Prediction of Production in Oil Reservoirs by Considering Change in Number of Production Wells

Abstract Decline curve analysis (DCA) is a traditional method for production prediction, which is still being used today because of its simplicity. However, DCA methods have limitations in many cases when applied to entire reservoirs. Such cases include variation in production conditions and change in the number of injection and production wells. In this study, we focused on the latter problem, change in the number of production wells. Obviously, there would be a significant oil production boost during a specific time period if more oil wells are drilled. The traditional DCA approach cannot match the increase in oil production due to the increase in the number of oil production wells. We have developed a method to match and predict the oil production of entire reservoirs by considering the change in the number of production wells. The main idea of this new approach came from the concept of effective wells. We applied this new approach in several sandstone oil reservoirs with different permeabilities. Satisfactory results were obtained. Comparison with the existing models (exponential, hyperbolic model, and harmonic models) was made and the results showed the new approach had the best fit to the production history in the cases studied.