Subsurface and Surface Optimization Effort to Double Oil Production: A Case Study from Permata Field, Rokan Block

Abstract

Permata Field is a small field that located in Rokan block, Central Sumatra Basin. Permata field discovered and produce since 1977 with current recovery factor 37%. Permata field previously only has 2 - 4 active oil producers with total oil production around 160 BOPD.

To increase oil production in this mature field, several efforts conducted to tackle subsurface and surface issues. Subsurface issues consist of maintaining field reservoir pressure, existing well produce with high water cut, and inactive horizontal well already water out. While surface issue is the produced water that has reached the maximum temperature limit and the water discharge permit limit. Collaborative effort between subsurface team and surface team is needed to resolve the issues and maximize the oil production opportunity from Permata field.

Reservoir management optimization program is launched to address subsurface issues by subsurface team. The optimization program includes natural dump flood review, fluid optimization strategy, and Horizontal well upside potential low quality reservoir assessment. Surface operation teams also launched Permata GS improvement effort to resolved water handling limitation issues. The effort is conducted with pit/cooling pond upgrade and installed additional 3 aerators to reduce water temperature.

The collaborative effort from both teams successfully boosts oil production more than double to average ~400 BOPD.