Innovative Approach to Enhance Reservoir Sweeping Efficiency Using Open Hole Swellable Packers in Gas Injector to Isolate Undesired Reservoir Section in Carbonate Reservoir Field of Abu Dhabi, UAE

Abstract

Gas Injector Well is part of the project to improve the pressure communication between peripheral gas injectors and nearby producers in the Northern Part of Unit G WAG Patterns. This well was injecting gas only to upper part of Unit G reservoir based on the PLT and TGT results. Based on the study using tracer chemical injection, this upper Unit G reservoir was found to be in connecting with another nearby different reservoir. The initial plan was to re-horizontalize the well and place injector in the proper reservoir, later this was changed and revised to use this innovation technology by installing blank liner with isolating packer to isolate the upper part of Unit G reservoir and let the lower part of open-hole remained open and connected to the required layer of reservoir. After extensive discussion with vendors and performing simulation runs, finally agreed to run this kind of swell packer. Vendor custom designed this kind of innovative packer at their USA facility and transported to ADNOC Onshore yard just before the execution phase. First run the swell packer on blank pipe and placed it at desired depth in the open hole, later run upper completions and sting into the top packer of lower completion. This way, we were able to inject gas into the lower part of reservoir Unit-G only, whereas the upper part was remained isolated completely. Using this technique saved company additional 2 million and extra time for re-horizontalization.