Tendeka has successfully installed an optical reservoir monitoring system in an offshore platform well for a major operator in West Africa. The 900m horizontal openhole is completed using 6 5/8” sand screens with external swell packers for zonal isolation of the 3 reservoir sections.
The upper completion conveys the monitoring system on a 2 3/8” stinger inside the sand screens. The stinger is suspended from an ESP system and a high set production packer. DTS provides monitoring across the whole reservoir section whilst each of the 3 zones has a single point pressure gauge. A 4th pressure gauge is located above the reservoir to provide co-mingled P&T data.
The monitoring solution consisted of Tendeka’s Sentinel distributed temperature sensing (DTS) system along with four SmartCell optical pressure and temperature gauges. Combined with DTS, the gauges provide a complete real-time pressure and temperature profile of the reservoir enabling the operator to optimise well performance. The pressure gauges enable more accurate interpretation of the inflow profile and analysis of phase contributions along the horizontal interval. Data is continuously available in real-time providing unprecedented understanding of flow contribution and immediate detection of water breakthrough.
Tendeka’s industry leading DTS systems can measure temperatures to a resolution of 0.01?C at every metre along a fibre optic cable up to 30km long. The SmartCell optical P/T gauge technology allows multiple gauges to be deployed on a single string, providing a cost effective solution to monitoring many more zones of a well. Optical technology eliminates downhole electronics, providing greater reliability, particularly at higher temperatures compared with conventional gauges.
A number of downhole fibre splice assemblies were installed with no degrading effects on the measurement performance of both the DTS and FO P/T systems. The safe and successful installation is testament to Tendeka's field engineering and project management expertise.
