This case study reports a comprehensive sanding study program for two offshore gas-condensate fields. The results from geomechanics laboratory testing and modeling of sand production were implemented into real-time monitoring of production wells using the Production Data Management System (PDMS). Sand detectors were also instrumented on all production wellheads and integrated into the real-time monitoring. The program will help define the envelopes of optimized production while ensuring safety of production facilities.

Comprehensive geomechanics laboratory testing was conducted on reservoir cores retrieved from exploration and production wells. In addition to unconfined compression tests and TWC tests, the testing included triaxial tests with acoustic velocities during hydrostatic confinement as well as deviatoric axial loading to determine formation rock strength and deformation behaviors. The laboratory results were then used to calibrate strength and elastic properties logs used in sand production modeling. Optimized production envelopes for each well could then be determined. Finally, the modeling results were integrated into PDMS so that downhole gauge pressure and sand detector readings could be monitored and managed real-time for all production wells.

The results revealed that many reservoirs in Hai Thach and Moc Tinh fields have relatively low strength and therefore moderate sanding potential. This study would help define the envelopes of optimized production while ensuring safety of production facilities. These envelopes included sanding prevention criteria in addition to criteria to optimize condensate production and minimize water production. Regarding sand production, downhole gauge pressure are monitored real-time and managed so that drawdowns are below sand production threshold at current reservoir pressures. The key functionality goal is real-time collaboration between onshore and offshore to establish reliable information for reservoir monitoring, improving modeling, and production losses mitigation, which significantly improves production through a proactive well management.

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