Mitigation of friction reducer precipitation

1. A method comprising:

preparing or providing an aqueous fluid containing iron ions;

screening at least one iron control agent against the aqueous fluid;

selecting at least one iron control agent and iron control agent concentration based at least in part on the step of screening;

screening a plurality of friction reducers against the aqueous fluid;

selecting at least one friction reducer from the plurality of friction reducers based at least in part on the step of screening;

preparing a fracturing fluid comprising an aqueous base fluid, the at least one friction reducer, and the at least one iron control agent wherein a concentration of the iron control agent in the fracturing fluid is greater than or equal to the selected iron control agent concentration.

2. 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.

3. The method of claim 2 wherein the iron containing compound is FeCl 2 .

4. 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, or combinations thereof.

5. The method of claim 1 wherein the iron control agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA), glutamic acid, N,N-diacetic acid (GLDA), salts thereof, or combinations thereof.

6. The method of claim 1 wherein the aqueous base fluid is at least one of surface water, ground water, or produced water.

7. 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.

8. The method of claim 1 wherein the fracturing fluid further comprises a proppant.

9. The method of claim 1 further comprising introducing the fracturing fluid into a subterranean formation.

10. 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 at least one iron control agent against the laboratory treatment fluid;

selecting at least one iron control agent and iron control agent concentration based at least in part on the step of screening;

screening a plurality of friction reducers against the aqueous 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 comprising an aqueous base fluid, the at least one friction reducer, and the at least one iron control agent wherein a concentration of the iron control agent in the fracturing fluid is greater than or equal to the selected iron control agent concentration.

11. 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.

12. The method of claim 10 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.

13. The method of claim 10 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.

14. The method of claim 10 wherein the iron control agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA), glutamic acid, N,N-diacetic acid (GLDA), salts thereof, or combinations thereof.

15. The method of claim 10 wherein the aqueous base fluid is at least one of surface water, ground water, or produced water.

16. The method of claim 10 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.

17. The method of claim 10 wherein the fracturing fluid further comprises a proppant.

18. The method of claim 10 further comprising introducing the fracturing fluid into a subterranean formation.