Integrated Production Optimization Leads Significant Gain from North Kuwait Jurassic Gas Challenging Deep Tight Carbonate Fields

Abstract

This paper demonstrates the production optimization methodology being used by Kuwait Oil Company Jurassic gas that added significant contribution of approximately 37% of total field incremental production gain in 2021. Production optimization is a continuous iterative process to improve production, especially in mature fields. The North Kuwait Jurassic Gas field’s team has adopted an integrated enhanced and structured process to identify opportunities for production optimization with a pro-active approach focusing on flowing wells and rig-less interventions to tackle production challenges and achieve production targets. The Jurassic gas asset has unique mature-field challenges. It produces mainly from deep (up to 19,000 ft MD) high pressure and temperature, conventional and unconventional tight carbonate reservoirs, highly deviated to horizontal wells, different completion configurations (4.5in monobore, 3.5in × 5in liner, and 4.5in Multi-stages completions), wellbore cleaning and accessibility, scaling and flow assurance, high heterogeneity and permeability contrast among different flow units and dual permeability effect (matrix and natural fractures), production decline due to pressure depletion, liquid loading, high H2S (up to 13 mol%), surface production facilities limitations (e.g. limited MP and H2S handling capacity). effectiveness of subsequent stimulation treatments of such complex heterogeneous reservoir to improve well productivity and connect the natural fractures. The recovery from such complex heterogeneous reservoirs is extremely challenging if conventional development strategies are applied and need for appropriate production optimization methodology outlined here. The Heterogeneity Index process is utilized to rapidly demonstrate production gain opportunities via quick screening method of identifying preliminary candidate wells with anomalous behavior (over/under performance) for further analysis. The results from this screening tool were utilized to identify the families of type productivity problems at field and well levels with solution categories for production enhancement. Representative wells were selected for detailed diagnostics based on the relevance and size of productivity impact and the potential of its well deliverability. Once a few "top potential" wells were identified, production engineering workflows were implemented to assess and forecast the potential of production increase and to determine and evaluate the best solution design and intervention action. Detailed production optimization process provided recommendations of various remedial intervention solutions to improve well production potential via productivity enhancement ranging from complex matrix and fracturing stimulation, additional and/or re-perforations, wellbore cleaning, flow assurance solutions, to choke management. Other advanced technologies were applied to improve various strategies, including completions, perforation, stimulation, and production control. The executions of recommended interventions added significant contribution of approximately 37% of total field incremental production gain in 2021. Such production optimization process, experience and lessons learned will be shared where it can be used in analog fields.