Claims
- 1. A method for grouting a water-flooded cavity, said method comprising the steps of:combining hydraulic cement and water in predetermined amounts so as to form a fluid cement slurry; colloidally mixing said cement slurry so as to achieve ultra-fine mixing thereof; mixing an anti-washout admixture with said cement slurry in a predetermined amount, said anti-washout admixture being substantially free of defoaming agents; mixing finished foam with said slurry after said slurry has been colloidally mixed and after said anti-washout admixture has been mixed with said slurry, so as to form a stable foamed cement grout; and injecting said foamed cement grout into said water-flooded cavity.
- 2. The method of claim 1, further comprising the step of:mixing a superplasticizing agent with said cement slurry in a predetermined amount.
- 3. The method of claim 2, wherein the step of mixing an anti-washout admixture with said cement slurry comprises:adding said anti-washout admixture to said cement slurry on a continuous basis at a predetermined metered rate.
- 4. The method of claim 3, wherein the step of mixing a superplasticizing agent with said cement slurry comprises:adding said superplasticizing agent to said cement slurry on a continuous basis at a predetermined metered rate.
- 5. The method of claim 1, wherein said anti-washout admixture comprises a modified cellulose ether solution.
- 6. The method of claim 1, wherein the step of mixing hyrdaulic cement and water comprises:mixing hydraulic cement and water in predetermined amounts so as to form a fluid cement slurry having a water-to-cement ratio in the range from about 0.4 to about 1.0.
- 7. The method of claim 6, wherein the step of mixing finished foam with said cement slurry comprises:mixing finished foam with said cement slurry in predetermined amounts so as to form a foamed cement grout having a unit weight in the range from about 40 pounds per cubic foot to about 90 pounds per cubic foot.
- 8. The method of claim 7, wherein the step of mixing finished foam with said cement slurry comprises:mixing finished foam with said cement slurry in predetermined amounts so as to form a foamed cement grout having a unit weight in the range from about 50 pounds per cubic foot to about 75 pounds per cubic foot.
- 9. The method of claim 7, wherein said anti-washout admixture comprises a modified cellulose ether solution.
- 10. The method of claim 9, wherein the step of mixing an anti-washout admixture with said cement slurry comprises:mixing said anti-washout admixture with said cement slurry in an amount in the range from about 5 ounces to about 20 ounces per hundredweight of cement.
- 11. The method of claim 10, wherein the step of mixing an anti-washout agent with said cement slurry comprises:mixing said anti-washout admixture with said cement slurry in an amount in the range from about 8 ounces to about 12 ounces per hundredweight of cement.
- 12. A composition for grouting grouting a water-flooded cavity, said composition comprising:hydraulic cement and water combined in predetermined amounts so as to form a fluid cement slurry; said cement slurry being colloidally mixed so as to achieve ultra-fine mixing thereof; an anti-washout admixture mixed with said cement slurry in a predetermined amount, said anti-washout admixture being substantially free of defoaming agents; and finished foam mixed with said slurry after said slurry has been colloidally mixed and after said anti-washout admixture has been mixed with said slurry, so as to form a stable foamed cement grout.
- 13. The composition of claim 12, further comprising:a superplasticizing agent mixed with said cement slurry in a predetermined amount.
- 14. The composition of claim 12, wherein said anti-washout admixture comprises a modified cellulose ether solution.
- 15. The composition of claim 12, wherein said fluid cement slurry has a water-to-cement ratio in the range from about 0.4 to about 1.0.
- 16. The composition of claim 15, wherein said foamed cement grout has a unit weight in the range from about 40 pounds per cubic foot to about 90 pounds per cubic foot.
- 17. The composition of claim 16, wherein said foamed cement grout has a unit weight in the range from about 50 pounds per cubic foot to about 75 pounds per cubic foot.
- 18. The composition of claim 16, wherein said anti-washout admixture comprises a modified cellulose ether solution.
- 19. The composition of claim 18, wherein said cement slurry comprises said anti-washout admixture mixed with said cement slurry in an amount in the range from about 5 ounces to about 20 ounces per hundredweight of cement.
- 20. A method for grouting a water-flooded cavity, said method comprising the steps of:combining Portland cement and water in predetermined amounts so as to form a fluid cement slurry having a water-to-cement ratio in the range from about 0.4 to about 1.0; colloidally mixing said cement slurry so as to achieve ultra-fine mixing thereof; mixing an anti-washout admixture with said cement slurry in a predetermined amount, said anti-washout admixture comprising a modified cellulose ether solution which is substantially free of defoaming agents; mixing a superplasticizing agent with said cement slurry in a predetermined amount, said superplasticizing agent being substantially free of defoaming agents; mixing finished foam with said slurry after said slurry has been colloidally mixed and after said anti-washout admixture has been mixed with said slurry, so as to form a stable foamed cement grout having a unit weight in the range from about 40 pounds per cubic foot to about 90 pounds per cubic foot; and injecting said foamed cement grout into said water-flooded cavity.
Parent Case Info
This application is a continuation of Ser. No. 09/199,394 filed Nov. 25, 1998, U.S. Pat. No. 6,167,912 which claims benefit of Provisional No. 60/066,853 filed Nov. 25, 1997.
US Referenced Citations (16)
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/066853 |
Nov 1997 |
US |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09/199394 |
Nov 1998 |
US |
Child |
09/753394 |
|
US |