# US 7,407,009 B2 · Methods of using cement compositions comprising phosphate compounds in subterranean formations

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- Number: US 7,407,009 B2
- Document ID: US7407009B2
- Status: Granted
- Kind: B2
- Application number: 11/014,547
- Filed: 2004-12-16
- Published: 2006-06-22
- Granted: 2008-08-05
- Earliest claimed: 2004-12-16
- Assignees: Halliburton Energy Services, Inc.
- Inventors: Ashok K. Santra; Ronald J. Crook; Bobby J. King
- Web page: https://patentgrep.com/patent/US7407009B2

## CPC

- C04B 28/342: {the phosphate binder being present in the starting composition as a mixture of free acid and one or more reactive oxides}
- C09K 8/424: {using "spacer" compositions}
- C09K 8/487: Fluid loss control additives; Additives for reducing or preventing circulation loss
- C09K 8/5045: {containing inorganic compounds}
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE
- C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE

## Abstract

Methods of using cement compositions comprising phosphate compounds in subterranean formations are provided. An example of a method is a method of cementing in a subterranean formation. Other examples of methods include methods of avoiding the loss of circulation in a subterranean formation. Other examples of methods include methods of drilling in a subterranean formation.

## Claims

### Claim 1

A method of cementing in a subterranean formation, comprising:
providing a first slurry that comprises a metal oxide or hydroxide;
providing a second slurry that comprises a phosphate compound and a water source;
sequentially placing the first and second slurries into a portion of a well bore that penetrates a subterranean formation;
permitting the first and second slurries to contact each other within the subterranean formation such that the metal oxide or hydroxide, the water source, and the phosphate compound react to form a cement composition; and
allowing the cement composition to set in the formation and at least partially bond the walls of the well bore to the exterior surface of a pipe string disposed in the well bore.

### Claim 2 (depends on 1)

The method of claim 1, wherein the first slurry further comprises an oil-based fluid.

### Claim 3 (depends on 1)

The method of claim 1, wherein the first slurry further comprises a synthetic-based fluid.

### Claim 4 (depends on 1)

The method of claim 1, wherein sequentially placing the first and second slurries into a portion of a subterranean formation comprises separating the first slurry from the second slurry with a spacer fluid.

### Claim 5 (depends on 1)

The method of claim 1, wherein the phosphate compound has the formula
A3-x(HxPO4),
where A comprises hydrogen, an alkali metal, or an ammonium ion, and where X is from about 1 to about 3.

### Claim 6 (depends on 1)

The method of claim 1, wherein the metal oxide or hydroxide comprises magnesium oxide.

### Claim 7 (depends on 1)

The method of claim 1, wherein sequentially placing the first and second slurries into a portion of a subterranean formation comprises placing the first slurry into the portion of the subterranean formation and thereafter placing the second slurry into the portion of the subterranean formation.

### Claim 8 (depends on 1)

The method of claim 1, wherein sequentially placing the first and second slurries into a portion of a subterranean formation comprises placing the second slurry into the portion of the subterranean formation and thereafter placing the first slurry into the portion of the subterranean formation.

### Claim 9

A method of avoiding the loss of circulation in a subterranean formation, comprising:
providing a first slurry that comprises a metal oxide or hydroxide;
providing a second slurry that comprises a phosphate compound and a water source;
temporarily suspending the drilling of a borehole in a subterranean formation;
during the temporary suspension of drilling, sequentially placing the first and second slurries into a portion of the borehole in the subterranean formation adjacent openings in the subterranean formation in fluid communication with the borehole;
contacting the first slurry with the second slurry adjacent the openings;
permitting the first slurry and the second slurry to set to form a plug that seals the openings off from the borehole; and
resuming drilling.

### Claim 10 (depends on 9)

The method of claim 9, wherein the first slurry further comprises an oil-based fluid.

### Claim 11 (depends on 9)

The method of claim 9, wherein the first slurry further comprises a synthetic-based fluid.

### Claim 12 (depends on 9)

The method of claim 9, wherein sequentially placing the first and second slurries into a portion of a borehole in a subterranean formation comprises separating the first slurry from the second slurry with a spacer fluid.

### Claim 13 (depends on 9)

The method of claim 9, wherein the phosphate compound has the formula
A3-x(HxPO4)
where A comprises hydrogen, an alkali metal, or an ammonium ion, and where X is from about 1 to about 3.

### Claim 14 (depends on 9)

The method of claim 9, wherein the metal oxide or hydroxide comprises magnesium oxide.

### Claim 15 (depends on 9)

The method of claim 9, wherein sequentially placing the first and second slurries into a portion of a borehole in a subterranean formation comprises placing the first slurry into the portion of the borehole and thereafter placing the second slurry into the portion of the borehole.

### Claim 16 (depends on 9)

The method of claim 9, wherein sequentially placing the first and second slurries into a portion of a borehole in a subterranean formation comprises placing the second slurry into the portion of the borehole and thereafter placing the first slurry into the portion of the borehole.

### Claim 17

A method of avoiding the loss of circulation in a subterranean formation, comprising:
providing a cement composition that comprises a metal oxide or hydroxide, a phosphate compound, a set retarder that comprises a sugar and a borate compound, and a water source;
temporarily suspending the drilling of a borehole in a subterranean formation;
during the temporary suspension of drilling, placing the cement composition into a portion of the borehole in the subterranean formation adjacent openings in a region of the subterranean formation in fluid communication with the borehole;
permitting the cement composition to set within the subterranean formation adjacent the openings so as to form a plug that seals the openings off from the borehole; and
resuming drilling.

### Claim 18 (depends on 17)

The method of claim 17 wherein the phosphate compound has the formula
A3-x(HxPO4)
where A comprises hydrogen, an alkali metal, or an ammonium, and where X is from about 1 to about 3.

### Claim 19 (depends on 17)

The method of claim 17 wherein the metal oxide or hydroxide comprises magnesium oxide.

### Claim 20 (depends on 17)

The method of claim 17 wherein the metal oxide or hydroxide comprises magnesium oxide that has been calcined at a temperature greater than or equal to about 3,632° F.

### Claim 21

A method of cementing in a subterranean formation, comprising:
providing a first slurry that comprises a metal oxide or hydroxide;
providing a second slurry that comprises a phosphate compound and a water source;
placing the first and second slurries separately into a portion of a well bore that penetrates a subterranean formation by separating the first slurry from the second slurry with a spacer fluid;
permitting the first and second slurries to contact each other within the subterranean formation such that the metal oxide or hydroxide, the water source, and the phosphate compound react to form a cement composition; and
allowing the cement composition to set in the formation and at least partially bond the walls of the well bore to the exterior surface of a pipe string disposed in the well bore.

### Claim 22 (depends on 21)

The method of claim 21, wherein the first slurry further comprises an oil-based fluid.

### Claim 23 (depends on 21)

The method of claim 21, wherein the first slurry further comprises a synthetic-based fluid.

### Claim 24 (depends on 21)

The method of claim 21, wherein the phosphate compound has the formula
A3-x(HxPO4),
where A comprises hydrogen, an alkali metal, or an ammonium ion, and where X is from about 1 to about 3.

### Claim 25 (depends on 21)

The method of claim 21, wherein the metal oxide or hydroxide comprises magnesium oxide.

### Claim 26

A method of servicing a subterranean formation, comprising:
providing a first slurry that comprises a metal oxide or hydroxide dispersed in a fluid that comprises at least one fluid selected from the group consisting of an oil-based or a synthetic-based fluid;
providing a second slurry that comprises a phosphate compound and a water source;
placing the first and second slurries separately into a subterranean formation, wherein either the first or second slurry is introduced through a pipe string disposed in a well bore and the other slurry is introduced through an annulus defined by the outer surface of the pipe string and the walls of the well bore;
permitting the first and second slurries to contact each other within the subterranean formation such that the metal oxide or hydroxide, the water source, and the phosphate compound react to form a cement composition; and
allowing the cement composition to set in the formation.

### Claim 27 (depends on 26)

The method of claim 26, wherein the phosphate compound has the formula
A3-x(HxPO4),
where A comprises hydrogen, an alkali metal, or an ammonium ion, and where X is from about 1 to about 3.