Oil recovery from underground reservoirs is never straightforward. Once the natural pressure subsides, a significant volume of crude oil remains trapped. This is where specialized chemicals for oil recovery become essential. These chemicals improve extraction efficiency, especially during enhanced oil recovery (EOR) processes, by modifying the behavior of fluids within the reservoir.
Understanding the Challenges in Oil Recovery
The oil production process typically occurs in three stages: primary, secondary, and tertiary (also known as EOR). While the first two stages recover about 30–40% of the oil, a substantial amount stays locked in porous rock formations. To extract more, operators turn to chemical EOR techniques.
The challenge lies in overcoming reservoir resistance and the oil’s tendency to adhere to rock surfaces. Without assistance, this oil remains inaccessible, reducing the overall yield and increasing operational costs.
Surfactants as the Backbone of Chemical EOR
Surfactants are among the most widely used specialized chemicals in oil recovery. They reduce interfacial tension between oil and water, allowing trapped oil to move more freely through porous rock. This process, known as surfactant flooding, enables oil to detach from reservoir rock and flow toward the production well.
How Surfactants Work
Surfactants have both hydrophilic and hydrophobic parts. In oilfield applications, they lower surface and interfacial tensions and modify wettability — shifting rock surfaces from oil-wet to water-wet. This change helps displace the residual oil, which would otherwise remain bound to the rock matrix.
The selection of surfactants depends on reservoir conditions such as salinity, temperature, and pressure. Common types include:
Formulations may combine multiple surfactant types to maximize performance while minimizing cost and environmental impact.
While surfactants play a lead role, other chemicals also contribute to effective EOR operations:
Demulsifiers for Crude Oil Separation
Once oil reaches the surface, it often forms stable emulsions with water. Demulsifiers break these emulsions, allowing for efficient separation of oil and water. This step is vital for ensuring product purity and preventing corrosion or damage in downstream equipment.
Polymers for Mobility Control
Polymers such as partially hydrolyzed polyacrylamide (HPAM) increase water viscosity. This balances the mobility ratio between injected water and oil, pushing the oil toward the wellbore with more force and less channeling.
The strategic use of chemicals in EOR provides clear operational benefits:
These chemicals enable operators to extract more oil with fewer wells, less energy input, and lower environmental disruption.
Choosing the right surfactant system is a balance of performance, cost, and reservoir compatibility. Key considerations include:
A laboratory screening followed by core flood testing is standard practice before field implementation. This ensures that the chemical system is tailored to the specific field conditions.
The Unitop Advantage
At Unitop Chemicals, we develop and supply specialized surfactants and chemical formulations tailored for oil recovery applications. Our solutions are optimized through rigorous lab testing and formulated to deliver reliable performance under challenging field conditions.
Whether you’re operating in conventional fields or pursuing tertiary recovery, our surfactant systems and demulsifiers help improve oil yield, process efficiency, and sustainability.
Advanced surfactants and supporting chemical agents play a critical role in enhanced oil recovery. As oilfields age and primary methods plateau, specialized chemicals for oil recovery become essential tools for maximizing production. With the right chemical strategy, operators can extend field life, lower costs, and extract more value from existing reserves.