Stabilized colloidal and colloidal-like systems
View Patent ↗The present invention generally relates to improved compositions comprising stabilized colloidal or colloidal-like phases (e.g., emulsions, aphrons) and methods of using those compositions. The compositions generally comprise an aqueous continuous phase, one or more viscosifiers, one or more surfactants, aphrons and one or more Aphron Stabilizers. The compositions of the present invention possess aphrons with significantly increased half-life and enhanced ability to seal permeable formations, and are capable of being used in high pressure applications.
1. A drilling or servicing fluid composition comprising:
an aqueous liquid as the continuous phase;
one or more surfactants;
aphrons; and
one or more aphron stabilizers, wherein at least one said aphron stabilizer comprises polyvinyl alcohol, and the composition comprises from about 0.05% to about 2% by weight aphron stabilizer.
2. The composition according to claim 1 further comprising one or more viscosifiers.
3. The composition according to claim 1 wherein the aphrons have an average half-life of greater than or equal to about 20 hours.
4. The composition according to claim 1 wherein the aphrons have an average half life of greater than or equal to about 75 hours.
5. The composition according to claim 1 wherein the aphrons have an average half-life of greater than or equal to about 150 hours.
6. The composition according to claim 1 wherein the aphrons have an average half-life of greater than or equal to about 200 hours.