| 摘要 |
<p>F-2689 HIGH SWEEP EFFICIENCY STEAM DRIVE OIL RECOVERY METHOD In a steam flood oil recovery process wherein the oilcontaining formation has a natural brine salinity concentration within the range of 10 to 20% by weight, sweep efficiency is improved by injecting steam until steam breakthrough occurs at the production well after which a mixture of steam, a noncondensible gas, and a surfactant comprising a C12 alpha olefin sulfonate is injected into the formation. The C12 alpha olefin sulfonate forms a stable foam with the formation oil at formation conditions that reduces the permeability of the highly permeable steam swept zones thereby diverting the steam to other portions of the formation containing unswept oil. If the formation does not contain a natural brine salinity concentration when the salinity of the mixture of steam, noncondensible and surfactant is controlled to a concentration of about 10% by weight by adding a salt thereto.</p> |
