LN field is a gas field located in South Sumatra, Indonesia. The conversion trial from medium pressure to low pressure tested at the field in 2009 unfortunately led to sand carried out from formation. Wellhead de-sander and production rate control since then have been initially used as a preliminary effort to reduce the sand production. Due to depleted reservoir pressure and limited availability of formation core, down-hole sand control selection was very challenging. The condition initiated fluid losses during the well service and inability to conduct compatibility testing prior to applying sand control method such as resin coated sand, gravel packing or frac-packed. In addition to well head de-sander as to improve the sand control quality, thru tubing sand screen method has been selected as a unique alternative to face the sanding problem for LN field condition. Rig-less installation and flexibility of sand screen replacement were the main reason why this method was finally selected.
Thru Tubing Sand Screen was installed using regular slick-line unit. The sand screen was installed very close to end of tubing (EOT); it set just around 2 feet above EOT. Special tubing packer was set with a non-explosive setting tool technology with a battery-operated and time-based device.
Since the particle size distribution of sand for sieve analysis was taken from surface sampling, the possibility of sand passing thru the sand screen or sand plugging the screen was still high. But, the thru tubing method provided easy way to install or uninstall the sand screen while wellhead de-sander provided double protection to prevent sand travelling and damaging the surface facilities.
This paper will share on how the down-hole sand control study was conducted, how the sand screen and the wellhead de-sander designed, the installation and optimization process and the success story of the implementation at LN field before it is concluded as an integrated sand control technology,