Claims
- 1. A method of sealing pipe in a well bore penetrating a zone or formation which readily fractures at low hydrostatic pressures comprising the steps of:
(a) providing a lightweight cement composition comprised of a hydraulic cement, mix water and an additive comprising an aqueous suspension of microspheres containing a water swellable clay suspending agent; (b) placing said cement composition between the exterior surfaces of said pipe and the walls of said well bore; and (c) allowing said cement composition to set into a hard impermeable mass.
- 2. The method of claim 1 wherein said hydraulic cement in said composition is selected from the group of Portland cements, slag cements, pozzolana cements, gypsum cements, aluminous cements and silica cements.
- 3. The method of claim 1 wherein said hydraulic cement is Portland cement.
- 4. The method of claim 1 wherein said mix water is selected from the group consisting of fresh water, unsaturated salt solutions and saturated salt solutions.
- 5. The method of claim 1 wherein said water is present in said cement composition in an amount in the range of from about 60% to about 250% by weight of hydraulic cement therein.
- 6. The method of claim 1 wherein said additive is present in said composition in an amount in the range of from about 30% to about 100% by weight of hydraulic cement therein.
- 7. The method of claim 1 wherein said microspheres are fly ash microspheres.
- 8. The method of claim 1 wherein said microspheres are present in said additive in an amount in the range of from about 30% to about 100% by weight of water in said additive.
- 9. The method of claim 1 wherein said clay suspending agent is selected from the group consisting of sodium bentonite, attapulgite, kalonite, meta kalonite, hectorite and sepiolite.
- 10. The method of claim 1 wherein said clay suspending agent is sodium bentonite.
- 11 The method of claim 1 wherein said clay suspending agent is present in said additive in an amount in the range of from about 1% to about 4% by weight of water in said additive.
- 12. A lightweight well cement composition comprised of:
a hydraulic cement; mix water; and an additive comprised of an aqueous suspension of microspheres containing water, microspheres and a water swellable clay suspending agent.
- 13. The composition of claim 12 wherein said hydraulic cement is selected from the group of Portland cements, slag cements, pozzolana cements, gypsum cements, aluminous cements and silica cements.
- 14. The composition of claim 12 wherein said hydraulic cement is Portland cement.
- 15. The composition of claim 12 wherein said mix water is selected from the group consisting of fresh water, unsaturated salt solutions and saturated salt solutions.
- 16. The composition of claim 12 wherein said mix water is present in an amount in the range of from about 60% to about 250% by weight of hydraulic cement therein.
- 17. The composition of claim 12 wherein said additive is present in an amount in the range of from about 30% to about 100% by weight of hydraulic cement therein.
- 18. The composition of claim 12 wherein said microspheres are fly ash microspheres.
- 19. The composition of claim 12 wherein said microspheres are present in said additive in an amount in the range of from about 30% to about 100% by weight of water in said additive.
- 20. The composition of claim 12 wherein said clay suspending agent is selected from the group consisting of sodium bentonite, attapulgite, kalonite, meta kalonite, hectorite and sepiolite.
- 21. The composition of claim 12 wherein said clay suspending agent is sodium bentonite.
- 22. The composition of claim 12 wherein said clay suspending agent is present in said additive in an amount in the range of from about 1% to about 4% by weight of water in said additive.
- 23. A lightweight cement composition additive comprised of an aqueous suspension of microspheres containing water, microspheres and a water swellable clay suspending agent.
- 24. The additive of claim 23 wherein said microspheres are fly ash microspheres.
- 25. The additive of claim 23 wherein said microspheres are present in an amount in the range of from about 30% to about 100% by weight of water in said additive.
- 26. The additive of claim 23 wherein said clay suspending agent is selected from the group consisting of sodium bentonite, attapulgite, kalonite, meta kalonite, hectorite and sepiolite.
- 27. The additive of claim 23 wherein said clay suspending agent is sodium bentonite.
- 28. The additive of claim 23 wherein said clay suspending agent is present in an amount in the range of from about 1% to about 4% by weight of water in said additive.
- 29. The additive of claim 23 wherein said microspheres are present in an amount of about 67% by weight of water in said additive.
- 30. The additive of claim 27 wherein said sodium bentonite is present in an of about 2% by weight of water in said additive.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of application Ser. No. 10/005,266 filed on Dec. 3, 2001.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10005266 |
Dec 2001 |
US |
Child |
10103449 |
Mar 2002 |
US |