Which EOR method uses gases that expand in a reservoir and push additional oil to the production well bore?

Which EOR method uses gases that expand in a reservoir and push additional oil to the production well bore?

• A. CO2 Injection
• B. Natural Gas
• C. Nitrogen
• D. Gas Injection

Answer: (D)

Gas injection works by introducing a gas into the reservoir to create a driving force that displaces oil toward the production wells. The gas is compressible, so as it flows through the pore spaces and the reservoir pressure drops, the gas expands. This expansion pushes additional oil ahead of it, helping to sweep oil toward the wellbore and sustain production. Different gases—such as CO2, natural gas, or nitrogen—can be used in this approach, but the mechanism described—gas expansion creating a pushing effect to mobilize and move oil—is the defining feature of the gas injection method.

Gas injection works by introducing a gas into the reservoir to create a driving force that displaces oil toward the production wells. The gas is compressible, so as it flows through the pore spaces and the reservoir pressure drops, the gas expands. This expansion pushes additional oil ahead of it, helping to sweep oil toward the wellbore and sustain production. Different gases—such as CO2, natural gas, or nitrogen—can be used in this approach, but the mechanism described—gas expansion creating a pushing effect to mobilize and move oil—is the defining feature of the gas injection method.