Optimization of Sand Control for Unconsolidated, Shallow, and Low-Pressure Sandstone Reservoirs: A Suriname Case Study

Abstract

Abstract Oil and gas production from unconsolidated sand reservoirs generally requires a production sand screen and usually a gravel pack in the well bore for optimum sand control. Existing criteria such as Tiffin, Saucier and Coberly have provided guidelines for conventional gap based filtration technology. However they do not apply very well to some newer technologies of today. Some of these newer technologies include Premium (2D) screens, with fusion-bonded laminates, or MeshRite (3D) screens with angular compressed metal fibers as Stand Alone Screen (SAS) completions. These screens may use multiple layers of wire mesh and a complex shaped pore opening, which result in retention performance quite different from conventional gap-based systems. Therefore with SAS completions, compatibility with the formation sand size is critical in providing optimum performance. Consequently it might be desirable to adjust existing criteria for specific types of reservoirs, in this case unconsolidated sandstone reservoirs. A combination of SAS lab data with SAS field performance will show that existing criteria need to be adjusted specifically for unconsolidated sandstone reservoirs. A Staatsolie case study in Suriname will be presented to demonstrate the performance of these newer technology screens for specifically unconsolidated shallow-reservoirs. Staatsolie produces heavy oil from shallow, low-pressure, unconsolidated sandstone reservoirs. Wells are mainly completed as vertical open hole gravelpack with production based on progressive cavity pumps. Additional completion methods include cased hole/openhole gravelpacked and or screenless (SAS). In the SAS pilot, 28 wells were completed with Premium or MeshRite screens. Of these, only in 6 wells fine formation sand production was measured. Based on available Particle Size Distribution (PSD) data of 9 wells, a comparison is made between field and lab screen performance. These results will be matched up to Tiffin's criteria [8]. Based on summaries of these screen performance, guidelines for screen type selection for various completion scenarios will be developed for unconsolidated low-pressure shallow reservoirs. Completion types to be covered in the analysis will be open and cased SAS, as the primary focus with respect to 2D and 3D screens applications.