The Dynamics of Commingled Production

Abstract

Commingled production strategies have been applied successfully worldwide because of the advantages they provide in terms of cost effectiveness and completion simplicity. However, a commingled production approach raises several challenges for reservoir management. The behavior of a commingled well is much more complicated than that of a single-layer well. However, there is little knowledge or experience sharing documented in the literature. The objectives of this study are to comprehensively review reservoir engineering knowledge and performance of commingled wells, and to propose tools for reservoir management decisions. This study summarizes the current knowledge of decline curve analysis (DCA) and material balance equations (MBE) for commingled production available in the literature, and reviews lessons learned from production logging and water shut-off lookback studies in Gulf of Thailand operations. Based on this information, this study proposes the use of a “risky-sand matrix”, of perforation best practices, and of commingled well models. Through these approaches, petroleum and reservoir engineers will be better able to understand the performance characteristics of commingled wells and will be in a position to make better reservoir management decisions.