2018 年 83 巻 6 号 p. 434-441
Lower Miocene sandstone reservoir in Rand Dong Field, within Block 15-2 offshore Vietnam, has continuous oil production since 1998. Since oil production had steadily declined from 2002 despites additional developments, full field scale application of hydrocarbon gas enhanced oil recovery （HCG-EOR） started to be investigated from 2008 to maximize oil recovery. After the executions of feasibility studies, pilot test and installations of facilities, the project of HCG-EOR full field scale started in October 2014.
During three years of implementation, the project has been achieving the planned enhanced oil recovery while adjusting the scheme of water alternating gas （WAG） injection. Even though some operational tasks arise such as sand production, countermeasures are investigated and being applied as the appropriate way. For the optimization of WAG injection, the areal monitoring and application of WAG injection pattern have been conducted. Furthermore, the effect of HCG-EOR is divided into the primary, secondary and tertiary effects and quantified respectively for the further optimization plan.
This paper presents the outline of the project before HCG-EOR full field scale application, and the ?ndings through the actual operation of HCG-EOR full field scale including results and evaluations for the further oil recovery.