The present invention relates to foamed cement slurries, additives and methods.
A foamed cement slurry of the invention comprises a hydraulic cement, sufficient
water to form a slurry, sufficient gas to form a foam and an environmentally benign
foaming and stabilizing additive comprising a mixture of an ammonium salt of an
alkyl ether sulfate surfactant, a cocoamidopropyl hydroxysultaine surfactant, a
cocoamidopropyl dimethylamine oxide surfactant, sodium chloride and water.