Feasibility Study of Gas-Based EOR Processes in a North Sea Oil Reservoir

This work investigates the potential standalone field re-development of a small North Sea oil field through<br>the deployment of a gas injection process that utilizes the produced gas as the key enhanced oil recovery<br>(EOR) agent. A field-sector, compositional simulation model is constructed to evaluate and compare the<br>most promising gas-based EOR techniques such as continuous gas injection, water alternating gas and<br>simultaneous water and gas injection processes against water injection. Sensitivity studies are conducted to<br>optimize the conditions/parameters of the selected EOR technique and practical issues that can influence<br>oil recovery factors are evaluated for a potential pilot or field-wide scale implementation.<br>The results indicate that the implementation of a Simultaneous Water And Gas (SWAG) EOR injection<br>process that makes use of the field produced gas and having undergone a thorough and field-wide<br>optimization of operational parameters (produced gas availability, fluids injection rate, injection water-gas<br>ratio, production and injection wells BHP, fluids injection scheme, etc.) as well as a careful investigation<br>of potential well interventions to increase oil production (selective re-perforation of existing wells,<br>possible shutoff of excess water, etc.) could be a viable EOR technique for re-developing this asset.