Introducing Integrated Surface & Subsurface Sand Management Systems for Rigless Interventions in East Malaysia

Abstract

One of the main challenges in the well intervention in offshore brown fields prone to sand production is both subsurface sand handling and also surface sand handling during the flow back and well cleaning. The field of interest is located offshore in East Malaysia. The field had been producing for almost three decades and is prone to sand production with no capabilities of surface sand handling. This paper describes the integrated solution to address sand production on both surface and subsurface, targeting sand production from the unconsolidated reservoirs but also from well clean up before and after well intervention. In order to provide a cost effective solution for the new potential layer below the existing gravel pack zone, through tubing gravel pack technique was chosen as the sand control technique. This enabled the new zone to be produced in the optimum draw down without the risk of having sand production at surface. However prior to that, the rathole for the potential new layer had to be cleaned up using coil tubing. The sand and debris from this cleanout had to be circulated out to surface and needed to be separated before being disposed properly onshore. A cyclonic desander was temporarily installed on surface to achieve this. As a result, the integrated system provided overall solutions where downhole sand control was achieved and the cleanout fluid was free from solids to ensure no cascaded damages to the existing process facilities.The system permitted to execute two wells cleanups, one through tubing gravel pack while complying with the very strict sand content limitations -particle size less than 45 microns and not more than 15pptb. The newly introduced technologies proved to be fit-for-purpose and robust, complying with sand content limitation as well as with all the other constrains.The General description in term of operations and installation of such system as well as lessons learned and recommendations have been outlined in the paper that can be used as a reference for similar applications in the near future.