Patent ID: 8691737

Claim:
A consolidating spacer fluid for separating a drilling fluid and a cement composition in a well bore, comprising: water in an amount of about 15% to about 95% by weight of the spacer fluid; cement kiln dust; at least one additive selected from the group consisting of gypsum, bentonite, hydroxyethyl cellulose, sodium silicate, a hollow microsphere, gilsonite, perlite, a gas, an organic polymer, a biopolymer, latex, ground rubber, a surfactant, crystalline silica, amorphous silica, silica flour, fumed silica, nano-clay, salt, fiber, hydratable clay, rice husk ash, micro-fine cement, metakaolin, zeolite, shale, pumicite, Portland cement, Portland cement interground with pumice, barite, slag, lime, and any combination thereof; fly ash in an amount of about 1% to about 60% by weight of the spacer fluid; and a free water control additive in an amount of about 0.1% to about 16% by weight of the spacer fluid; wherein the consolidating spacer fluid has a zero gel time of about 4 hours or less under predetermined well bore conditions, wherein the consolidating spacer fluid is disposed in the well bore between the drilling fluid and the cement composition.