Paper Number: OTC-30327-MS

https://doi.org/10.4043/30327-MS

Abstract:

The production in oilfield "A" in South China Sea is reducing dramatically, with known fine-grain migration into the near-wellbore area. The heavy oil unconsolidated sandstone is water drive reservoir. It featured high content of clay (>10%). Gravel packing and screen are used to prevent the sand production. Oil recovery is low due to the water breakthrough (WBT) in this field.

Continuous Pack-off Inflow Control Devices (CPI) is a proprietary water control technique including two operational steps: first run ICD strings, and then inject special designed proppants into the wellbore annulus. The results show this technique is cost-effective, and reliable oil recovery method.

This paper presents a method of using ICD and CPI particles to maximize oil recovery in sandstones. Compared with other water control methods, the CPI advanced them by delaying/reducing water invasion. The case study shows the production is stable in 12 months without sanding issue. Wells with ICD and swellable packers often lost production because of the accumulation of the fine-grain and plugging around the screens. The well with gravel packing reached water cut of 70% at a cumulative oil of 6000m₃ while the well with CPI technique showed water cut of 10 % when 6000m₃ oil was produced.