Carbon dioxide foamed fluids
US7291651B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2004 |
| Grant date | Nov 6, 2007 |
| Priority date | — |
| Expiry date | Sep 2, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/904
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An aqueous viscoelastic surfactant (VES) fluid foamed or energized with carbon dioxide, in which the VES is more compatible with the carbon dioxide, is made by the addition of one or more than one synergistic co-surfactant. The synergist co-surfactant includes quaternary amines and ethoxylated carboxylates having a hydrophobic chain shorter than the hydrophobic chain of the VES. Improved compatibility is evidenced for a given surfactant concentration either by formation and maintenance of a foam under conditions at which the foam could not otherwise have been formed or maintained, or by either higher viscosity of the foamed fluid at a given temperature or longer foam life at a given temperature or a higher temperature at which useful fluid viscosity can be generated or maintained for a useful time. The aqueous carbon dioxide foamed fluids may be used in acidizing, acid fracturing, gravel packing, diversion, and well cleanout.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.