Cement set activators for set-delayed cement compositions and associated methods

A method of making an activated cement composition, the method comprising:

• providing a set-delayed cement composition comprising:
• water;
• pumice;
• hydrated lime;
• and
• a set retarder selected from the group consisting of diethylenetriaminepentamethylenephosphonate, nitrilotrismethylenetriphosphonate, methylene phosphonates, methylene phosphonic acid derivatives, and combinations thereof;
• storing the set-delayed cement composition in a pumpable fluid state for at least about one day;
• and
• adding a liquid activator to the set-delayed cement composition, wherein the liquid activator comprises water, a dispersant, a polymeric metaphosphate salt and monovalent salt.

An activated cement composition comprising:

• water;
• pumice;
• hydrated lime;
• a set retarder selected from the group consisting of diethylenetriaminepentamethylenephosphonate, nitrilotrismethylenetriphosphonate, methylene phosphonates, methylene phosphonic acid derivatives, and combinations thereof;
• and
• a liquid activator, wherein the liquid activator comprises water polymeric metaphosphate salt, a dispersant, and a monovalent salt.