Drilling fluid additive composition and water-based drilling fluid suitable for high-pressure plugging
US9890318B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2017 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Jun 28, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/12
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to the well drilling field in petroleum industry, in particular to a drilling fluid additive composition and a water-based drilling fluid suitable for high pressure plugging while drilling. The composition contains a bridging agent, a nano-plugging agent, a rheological modifier, a bionic wall bracing agent, and a bionic shale inhibitor, wherein, the bridging agent is a weak-crosslinked copolymer, in which the content of cross-linker structures is 0.1-1 wt. %; the nano-plugging agent is modified nanometer silicon dioxide particles; the rheological modifier is a dimer acid-organic amine copolymer; and the bionic wall bracing agent is carboxymethyl chitosan with a dopamine-derived base group grafted on its main chain. With a synergistic effect among the bridging agent, the nano-plugging agent, the rheological modifier, the bionic wall bracing agent, and the bionic shale inhibitor in the composition provided in the present invention, the water-based drilling fluid containing the composition as additive can attains an excellent plugging effect in a drilling process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.