Evaluating Sand Screen Performance Using Improved Sand Retention Test and Numerical Modelling

Abstract

Sand retention tests have often been used to select optimal screen aperture for standalone sand screen applications. The purpose is to select a sand screen that maximizes hydrocarbon production and minimizes sand production. There are two types of sand retention tests currently used in the industry, i.e., slurry and prepack sand retention tests. The former aims to simulate gradual sand production condition with an open annulus between the sandface and the screen, and the latter to simulate the condition where no such annulus exists. There are, however, no agreed industry standards on how sand retention tests should be performed and test results interpreted. This paper presents a combined experimental and numerical modelling study on sand screen performance. The objective is to develop an improved methodology for optimal sand screen aperture selection by addressing some of the limitations presented in the existing sand retention tests. A new sand retention test facility has been developed at CSIRO, incorporating a number of improvements into the design and experimental procedure. A key component of the improvements is the ability to separately measure retained screen permeability and sand pack permeability. Correlations have been developed between sand screen performance and key parameters of the sands and screen based on a large number of sand slurry retention tests. Furthermore, the sand retention process was simulated numerically using a 3D fully coupled Discrete Element (DEM) – Computational Fluid Dynamics (CFD) model. Parametric studies have been conducted to assess screen performance and to gain a better understanding of sand retention and production mechanisms.

A review of experimental studies on sand screen selection for unconsolidated sandstone reservoirs

“…One of the key parameters for SAS is the sand retaining precision, which determines the success of sand control and whether high production rates can be achieved. The objective of SAS selection is to identify screens that effectively retain sands while maximizing hydrocarbon production, by choosing optimal sand screen aperture and evaluating the limitations during sand retention tests (Wu et al 2016;Changyin et al 2016).…”

“…Screen performance is often evaluated based on the following two factors (Wu et al 2016;Mondal et al 2011;Ballard et al 2016): Table 3 Lists of empirical selection criterion for sand control aperture (Wu et al 2016) W-slot width, d5-particle size at 5% cumulative weight distribution, d10-particle size at 10% cumulative weight distribution, d50-average particle diameter of the sample, Uc-uniformity coefficient…”

“…• Mass of sand produced as a function of time or mass of sand injected which gives some measure of a screen's sand retention efficiency • The pressure developed across the screen and the sand pack to give some measure of screen's plugging tendency • The particle size distribution (PSD) of the produced solids, which will help assess erosion capability. Wu et al (2016) reported that in the sand retention test, the sand has to be deposited onto the screen at a constant drawdown pressure, and not at a constant flow rate. This is to avoid misinterpretation of the rapid increase in the pressure profile attributed to screen plugging from a constant flow rate test.…”

“…This test measures the weight of sand produced as well as the pressure drop that occurred during the test. Figure 4b shows the experimental setup for the sand-pack test (Agunloye and Utunedi 2014;Wu et al 2016;Mondal et al 2011;Chanpura et al 2011).…”

“…The aim of conducting numerical simulations for screen size selection is to avoid repeating laboratory tests in areas where extensive sand retention test data are available. Currently, numerical modeling does not accurately account for interactions between fluids and the particles (Agunloye and Utunedi 2014;Wu et al 2016;Feng et al 2012;Mondal et al 2010;Markested et al 1996;Constien and Skidmore 2006).…”