Abstract
This paper presents the lessons learned from optimising the sand control and management strategies of an oil field (Field E) after multiple sanding events and well failures. It presents how the old sand control solution was selected, the failure root causes, and the remediation options considered. The new sand control method, and the performance of two re-drilled wells after two years of production are also presented.
Field E is a sandstone field with oil and gas-cap gas at initial conditions, and was initially developed with 5 production wells, 2 water injection wells, and 2 gas injection wells. The development wells were drilled from an offshore platform, and completed with stand-alone screens (SAS) in 2013. Oil production commenced in late 2013, and within three years, sand production was observed, and 4 of the 5 oil production wells had failed. The 4 wells were re-drilled in 2017, and the sand control strategy was changed from stand-alone screens to frac-packs.
Key lessons learned include completing sand strength studies pre-development, avoiding off-the-shelf sand control solutions, and completing sand control design studies based on service contractor capability, fines control, oil production rates, and sand control as key selection factors. Nearby wells should be shut in during infill drilling operations to avoid short circuits, drilling mud losses, completions damage, and well integrity failures.
It is recommended that the bean up procedures of wells with sanding events are changed to slow bean up to preserve well integrity, oil production, and cash revenues. The asset team should consider installing sliding sleeves or inflow control devices for zonal testing and to choke or close sand production zones if needed. The asset team should also consider installing a test pipeline and a test separator to allocate sand production volumes from each well, clean up new wells, sample the wells for water salinity measurements, and other benefits.
