Otimização em malha fechada do desenvolvimento de campos de petróleo sob incertezas geológicas

Abstract

The objective of this work was to analyze the economic gains, in terms of Net Present Value (NPV), of the successive adjustments in the development plan (DP) of an oil field as new information was made available by drilling and production of the wells. The closed-loop optimization of the development of oil fields under geological uncertainties, also referred as Closed Loop Field Development (CLFD) was applied in the UNISIM-I benchmark model, based on the field of Namorado, of the Brazilian offshore. The CLFD has cyclically used the steps of history matching, selection of representative models and optimization of DP in the ensemble of uncertain models, elaborated with a limited amount of initial information. Production data and well logs used in the cycles were obtained in a reference model that reproduces the behavior of the real reservoir. The comparison between the response of the reference model when using the DP generated by the methodology and an initial DP was used to compare the gains. The results showed a 29.0 % increase in NPV when applying the methodology compared to the initial PD. The CLFD was also able to improve decision making by systematically increasing the NPV of the set of uncertain models. Although the computational costs involved were high, they did not impose a restriction on the use of the methodology. The use of DCMF brought consistent economic gains and is, therefore, applicable in real cases.