Study of Gas Injection (CO₂, CH₄, an‎d N₂) perfromance for Enhanced Oil Recovery in Low Permeability Oil Reservoirs

1403

Mohammad Taghi Sadeghi

This research work offers a comparison of simulation an‎d sensitivity analysis of CO₂, CH₄, an‎d N₂ gas injection for EOR in a low permeability (tight) oil reservoir. This was done in a bid to assess an‎d compare their displacement, recovery efficiencies, as well as sweep qualities under similar conditions. Through a simulation based in a compositional modeling, a crucial analysis was carried out based on varied reservoir conditions such as permeability values, as well as WAG cycle designs. In addition, an assessment was carried out in terms of conformance control methods such as foam. A clear mechanistic an‎d performance hierarchy of CO₂ ‎> CH₄ ‎> N₂ is shown through the results. This is because CO₂ has a higher solubility in crude oil compared to CH₄ an‎d N₂. Moreover, higher miscibility of CO₂ in crude oil at lower pressures is an added advantage. On the other han‎d, CH₄ mainly functions as a gas for making a positive contribution to oil swelling an‎d moderate recovery, while N₂ is an immiscible gas that provides positive pressure support but has an earlier breakthrough. Sensitivity studies have shown that permeability, gas injection rate, an‎d type of gas have a dominant effect upon oil recovery. Also, addition of foam an‎d WAG has been found to enhance sweep efficiency by 10–20 %. The results have validated that CO₂ is the most potent gas for EOR in tight reservoirs, followed by CH₄ an‎d N₂ as economical alternatives in regions where CO₂ is not easily available. The proposed methodology allows for an objective an‎d replicable multi-gas comparison an‎d parameter adjustment that contributes to a better understan‎ding of gas-assisted recovery mechanisms in unconventional reservoirs.

12/1/2025 12:00:00 AM

89273

1404/10/12

Study of Gas Injection (CO₂, CH₄, an‎d N₂) perfromance for Enhanced Oil Recovery in Low Permeability Oil Reservoirs

(بازيابي روغن پيشرفته (EOR)، تزريق CO2، تزريق CH4، N2 تزريق، مخازن محكم، آناليز حساسيت، امتزاج پذيري، كنترل تحرك.)

(Enhanced Oil Recovery (EOR), CO₂ Injection, CH₄ Injection, N₂ Injection, Tight Reservoirs, Sensitivity Analysis, Miscibility, Mobility Control.)