Preparation of viscosifiers for zinc salt workover and completion brines
US4415463A · kind A · utility
22Cited by
8References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1981 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | Jun 26, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/925
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Viscosifiers for addition to high zinc salt brines, used as oil well workover and completion fluids, are prepared from natural polysaccharide gums by treatment with a basic nitrogen reagent, such as a quaternary ammonium compound, hexamethylene tetramine, or dimethylol urea. The treated viscosifiers have improved dispersibility and give increased viscosity effects in the brines. Preferably, the viscosifiers are prepared from carrageenan or locust bean gums.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.