Drilling method using high density, high strength, acid soluble pseudo-crosslinked, lost circulation preventative material

Patent metadata

Field	Value
Publication number	US-2017190622-A1
Application number	US-201715459975-A
Country	US
Kind code	A1
Filing date	Mar 15, 2017
Priority date	Jun 3, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

A formulation for use as a lost circulation preventive material is a cement-forming aqueous fluid comprising water, a viscoelastic surfactant (VES), a monovalent or multivalent salt, a magnesium powder, a retarder, a weighting material, and a dispersant. The formulation is used in a method of drilling into a subterranean formation that includes introducing into a wellbore passing at least partially through the subterranean formation the cement-forming aqueous fluid, and further increasing the viscosity of the aqueous fluid with the VES; where the monovalent salt is present in an amount effective to pseudo-crosslink the elongated VES micelles to further increase the viscosity of fluid. The formulation further forms a cement by reacting the magnesium powder and the water which reaction is retarded by the retarder. The water may be saline water. When the fluid density is greater than 14 pounds per gallon, a dispersant is required, such as a sulfonated copolymer.

First claim

What is claimed is:

1 . A method of drilling into a subterranean formation comprising:
introducing into a wellbore passing at least partially through the subterranean formation a cement-forming aqueous fluid having a density greater than 14 pounds per gallon (ppg) (1.7 kg/L) comprising:
water;
at least one viscoelastic surfactant (VES);
at least one monovalent or multivalent salt;
at least one magnesium powder comprising:
30-80 wt % MgO, and
greater than 20 wt % dolomite,

which magnesium powder works as cement;
at least one retarder;
at least one weighting material; and
at least one dispersing agent; increasing the viscosity of the cement-forming aqueous fluid by the action of the at least one VES forming elongated micelles; where the at least one monovalent salt or multivalent salt is present in an amount effective to pseudo-crosslink the elongated VES micelles to further increase the viscosity of the aqueous fluid; forming a cement by reacting the at least one magnesium powder and the water, where the forming of cement is retarded from that which would otherwise occur but for the presence of the retarder; and inhibiting fluid loss of the fluid into the formation by the combined action of the pseudo-crosslinked VES micelles and the cement.

2 . The method of claim 1 where the weighting material is selected from barium sulfate, micronized barite, hausmannite, ilmenite, manganese tetroxide, hematite, calcium carbonate, magnetite, and combinations of these.

3 . The method of claim 2 wherein the weighting material is present in an amount of about 1% to 150% bwoc.

4 . The method of claim 1 where the dispersing agent comprises a sulfonated copolymer.

5 . The method of claim 4 wherein the sulfonated copolymer is present in an amount of about 0.01% to 2% bwoc.

6 . The method of claim 1 where the at least one VES is present in the cement-forming aqueous fluid in a range of from about 0.01 wt % to about 10 wt % based on the water.

7 . The method of claim 1 where the at least one VES is present in the cement-forming aqueous fluid in an amount from about 0.01 gps to 2 gps.

8 . The method of claim 1 where the at least one monovalent or multivalent salt is selected from the group consisting of sodium chloride, potassium chloride, ammonium chloride, sodium bromide, sodium formate, potassium formate, calcium chloride, calcium bromide, magnesium chloride, zinc chloride, zinc bromide, aluminum chloride, and combinations thereof.

9 . The method of claim 8 where an amount of the at least one monovalent or multivalent salt is present in the water in an amount from about 0.05 bwoc to above saturation.

10 . The method of claim 1 where the at least one retarder is selected from the group consisting of sodium borate, boric acid, disodium tetraborate decahydrate, and combinations thereof.

11 . The method of claim 1 where the at least one retarder is present in the aqueous fluid in an amount from about 0.01 to about 20% bwoc.

12 . The method of claim 1 where the cement has an acid solubility greater than 90%

13 . The method of claim 1 where the cement has a compressive strength greater than 300 psi.

14 . A method of drilling into a subterranean formation comprising:
introducing into a wellbore passing at least partially through the subterranean formation a cement-forming aqueous fluid having a density greater than 14 pounds per gallon (ppg) (1.7 kg/L) comprising:
water;
at least one viscoelastic surfactant (VES);
at least one monovalent or multivalent salt selected from the group consisting of sodium chloride, potassium chloride, ammonium chloride, sodium bromide, sodium formate, potassium formate, calcium chloride, calcium bromide, magnesium chloride, zinc chloride, zinc bromide, aluminum chloride, and combinations thereof;
at least one magnesium powder comprising:
30-80 wt % MgO, and
greater than 20 wt % dolomite,

which magnesium powder works as cement;
at least one retarder;
at least one weighting material selected from barium sulfate, micronized barite, hausmannite, ilmenite, manganese tetroxide, hematite, calcium carbonate, magnetite, and combinations of these; and
at least one dispersing agent;
increasing the viscosity of the cement-forming aqueous fluid by the action of the at least one VES forming elongated micelles; where the at least one monovalent salt or multivalent salt is present in an amount effective to pseudo-crosslink the elongated VES micelles to further increase the viscosity of the aqueous fluid; forming a cement by reacting the at least one magnesium powder and the water, where the forming of cement is retarded from that which would otherwise occur but for the presence of the retarder; and inhibiting fluid loss of the fluid into the formation by the combined action of the pseudo-crosslinked VES micelles and the cement.

15 . The method of claim 14 wherein the weighting material is present in an amount of about 1% to 150% bwoc.

16 . The method of claim 14 where the at least one VES is present in the cement-forming aqueous fluid in a range of from about 0.01 wt % to about 10 wt % based on the water.

17 . The method of claim 14 where the at least one VES is present in the cement-forming aqueous fluid in an amount from about 0.01 gps to 2 gps.

18 . The method of claim 17 where an amount of the at least one monovalent or multivalent salt is present in the water in an amount from about 0.05 bwoc to above saturation.

19 . The method of claim 14 where the at least one retarder is present in the aqueous fluid in an amount from about 0.01 to about 20% bwoc.

20 . A method of drilling into a subterranean formation comprising:
introducing into a wellbore passing at least partially through the subterranean formation a cement-forming aqueous fluid having a density greater than 14 pounds per gallon (ppg) (1.7 kg/L) comprising:
water;
at least one viscoelastic surfactant (VES),
at least one monovalent or multivalent salt selected from the group consisting of sodium chloride, potassium chloride, ammonium chloride, sodium bromide, sodium formate, potassium formate, calcium chloride, calcium bromide, magnesium chloride, zinc chloride, zinc bromide, aluminum chloride, and combinations thereof, where an amount of the at least one monovalent or multivalent salt is from about 0.05 bwoc to above saturation;
at least one magnesium powder comprising:
30-80 wt % MgO, and
greater than 20 wt % dolomite,

which magnesium powder works as cement;
at least one retarder present in an amount from about 0.01 to about 20% bwoc;
at least one weighting material present in an amount of about 1% to 150% bwoc, where the at least one weighting material is selected from barium sulfate, micronized barite, hausmannite, ilmenite, manganese tetroxide, hematite, calcium carbonate, magnetite, and combinations of these; and
at least one dispersing agent present in an amount of about 0.01% to 2% bwoc;
increasing the viscosity of the cement-forming aqueous fluid by the action of the at least one VES forming elongated micelles; where the at least one monovalent salt or multivalent salt is present in an amount effective to pseudo-crosslink the elongated VES micelles to further increase the viscosity of the aqueous fluid; forming a cement by reacting the at least one magnesium powder and the water, where the forming of cement is retarded from that which would otherwise occur but for the presence of the retarder; and inhibiting fluid loss of the fluid into the for

Assignees

• Baker Hughes Inc

Inventors

• Yadav Prahlad Kumar
• Sarmah Pranjal
• Agrawal Gaurav
• Huang Tianping

Classifications

• C04B2201/20

  for the density · CPC title

• C09K8/48

  Density increasing or weighting additives · CPC title

• C09K8/487 Primary

  Fluid loss control additives; Additives for reducing or preventing circulation loss · CPC title

• E21B33/138

  Plastering the borehole wall; Injecting into the formation · CPC title

• C09K8/42 Primary

  Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells (compositions for plastering C09K8/50) · CPC title