Methods and compositions for improving hydrocarbon recovery by water flood intervention

Abstract

Methods useful in improving hydrocarbon recovery from subterranean formations using relative permeability modifier (RPM) macromolecules are described. The RPMs are typically crosslinked RPMs having K-values from 250-300 which, when injected into an injector well associated with a producer well, redirect the production water so as to improve the injection profile of the well and simultaneously improve hydrocarbon recovery from the producer well.

1 . A method for increasing hydrocarbon production from a production well in a hydrocarbon-bearing formation, wherein there is at least one injector well associated with the production well, the method comprising: 
 introducing an aqueous treating composition comprising a relative permeability modifier (RPM) macromolecule into one or more injector wells.    
     
     
         2 . The method of  claim 1 , wherein the relative permeability modifier macromolecule is a microgel.  
     
     
         3 . The method of  claim 2 , wherein the microgel has a weight average molecular weight from about 10 4  to about 10 8  g/mol.  
     
     
         4 . The method of  claim 2 , wherein the microgel is present in the aqueous concentrate composition in a concentration of about 15,000 parts per million (ppm) to about 50,000 ppm.  
     
     
         5 . The method of  claim 2 , wherein the microgel has a K value from about 200 to about 1,000.  
     
     
         6 . The method of  claim 5 , wherein the microgel has a K value from about 250 to about 300.  
     
     
         7 . The method of  claim 1 , wherein the relative permeability modifier macromolecule has a viscosity from about 1 cP to about 5 cP.  
     
     
         8 . The method of  claim 1 , wherein the relative permeability modifier macromolecule is deformable.  
     
     
         9 . The method of  claim 1 , wherein the concentration of the relative permeability modifier in the aqueous treating composition introduced into the one or more injector wells is from about 3 ppm to about 6000 ppm.  
     
     
         10 . The method of  claim 1 , wherein the aqueous treating composition further comprises water, brine, or seawater.  
     
     
         11 . The method of  claim 1 , wherein the relative permeability modifier macromolecule is capable of redirecting a portion of the water flow through the hydrocarbon-bearing formation from the injector well(s) to the producer well.  
     
     
         12 . The method of  claim 1 , further comprising the step of providing an improved injection profile after the introducing step.  
     
     
         13 . A method for increasing hydrocarbon production from a production well in a hydrocarbon-bearing formation, wherein there is at least one injector well associated with the production well, the method comprising: 
 introducing an aqueous treating composition comprising a relative permeability modifier (RPM) macromolecule into an injector well in a permeable formation, in an amount effective to enhance oil production from the production well; and    continuing the injection of the RPM macromolecule into the injector well for a time sufficient to increase oil flow from the formation to the production well where it is subsequently produced to the surface via the producer well.    
     
     
         14 . The method of  claim 13 , wherein the RPM macromolecule is capable of redirecting water flow through the hydrocarbon-bearing formation to provide an improved injection profile.  
     
     
         15 . The method of  claim 13 , further comprising the step of forming a treating solution comprising at least one relative permeability modifier (RPM) macromolecule in an aqueous solution prior to, or during the introducing step.  
     
     
         16 . The method of  claim 15 , wherein the solution has a RPM macromolecule concentration from about 3 ppm to about 6000 ppm.  
     
     
         17 . The method of  claim 15 , wherein the forming of a treating solution step is carried out at the wellsite, immediately prior to, or during, the introducing step.  
     
     
         18 . The method of  claim 13 , wherein the relative permeability modifier has a weight average molecular weight from about 10,000 to about 50,000,000 g/mol.  
     
     
         19 . The method of  claim 18 , wherein the relative permeability modifier has a weight average molecular weight from about 50,000 to about 5,000,000 g/mol.  
     
     
         20 . The method of  claim 19 , wherein the relative permeability modifier macromolecule has a weight average molecular weight from about 100,000 to about 2,000,000 g/mol.  
     
     
         21 . The method of  claim 13 , wherein the relative permeability modifier macromolecule has a K value from about 200 to about 1000.  
     
     
         22 . The method of  claim 21 , wherein the relative permeability modifier macromolecule has a K value from about 200 to about 600.  
     
     
         23 . The method of  claim 1 , wherein the relative permeability modifier macromolecule comprises a homopolymer, a terpolymer, or copolymer of acrylamide.  
     
     
         24 . The method of  claim 1 , wherein the relative permeability modifier macromolecule comprises a quaternary ammonium salt, sulfonic acid salt, or mixture thereof.  
     
     
         25 . The method of  claim 1 , wherein the aqueous treating composition comprises a relative permeability modifier macromolecule and an organosilicon compound capable of forming a reactive silanol.  
     
     
         26 . The method of  claim 1 , wherein the relative permeability modifier macromolecule is crosslinked.  
     
     
         27 . The method of  claim 1 , wherein the hydrocarbon-bearing formation is a permeable formation comprised of diatomaceous materials, quartz, shale, zeolite, chert, clay, silt, carbonate, or combinations thereof.  
     
     
         28 . The method of  claim 23 , wherein the RPM is crosslinked.  
     
     
         29 . The method of  claim 13 , further comprising the step of injecting an external crosslinker into the hydrocarbon-bearing formation.  
     
     
         30 . The method of  claim 9 , wherein the relative permeability modifier macromolecule is present in the aqueous treating composition in an amount from about 10 ppm to about 3,000 ppm.  
     
     
         31 . The method of  claim 26 , wherein the crosslinked RPM macromolecule comprises: 
 a terpolymer, copolymer or homopolymer comprising an anchoring monomer and a hydrophilic monomer;    wherein the anchoring monomer is a vinyl formamide or a mixture thereof, and the hydrophilic monomer is an acrylamido sulfonic acid or a mixture thereof; and    wherein the RPM macromolecule is capable of redirecting water flow through the hydrocarbon-bearing formation to provide an improved injection profile.    
     
     
         32 . The method of  claim 26 , wherein the crosslinked RPM macromolecule is deformable.  
     
     
         33 . The method of  claim 1 , wherein the aqueous treating solution is introduced at flow rates below flow rates necessary to cause fractures in the subterranean formation.  
     
     
         34 . The method of  claim 26 , wherein the RPM macromolecule is crosslinked either during polymerization or by an external crosslinker during the introduction step.  
     
     
         35 . The method of  claim 26 , wherein the crosslinked RPM macromolecule further comprises an acrylamide spacer monomer.  
     
     
         36 . The method of  claim 26 , further comprising: 
 preparing an aqueous solution of an anchoring monomer, a hydrophilic monomer, and a spacer monomer; and    polymerizing the monomers in the aqueous solution to form a RPM macromolecule; wherein the preparing and polymerizing take place prior to the injection step;    wherein the anchoring monomer is a vinylformamide;    wherein the hydrophilic monomer is an alkali metal, alkali earth metal, or quaternary ammonium salt of an acrylamido sulfonic acid; and    wherein the spacer monomer is an acrylamide or mixture of acrylamides.    
     
     
         37 . The method of  claim 36 , wherein the preparing and polymerizing steps are carried out at or near the wellbore.  
     
     
         38 . The method of  claim 36 , wherein the polymerization step further comprises a crosslinking step to form a crosslinked RPM macromolecule, the crosslinking step comprising: 
 contacting the RPM macromolecule with a crosslinking agent selected from the group consisting of aldehydes, amides, metal salts, epoxides, carbodiimides, di- or poly-allyl based monomers, or mixtures thereof.    
     
     
         39 . A method for increasing hydrocarbon production from a production well in a hydrocarbon-bearing formation, wherein there is at least one injector well associated with the production well, the method comprising: 
 introducing an aqueous water-control fluid composition comprising a relative permeability modifier (RPM) macromolecule and an aqueous base fluid into an injector well in a permeable formation; and    continuing the injection of the RPM macromolecule into the injector well for a time sufficient to increase oil flow from the formation to the production well where it is subsequently produced to the surface via the producer well;    wherein the RPM macromolecule is capable of redirecting water flow through the hydrocarbon-bearing formation to provide an improved injection profile; and    wherein the water control fluid composition is introduced into the hydrocarbon-bearing formation prior to, in conjunction with, or after a stimulation operation into the formation.    
     
     
         40 . The method of  claim 39 , wherein the RPM macromolecule is crosslinked.  
     
     
         41 . A method for enhancing hydrocarbon recovery from a reservoir or formation containing substantially immobile hydrocarbons, the method comprising: 
 a) drilling and completing at least one injector well in a subterranean formation in proximity to a producer well, or converting a producer well into an injector well in proximity to other producer wells;    b) directing an aqueous mixture comprising a relative permeability modifier (RPM) macromolecule into the injector well, wherein the RPM macromolecule is present in an amount effective to redirect water flow in the subterranean formation and thereby increase hydrocarbon flow therefrom; and    c) continuing the injection of the aqueous mixture comprising a RPM macromolecule into the injector well for a time sufficient to increase flow of hydrocarbons from the formation towards the producer well, where it is subsequently produced to the surface via the producer well.    
     
     
         42 . The method of  claim 41 , further comprising, after step (c): 
 injecting the aqueous mixture into the at least one injector well,    aqueous mixture injection is ceased, and hydrocarbons are produced from the producer well.    
     
     
         43 . The method of  claim 41 , wherein the RPM macromolecule is crosslinked.