A Comprehensive Review of Sand Retention Test Methods and Data Analysis with a Focus of Application

Abstract

Sand Control completions in long horizontal laterals often present challenging conditions because of a wide range of formation particle sizes and inflow rates which must be contained with a single completion. To aid in the screen selection process, laboratory testing of possible sand control media has proven to be a reliable method to improve the success of the completion. Soft sand completions are generally characterized into two classes of wellbore environments. A rapid wellbore collapse onto the screen or a gradual mechanical failure of the surrounding formation. Depending upon the type of wellbore environment encountered, one sand control test may provide a closer simulation to the failure phenomenon in the wellbore than another. This paper reviews three primary types of sand retention tests that include Constant Drawdown (pre-pack), Constant Rate, and Cyclical Brine. There are several variations on each test method, particularly the constant rate test method. The primary objective of any sand retention test method is to determine the amount and size of solids production through the sand control media with a specific particle size distribution. However, the various test methods provide additional performance data to aid in selecting a sand control system for a given environment. The Constant Drawdown method simulates a wellbore that is in conformance with the sand control media. This method provides retained screen permeability, as well as the formation and system permeabilities at multiple stress levels. Similarly, the Cyclical Brine method simulates a rapid wellbore collapse with an emphasis on injection well shut ins. This test provides system permeability data in both the injection and production flow directions. Lastly, the Constant Rate methods simulate a gradual or erosional failure of the wellbore on the sand control media. In these tests, a fluidized slurry contacts the sand control media in the open annulus, providing increasing pressure data with time. Using the sand retention data from these test methods a master curve is generated, which can predict how the screen will perform with various particle size distributions. A detailed analysis of particle size data down a lateral and interpretation with the Master Curves has been completed and provides a prediction of the performance of the sand retention media across the range of formation particle size distributions. By comparing the various evaluation methods through a reproducible sand retention study, we can optimize laboratory evaluation methods for a variety of wellbore environments. This provides the industry a comprehensive guide for matching wellbore specifications to the ideal laboratory sand retention evaluation method, optimizing the sand control selection to the well.