Drilling fluid
US6544933B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1998 |
| Grant date | Apr 8, 2003 |
| Priority date | — |
| Expiry date | Jul 13, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/12
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A water-based drilling fluid (WBM) comprises as additive a reaction product of a polyhydroxyalkane and alkylene oxide. The polyhydroxyalkane is desirably based on a monosacchoride, and is preferably sorbitol. The alkylene oxide may comprise ethylene oxide (EO), propylene oxide (PO) and/or butylene oxide (BO). Good results have been obtained with additives including Sorbitol+18EO, Sorbitol+9PO, Sorbitol+4EO+6BO, Sorbitol+6EO+6BO, or Sorbitol+6BO. Drilling fluids in accordance with the invention have been found in laboratory tests to exhibit improved shale inhibition properties as compared with known polyol containing WBM, particularly in the absence of added potassium ions. This is environmentally advantageous.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.