Evaluation of the P.I. in Non Flowing Wells -Case History
By
Mohamed Samir1, Samir Siso1, Mostafa Safwat1
(1) Faculty of Engineering, Cairo, Egypt
One of the most important problems facing reservoir management and additional development in depleted fields multi layered reservoirs is the definition of the Productivity Index for non-flowing wells.
Permeability data, from core analysis and initial tests correlated with petrophysical characteristics of the rock from open hole logs are widely used in numerical simulation models of the reservoir dynamics. This approach, basically followed to evaluate well productivity, doesn’t take into account the mechanical damage of the formation through the different phases of drilling, completion and workover.
In this paper the results of different methods (open hole logs, production test, PLT using Y-tool, back calculations of the ESP pumps, fill up tests...) are summarised and compared to evaluate the actual PI of all the wells producing from the reservoir of Kareem Rudeis in Belayim Marine field (70 wells with a daily rate of 85000 bopd).
Wells were categorised based on their completion factors ( P.I. actual over P.I. by correlation) and work-over activities schedule has been planned in order to optimise the production and injection rates (accurate pump design, reperforations, vacuum, back surging...).