# US 2021/0079291 A1 · 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 2021/0079291 A1 - Document ID: US20210079291A1 - Status: Published application - Kind: A1 - Application number: 16/842,438 - Filed: 2020-04-07 - Published: 2021-03-18 - Earliest claimed: 2019-09-18 - Assignees: Multi-Chem Group, LLC - Applicants: Multi-Chem Group LLC - Inventors: Leiming Li; Scot Harris Bodnar; Liang Xu; James William Ogle; Todd Allen Collier - Web page: https://patentgrep.com/patent/US20210079291A1 ## 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 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. ### Claim 2 (depends on 1) The method of claim 1 wherein the step of preparing or providing comprises dissolving an iron containing compound in water or reacting an iron containing compound to release iron ions in water. ### Claim 3 (depends on 2) The method of claim 2 wherein the iron containing compound is FeCl2. ### Claim 4 (depends on 1) The method of claim 1 wherein the aqueous fluid further comprises 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 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 related salts, their corresponding esters, or combinations thereof. ### Claim 6 (depends on 1) The method of claim 1 wherein the fracturing fluid comprises water, the at least one friction reducer, and a proppant. ### Claim 7 (depends on 6) The method of claim 6 wherein the water comprises at least one of surface water, ground water, sea water, or produced water. ### Claim 8 (depends on 1) The method of claim 1 further comprising introducing the fracturing fluid into a subterranean formation. ### Claim 9 A method of preparing a fracturing fluid comprising: preparing a laboratory treatment fluid based at least in part on a diluted treatment fluid model; screening a plurality of friction reducers against the laboratory treatment fluid; 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. ### Claim 10 (depends on 9) The method of claim 9 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 11 (depends on 10) The method of claim 10 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 such that a concentration of iron in the laboratory treatment fluid in the range of about 50% to about 500% of the diluted treatment fluid model. ### Claim 12 (depends on 10) The method of claim 10 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 13 (depends on 12) The method of claim 12 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 14 (depends on 9) The method of claim 9 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 15 (depends on 9) The method of claim 9 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 related salts, their corresponding esters, or combinations thereof. ### Claim 16 (depends on 9) The method of claim 9 wherein the fracturing fluid comprises water, the at least one friction reducer, and a proppant. ### Claim 17 (depends on 9) The method of claim 9 further comprising introducing the fracturing fluid into a subterranean formation. ### Claim 18 A method comprising: preparing a fluid comprising water and iron ions in an amount greater than 1000 ppm; screening a plurality of friction reducers against the fluid; 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. ### Claim 19 (depends on 18) The method of claim 18 wherein iron ions are present in an amount at a point in a range of about 1500 ppm to about 2500 ppm. ### Claim 20 (depends on 18) The method of claim 18 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 related salts, their corresponding esters, or combinations thereof.