Potential Application of CO₂ for Enhanced Condensate Recovery Combined with Geological Storage in the Depleted Gas-Condensate Reservoirs

CO₂ emissions are considered to be the main contributor to global warming and climate change. One of the ways reducing the emissions to atmosphere is a proper capture and further geological storage of the carbon dioxide. In the oil industry, CO₂ is used as one of the injection agents to displace oil and enhance its recovery. Due to the low multi-contact miscibility pressure between CO₂ and hydrocarbons, fully miscible condition is quickly reached, leading to efficient displacement and high recovery factors. The utilization of the depleted gas fields for CO₂ storage, however, is considered as the option that is more expensive compared to oil field, since the enhanced recovery of gas with CO₂ is not effective. For this reason, our study considers the potential use of CO₂ EOR in depleted gas-condensate fields. This potential is evaluated by performing numerical simulations for the typical-size gascondensate reservoirs with no active aquifer, in order to estimate both the storage efficiency and the additional oil recovery from condensed C₅₊ hydrocarbon fractions, that otherwise will be never recovered and lost in the reservoir. Obtained results indicate significant potential for CO₂ storage and additional condensate recovery from the typical gas-condensate field of Eastern Ukraine.