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Sand Control Study and Assessing Suitability of Installing Expandable Sand Screens (ESS) in Comparison with IGP in Cased and Open Hole Wells in Mansou
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 4th EAGE St.Petersburg International Conference and Exhibition on Geosciences - New Discoveries through Integration of Geosciences, May 2010, cp-156-00125
- ISBN: 978-90-73781-79-5
Abstract
Wells are completed with cased-hole largely due to the requirement to achieve isolation, either at the time of completion or later in producing life. The compromise to productivity is offset by the ability to control water production isolate shale sections, or produce zones selectively. Expandable reservoir completions offer the ability to achieve the required isolation with open-hole productivity. It is reported that approximately 70% of the world oil and gas reserves are found in unconsolidated formations. Sand production is a phenomenon associated with drag forces induced by fluid flow through unconsolidated porous media. Consequently, there is a global interest in research and development for understanding the mechanisms, associated enhanced oil recovery, and sanding control. There are some unconsolidated reservoirs in Iran and sand production is a major dilemma facing operating oil and gas companies over years. The difficulty of determining whether or not sand control is required in a given well is compounded when the well is drilled in an area where there is little or no producing experience and where the various reservoir factors are slightly different from previously exploited regions. Even if the reservoir and formation properties are almost identical to other developments, the operating conditions and risks may be such that different strategies apply. Among the methods for preventing sand production, ESS Screens have already been successfully deployed for NISOC in both Ahwaz and Mansouri fields, with five systems installed in vertical cased hole wells between June 2003 and April 2004. All systems were successfully installed without incident, with well productivity in all cases far exceeding that previously achieved using internal gravel packs. More importantly, long term well performance has not deteriorated, with sand-free production being maintained at constant wellhead pressure, confirming ability of ESS Screens to provide long term sand retention integrity and substantial sustainable productivity gains compared to conventional gravel pack solutions. To fulfill the objectives established for this study, certain reservoir, well and production data gathered to assess efficiency of ESS compared to gravel packings.