Completion Standardization Utilizing Conformable Sand Screen Technology in Multilayered Ultrafine Sand Reservoir

Abstract

The development activities of CABGOC Block 0 pose various challenges to completion design. Multiple types of reservoirs are encountered, while it is also critical ensuring field development remains economic. Completion standardization has been an important tool to maximize operational efficiency and reduce costs of installation. Nonetheless, given the variety of reservoir types found in the area of operation, few completion types are required to solve most of the cases. Despite of having successfully implemented completion standards in several types of reservoirs, there was a gap on the type of completion to efficiently drain multilayered fine particle reservoirs with sanding tendencies. These field characteristics make standard completion techniques difficult to deploy, therefore a novel conformable sand screen solution was selected for a field trial. This paper describes the plan, preparation, execution, and the results of the conformable sand screen deployment in CABGOC's N'Singa field. Furthermore, it demonstrates how effective the conformable sand control technology can be established for a multi zone open hole type of reservoir. Integral zonal isolation and flow control of various zones provided flexibility in production management for a four well campaign. The Shape Memory Polymer (SMP) conformable sand screen technology was key to produce sand free from the fine particle sands in this marginal field in Cabinda Province offshore Angola. Unlike the conventional sand control technique, the conformable sand management system selected for this field trial leverages a unique SMP material that expands downhole in the presence of an activation fluid and conforms to the borehole wall. Compatibility and expansion tests were conducted in the planning stage to validate screen conformance with selected completion fluids. Tests were also used to define deployment procedures and optimal fluids management practices for the completion operation. Installation was successful on all four wells as per plan. All equipment and fluids were managed and operated efficiently with flawless execution. The wells were brought to production and the results confirmed the effectiveness of the technology in terms of sand retention, and completion efficiency during production. The project was concluded with significant reduction in rig time, personnel requirement, fluid management, and pumping operations. This allowed for selective production of reservoir that would not have been possible with standard techniques. Additionally, the obtained results facilitated the decision to implement conformable sand screens as standard completion design for other fields in the reservoir with similar challenges as those observed in N'Singa.