EnhancedOilRecoveryVerfahren

Enhanced Oil Recovery (EOR), also known as improved oil recovery, refers to a variety of techniques used to increase the amount of crude oil extracted from an oil field. After primary recovery methods (natural pressure) and secondary recovery methods (water or gas injection) have been utilized, a significant amount of oil often remains trapped in the reservoir. EOR methods are implemented to mobilize this remaining oil.

There are three main categories of EOR: thermal recovery, gas injection, and chemical injection. Thermal recovery involves injecting heat into the reservoir to reduce the viscosity of heavy oil, making it flow more easily. Steam injection is the most common thermal method. Gas injection methods involve injecting gases like carbon dioxide (CO2) or nitrogen into the reservoir. These gases can mix with the oil, reducing its viscosity and swelling it, or they can form a miscible front that pushes the oil towards production wells. Chemical injection involves introducing chemicals, such as polymers, surfactants, or alkalis, into the reservoir. Polymers increase the viscosity of injected water, improving sweep efficiency. Surfactants reduce interfacial tension between oil and water, helping to detach oil droplets from the rock. Alkalis can react with oil to create in-situ surfactants.

The choice of EOR method depends on various factors, including the type of crude oil, reservoir characteristics (rock properties, temperature, pressure), and economic considerations. EOR techniques are crucial for maximizing oil production from mature fields and can significantly extend the productive life of an oil reservoir.