Methods, Systems, and Compositions for the Controlled Crosslinking of Well Servicing Fluids

Abstract

Treating fluid compositions for use in hydrocarbon recovery operations from subterranean formations are described, as well as methods for their preparation and use. In particular, treating fluid compositions are described which comprise a liquid, a crosslinkable organic polymer material that is at least partially soluble in the liquid, a crosslinking agent that is capable of increasing the viscosity of the treating fluid by crosslinking the organic polymer material in the liquid, and a crosslinking modifier additive which can delay or accelerate the crosslinking of the treating fluid composition. Such compositions may be used in a variety of hydrocarbon recovery operations including fracturing operations, drilling operations, gravel packing operations, water control operations, and the like.

What is claimed is: 
     
         1 . A method of treating a subterranean formation, the method comprising:
 generating a treating fluid by mixing an aqueous base fluid comprising a crosslinkable organic polymer with a crosslinking additive capable of crosslinking the crosslinkable organic polymer at a controlled crosslinking rate, and   delivering the treating fluid into a subterranean formation; wherein   the crosslinking additive comprises a crosslinking agent selected from the group consisting of ulexite, colemanite, probertite, and mixtures thereof premixed with one or more salt-based crosslinking modifiers in an aqueous fluid, wherein the amount of the one or more salt-based crosslinking modifiers is determined to provide the controlled crosslinking rate, wherein   the one or more salt-based crosslinking modifiers are selected from the group consisting of alkali metal inorganic salts, alkaline earth metal inorganic salts, alkali metal carbonates, organic amine salts, ammonium salts, benzoate salts, borate salts, citrate salts, fumarate salts, halide salts, and lactate salts.   
     
     
         2 . The method of  claim 1 , further comprising delivering an inorganic or organic peroxide breaker into the subterranean formation. 
     
     
         3 . The method of  claim 2 , wherein the inorganic or organic peroxide breaker is slightly soluble in water. 
     
     
         4 . The method of  claim 1 , wherein the crosslinking additive comprises a freeze-point depressant. 
     
     
         5 . The method of  claim 1 , wherein the crosslinking additive further comprises a suspension agent selected from the group consisting of clays, polymers, and combinations thereof. 
     
     
         6 . The method of  claim 5 , wherein the suspension agent is selected from the group consisting of palygorskite-type clays consisting of attapulgite, smectite, sepiolite, and composite mixtures thereof. 
     
     
         7 . The method of  claim 5 , wherein the suspension agent is a water-soluble polymer selected from the group consisting of biopolymers, naturally-occurring polymers, derivatives thereof, and combinations thereof. 
     
     
         8 . The method of  claim 1 , wherein the crosslinking additive comprises a deflocculant. 
     
     
         9 . The method of  claim 1 , wherein the crosslinking additive comprises one or more chelating agents. 
     
     
         10 . The method of  claim 1 , wherein the crosslinking additive comprises a friction reducer. 
     
     
         11 . The method of  claim 1 , wherein the crosslinking modifier has aconcentration of about 0.01 to about 80 percent by weight. 
     
     
         12 . A composition for crosslinking aqueous, crosslinkable organic polymer solutions at a controlled crosslinking rate, the composition comprising:
 a crosslinking agent premixed with one or more salt-based crosslinking modifiers in an aqueous fluid, wherein   the amount of the one or more salt-based crosslinking modifiers is determined to provide the controlled crosslinking rate, wherein   the crosslinking agent is selected from the group consisting of ulexite, colemanite, probertite, and mixtures thereof and wherein   the one or more salt-based crosslinking modifiers are selected from the group consisting of alkali metal inorganic salts, alkaline earth metal inorganic salts, alkali metal carbonates, organic amine salts, ammonium salts, benzoate salts, borate salts, citrate salts, fumarate salts, halide salts, and lactate salts.   
     
     
         13 . The method of  claim 12 , wherein the crosslinkable organic polymer is a polysaccharide. 
     
     
         14 . The method of  claim 13 , wherein the polysaccharide is guar, cellulose, starch, galactomannan gum, xanthan, succinoglycan or scleroglucan or a derivative thereof. 
     
     
         15 . The method of  claim 14 , wherein the polysaccharide is selected from the group consisting of guar, hydroxypropyl guar, carboxymethylhydroxypropyl guar, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl cellulose, hydroxyethylmethyl cellulose, hydroxypropylmethyl cellulose, hydroxybutylmethyl cellulose, methylhydroxyethyl cellulose, methylhydroxypropyl cellulose, ethylhydroxyethyl cellulose, carboxyethylcellulose, carboxymethylcellulose or carboxymethylhydroxyethyl cellulose. 
     
     
         16 . The composition of  claim 12 , wherein the crosslinking agent has a concentration of about 0.1 kg/m 3  to about 5 kg/m 3 . 
     
     
         17 . The composition of  claim 12 , wherein the composition further comprises a suspension agent selected from the group consisting of clays, polymers, and combinations thereof. 
     
     
         18 . The composition of  claim 17 , wherein the suspension agent is selected from the group consisting of palygorskite-type clays consisting of attapulgite, smectite, sepiolite, and composite mixtures thereof. 
     
     
         19 . The composition of  claim 17 , wherein the suspension agent is a water-soluble polymer selected from the group consisting of biopolymers, naturally-occurring polymers, derivatives thereof, and combinations thereof. 
     
     
         20 . The composition of  claim 12 , wherein the composition further comprises a freeze-point depressant. 
     
     
         21 . The composition of  claim 12 , wherein the composition further comprises a deflocculant. 
     
     
         22 . The composition of  claim 12 , wherein the composition further comprises one or more chelating agents. 
     
     
         23 . The composition of  claim 12 , wherein the composition further comprises a friction reducer. 
     
     
         24 . The composition of  claim 12 , wherein the crosslinking modifier has a concentration of about 0.01 to about 80 percent by weight. 
     
     
         25 . A composition for crosslinking aqueous, crosslinkable organic polymer solutions at a controlled crosslinking rate, wherein the composition is prepared by a process comprising:
 mixing a crosslinking agent and one or more salt-based crosslinking modifiers in an aqueous fluid, wherein   the amount of the one or more salt-based crosslinking modifiers is determined to provide the controlled crosslinking rate, wherein   the crosslinking agent is selected from the group consisting of ulexite, colemanite, probertite, and mixtures thereof, and wherein   the one or more salt-based crosslinking modifiers are selected from the group consisting of alkali metal inorganic salts, alkaline earth metal inorganic salts, alkali metal carbonates, organic amine salts, ammonium salts, benzoate salts, borate salts, citrate salts, fumarate salts, halide salts, and lactate salts.   
     
     
         26 . The composition of  claim 25 , wherein the crosslinking modifier_has a concentration of about 0.01 to about 80 percent by weight.