Oil reservoir permeability control
US4776398A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1987 |
| Grant date | Oct 11, 1988 |
| Priority date | — |
| Expiry date | Apr 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/935
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The permeability of a subterranean oil-bearing formation is controlled by the injection of an aqueous solution of a cross-linked block copolymer containing polar and non-polar segments, with the polar segments generally making up at least 50 percent, usually 60 to 99 percent, of the copolymer. The polar segments are derived from an alkylene oxide and the non-polar segments from styrene or an alkyl styrene either by itself or with a diene. The copolymers are cross-linked with an amino resin or a combination of a phenolic and a water-dispersible aldehyde component. The resulting copolymer gels are stable at low pH conditions, such as those of CO.sub.2 flood conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.