Abstract
The paper describes the best practices and the excellence of Well-Reservoir-Facility Management (WRFM) in one of the Oil Assets located in the South in Sultanate of Oman. The asset consists of 35 main oil fields where 17 fields are under waterflood. These fields are in a mature stage of development within Permian Gharif formation reservoirs. Gharif formations are stacked reservoirs which basically are complex and heterogeneous reservoir Waterflood management in this complex formation is highly challenging, particularly due to water-front conformance issues that impact both vertical and horizontal efficiencies.
The surface facilities consist of five geographically distributed gathering and processing stations, which pose additional challenges. Besides the complex reservoirs, there are other four main challenges: the historical high voidage volumes with poor waterflood performance, the aging wells and facilities, the facilities gas and water handling constraints, and the injected water availability.
An integrated Well-Reservoir-Facility Management (WRFM) Framework was developed to maximize Lifecyle value and meet or exceed production, reserves, and cost targets despite the existing challenges. The framework outlines WRFM strategy, operational philosophy, Gap-to-Potential (GtP) plan and tools, key uncertainties coupled with surveillance plan, key risks coupled with new technologies plan, budget planning and control, resources & capabilities, workflows & decisions. All of these were managed using the Continuous Improvement Fundamentals (CIF).
The WRFM practices and approach followed in the Asset under study has resulted in remarkable achievements in different fronts
Injecting at historical rates has resulted in maintaining non further activities (NFA) and an increase in reserves. Reservoir Operating compliance is maintained above target around 90%. Well production optimization from Water injection gain reached 30% of base production with low Unit Technical Cost (UTC) and it is the highest in the south and able to reach the top quartile in optimization gains in company level. The water availability have been improved to 98%, leading to an incremental 25% of cashflow above the expected cashflow and reaching the lowest deferment ever and lowest ESP pumps failure. The flare has been reduced by more than 30%. The case study describes a novel approach on how to manage a complex brown field with ageing wells and constrained facilities.
