Abstract
A foamable drilling fluid is provided which includes an aqueous solvent; a surfactant; and a polysaccharide preferably derived from a galactomannan gum. The foamed drilling fluid includes a liquid phase consisting of the aqueous solvent, polysaccharide and surfactant, and a gas phase of air, nitrogen, natural gas, CO2 and mixtures thereof. The drilling fluid is stable in the presence of crude oil and salt and environmentally friendly.
| Original language | English |
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| Patent number | US6800592 |
| Filing date | 28/08/01 |
| Publication status | Published - 5 Oct 2004 |