# US 11,441,067 B2 · Screening method for friction reducer precipitation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,441,067 B2 - Document ID: US11441067B2 - Status: Granted - Kind: B2 - Application number: 16/842,438 - Filed: 2020-04-07 - Published: 2021-03-18 - Granted: 2022-09-13 - Earliest claimed: 2019-09-18 - Assignees: Halliburton Energy Services, Inc. - Applicants: Halliburton Energy Services, Inc. - Inventors: Leiming Li; Scot Harris Bodnar; Liang Xu; James William Ogle; Todd Allen Collier - Web page: https://patentgrep.com/patent/US11441067B2 ## CPC - C09K 8/68: containing organic compounds - C09K 8/80: Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open - C09K 8/88: macromolecular compounds - C09K 8/882: {obtained by reactions only involving carbon-to-carbon unsaturated bonds} - C09K 2208/28: Friction or drag reducing additives - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract A method of preparing a fracturing fluid comprising: preparing or providing an aqueous fluid containing iron ions; screening a plurality of friction reducers against the aqueous fluid wherein the plurality of friction reducers are anionic, cationic, nonionic, amphoteric, or combinations thereof; selecting at least one friction reducer from the plurality of friction reducers based at least in part on the step of screening; and preparing a fracturing fluid including the at least one friction reducer. ## Claims ### Claim 1 A method of preparing a fracturing fluid comprising: preparing a laboratory treatment fluid based at least in part on a treatment fluid model; screening a plurality of friction reducers against the laboratory treatment fluid, the screening comprising: dissolving at least 2,000 ppm of Fe2+ ions into water and adding about 2 gpt to about 5 gpt of a friction reducer; storing the water for at least about a day and monitoring formation of precipitates of hydrated friction reducing polymers; filtering the precipitates, drying the precipitates, and weighing the precipitates; selecting at least one friction reducer from the plurality of friction reducers based at least in part on the step of screening and the presence of precipitate; and preparing a fracturing fluid including the at least one friction reducer. ### Claim 2 (depends on 1) The method of claim 1 wherein the diluted treatment fluid model includes a concentration of dissolved species in a diluted formation fluid, wherein the dissolved species comprises at least iron. ### Claim 3 (depends on 2) The method of claim 2 wherein the step of preparing a laboratory treatment fluid comprises dissolving an iron containing compound in water or reacting an iron containing compound to release iron ions in water. ### Claim 4 (depends on 2) The method of claim 2 wherein the diluted treatment fluid model further includes a concentration of at least one ion selected from the group consisting of calcium ions, magnesium ions, sodium ions, barium ions, chloride ions, and combinations thereof. ### Claim 5 (depends on 4) The method of claim 4 wherein the step of preparing a laboratory treatment fluid comprises dissolving a compound containing at least one of iron ions, calcium ions, magnesium ions, sodium ions, barium ions, chloride ions, and combinations thereof, in water such that a concentration of ions in the laboratory treatment fluid in the range of 50% to about 500% of the diluted treatment fluid model. ### Claim 6 (depends on 1) The method of claim 1 wherein the diluted treatment fluid model is based at least in part on measurement of a volume of formation brine and concentration of dissolved species therein and a volume of treatment fluid and concentration of dissolved species therein. ### Claim 7 (depends on 1) The method of claim 1 wherein the plurality of friction reducers comprise at least one of a polyacrylamide, a polyacrylamide derivative, a synthetic polymer, an acrylamide copolymer, an anionic acrylamide copolymer, a cationic acrylamide copolymer, a nonionic acrylamide copolymer, an amphoteric acrylamide copolymer, a polyacrylate, a polyacrylate derivative, a polymethacrylate, a polymethacrylate derivative, polymers synthesized from one or more monomeric units selected from the group consisting of acrylamide, acrylic acid, 2-acrylamido-2-methylpropane sulfonic acid, acrylamido tertiary butyl sulfonic acid, N,N-dimethylacrylamide, vinyl sulfonic acid, N-vinyl acetamide, N-vinyl formamide, itaconic acid, methacrylic acid, acrylic acid esters, or methacrylic acid esters, their corresponding salts, their corresponding esters, or combinations thereof. ### Claim 8 (depends on 1) The method of claim 1, wherein the fracturing fluid comprises water, the at least one friction reducer, and a proppant. ### Claim 9 (depends on 1) The method of claim 1, further comprising introducing the fracturing fluid into a subterranean formation. ### Claim 10 (depends on 1) The method of claim 1, wherein the friction reducers are in an acid form or a salt form. ### Claim 11 (depends on 3) The method of claim 3, wherein the concentration of iron in the laboratory treatment fluid is in the range of about 50% to about 500% of the diluted treatment fluid model. ### Claim 12 (depends on 1) The method of claim 1, wherein the diluted treatment fluid model is based at least in part on measurements made using open-hole, cased hole, and seismic logging techniques to determine a volume of formation brine and concentration of dissolved species therein and a volume of treatment fluid and concentration of dissolved species therein. ### Claim 13 (depends on 1) The method of claim 1, further comprising subjecting the fracturing fluid to a wellbore pressure and a wellbore temperature to simulate a wellbore condition. ### Claim 14 (depends on 8) The method of claim 8, wherein the water comprises at least one of fresh water, produced water, sea water, ground water, or surface water. ### Claim 15 (depends on 2) The method of claim 2, wherein the iron containing compound is FeCl2. ### Claim 16 (depends on 5) The method of claim 5, further comprising subjecting the fracturing fluid to a wellbore pressure and a wellbore temperature to simulate a wellbore condition. ### Claim 17 (depends on 8) The method of claim 8 wherein the proppant is present at a point ranging from about 0.1 pounds per gallon to about 14 pounds per gallon.