Real-Time Production Surveillance Overcomes Challenges in Offshore Dual String Gaslift Wells in Baram Field, Malaysia

Abstract

PETRONAS and OVS Group team up to optimize gas-lift process in offshore dual string oil wells in Baram field, Malaysia. This paper outlines how the real-time production data and well model approach help to overcome the challenges faced in dual string gaslift wells and improve their performance. Challenges To determine the injected gas allocation factor in dual-string wells when both strings are producing. To determine the well inflow performance with limited or no reservoir information such as permeability, drainage area, skin etc. for multiple completions. To improve the well and field performance in absence of daily measured flow rates. To diagnose high producing GOR wells to improve the gaslift performance. Methodology Gas Allocation method is developed to compute gas injection rate in each string based on welltests. Composite IPR is built at the solution node (Figure: 1.0) where fluids from all producing completions are commingled in tubing and nodal analysis is performed. Well-model-based Virtual Meter (VM) approach is used to estimate the flow rates and improve the well and field performance. Gas lift diagnostic is used to identify gas-lift performance issues. Results, Observations, and Conclusions:Integration of databases helped to find out missing/wrong data in well tests and prioritize well tests which are overdue.Ensuring the consistency of Total GOR at reservoir and well level improved the inflow performance for production surveillance, optimization and forecast.VM enhanced the surveillance and understanding of wells, highlighted opportunities and improved the allocation method.Recommendations were made to review production strategy due to gas conning or gaslift design to improve the production and gaslift performance in high producing GOR wells. Significance of Subject Matter:When limited or no downhole information is available, pressure gradients analysis in both casing and tubing helps to estimate the gas injection rate using surface measurements.In case of multipoint injection (Figure: 2.0), well performance is carried out based on deepest injection point if it is possible. Necessary recommendations are made to avoid multipoint injection for efficient gas lift operation. Application It can be applied to any single or dual string gas lift well. $$graphic_9B8D549A-F44C-4D78-A6B5-B50FAC46E18A$$