The Middle East has long been a pioneer in innovation in drilling and completion technologies for multilateral wells. It was here that the first1 multilateral tool (MLT) on coiled tubing was used to access and stimulate each openhole lateral in a trilateral well. Over the years, several2-4 applications of this and similar technologies have been made. In each instance, a conventional upper completion system was installed.
In a multilateral well with a conventional upper completion and an openhole lower completion, there is no independent flow control from each lateral. Because of this, production is not optimized to account for differences in the production rate or reservoir quality of each lateral. For a well with an upper intelligent completion system (ICS), independent control of flow from each lateral is possible through the use of surface controlled flow control valves (FCVs). This feature addresses the shortcomings of the conventional upper completion mentioned earlier.
The challenge in performing an acid stimulation of each openhole lateral in a well with an ICS is the inability to access any of the laterals after the ICS has been installed. Current technologies do not afford this option and designs in the pipeline do not have field proven applications.
This paper chronicles a novel attempt at acid stimulating each openhole lateral of a trilateral well in a carbonate reservoir. It includes the installation of the ICS in the same well. The challenges, results, learnings and future courses of action are documented in what should provide a template for continuous improvement.