Set-delayed cement compositions comprising pumice and associated methods

1. A method of cementing in a subterranean formation, comprising:

providing a set-delayed cement composition comprising water, pumice, hydrated lime, a dispersant, and a set retarder; wherein the set retarder comprises a phosphonic acid derivative and the dispersant comprises a polycarboxylated ether dispersant;

activating the set-delayed cement composition;

introducing the set-delayed cement composition into a subterranean formation; and

allowing the set-delayed cement composition to set in the subterranean formation.

2. The method of claim 1 wherein the pumice has a mean particle size in a range of about 1 micron to about 200 microns.

3. The method of claim 1 wherein the pumice and the hydrated lime are present in a weight ratio of pumice to hydrated lime of about 10:1 to about 1:1.

4. The method of claim 1 wherein the set-delayed cement composition comprises a pumice-to-hydrated-lime weight ratio of about 3:1 to about 5:1, wherein the set retarder is present in an amount of about 0.01% to about 2% by weight of the pumice, and wherein the polycarboxylated ether dispersant is present in an amount of about 0.01% to about 2% by weight of the pumice.

5. The method of claim 1 wherein the set-delayed cement composition further comprises at least one additive selected from the group consisting of a weighting agent, a lightweight additive, a gas-generating additive, a mechanical-property-enhancing additive, a lost-circulation material, a filtration-control additive, a fluid-loss-control additive, a defoaming agent, a foaming agent, a thixotropic additive, and any combination thereof.

6. The method of claim 1 wherein the set-delayed cement composition remains in a pumpable fluid state for a time period of at least about 7 days prior to the activating.

7. The method of claim 1 wherein the set-delayed cement composition remains in a pumpable fluid state for a time period of at least about 30 days prior to the activating.

8. The method of claim 1 wherein the activating comprises adding a cement set accelerator to the set-delayed cement composition.

9. The method of claim 1 wherein the set-delayed cement composition sets to develop a 24-hour compressive strength of at least about 50 psi as measured using an Ultrasonic Cement Analyzer at 140° F. while maintained at 3,000 psi.

10. The method of claim 1 wherein the set-delayed cement composition is introduced into a well bore penetrating the subterranean formation, the well bore having a bottom-hole static temperature of less than about 200° F.

11. The method of claim 1 wherein the set-delayed cement composition is introduced into an annulus between a wall of a well bore and a conduit disposed in the well bore.

12. A method of cementing in a subterranean formation, comprising:

providing a set-delayed cement composition comprising water, pumice, hydrated lime, a dispersant, and a set retarder; wherein the set retarder comprises a phosphonic acid derivative and the dispersant comprises a polycarboxylated ether dispersant;

storing the set-delayed cement composition for a period of at least about 1 day;

adding a cement set accelerator to the set-delayed cement composition;

introducing the set-delayed cement composition into a subterranean formation; and

allowing the set-delayed cement composition to set in the subterranean formation.

13. The method of claim 12 wherein the pumice and the hydrated lime are present in a weight ratio of pumice to hydrated lime of about 10:1 to about 1:1.

14. The method of claim 12 wherein the set-delayed cement composition is stored for a time period of at least about 30 days.

15. The method of claim 12 wherein the pumice has a mean particle size in a range of about 1 micron to about 200 microns.

16. The method of claim 12 wherein the set-delayed cement composition comprises a pumice-to-hydrated-lime weight ratio of about 3:1 to about 5:1, wherein the set retarder is present in an amount of about 0.01% to about 2% by weight of the pumice, and wherein the polycarboxylated ether dispersant is present in an amount of about 0.01% to about 2% by weight of the pumice.

17. The method of claim 12 wherein the set-delayed cement composition remains is stored for a time period of at least about 7 days.

18. The method of claim 12 wherein the set-delayed cement composition is introduced into a well bore penetrating the subterranean formation, the well bore having a bottom-hole static temperature of about 200° F. or less.

19. The method of claim 12 wherein the set-delayed cement composition is introduced into an annulus between a wall of a well bore and a conduit disposed in the well bore.

20. A method of cementing in a subterranean formation, comprising:

providing a cement composition comprising water, pumice, hydrated lime, a dispersant, and a set retarder, wherein the set retarder comprises a phosphonic acid derivative and the dispersant comprises a polycarboxylated ether dispersant, wherein the water is present in an amount of about 33% to about 200% by weight of the pumice, wherein the hydrated lime is present in an amount of about 10% to about 100% by weight of the pumice;

storing the cement composition in a pumpable fluid state for a period of about 1 day or longer;

activating the cement composition;

introducing the cement composition into a space between a wellbore wall and a subterranean formation; and

allowing the cement composition to set in the space.

21. The method of claim 20 wherein the cement composition is stored for a period of about 7 days or longer.