Compositions for enhancing viscosity of subterranean fluids utilizing chelating agents
A composition for use in well stimulation operations, the composition comprising a saline fluid, the saline fluid comprising between 50,000 ppm and 70,000 ppm; a polymer, the polymer operable to react with a crosslinker to increase a viscosity of the saline fluid; a zirconium crosslinker, the zirconium crosslinker operable to react with the polymer; and a chelating agent, the chelating agent comprises L-glutamic acid N, N diacetic acid (GLDA), wherein the GLDA is present in an amount between 1 wt % and 8 w t %.
1 . A composition for use in well stimulation operations, the composition comprising:
a saline fluid, the saline fluid comprising between 50,000 ppm and 70,000 ppm;
a polymer, the polymer operable to react with a crosslinker to increase a viscosity of the saline fluid, wherein the polymer is present in an amount between 0.5 wt % and 0.6 wt %;
a zirconium crosslinker, the zirconium crosslinker operable to react with the polymer, wherein the zirconium crosslinker is present in an amount of 1 wt %; and
a chelating agent, the chelating agent comprises L-glutamic acid N, N diacetic acid (GLDA), wherein the GLDA is present in an amount between 1 wt % and 8 wt %,
wherein the composition has a viscosity in the range between 90 cP and 1000 cP after 4 hours,
wherein the composition has a pH between 10 and 14 where pH greater than 10 activates the zirconium crosslinker.
2 . The composition of claim 1 , wherein the saline fluid can be selected from the group consisting of seawater, produced water, and combinations of the same.
3 . The composition of claim 1 , wherein the polymer comprises carboxymethyl hydroxypropyl guar (CMHPG) polymer.
4 . The composition of claim 1 , wherein the composition has a viscosity in the range between 90 cP and 1000 cP.
5 . A method of using a hydraulic fracturing fluid, the method comprising the step of:
injecting the hydraulic fracturing fluid into a formation during a well stimulation operation, wherein the hydraulic fracturing fluid comprises:
a saline fluid, the saline fluid comprising between 50,000 ppm and 70,000 ppm;
a polymer, the polymer operable to react with a crosslinker to increase a viscosity of the saline fluid, wherein the polymer is present in an amount between 0.5 wt % and 0.6 wt %;
a zirconium crosslinker, the zirconium crosslinker operable to react with the polymer wherein the zirconium crosslinker is present in an amount of 1 wt %; and
a chelating agent, the chelating agent comprises L-glutamic acid N, N diacetic acid (GLDA), wherein the GLDA is present in an amount between 1 wt % and 8 wt %; and
wherein the hydraulic fracturing fluid has a viscosity of 1000 cP before reaching the formation and a viscosity of between 90 cP and 100 cP after 1 hour, wherein the hydraulic fracturing fluid has a pH between 10 and 14, where pH greater than 10 activates the zirconium crosslinker.
6 . The method of claim 5 , wherein the well stimulation operation is selected from the group consisting of fracturing and proppant transport.
7 . The method of claim 5 , wherein the saline fluid can be selected from the group consisting of seawater, produced water, and combinations of the same.
8 . The method of claim 5 , wherein the polymer comprises carboxymethyl hydroxypropyl guar (CMHPG) polymer.