Compositions and Methods for Hindering Asphaltene Deposition

Abstract

Methods and compositions for hindering asphaltene deposition. One method comprising: identifying an interval of the subterranean formation to be treated with a relative permeability modifier to hinder subsequent asphaltene deposition; introducing the relative permeability modifier into the subterranean formation; and allowing the relative permeability modifier to contact the interval, thereby attaching to surfaces within the subterranean formation and hindering subsequent asphaltene deposition.

1 . A method of hindering asphaltene deposition comprising:
 identifying an interval of the subterranean formation to be treated with a relative permeability modifier to hinder subsequent asphaltene deposition;   introducing the relative permeability modifier into the subterranean formation; and   allowing the relative permeability modifier to contact the interval, thereby attaching to surfaces within the subterranean formation and hindering subsequent asphaltene deposition.   
   
   
       2 . The method of  claim 1  wherein the relative permeability modifier comprises a water-soluble hydrophobically modified polymer. 
   
   
       3 . The method of  claim 2  wherein the hydrophobically modified polymer comprises a hydrophilic polymer backbone and a hydrophobic branch, the hydrophobic branch comprising about 7 to about 22 carbons. 
   
   
       4 . The method of  claim 2  wherein the hydrophobically modified polymer comprises an alkyl group present on an amino group in quaternized form. 
   
   
       5 . The method of  claim 2  wherein the hydrophobically modified polymer comprises polydimethylaminoethylmethacrylate or polydimetylaminopropylmethacrylamide that has been hydrophobically modified with an alkyl group of about 12 to about 22 carbons. 
   
   
       6 . A method of removing asphaltenes and hindering subsequent asphaltene deposition in a subterranean formation comprising:
 introducing a fluid comprising a relative permeability modifier and an asphaltene solvent system into the subterranean formation; and   allowing the fluid to contact a portion of the subterranean formation, wherein the asphaltene solvent system removes at least a portion of an asphaltene on the portion of the subterranean formation, and wherein the relative permeability modifier hinders subsequent asphaltene deposition on the portion of the subterranean formation.   
   
   
       7 . The method of  claim 6  comprising identifying an interval of the subterranean formation to be treated with the relative permeability modifier to hinder subsequent asphaltene deposition 
   
   
       8 . The method of  claim 6  wherein the relative permeability modifier comprises a water-soluble hydrophobically modified polymer. 
   
   
       9 . The method of  claim 8  wherein the hydrophobically modified polymer comprises a hydrophilic polymer backbone and a hydrophobic branch, the hydrophobic branch comprising about 7 to about 22 carbons. 
   
   
       10 . The method of  claim 8  wherein the hydrophobically modified polymer comprises an alkyl group present on an amino group in quaternized form. 
   
   
       11 . The method of  claim 8  wherein the hydrophobically modified polymer comprises polydimethylaminoethylmethacrylate or polydimetylaminopropylmethacrylamide that has been hydrophobically modified with an alkyl group of about 12 to about 22 carbons. 
   
   
       12 . The method of  claim 6  wherein asphaltene solvent system comprises water, an organic solvent, a surfactant. 
   
   
       13 . The method of  claim 12  wherein the organic solvent comprises at least one non-polar organic solvent selected from the group consisting of an aromatic solvent, a terpene, kerosene, diesel, xylene, toluene, cyclohexanone, D-limonene, and dipentene 
   
   
       14 . The method of  claim 12  wherein the organic solvent comprises at least one polar organic solvent selected from the group consisting of N-methyl pyrrolidone and cyclohexanone. 
   
   
       15 . The method of  claim 6  wherein the asphaltene solvent system comprises at least two polar organic solvents, wherein one of the polar organic solvents has a Snyder polarity index in the range of about 3 to about 5, and wherein another of the polar organic solvents has a Snyder polarity index in the range of about 5 to about 7. 
   
   
       16 . A method of removing asphaltenes and hindering subsequent asphaltene deposition in a subterranean formation comprising:
 introducing a permeability modifying fluid into a well bore that penetrates a subterranean formation, wherein the permeability modifying fluid comprises a relative permeability modifier;   allowing at least a portion of the permeability modifying fluid to penetrate into a portion of the subterranean formation so that the relative permeability modifier present in the portion of the subterranean formation substantially diverts subsequently introduced aqueous fluids to less permeable portions of the subterranean formation, wherein the relative permeability modifier in the portion of the subterranean formation hinders subsequent asphaltene deposition; and   introducing an asphaltene solvent system into the well bore to remove asphaltenes on the subterranean formation, wherein the relative permeability modifier present in the portion of the subterranean formation diverts the asphaltene solvent system to a less permeable portion of the subterranean formation.   
   
   
       17 . The method of  claim 16  comprising identifying an interval of the subterranean formation to be treated with the permeability modifying fluid to hinder subsequent asphaltene deposition 
   
   
       18 . The method of  claim 16  wherein the relative permeability modifier comprises a water-soluble hydrophobically modified polymer. 
   
   
       19 . The method of  claim 18  wherein the hydrophobically modified polymer comprises a hydrophilic polymer backbone and a hydrophobic branch, the hydrophobic branch comprising about 7 to about 22 carbons. 
   
   
       20 . The method of  claim 18  wherein the hydrophobically modified polymer comprises an alkyl group present on an amino group in quaternized form. 
   
   
       21 . The method of  claim 18  wherein the hydrophobically modified polymer comprises polydimethylaminoethylmethacrylate or polydimetylaminopropylmethacrylamide that has been hydrophobically modified with an alkyl group of about 12 to about 22 carbons. 
   
   
       22 . The method of  claim 16  wherein asphaltene solvent system comprises water, an organic solvent, a surfactant. 
   
   
       23 . The method of  claim 22  wherein the organic solvent comprises at least one non-polar organic solvent selected from the group consisting of an aromatic solvent, a terpene, kerosene, diesel, xylene, toluene, cyclohexanone, D-limonene, and dipentene 
   
   
       24 . The method of  claim 22  wherein the organic solvent comprises at least one polar organic solvent selected from the group consisting of N-methyl pyrrolidone and cyclohexanone. 
   
   
       25 . The method of  claim 16  wherein the asphaltene solvent system comprises at least two polar organic solvents, wherein one of the polar organic solvents has a Snyder polarity index in the range of about 3 to about 5, and wherein another of the polar organic solvents has a Snyder polarity index in the range of about 5 to about 7.