abstract |
Methods of cementing and low density foamed cement compositions therefor are disclosed. A low density foamed cement composition of the invention comprises fly ash comprising calcium oxide or calcium hydroxide, water present in an amount sufficient to form a slurry, a foaming and foam stabilizing surfactant or a mixture of surfactants present in an amount sufficient to facilitate foam and stabilize the foamed cement composition, and sufficient gas to foam the foamed cement composition. |