Disclosed herein are cement compositions using set-delayed cement compositions in subterranean formations. The composition may comprise a set-delayed cement composition comprising pumice, hydrated lime, a cement set retarder, a synthetic smectite, and water.

Cement retarders are based on blends of lignosulfonate compounds, borate compounds and gluconate compounds. The compounds are present in certain ratios that allow the retarders to operate at temperatures and pressures up to and exceeding about 176 C. and 152 MPa. The retarders may also be provided in liquid form, improving their suitability for use at offshore well-site locations.

Cement retarders are based on blends of lignosulfonate compounds, borate compounds and gluconate compounds. The compounds are present in certain ratios that allow the retarders to operate at temperatures and pressures up to and exceeding about 176 C. and 152 MPa. The retarders may also be provided in liquid form, improving their suitability for use at offshore well-site locations.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. In one embodiment, a method of cementing in a subterranean formation is described. The method may comprise providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; activating the set-delayed cement composition with a liquid additive to produce an activated cement composition, wherein the liquid additive comprises a monovalent salt, a polyphosphate, a dispersant, and water; and allowing the activated cement composition to set.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. In one embodiment, a method of cementing in a subterranean formation is described. The method may comprise providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; activating the set-delayed cement composition with a liquid additive to produce an activated cement composition, wherein the liquid additive comprises a monovalent salt, a polyphosphate, a dispersant, and water; and allowing the activated cement composition to set.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. A method of cementing in a subterranean formation, may comprise providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder, activating the set-delayed cement composition with a cement set activator, wherein the cement set activator comprises at least one activator selected from the group consisting of nanosilica, a polyphosphate, and combinations thereof, introducing the set-delayed cement composition into a subterranean formation, and allowing the set-delayed cement composition to set in the subterranean formation.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. A method of cementing in a subterranean formation, may comprise providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder, activating the set-delayed cement composition with a cement set activator, wherein the cement set activator comprises at least one activator selected from the group consisting of nanosilica, a polyphosphate, and combinations thereof, introducing the set-delayed cement composition into a subterranean formation, and allowing the set-delayed cement composition to set in the subterranean formation.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.

Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.

A chemical additive for calcium sulphoaluminate-modified Portland cement comprises the following substances: (a) at least one alkanolamine borate; (b) at least one organic alcohol; and (c) at least one saccharide or a derivative thereof; and the substances and water are sequentially mixed and stirred to obtain the chemical additive for calcium sulphoaluminate-modified Portland cement. The chemical additive for calcium sulphoaluminate-modified Portland cement provided by the invention has better effects of regulating the setting time of the calcium sulphoaluminate-modified Portland cement and improving the 3d/28d strength increase rate, and also has a grinding aid effect when being added during grinding.