Partial Processing: Produced Water Debottlenecking Unlocks Production on Offshore Thailand MOPU Platform

Abstract

Abstract An operator in the western Gulf of Thailand installed two water management Partial Processing systems on their D and E Mobile Offshore Production Unit (MOPU) platforms to increase oil production. Electric submergible pump (ESP) wells connect to each MOPU for primary gas-liquid separation. The produced liquids, at ~90% water cut, are piped to a dedicated Floating Storage and Offloading (FSO) tanker for water separation and oil storage. The separated water is pumped back to the MOPU for re-injection disposal. High volumes of produced water created bottlenecks at the MOPU separator and the MOPU-FSO transfer lines (both directions), which then limited oil production. Additionally, substantial energy is spent on fluid heating to prevent wax formation in the flow lines to the FSO. Much of this heat is lost to the bulk water phase. In 2016, a Partial Processing system was retrofit on each MOPU process facility for bulk removal and treatment of produced water. Water removed at the production manifold is treated and transferred directly to the injection system, thus bypassing the primary separation, transfer piping, fluid heating, and FSO storage facilities. Water debottlenecking increases oil production by 80% and reduces the in-field transfer volume by 62%. This Partial Processing project is a step-change in field economics, allowing a three-month payback. Field layout, water cut issues, and the Partial Processing solution are detailed. Partial Processing has increased revenue and reduced operating costs at the facility.