Chemical EOR Evaluation for GNPOC and PDOC Fields in Sudan

Qiang, Wang (CNPC Research Institute of Petroleum Exploration & Development) | Ming, Gao (CNPC Research Institute of Petroleum Exploration & Development) | Zhaoxia, Liu (CNPC Research Institute of Petroleum Exploration & Development) | Bakar, Mohamad Abu (PETRONAS) | Chong, Yeap Yeow (PETRONAS) | Adnan, Izwan B. (PETRONAS)

OnePetro 

The objective of this paper is to scope the Chemical EOR potential in both GNPOC and PDOC fields in Sudan. From the initial EOR screening, the most amenable EOR processes identified for both GNPOC and PDOC are mainly chemical and thermal EOR. Chemical EOR is the leading EOR process in GNPOC fields while thermal EOR is the leading EOR process in PDOC fields.

Chemical EOR evaluation was performed using Eclipse EOR black oil simulator. Simulations were performed on sector models constructed or extracted from full field models which have been conditioned to the current reservoir condition. The chemical input data was referenced mainly from Qing Hai oil field lab data which oil properties are similar to that of Sudan's. The chemical EOR evaluation encompass 3 different types of chemical processes; polymer flooding, surfactant-polymer (SP) flooding and alkaline-surfactant-polymer (ASP) flooding. Chemical EOR can potentially improve field recovery factor between 4-18% depending on the type of chemical EOR process. ASP flooding possess the highest potential with incremental oil recovery over waterflood ranging between 12%-18% followed by SP flooding and polymer flooding. ASP flooding is taken as the reference chemical process in this study as it as it represent the highest chemical potential.

The outcome of this study is believe to be helpful to successful planning of Chemical EOR applications in sudan.