Publications

Many Indonesian oil fields are now in a mature stage of production with declining primary production, however about 62% of the oil in Indonesia is still lagging in reservoirs after primary and secondary drain. (LEMIGAS, 2011). Oil production has declined steadily with a decreasing rate of approximately 12% per year (Annual Report, BPMIGAS, 2011) while tertiary recovery techniques have rarely been used. Currently, the EOR contribution to the national oil production is about 20%. The potency of Indonesia EOR is predicted to be around 42.8 million barrels of oil and around 58% of this number is accumulated in the Central and South Sumatera region. Therefore, remaining reserves are 49.5 billion barrels and the EOR potential is approximately 3.3 billion barrels. (Muslim, 2013). Base on the analysis above, there is an opportunity to implement a new EOR method to increase the oil production, such as surfactant. However, the selected chemical must be able to lower the oil viscosity, lower IFT and alter the oil wettability. This paper presents an overview of two successful EOR field experiences by using chemical on carbonate and sandstone reservoirs in Indonesia in Bentayan field and Sungai Lilin oil field. The details of these publications have been published previously. The first section of this paper includes a brief description of chemical injection in the Bentayan field and the second section includes a review of EOR chemical flooding implemented in the Sungai Lilin field, both located in the South Sumatra basin. The incremental increase in oil production showed in huff n puff wells and several of the surrounding production wells, with the highest increase in oil production coming to about 400% at peak oil production. In this case, a special chemical treatment, SEMAR (Solution by Chemical Modifier to Enhance Recovery) had been implemented in this field using huff n puff technique. We will also discuss the evaluation of the pilot field application and the relationship between laboratory results and field scale performance.