Oil recovery process
US4544033A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1984 |
| Grant date | Oct 1, 1985 |
| Priority date | — |
| Expiry date | Mar 23, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/584
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process for recovering oil from an oil-bearing subterranean reservoir penetrated by at least one injection well and at least one production well which comprises the steps of: PA0 (1) injecting into the oil-bearing subterranean reservoir through the injection well a first injecting fluid consisting essentially of (a) 1% to 30% by weight of an internal olefin sulfonate having 10 to 26 carbon atoms and a disulfonate content of 20% by weight or less, (b) 0.1% to 20% by weight of a cosurfactant, and (c) a brine; PA0 (2) injecting, as a second injecting fluid, an aqueous polymer solution having a viscosity higher than that of the first injecting fluid into the oil-bearing subterranean reservoir; and PA0 (3) recovering oil replaced with the first and second injecting fluids through the production well. This process can recover oil from subterranean reservoirs at a high oil recovery efficiency without destroying a micro-emulsion during sweeping in the subterranean reservoir even when the salt concentration of the formation water is widely changed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.