Use of Compositional Modelling in the Development Planning of Gbaran Field, Nigeria

Abstract Compositional simulation was applied in the development planning of Gbaran field in Nigeria. A major challenge of the study was to determine the optimal development and management strategy for maximising recovery of both oil and condensate, simultaneously. A full-field simulation model was constructed to accurately simulate the reservoir fluid phase behaviour, study the reservoir displacement and recovery mechanism and optimise the configuration and design of surface facilities. The reservoir fluid was adequately characterised using an 8-component Peng-Robinson equation-of-state model. The model was used to predict future reservoir performance under various developments and operating scenarios and to determine the optimum oil and condensate recoveries. The study showed that an integrated oil and condensate development strategy involving gas re-injection and partial cycling would lead to optimal oil and condensate recoveries of 63 % and 68 % respectively. Under natural depletion however, the recovery for oil would be 49 %, while condensate recovery would be relatively insignificant.