   
   
       24 . The composition of  claim 22 , wherein 
 the water-swellable agent is capable of absorbing at least about 100 weight % of water; and    the water-swellable agent is capable of swelling at least about 100 weight % when it absorbs water.    
   
   
       25 . The composition of  claim 22 , wherein 
 the sealing agent is at least about 0.01 weight % soluble in water; and    the sealing agent is capable of forming a three dimensional gel structure in water.