Production increased fivefold by managing drawdown
Challenge: Manage reservoir drawdown in Statoil's (now Equinor's) Gulfaks Field in wells that are equipped with downhole pressure gauges as well as those that are not so equipped
Solution: In wells with WellWatcher™ permanent monitoring systems, the oil production rate was maximized by maintaining bottomhole flowing pressure slightly above bubblepoint pressure. In wells without downhole permanent gauges, production was optimized using calibration curves based on empirical multiphase equations and pressure data from WellWatcher systems in nearby wells
Results:Statoil (now Equinor) increased production fivefold from 630 to 3,145 bbl/d on a well-by-well basis
Real-time downhole monitoring
The Gulfaks Field development for Statoil (now Equinor) consists primarily of single-phase oil flow without free gas. Some of the offshore platform wells with bottomhole pressure of approximately 28 MPa [4,000 psi] had been equipped with WellWatcher permanent monitoring systems to continuously monitor bottomhole flowing pressure and temperature. The challenge was to adequately manage reservoir drawdown in those wells not equipped with any bottomhole pressure measuring system.
Maintaining bottomhole flowing pressure maximized production
In wells with WellWatcher system gauges, oil production was maximized by adjusting the flow rate to maintain bottomhole flowing pressure slightly above bubblepoint pressure. In wells without downhole permanent gauges, production was optimized using calibration curves based on empirical multiphase equations and pressure data from downhole permanent gauges in nearby wells. Statoil (now Equinor) enhanced production from 100 to 500 m³/d [630 to 3,145 bbl/d] on a well-by-well basis, a fivefold increase.
