ENVIRONMENTAL MANAGEMENT OF SAND PRODUCTION FROM OIL WELL

Abstract

Sand production remains a persistent challenge in unconsolidated petroleum reservoirs, with significant operational and environmental consequences. This study investigates the environmental management of sand production in Niger Delta oil wells by integrating geomechanical analysis, analytical modelling, and multivariate statistical prediction techniques. A structured workflow combining reservoir characterization, production data analysis, and discriminant function modelling was employed to evaluate formation stability across selected wells within the 8550–8650 ftss interval. Results reveal pronounced heterogeneity in formation integrity, with discriminant factor (F) values ranging from −3.665 to 1.994, indicating coexistence of both stable and highly unstable wells within a narrow depth window. Reservoir pressure depletion emerged as the dominant control on sand production, significantly increasing effective stress and formation failure risk. A strong inverse relationship between water cut (BSW) and formation stability was also established, confirming its critical role in accelerating sand generation. Although flow rate, productivity index, and gas–liquid ratio influence sand behaviour, their effects are secondary to pressure and water production dynamics. The developed discriminant model effectively classified wells into sanding and non-sanding categories, demonstrating strong predictive capability for formation instability. The study further highlights that uncontrolled sand production poses substantial environmental risks, including infrastructure damage and contamination from produced solids. Consequently, integrated reservoir management, real-time monitoring, and proactive sand control strategies are essential for sustainable field development