Mitigating Sand Production by Polymer Injection in Indonesian Offshore Field

Abstract

Several fields in South East Asia are suffering from excessive sand production due to clayey unstable reservoir rock. Sand production induces undesirable phenomena such as production loss due to sand accumulation in the well, damage of the pump and of the surface equipment, frequent well shut-in and heavy costs for cleanout jobs and pump changes. The operators are looking for an easy and cost-effective technique that could be deployed in the field, if possible rigless. In a previous paper5, a pilot treatment consisting of specific water-soluble polymer injection showed good results in terms of sand production reduction and preservation of well performances. The polymer adsorbs strongly on the reservoir rock, forming a continuous film on pore walls. The film has a consistency of thin sticky gel stabilizing the rock. Moreover, the polymeric film acts as Relative Permeability Modifiers (RPM) and thus maintain oil permeability while reducing water permeability. This RPM property enables the deployment by bullhead injection into the whole open interval. Field extension has been scheduled and similar treatments have been performed in 4 new wells. In the field, the polymer is injected by coiled tubing in each open interval selectively. The polymer is pushed in the formation by diesel/water postflush, which also re-saturates with oil the near-wellbore area and help production re-start. The feedback obtained so far can be listed as follows: No production loss occurred in all the treated wells.Sand-free production rate could be increased after the polymer treatmentSand production was totally stopped for a few months before coming back again after 4-12 months, at much lower rate than before.A re-treatment induced new period of sand-free production for several months. Such results confirm the sustainability of the polymer technology. The field methodology has been optimized. It opens new perspectives and could become a new sand control system in the toolbox of the profession.

Chemical sand production control: a review of materials, methods and characterization

“…Compared to conventional dense resins, the pores of the porous polyurethane provide seepage channels that limit permeability reduction . Many field applications have shown that resin injection for sand production control can effectively improve reservoir mechanical properties and reduce sand production (El-monier et al, 2013;Shang et al, 2019;Izurieta et al, 2020;Mahardhini et al, 2021;Zaitoun et al, 2022;Miri et al, 2023;Peerakham et al, 2023;Stephen Babagbemi et al, 2023).…”