Saudi Aramco recently drilled a gas well using Managed Pressure Drilling (MPD) as part of its exploration program. This well was the third exploratory well drilled with the objective to test the hydrocarbon potential of the sandstone reservoirs of Lower Permian era. Since a narrow drilling window between the reservoir gradient and the fracture gradient was expected, Constant Bottom-hole Pressure (CBHP) variant of MPD was planned to be utilized in this well.
There was no Nonproductive Time (NPT) during the MPD phase, hydrocarbon gas from the target formation was measured by the Gas Chromatograph (GC) and properly circulated out via the Automated MPD Control System without the need of conventional well control procedures. Average Rate of Penetration (ROP) increased by three-folds compared to the nearest offset well. Based on the real-time GC analysis, four zones within the target hole section show the most potential for hydrocarbons and further delineations are being planned for these intervals.
This paper summarizes Saudi Aramco's experience gained during the drilling of this well. It further highlights the operational complexity and the challenges faced during the implementation of this technology while drilling the exploratory well with very little offset information.
The paper also elaborates on the lessons learned and how they were implemented continuously with regards to Health, Safety and Environment (HSE) during the MPD operations. It is concluded that the use of an Automated MPD control system integrated with GC in Saudi Aramco's deep gas drilling project represents a technological improvement that will enable the company in achieving its goals in a safer and a more efficient manner.