Reviving Productivity in Mature Oil Fields: Coiled Tubing Hybrid Fiber Optics Technology Leading the Way to Operational Efficiency and Remarkable Production Rejuvenation Following an 8-Year Well Inactivity - A North Kuwait Vanguard
Authors: Slama Mohamed Hedi , Badrawy Kareem , Ayyad Hazim , Sunagatov Rustem , Ajmi Abdulaziz Nayef Al , Hajji Ahmad Al , Sebaih Mohannad Adel , Alsubaie Abdulaziz , Fajardo Sergio Rondon , Rajagopalan Vijay Shankar , Ahmed Abdul-Samad Mohammed , Tapdiya Raghuveer Balaprasad , Kar Hassan Saber Hasan , Hassan Abdulaziz Ahmed 
Published: November 2024

This paper explores groundbreaking methods for economically enhancing production in a mature oil field in North Kuwait asset through the strategic use of Coiled Tubing Hybrid Fiber Optics Technology (CT HFOT). Developed in response to well suspension challenges in the Northern field, a complete revamped intervention protocol was to refine the field development strategy and optimize Rig-based interventions.

Initiating a comprehensive campaign, the reservoir management team aimed to clean, perforate, and stimulate long-term suspended wells. The optimization journey involved a meticulous process, integrating e-Line-enabled coiled tubing interventions, and conventional coiled tubing setups. Recognizing the potential for further refinement, the campaign leveraged CT HFOT, eliminating the need for a second CT reel. This innovative protocol resulted in a reduced number of runs, and substantial cost savings. The advanced methodology allows for clean-out, perforation, and stimulation, with a single coiled-tubing rig setup. The technology integrates optical fibers and conductor cables with insulation, overcoming prior CT system dependencies on downhole batteries, especially in extended rig operations.

Addressing an old well drilled in 2015, initially designed as a Mauddud producer with a 4 ½ inflow control devices (ICD) horizontal lower completion, this well faced suspension due to non-production. A final attempt involved deploying CT HFOT for the first time in Kuwait, utilizing addressable switches and reducing anticipated 5 CT runs to only 3. The subsequent matrix acid stimulation with a single-phase retarded inorganic acid system (SPRIAS) displayed superior wormholing performance compared to conventional emulsified acid treatments. Introducing CT HFOT significantly reduced Workover Rig operational time by 68 hours, optimizing rig-up time between CT runs and delivering substantial cost savings to the operator. Employing a single CT reel minimized safety risks associated with personnel exposure to heavy lifting equipment and addressed concerns related to battery handling and management.

The presented method delivers substantial time and cost savings. Supported by this first field trial case, the multi-disciplinary team effectively targeted suitable zones for perforation and stimulation using the state-of-the-art CT HFOT technology and the SPRIAS acid system. The paper includes technical and economic comparisons with conventional practices, emphasizing the potential applicability of this methodology to other fields. Compliance with stringent safety criteria is highlighted. This study thoroughly illustrates job design, pre-treatment preparation, operational details, and post-job result analysis, with a dedicated focus on HFOT alongside a detailed comparison with conventional operations. The most notable achievement is the successful revival of a well dormant for eight years, showcasing the transformative impact of CT HFOT intervention workflow in rejuvenating stagnant assets. The well, after being dormant for such a prolonged period, exhibited a remarkable 400-fold increase in production, underlining the technology's prowess protocol in revitalizing mature wells.