ALKALINE WATER FLOODING PROCESSES FOR ENHANCED OIL RECOVERY IN CARBONATES

摘要

A method for extracting hydrocarbons from a carbonate reservoir in a formation, the method includes: injecting an aqueous conditioning slug having a primary reducing agent into the carbonate reservoir; injecting an aqueous main slug having an alkalinity agent and a secondary reducing agent into the carbonate reservoir to treat the carbonate reservoir and surface of the formation to reduce interfacial tension and alter wettability of the surface of the formation towards water-wet; injecting an aqueous buffering slug into the carbonate reservoir, the aqueous buffering slug having a tertiary reducing agent to treat the carbonate reservoir and surface of the formation to maintain altered wettability; wherein the primary reducing agent, secondary reducing agent, and tertiary reducing agent are inorganic sodium salts selected from the group consisting of: sodium sulfate, trisodium phosphate, sodium tetraborate, sodium iodide, and combinations of the same; and injecting a displacing fluid to drive the hydrocarbons in the carbonate reservoir toward an extraction well.