A technical evaluation of a CO2 flood for EOR benefits in the Cooper Basin, South Australia

Abstract

<jats:title>Abstract</jats:title> <jats:p>This study evaluates reservoir and reservoir fluid parameters relevant to CO2 flooding to enhance hydrocarbon recovery from a Cooper Basin oilfield (Field A), located in South Australia.</jats:p> <jats:p>Field A is a tight (k&amp;lt;1mD) sandstone reservoir containing volatile and low viscosity oil. CO2 could be separated from raw gas produced from a nearby gas field (Field B) or made available from a gas processing facility located some 60km from Field A. The costs of preconditioning the CO2 to suitable composition and pressures are known to be high, but have not been considered in this study.</jats:p> <jats:p>Laboratory experiments were conducted using both pure carbon dioxide and a synthesized gas derived from Field B gas, consisting mainly of CO2 and methane. The increase in oil recovery as a function of pressure was determined, which would be a basis for selection of injection pressure. In addition, minimum miscibility pressures using both CO2 and the synthetic gas mixture and the utilization factor of CO2 injected to oil produced were also determined.</jats:p>