Clean Viscosified Treatment Fluids and Associated Methods

Abstract

The present invention relates to low environmental impact treatment fluids comprising a compliant crosslinking agent, and methods of use employing such treatment fluids to treat subterranean formations. The methods include providing a low environmental impact treatment fluid including an aqueous base fluid, a viscosifying agent, and a compliant crosslinking agent that comprises an iron ion and a non-iron crosslinking metal ion; and placing the treatment fluid in a subterranean formation. In some embodiments, the viscosifying agent may be a compliant viscosifying agent.

1 . A method comprising:
 providing a low environmental impact treatment fluid comprising an aqueous base fluid, a viscosifying agent, and a compliant crosslinking agent that comprises an iron ion and a non-iron crosslinking metal ion; and   placing the treatment fluid in a subterranean formation.   
     
     
         2 . The method of  claim 1  wherein the non-iron crosslinking metal ion is selected from the group consisting of: a titanium ion, an aluminum ion, a chromium(III) ion, a copper ion, a zinc ion, a zirconium ion, a magnesium ion, and any combination thereof. 
     
     
         3 . The method of  claim 1  wherein the non-iron crosslinking metal ion is an aluminum ion. 
     
     
         4 . The method of  claim 1  wherein the viscosifying agent is selected from the group consisting of a polysaccharide, a cellulose, a starch, a gelatin, an acrylamide, an acrylate, and any combination thereof. 
     
     
         5 . The method of  claim 1  wherein the viscosifying agent is a compound selected from the group consisting of: a carboxymethylguar, a carboxymethylhydroxyethylguar, a carboxymethylhydroxypropylguar, a hydroxyethylcellulose, a carboxyethylcellulose, a carboxymethylcellulose, a carboxymethylhydroxyethylcellulose, a diutan gum, a xanthan gum, a galactomannan, a hydroxyethylguar, a hydroxypropylguar, a scleroglucan, a wellan, a native starch, a modified starch, a cook-up starch, a pre-gelatinized starch, a chitosan, an alginate, a carrageenan, and any derivative and combination thereof. 
     
     
         6 . The method of  claim 1  wherein the compliant viscosifying agent comprises a polysaccharide and a starch. 
     
     
         7 . The method of  claim 1  wherein the compliant viscosifying agent comprises a compliant cellulosic viscosifying agent and a polysaccharide. 
     
     
         8 . The method of  claim 1  wherein the subterranean formation comprises a bottom hole temperature of up to and including about 275° F. 
     
     
         9 . The method of  claim 1  wherein the viscosifying agent is a compliant viscosifying agent selected from the group consisting of carboxyethylcellulose, carboxymethylcellulose, carboxymethylhydroxyethylcellulose, and any derivative and combination thereof. 
     
     
         10 . The method of  claim 1  wherein the treatment fluid further comprises an encapsulated breaker. 
     
     
         11 . The method of  claim 1  wherein the treatment fluid further comprises a compliant dual-functional additive selected from the group consisting of ethyl formate, propyl formate, butyl formate, amyl formate, anisyl formate, methyl acetate, propyl acetate, triacetin, butyl propionate, isoamyl propionate, ethyl lactate, methyl butyrate, ethyl isobutyrate, butyl isobutyrate, diethyl malonate, butyl ethyl malonate, dimethyl succinate, diethyl succinate, diethyl malate, diethyl tartrate, dimethyl tartrate, triethyl citrate, and any derivative and combination thereof. 
     
     
         12 . The method of  claim 1  wherein the treatment fluid is placed in the subterranean formation as part of a subterranean operation selected from the group consisting of a drilling operation, a fracturing operation, a completion operation, and a workover operation. 
     
     
         13 . The method of  claim 1  wherein the treatment fluid comprises a viscosifying agent comprising carboxymethylcellulose and a compliant crosslinking agent that comprises an iron ion and an aluminum ion; and further comprises:
 a surfactant comprising sodium lauryl sulfate and polyoxyethylene (20) sorbitan monolaurate. 
 
     
     
         14 . The method of  claim 13  wherein the treatment fluid further comprises an encapsulated citric acid breaker, a compliant dual-functional additive comprising triethyl citrate or a combination thereof. 
     
     
         15 . A method comprising:
 providing a low environmental impact treatment fluid comprising:
 an aqueous base fluid, 
 a compliant viscosifying agent, 
 a compliant crosslinking agent that comprises an iron ion and a non-iron crosslinking metal ion, 
 a compliant dual-functional additive; and 
   placing the treatment fluid in a subterranean formation.   
     
     
         16 . The method of  claim 10  wherein the compliant viscosifying agent is selected from the group consisting of a polysaccharide, a cellulose, a gelatin, an acrylamide, an acrylate, and any combination thereof. 
     
     
         17 . The method of  claim 10  wherein the compliant viscosifying agent comprises a blend of a first compliant viscosifying agent and a second compliant viscosifying agent. 
     
     
         18 . The method of  claim 12  wherein the first compliant viscosifying agent is a cellulose derivative selected from the group consisting of: a carboxymethylguar, a carboxymethylhydroxyethylguar, a carboxymethylhydroxypropylguar, a hydroxyethylcellulose, a carboxyethylcellulose, a carboxymethylcellulose, a carboxymethylhydroxyethylcellulose, and any derivative and combination thereof. 
     
     
         19 . The method of  claim 12  wherein the second compliant viscosifying agent is a polysaccharide selected from the group consisting of: a diutan gum, a xanthan gum, a galactomannan, a hydroxyethylguar, a hydroxypropylguar, a scleroglucan, a wellan, a native starch, a modified starch, a cook-up starch, a pre-gelatinized starch, a chitosan, an alginate, a carrageenan, and any derivative and combination thereof. 
     
     
         20 . The method of  claim 10  wherein the compliant crosslinking agent comprises a non-iron crosslinking metal ion selected from the group consisting of: a titanium ion, an aluminum ion, a chromium(III) ion, a copper ion, a zinc ion, a zirconium ion, a magnesium ion, and any combination thereof. 
     
     
         21 . The method of  claim 10  wherein the subterranean formation comprises a bottom hole temperature of up to and including about 275° F. 
     
     
         22 . The method of  claim 10  wherein the treatment fluid is placed in the subterranean formation as part of a subterranean operation selected from the group consisting of a drilling operation, a fracturing operation, a completion operation, and a workover operation. 
     
     
         23 . The method of  claim 10  wherein the compliant dual-functional additive is a liquid selected from the group consisting of: ethyl formate, propyl formate, butyl formate, amyl formate, anisyl formate, methyl acetate, propyl acetate, triacetin, butyl propionate, isoamyl propionate, ethyl lactate, methyl butyrate, ethyl isobutyrate, butyl isobutyrate, diethyl malonate, butyl ethyl malonate, dimethyl succinate, diethyl succinate, diethyl malate, diethyl tartrate, dimethyl tartrate, triethyl citrate, and any combination thereof. 
     
     
         24 . The method of  claim 10  wherein the treatment fluid further comprises an encapsulated breaker. 
     
     
         25 . A method comprising:
 providing a providing a low environmental impact fracturing fluid comprising an aqueous base fluid a compliant viscosifying agent, and a compliant crosslinking agent that comprises an iron ion and a non-iron crosslinking metal ion; and   introducing the fracturing fluid into at least a portion of a subterranean formation at a rate and pressure sufficient to create or enhance at least one or more fractures in the subterranean formation.