An Environmental-Friendly Amphiphilic Molecule for Simultaneously Improving CO₂ Geological Storage and Utilization

Area of Science:

• Petroleum Engineering
• Geological Storage
• Enhanced Oil Recovery

Background:

• CO2 injection is key for geological storage and resource recovery in low-permeability reservoirs.
• Conventional CO2 flooding faces limitations due to substantial CO2 coproduction, reducing storage efficiency.
• Need for improved methods to enhance CO2 solubility, reduce interfacial tension, and manage wettability in saline conditions.

Purpose of the Study:

• To introduce a natural amphiphilic molecule (ARGS) for enhanced oil recovery (EOR) and CO2 storage.
• To investigate ARGS's effect on CO2-oil-water-rock interfacial and mass-transfer properties under saline conditions.
• To evaluate ARGS's potential for simultaneous oil recovery increase and efficient CO2 geological storage.

Main Methods:

• Utilized a natural amphiphilic molecule (ARGS) in CO2 injection processes.
• Assessed ARGS's impact on CO2 solubility, interfacial tension, and wettability under high-salinity conditions.
• Analyzed oil displacement efficiency in micro- and mesopores and CO2 storage mechanisms (dissolved and trapped).

Main Results:

• Achieved a 9.7% increase in oil recovery compared to conventional CO2-EOR, with up to 85% CO2 storage ratio.
• ARGS increased CO2 solubility by 4-fold and reduced CO2-formation water interfacial tension by 36% in high-salinity water.
• Shifted pore-surface wettability to water-wet, increasing oil displacement efficiency by 10%-15% and CO2 flow resistance.

Conclusions:

• ARGS effectively enhances both oil recovery and CO2 geological storage in low-permeability reservoirs.
• ARGS improves CO2 solubility and wettability, promoting dissolved CO2 storage (up to 70%) and trapped CO2.
• Presents an environmentally friendly approach for efficient CO2 utilization and storage in challenging geological formations.