# US 2019/0161671 A1 · Methods and Thermally Stable Aqueous Borate-Based Cross-Linking Suspensions for Treatment of Subterranean Formations > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0161671 A1 - Document ID: US20190161671A1 - Status: Published application - Kind: A1 - Application number: 16/092,739 - Filed: 2017-04-10 - Published: 2019-05-30 - Earliest claimed: 2016-04-14 - Assignees: Univar USA Inc. - Applicants: Univar USA Inc. - Inventors: Abdelaziz Rahy; DeWitt Knox; Mohand Melbouci - Web page: https://patentgrep.com/patent/US20190161671A1 ## CPC - C09K 8/685: {containing cross-linking agents} - C08K 3/011: Crosslinking or vulcanising agents, e.g. accelerators - C09K 8/68: containing organic compounds - C09K 8/887: {containing cross-linking agents} - C09K 8/90: of natural origin, e.g. polysaccharides, cellulose - E21B 43/26: by forming crevices or fractures - C08K 2003/387: {Borates} - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract An aqueous cross-linking suspension composition having brine, water-soluble suspending agent and borate cross-linker in a single package and methods for using the package composition for increasing the efficiency of fracturing subterranean formations and effectively delivering borate cross-linkers. ## Claims ### Claim 1 An aqueous cross-linking suspension composition comprising: a) water; b) 20-70 weight percent of brine; c) 0.1-5 weight percent of water-soluble suspending agent; and d) 20-70 weight percent of borate cross-linker. ### Claim 2 (depends on 1) The aqueous cross-linking suspension composition of claim 1 wherein said brine is selected from the group consisting of sodium thiosulfate, potassium thiosulfate, magnesium thiosulfate, calcium thiosulfate and ammonium thiosulfate. ### Claim 3 (depends on 1) The aqueous cross-linking suspension composition of claim 1 wherein said borate cross-linker is selected from the group consisting of ulexite, borax, boric acid and combinations thereof. ### Claim 4 (depends on 1) The suspension composition of claim 1 wherein said brine is sodium thiosulfate and said borate cross-linker is ulexite. ### Claim 5 (depends on 1) The suspension composition of claim 1 further comprising 0.1-5 weight percent boric acid. ### Claim 6 (depends on 1) The suspension composition of claim 1 wherein said water-soluble suspending agent is selected from the group consisting of synthetic polymer, biopolymer, cellulose ether and combinations thereof. ### Claim 7 (depends on 6) The suspension composition of claim 6 wherein said synthetic polymer is selected from the group consisting of: polyvinyl alcohol, polyacrylate, polyacrylamide, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylamide copolymer, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylic acid copolymer, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylamide/acrylic acid terpolymer and combinations thereof. ### Claim 8 (depends on 6) The suspension composition of claim 6 wherein said biopolymer is selected from the group consisting of: xanthan gum, diutan gum, wellan gum, schleroglucane gum and combinations thereof. ### Claim 9 (depends on 6) The suspension composition of claim 6 wherein said cellulose ether is selected from the group consisting of: carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, methyl hydroxyethyl cellulose, hydroxypropyl cellulose and combinations thereof. ### Claim 10 (depends on 7) The suspension composition of claim 7 wherein said synthetic polymer is polyvinyl alcohol. ### Claim 11 A method for fracturing a subterranean formation having a downhole temperature ranging from about 65° F. to about 350° F. with a fracturing fluid containing a gellant comprising the steps of: a) preparing an aqueous cross-linking suspension composition of 20-70 weight percent sodium thiosulfate, 0.1-5 weight percent of water-soluble suspending agent and 20-70 weight percent ulexite; b) treating a fracturing fluid containing said gellant with said aqueous cross-linking suspension composition to form a treated gellant-containing fracturing fluid; and then c) contacting the treated gellant-containing fracturing fluid and at least a portion of said subterranean formation at pressures sufficient to form fractures in said formation, wherein thermal stability of said fracturing fluid containing gellant is enhanced. ### Claim 12 (depends on 11) The method of claim 11, wherein said downhole temperature ranges from about 65° F. to about 350° F. ### Claim 13 (depends on 11) The method of claim 11 wherein said water-soluble suspending agent is selected from the group consisting of synthetic polymer, biopolymer, cellulose ether and combinations thereof. ### Claim 14 (depends on 13) The method of claim 13 wherein said synthetic polymer is selected from the group consisting of: polyvinyl alcohol, polyacrylate, polyacrylamide, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylamide copolymer, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylic acid copolymer, 2-acrylamido-2-methyl-1-propane sulfonic acid/acrylamide/acrylic acid terpolymer and combinations thereof. ### Claim 15 (depends on 14) The method of claim 14 wherein said cellulose ether is selected from the group consisting of: carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, methyl hydroxyethyl cellulose, hydroxypropyl cellulose and combinations thereof. ### Claim 16 (depends on 13) The method of claim 13 wherein said synthetic polymer is polyvinyl alcohol. ### Claim 17 (depends on 16) The method of claim 16 wherein said aqueous cross-linking suspension further comprises 0.1-5 weight percent boric acid. ### Claim 18 (depends on 11) The method of claim 11 wherein said gellant is guar. ### Claim 19 A method for efficiently delivering borate-based cross-linkers for fracturing a subterranean formation having a downhole temperature ranging from about 65° F. to about 350° F. with a fracturing fluid containing a gellant comprising the steps of: a) preparing an aqueous cross-linking suspension package comprising 20-70 weight percent sodium thiosulfate, 0.1-5 weight percent of water-soluble suspending agent and 20-70 weight percent ulexite; b) treating a fracturing fluid containing said gallant with said aqueous cross-linking suspension package to form a treated gellant-containing fracturing fluid; and then c) contacting the treated gellant-containing fracturing fluid and at least a portion of said subterranean formation at pressures sufficient to form fractures in said formation.