초록 ▼

Cementing compositions and methods of cementing in a subterranean formation are provided. The cement composition includes a hydraulic cement, lightweight beads, and a desegregating agent for inhibiting segregation of the beads. The lightweight beads may be, for example, cenospheres, glass spheres, a

Cementing compositions and methods of cementing in a subterranean formation are provided. The cement composition includes a hydraulic cement, lightweight beads, and a desegregating agent for inhibiting segregation of the beads. The lightweight beads may be, for example, cenospheres, glass spheres, and ceramic spheres. The desegregating agent comprises a particulate substrate such as precipitated silica. It also comprises a polar molecule producing chemical disposed on the particulate substrate. Preferably, the polar molecule producing chemical is absorbed on the particulate substrate. The polar molecule producing chemical comprises at least one of a polar molecule producing acid such as glacial acetic acid, a salt of such an acid, and an acid anhydride. The method of cementing includes forming a pumpable slurry using the cement composition, pumping the slurry into a subterranean formation, and allowing the slurry to set.

대표청구항 ▼

What is claimed is: 1. A dry cement composition comprising: a dry cement; lightweight beads; and a desegregating agent for inhibiting segregation of the beads in the dry cement; wherein the desegregating agent comprises a particulate substrate and a polar molecule producing chemical disposed on the

What is claimed is: 1. A dry cement composition comprising: a dry cement; lightweight beads; and a desegregating agent for inhibiting segregation of the beads in the dry cement; wherein the desegregating agent comprises a particulate substrate and a polar molecule producing chemical disposed on the particulate substrate. 2. The cement composition of claim 1 wherein the polar molecule producing chemical comprises at least one of a polar molecule producing acid, a salt of the polar molecule producing acid, and an acid anhydride. 3. The cement composition of claim 1 wherein the particulate substrate is selected from the group consisting of precipitated silica, zeolite, talcum, diatomaceous earth, fuller's earth, and combinations thereof. 4. The cement composition of claim 2 wherein the polar molecule producing acid is an organic acid. 5. The cement composition of claim 2 wherein the polar molecule producing acid is selected from the group consisting of an acetic acid, an alkyl carboxylic acid, an alkene caiboxylic acid, sulfonic acid, and combinations thereof. 6. The cement composition of claim 2 wherein the acid anhydride is selected from the group consisting of sulfur dioxide, carbon dioxide, sulfur trioxide, nitrogen oxide, carboxylic acid anhydride, and combinations thereof. 7. The cement composition of claim 1 wherein the polar molecule producing chemical is glacial acetic acid, and wherein the particulate substrate is precipitated silica. 8. The cement composition of claim 1 wherein the polar molecule producing chemical is absorbed on the particulate substrate. 9. The cement composition of claim 1 wherein the beads are selected from the group consisting of cenospheres, glass spheres, ceramic spheres, and combinations thereof. 10. The cement composition of claim 1 wherein a weight ratio of the particulate substrate to the polar molecule producing chemical ranges from about 90:10 to about 10:90. 11. The cement composition of claim 1 wherein a weight ratio of the particulate substrate to the polar molecule producing chemical ranges from about 75:25 to about 25:75. 12. The cement composition of claim 1 wherein an amount of the desegregating agent in the cement composition ranges from about 0.01% to about 1.0% by weight of the cement. 13. The cement composition of claim 1 wherein an amount of the desegregating agent in the cement composition ranges from about 0.02% to about 0.5% by weight of the cement. 14. The cement composition of claim 1 wherein an amount of the desegregating agent in the cement composition ranges from about 0.03% to about 0.2% by weight of the cement. 15. The cement composition of claim 1 further comprising an amount of water sufficient to form a pumpable slurry.