This paper describes one of the first worldwide pilot implementations of a new generation of downhole digital gas lift system. This system brings a step change in the way gas lifted fields are completed and operated. In a joint effort between operator PTTEP and service company Silverwell, this digital intelligent system was successfully installed in one development well which deviated and depth around 7500 ft in the Sirikit onshore oilfield of Thailand. Well completion and commissioning were done in January 2017.
The digital and intelligent artificial lift technology is an in-well gas lift system that overcomes the well design and operational limitations of existing side-pocket mandrels and valves. This system enables the operator to optimize gas injection rate, and change the depth of injection to satisfy well conditions, and without any intervention required. Each in-well unit features up to six different sized orifice valves to accommodate a wide range of unloading and production conditions, as well as in-built pressure and temperature sensing capability. As reservoir conditions change the injection orifice can be remotely adjusted from surface and confirmed in real-time. Multiple in-well units can be connected by a single ¼" TEC cable.
With regards to reservoir properties from logs and performance of near-by wells, PTTEP was expecting a fast decline in reservoir pressure. Therefore, the flexibility and real time optimization of the Silverwell system allowed them to monitor closely the changing reservoir conditions and adapt gas lift accordingly. The benefits observed in terms of reductions of interventions, production optimization and gas savings will be described in this paper.
One of the first worldwide pilot implementations of a new generation of downhole digital gas lift system, with results and benefits detailed in this paper.