초록

Methods, cement compositions and oil suspensions of powders are provided. The oil suspensions of silica powder comprise silica powder, mineral oil, an oleophilic clay, an oleophilic surfactant and a hydrophilic surfactant.

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What is claimed is: 1. A method of cementing a subterranean zone comprising: (a) preparing or providing a cement composition comprising a hydraulic cement, sufficient water to form a slurry and an oil suspension of silica powder that comprises silica powder, mineral oil, an oleophilic clay, an oleo

What is claimed is: 1. A method of cementing a subterranean zone comprising: (a) preparing or providing a cement composition comprising a hydraulic cement, sufficient water to form a slurry and an oil suspension of silica powder that comprises silica powder, mineral oil, an oleophilic clay, an oleophilic surfactant and a hydrophilic surfactant; (b) placing said cement composition in said subterranean zone; and (c) allowing said cement composition to set therein. 2. The method of claim 1 wherein said hydraulic cement is selected from the group consisting of Portland cements, slag cements, pozzolana cements, gypsum cements, aluminous cements and alkaline cements. 3. The method of claim 1 wherein said hydraulic cement is Portland cement. 4. The method of claim 1 wherein said water is selected from the group consisting of fresh water and salt water. 5. The method of claim 1 wherein said water is present in said cement composition in an amount in the range of from about 35% to about 65% by weight of hydraulic cement therein. 6. The method of claim 1 wherein said oil suspension is present in said cement composition in an amount in the range of from about 10% to about 70% by weight of hydraulic cement therein. 7. The method of claim 1 wherein said silica powder in said oil suspension is selected from the group consisting of crystalline silica and amorphous silica. 8. The method of claim 1 wherein said silica powder in said oil suspension is crystalline silica powder having a particle size in the general range of from about 15 microns to about 350 microns. 9. The method of claim 8 wherein said crystalline silica powder is present in said oil suspension in an amount in the range of from about 45% to about 52% by weight of said oil suspension. 10. The method of claim 1 wherein silica powder in said oil suspension is amorphous silica powder having a particle size in the general range of from about 5 microns to about 25 microns. 11. The method of claim 10 wherein said amorphous silica powder is present in said oil suspension in an amount in the range of from about 43% to about 47% by weight of said oil suspension. 12. The method of claim 1 wherein said mineral oil in said oil suspension has a viscosity at 100째 F. in the range of from about 60 saybolt seconds to about 100 saybolt seconds and is present in said oil suspension in an amount in the range of from about 40% to about 55% by weight of said oil suspension. 13. The method of claim 1 wherein said oleophilic clay is present in said oil suspension in an amount in the range of from about 0. 75 to about 5.5% by weight of said oil suspension. 14. The method of claim 1 wherein said oleophilic surfactant in said oil suspension is selected from the group consisting of sorbitantrioleate, sorbitantrilaurate, sorbitantripalmitate, sorbitantristearate and sorbitantrisesquioleate. 15. The method of claim 1 wherein said oleophilic surfactant in said oil suspension is sorbitantrioleate. 16. The method of claim 1 wherein said oleophilic surfactant is present in said oil suspension in an amount in the range of from about 0.1% to about 0.2% by weight of said oil suspension. 17. The method of claim 1 wherein said hydrophilic surfactant in said oil suspension is selected from the group consisting of polyethoxylated sorbitantrioleate, polyethoxylated sorbitantrilaurate, polyethoxylated sorbitantripalmitate, polyethoxylated sorbitantristearate and polyethoxylated sorbitantrisesquioleate. 18. The method of claim 1 wherein said hydrophilic surfactant in said oil suspension is polyethoxylated sorbitantrioleate. 19. The method of claim 1 wherein said hydrophilic surfactant is present in said oil suspension in an amount in the range of from about 2.5% to about 3.5% by weight of said oil suspension. 20. A method of cementing a subterranean zone comprising: (a) preparing or providing a cement composition comprising a hydraulic cement, sufficient water to form a slurry and an oil suspension comprising a powder selected from the group consisting of micro-silica, silica flour, fine silica flour, silica sand, fine particle size cement, ultra-fine particle size cement, fly ash, slag, vitrified shale and zeolite having a particle size in the range of from about 5 microns to about 350 microns; mineral oil; an oleophilic clay; an oleophilic surfactant; and a hydrophilic surfactant; (b) placing said cement composition in said subterranean zone; and (c) allowing said cement composition to set therein. 21. The method of claim 20 wherein said powder is present in said suspension in an amount in the range of from about 43% to about 52% by weight of said suspension. 22. The method of claim 20 wherein said hydraulic cement is selected from the group consisting of Portland cements, slag cements, pozzolana cements, gypsum cements, aluminous cements and alkaline cements. 23. The method of claim 20 wherein said hydraulic cement is Portland cement. 24. The method of claim 20 wherein said water is selected from the group consisting of fresh water and salt water. 25. The method of claim 20 wherein said water is present in said cement composition in an amount in the range of from about 35% to about 65% by weight of hydraulic cement therein. 26. The method of claim 20 wherein said oil suspension is present in said cement composition in an amount in the range of from about 10% to about 70% by weight of hydraulic cement therein. 27. A method of cementing a subterranean zone comprising: (a) preparing or providing a cement composition comprising a hydraulic cement, sufficient water to form a slurry and an oil suspension comprising a powder selected from the group consisting of micro-silica, silica flour, fine silica flour, silica sand, fine particle size cement, ultra-fine particle size cement, fly ash, slag, vitrified shale and zeolite; mineral oil; an oleophilic clay; an oleophilic surfactant; and a hydrophilic surfactant; (b) placing said cement composition in said subterranean zone; and (c) allowing said cement composition to set therein. 28. The method of claim 27 wherein said powder is present in said suspension in an amount in the range of from about 43% to about 52% by weight of said suspension. 29. The method of claim 27 wherein said hydraulic cement is selected from the group consisting of Portland cements, slag cements, pozzolana cements, gypsum cements, aluminous cements and alkaline cements. 30. The method of claim 27 wherein said hydraulic cement is Portland cement. 31. The method of claim 27 wherein said water is selected from the group consisting of fresh water and salt water. 32. The method of claim 27 wherein said water is present in said cement composition in an amount in the range of from about 35% to about 65% by weight of hydraulic cement therein. 33. The method of claim 27 wherein said oil suspension is present in said cement composition in an amount in the range of from about 10% to about 70% by weight of hydraulic cement therein.