Additive for increasing the density of an oil-based fluid and fluid comprising such additive
US7267291B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2003 |
| Grant date | Sep 11, 2007 |
| Priority date | — |
| Expiry date | Apr 6, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/906
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A wellbore fluid having an oleaginous phase and an additive for increasing the density of the wellbore fluid. The additive comprises solid colloidal particles coated with a dispersant during the comminution process of forming the particles. Exemplary starting materials for the colloidal particles include commonly known weighting agents as well as mixture and combinations thereof. The dispersant in one embodiment, is selected from carboxylic acids of molecular weight of at least 150 Daltons. Alternatively, the dispersant coating may be made of compounds including oleic acid, polybasic fatty acids, alkylbenzene sulfonic acids, alkane sulfonic acids, linear alpha-olefin sulfonic acid or the alkaline earth metal salts of any of the above acids, and phospholipids as well as mixtures and combinations of these compounds. In another embodiment the dispersant is a polyacrylate ester having an average molecular weight from about 10,000 Daltons to about 200,000 Daltons.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.