Production Integrated Sand Control Benchmark for Field Development

Current offshore marginal field development and mature field re-development in Malaysia consistently encountered high development cost and low recovery or incremental recovery. Wells are being drilled and completed at a high cost of 15 to 30 M$ per well while the estimated ultimate recovery (EUR) per well is as low as < 0.4 M Bbl. The associated well development cost (WDC) can be higher than 75 $/Bbl. This high WDC cost can be further aggravated by a significant increase in completion cost if an expensive sand control method is required to mitigate risk of sand production. Rock mechanical properties, stress and pressure distribution can vary widely, from layer to layer, rock facies to facies in the reservoir. Reservoir pore pressure and its distribution could also change drastically during the entire production life cycle. With results of field case studies as examples, this paper is to share our engineering approach in first determining where and when we need sand control based on the geo-mechanical sand-free critical drawdown pressure (CDP) evaluation for the selected well type, configuration and completion. The generated CDP will be later coupled with the current pressure and fluid distribution predicted from the reservoir simulation model and confirmed with the historical pressure and production data for well type, completion and sand control strategy in mature fields. Decision to implement a proper sand control can be made by comparing the CDP with the minimum drawdown pressure (MDP) required to meet the expected production rate target. Sand control method selection shall then be based not only on the sand particle size distribution, well life and the mode of well production (single selective or commingle) but also on maximizing reservoir contact and oil and gas recovery per well. The presented workflows and methodologies is to constitute a new sand control benchmark for well design and production optimization and serve as an engineering guide for optimizing the sand control cost in Malaysia.