Unlocking Offshore Brownfield's Oil Reserves: A Pioneering Approach with Acid Stimulation and Diversion Methods - Insights from the Gulf of Suez

Abstract

Abstract Handling the complexities of carbonate formations poses significant challenges in boosting oil production, especially in offshore brownfields dealing with water breakthroughs in commingled completions. While the commonly used mechanical diversion with straddle packers ensures effective zonal coverage and selective matrix acidizing treatment, it's important to note that these methods are more expensive than chemical diverters. This paper outlines a comprehensive strategy for enhancing production in such demanding scenarios. The approach considers various factors, including addressing the root causes of water breakthroughs, formulating appropriate acid chemicals, selecting effective chemical diversion methods, and optimizing the overall process execution. To illustrate the application of this approach, three candidates from the Gulf of Suez Basin, a complex and heterogeneous region in the Eastern Desert of Egypt with carbonate reservoirs, are examined as case studies. A viscous pill underwent laboratory testing before transitioning to field applications. This pill was designed to temporarily isolate fractures or fissure networks, diverting the primary treatment away from water and/or thief zones before the acid treatment. The results of this innovative chemical diversion technique demonstrate a remarkable four-fold increase in well productivity and a reduction in water cuts. This paper introduces the workflow and laboratory test results of a purpose-built acid and diversion technique explicitly tailored for fractured and watered-out carbonate reservoirs. Furthermore, it shares valuable insights and practical guidelines from the lessons learned while applying these methods, providing valuable guidance for future cases with similar challenges.