Double emulsion based drilling fluids
US6793025B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 2002 |
| Grant date | Sep 21, 2004 |
| Priority date | — |
| Expiry date | Jun 17, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/904
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method of electrically logging subterranean wells using a conductive double emulsion fluid includes a miscible combination of an oleaginous fluid, an emulsifier capable of forming a microemulsion, an emulsifier capable of forming an invert emulsion, and an electrolytic salt. A microemulsion is the continuous phase of an invert emulsion. The electrolytic salt or brine of the salt is present in a concentration sufficient to permit the electrical logging of the subterranean well. The fluid may additionally contain a polar organic solvent and a carbon dioxide buffer. The polar organic solvent may be an oil soluble glycol or glycol ether such as ethylene glycol, diethylene glycol, propylene glycol, polypropylene glycol, and the like. The electrolytic salt preferably is a quaternary amine salt having the formula: wherein R is an alkyl having 8 to 18 carbon atoms, R′ is 2 to 6 carbon atoms alkyl group, B is hydrogen, oxyalkyl having 1 to 4 carbon atoms or alkyl having 1 to 4 carbon atoms, A is hydrogen or alkyl with 1 to 4 carbon atoms, x+y=1 to 15, z is 0 to 3, and M− is a counter anion; or combinations thereof. In such instances the quaternary amine salt serves both as the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.