Comprehensive evaluation of water breakthrough with a novel method to estimate water production

Produced water is inevitable in the life span of a reservoir despite the challenges associated with it. To make an informed decision on economic and engineering design, it is essential to establish post water breakthrough trend to predict water production and to design surface facilities to handle the volume of water that will be produced. Several correlations and models have been proposed in the literature; however, each of the models could solve the problem from which it was derived. Most of the traditional models represent water cut as a function of cumulative oil production or time which is only achievable when accurate water cuts are available. This paper analysis post water breakthrough performance using empirical models. In this proposed method, the water cut (WC) was redefined and plotted against the oil flow rate (Qo). Different models were developed to capture the trends of the plotted graph. It is interesting to note that during water breakthrough, there exist exponential, hyperbolic and harmonic increase in water production throughout the reservoir life span. The model was validated with producing field data and has proven to be robust and can be a reliable tool for estimating water production. The newly developed model in this paper offers an advantage of predicting the corresponding WC at any given Qo and bottom hole pressure.