Drilling fluids containing biodegradable organophilic clay
US7521399B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 25, 2005 |
| Grant date | Apr 21, 2009 |
| Priority date | — |
| Expiry date | Feb 18, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/145
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Drilling fluids are provided that comprise an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage. The quaternary ammonium surfactant may comprise a compound generally represented by the following formula:where M− is an anion such as a chloride, methyl sulfate, bromide, acetate, or iodide ion; R1 is an alkyl group such as a saturated hydrocarbon with 10 or more carbons; R2, R3, and R4 are the same or different alkyl groups such as a methyl, ethyl, or benzyl group, and x is greater than or equal to 1. The organophilic clay treated in this manner is substantially biodegradable. In embodiments, the drilling fluids comprise the foregoing organophilic clay, an oil-based fluid and a weighting agent. In still embodiments, the drilling fluids comprise the foregoing organophilic clay, an invert emulsion, an emulsifier, and a weighting agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.