Method and materials to convert a drilling mud into a solid gel based lost circulation material
US10655050B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 2019 |
| Grant date | May 19, 2020 |
| Priority date | — |
| Expiry date | Feb 21, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/10
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method for controlling loss circulation. The method includes introducing into a wellbore a nanosilica drilling fluid comprising water and an alkaline nanosilica dispersion. The method further includes introducing into the nanosilica drilling fluid an amount of a chemical activator comprising a water soluble hydrolysable polyester to produce a convertible drilling mud where the convertible drilling mud has an initial pH between 8 and 11 upon formation. The method also includes allowing the chemical activator to hydrolyze to produce an acid and reduce the pH of the convertible drilling mud to less than a gel pH, thereby converting the convertible drilling mud into a solid gel lost circulation material. A convertible drilling mud operable to convert into a solid gel lost circulation material is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.