Smart Well Completion Optimization in Multilateral Wells

Abstract

The ability of smart well completions (SWCs) to best function as intended in the field, has led to renewed focus on smart well completion optimization opportunities. The action of inflow control valves (ICVs) is key to improved management of flux imbalance and premature production delay of unwanted fluids from contributing laterals of the intelligent wells. Difficulty with the use of ICVs includes the complexity to determine all possible combinations of valve settings (given 11 possible positions per valve on each lateral). Imposing specific wellbore pressure profiles in dual or trilateral well completions, to control production, or achieve pressure responses within ideal electrical submersible pump (ESP) operational ranges for continuous uninterrupted functioning of the smart wells is even more challenging. Real-time data acquired during SWC tests at various combinations of valve positions was modelled to determine contributions from motherbores and/or laterals in 11 smart wells. The ICV positions and surface chokes were controlled, while flow rate, wellhead pressure/temperature, and intake pressure/temperature were measured. From the tests, the optimal settings for individual or commingled flow were determined in real time from the network models (objective functions include minimizing water, maximizing oil, subject to staying within effective ESP intake pressures). Tests showed wells with up to 34% and 57% basic sediment and water (BS&W) from the motherbore and lateral respectively and corresponding normalized rates of 1.539/1.138. Implementing results of the model resulted in a normalized oil gain of 3.800 and 27% BS&W reduction from both laterals. The model yielded the optimization parameters, which resulted in choking back drainage points to achieve the water cut reduction and realize the oil gain. Test data revealed an accuracy of more than 90% match between calculated and measured flow rates of targeted drainage points. The results confirm that modeling ICV completions to determine optimum valve positions and rate targets is possible for an entire SWC or specific laterals.