Preflush chemicals for scale inhibitor squeeze

Abstract

A method and system for removing water from the near wellbore during scale inhibitor squeeze treatments.

1 . A preflush solution for injection into a wellbore before a scale inhibitor squeeze treatment, said preflush solution comprising at least 90% petroleum miscible fluid, at least 1% alkyl polyglycoside (APG) at least 0.5% ethoxylated alcohol (AE) or alcohol ethoxysulfates (AES), and at least 1% linear alcohol, wherein said preflush solution forms a Windsor Type III or Type IV microemulsion with water. 
     
     
         2 . The preflush solution of  claim 1 , wherein said APG are C8-C16, said EA or EAS are C8-C15 with an average of about 2-14 ethylene oxide groups, and said alcohols are about C4-C15. 
     
     
         3 . The preflush solution of  claim 1 , wherein said alkyl polyglycosides are C10-C14 alkyl polyglucosides, said ethoxylated alcohols are C9-C15 with an average of about 12 ethylene oxide groups, and said alcohols are about C6-C12. 
     
     
         4 . The preflush solution of  claim 1 , comprising 94.28% diesel, 2.51% GLUCOPON 600 CSUP , 1.09% TOMADOL 91-2.5, 0.12% TOMADOL 25-12, 1% n-hexanol, and 1% n-octanol. 
     
     
         5 . The preflush solution of  claim 1 , comprising 94.28% Diesel, 2.51% GLUCOPON 600 CSUP; 1.21% TOMADOL 91-2.5, 1.5% n-butanol and 0.5% n-hexanol. 
     
     
         6 . The preflush solution of  claim 1 , comprising 92% C8-C14 hydrocarbons; 3% GLUCOPON 600 UP; 1% TOMADOL 91-2.5; 2% n-butanol; and 1% n-hexanol. 
     
     
         7 . The preflush solution of  claim 1 , comprising 95% C10-C14 hydrocarbons; 2% TRITON CG-600; 2% TERGITOL® 15-S-3 ; 0.5% n-butanol and 0.5%; n-hexanol. 
     
     
         8 . A preflush solution for injection into a wellbore before a scale inhibitor squeeze treatment, said preflush solution comprising at least 90% diesel, at least 1% APG at least 0.5% EA, and at least 1% alcohol, wherein said preflush solution forms a Windsor Type III or Type IV microemulsion with water and crude in place. 
     
     
         9 . The preflush solution of  claim 8 , wherein said alkyl polyglycosides are C10-C14 alkyl polyglucosides, said ethoxylated alcohols are C9-C15 with an average of about 12 ethylene oxide groups, and said alcohols are about C6-C12. 
     
     
         10 . The preflush solution of  claim 8 , comprising 94.28% diesel, 2.51% GLUCOPON 600 CSUP , 1.09% TOMADOL 91-2.5, 0.12% TOMADOL 25-12, 1% n-hexanol, and 1% n-octanol. 
     
     
         11 . The preflush solution of  claim 8 , comprising 94.28% Diesel, 2.51% GLUCOPON 600 CSUP; 1.21% TOMADOL 91-2.5, 1.5% n-butanol and 0.5% n-hexanol. 
     
     
         12 . The preflush solution of  claim 8 , comprising 92% C8-C14 hydrocarbons; 3% GLUCOPON 600 UP; 1% TOMADOL 91-2.5; 2% n-butanol; and 1% n-hexanol. 
     
     
         13 . The preflush solution of  claim 8 , comprising 95% C10-C14 hydrocarbons; 2% TRITON CG-600; 2% TERGITOL® 15-S-3 ; 0.5% n-butanol and 0.5%; n-hexanol. 
     
     
         14 . A preflush solution for injection into a wellbore before a scale inhibitor squeeze treatment, said preflush solution comprising at least 90% C8-C14 hydrocarbons, 1-5% APG, 0.5-5% EA, and 0.5-5% linear alcohol wherein said preflush solution forms a Windsor Type III or Type IV microemulsion with water and crude in place. 
     
     
         15 . The preflush solution of  claim 14 , wherein said alkyl polyglycosides are C10-C14 alkyl polyglucosides, said ethoxylated alcohols are C9-C15 with an average of about 12 ethylene oxide groups, and said alcohols are about C6-C12. 
     
     
         16 . The preflush solution of  claim 14 , comprising 94.28% diesel, 2.51% GLUCOPON 600 CSUP , 1.09% TOMADOL 91-2.5, 0.12% TOMADOL 25-12, 1% n-hexanol, and 1% n-octanol. 
     
     
         17 . The preflush solution of  claim 14 , comprising 92% C8-C14 hydrocarbons; 3% GLUCOPON 600 UP; 1% TOMADOL 91-2.5; 2% n-butanol; and 1% n-hexanol. 
     
     
         18 . The preflush solution of  claim 14 , comprising 95% C10-C14 hydrocarbons; 2% TRITON CG-600; 2% TERGITOL® 15-S-3 ; 0.5% n-butanol and 0.5%; n-hexanol. 
     
     
         19 . The preflush solution of  claim 14 , wherein said APG are C8-C16, said EA or EAS are C8-C15 with an average of about 2-14 ethylene oxide groups, and said alcohols are about C4-C15. 
     
     
         20 . An improved method of scale inhibitor squeeze treatment, said treatment comprising injecting a scale inhibitor into a wellbore, injecting a push solution into said wellbore, shutting said well in for a period of time, and opening said well for flowback of said injected fluids and production of oil, the improvement comprising injecting a preflush solution into said wellbore before injecting a scale inhibitor into said wellbore wherein said preflush solution comprising at least 90% petroleum miscible fluid, at least 1% alkyl polyglycoside (APG) at least 0.5% ethoxylated alcohol (AE) or alcohol ethoxysulfates (AES), and at least 1% linear alcohol, wherein said preflush solution forms a Windsor Type III or Type IV microemulsion with water. 
     
     
         21 . The method of  claim 20 , wherein said alkyl polyglycosides are C10-C14 alkyl polyglucosides, said ethoxylated alcohols are C9-C15 with an average of about 12 ethylene oxide groups, and said alcohols are about C6-C12. 
     
     
         22 . The method of  claim 20 , wherein said preflush solution comprises 94.28% diesel, 2.51% GLUCOPON 600 CSUP , 1.09% TOMADOL 91-2.5, 0.12% TOMADOL 25-12, 1% n-hexanol, and 1% n-octanol. 
     
     
         23 . The method of  claim 20 , wherein said preflush solution comprises 92% C8-C14 hydrocarbons; 3% GLUCOPON 600 UP; 1% TOMADOL 91-2.5; 2% n-butanol; and 1% n-hexanol. 
     
     
         24 . The method of  claim 20 , wherein said preflush solution comprises 95% C10-C14 hydrocarbons; 2% TRITON CG-600; 2% TERGITOL® 15-S-3 ; 0.5% n-butanol and 0.5%; n-hexanol. 
     
     
         25 . The method of  claim 20 , wherein said preflush solution comprises said APG are C8-C16, said EA or EAS are C8-C15 with an average of about 2-14 ethylene oxide groups, and said alcohols are about C4-C15. 
     
     
         26 . A scale inhibitor squeeze method for minimizing scaling in a reservoir, comprising:
 a) injecting the preflush solution into a wellbore in a reservoir;   b) injecting a scale inhibitor fluid into said wellbore;   c) injecting a push fluid to push the injected scale inhibitor fluid into the reservoir surrounding said wellbore;   d) shutting in said wellbore for a period of time;   e) opening said wellbore for back flow of said push fluid and said scale inhibitor fluid and lastly for backflow of said preflush solution; and   f) producing a hydrocarbon reservoir fluid from said wellbore   wherein said preflush solution comprising at least 90% petroleum miscible fluid, at least 1% alkyl polyglycoside (APG) at least 0.5% ethoxylated alcohol (AE) or alcohol ethoxysulfates (AES), and at least 1% linear alcohol, wherein said preflush solution forms a Windsor Type III or Type IV microemulsion with water.   
     
     
         27 . The method of  claim 26 , wherein said preflush fluid penetrates at least 0.5-5 feet into said reservoir. 
     
     
         28 . The method of  claim 26 , wherein said preflush fluid penetrates at least 0.5-8 feet into said reservoir. 
     
     
         29 . The method of  claim 26 , wherein said push fluid comprises brine or hydrocarbon. 
     
     
         30 . The method of  claim 26 , wherein said push fluid comprises said preflush solution. 
     
     
         31 . The method of  claim 26 , wherein said preflush solution forms a Type III or Type IV microemulsion with any water left behind from said backflowed push fluid and said scale inhibitor fluid, thus removing said water on backflow of said microemulsion. 
     
     
         32 . The method of  claim 26 , wherein the rate of production of said hydrocarbon reservoir fluid is at least as good after said method as it was before said method. 
     
     
         33 . The method of  claim 26 , wherein the rate of production of said hydrocarbon reservoir fluid is improved after said method over what it was before said method.