# US 2019/0169489 A1 · Formulations comprising recovered water and a viscosifier, and associated methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0169489 A1 - Document ID: US20190169489A1 - Status: Published application - Kind: A1 - Application number: 16/323,416 - Filed: 2017-07-13 - Published: 2019-06-06 - Earliest claimed: 2016-08-05 - Assignees: Independence Oilfield Chemicals LLC - Applicants: Independence Oilfield Chemicals LLC - Inventors: Christopher George Burke; Chen Xiyuan; John R Willingham; Matthew Kye Yocham; Jeffrey c. Dawson - Web page: https://patentgrep.com/patent/US20190169489A1 ## CPC - C09K 8/685: {containing cross-linking agents} - C09K 8/528: inorganic depositions, e.g. sulfates or carbonates - C09K 8/665: {containing inorganic compounds (proppants C09K8/80)} - C09K 8/845: {containing inorganic compounds} - C09K 8/887: {containing cross-linking agents} - C09K 8/90: of natural origin, e.g. polysaccharides, cellulose - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract High viscosity fracturing fluids for fracturing a subterranean formulation are prepared by: (i) selecting recovered water; (ii) contacting said recovered water with a viscosifying agent, wherein said viscosifying agent is selected from fenugreek gum, tara gum, locust bean gum, guar gum and derivatives of the aforesaid; (iii) contacting said recovered water with one or more other additives for example with a cross-linking agent (A) for cross-linking said viscosifying agent, wherein contact of said recovered water with cross-linking agent (A) takes place when the pH of said recovered water is less than pH 6.5; (iv) adjusting the pH to pH 6.5-8.8. ## Claims ### Claim 1 A method of preparing a fracturing fluid for fracturing a subterranean formulation, the method comprising: (i) selecting recovered water; (ii) contacting said recovered water with a viscosifying agent; (iii) contacting said recovered water with one or more other additives; and (iv) adjusting the pH to pH 6.5-8.8. ### Claim 2 (depends on 1) The method according to claim 1, wherein said recovered water has a total dissolved solids (TDS) of at least 150,000 ppm. ### Claim 3 (depends on 1) The method according to claim 1, wherein said recovered water includes: greater than 1000 ppm magnesium ions; and/or greater than 10,000 ppm of calcium ions; and/or greater than 500 ppm of strontium ions; and/or greater than 200 ppm of boron ions. ### Claim 4 (depends on 1) The method according to claim 1, wherein said viscosifying agent comprises a polysaccharide. ### Claim 5 (depends on 1) The method according to claim 1, wherein said viscosifying agent is selected from fenugreek gum, tara gum, locust bean gum, guar gum, and derivatives thereof. ### Claim 6 (depends on 1) The method according to claim 1, wherein said viscosifying agent is non-ionic. ### Claim 7 (depends on 1) The method according to claim 1, wherein said viscosifying agent is guar or a guar derivative. ### Claim 8 (depends on 1) The method according to claim 1, wherein said viscosifying agent is guar which is non-derivatized. ### Claim 9 (depends on 1) The method according to claim 1, which comprises contacting said recovered water with at least 0.15 wt % of said viscosifying agent; and less than 0.40 wt % of said viscosifying agent. ### Claim 10 (depends on 1) The method according to claim 1, which comprises assessing the pH of the recovered water prior to step (ii) and, if the pH is greater than pH 6.5, taking steps to reduce the pH. ### Claim 11 (depends on 1) The method according to claim 1, wherein immediately before step (ii), the pH of the recovered water with which the viscosifying agent is contacted in step (ii) is less than 6.5. ### Claim 12 (depends on 1) The method according to claim 1, which includes the step of contacting said recovered water with a cross-linking agent (A) fir cross-linking said viscosifying agent. ### Claim 13 (depends on 12) The method according to claim 12, wherein contact of said recovered water with cross-linking agent (A) takes place when the pH of said recovered water is less than pH 6.5. ### Claim 14 (depends on 12) The method according to claim 12, wherein said cross-linking agent (A) is a transition metal. ### Claim 15 (depends on 12) The method according to claim 12, wherein said cross-linking agent (A) is a zirconium-based complex. ### Claim 16 (depends on 12) The method according to claim 12, wherein said cross-linking agents (A) is stabilized by an alcohol amine. ### Claim 17 (depends on 1) The method according to claim 1, wherein after said viscosifying agent has been contacted with said recovered water in step (ii), one or more additives is contacted with the recovered water in step (iii). ### Claim 18 (depends on 1) The method according to claim 1, wherein in step (iii), said method comprises contacting the recovered water with one or more scale inhibitors. ### Claim 19 (depends on 18) The method according to claim 18, wherein said one or more scale inhibitors are selected from phosphonate-based and acrylate-based scale inhibitors. ### Claim 20 (depends on 1) The method according to claim 1, wherein, in step (iii) or subsequent thereto, the method includes a step of contacting the recovered water with a cross-linking agent (B) which may be boron-based. ### Claim 21 (depends on 1) The method according to claim 1, wherein step (iv) includes increasing the pH of the fracturing fluid to pH 6.5-8.8. ### Claim 22 (depends on 1) A fracturing fluid made in the method of claim 1. ### Claim 23 A fracturing fluid which includes recovered water which has been recovered from a subterranean formation, a viscosifying agent which is cross-linked by a cross-linking agent (A), wherein said fracturing fluid has a pH of at least 6.1 and 8.8 or less. ### Claim 24 (canceled) ### Claim 25 (depends on 23) The fracturing fluid according to claim 23, wherein said viscosifying agent comprises a cross-linked polysaccharide. ### Claim 26 (depends on 23) The fracturing fluid according to claim 23, wherein said viscosifying agent is a non-derivatized guar. ### Claim 27 (depends on 23) The fracturing fluid according to claim 23, wherein said viscosifying agent, for example said guar, is cross-linked by a zirconium complex. ### Claim 28 (depends on 23) The fracturing fluid according to claim 23, wherein said fracturing fluid includes one or more scale inhibitors. ### Claim 29 (depends on 28) The fracturing fluid according to claim 28, wherein said one or more scale inhibitors are selected from phosphonate-based and acrylate-based scale inhibitors. ### Claim 30 (depends on 23) The fracturing fluid according to claim 23, wherein said fracturing fluid includes a cross-linking agent (B) which is boron-based. ### Claim 31 (canceled)