Breaking the Limit: Breakthrough Technology to Develop Ultra Shallow Heavy Oil with Oil Mining

Abstract

Shallow heavy oil in Indonesia is one of undeveloped resources with high potential that require breakthrough in unconventional production technology. Iliran High Field, located in South Sumatera, has this potential and been conducting several production method for optimum production since 2011. The depth of the potential formation is 10 – 500 ft with range of viscosity 200 – 600 cp at reservoir temperature. Production methods including steam injection, radial jetting, chemical injection and variety in borehole size have resulted in low production rate. Major technical challenge is the reservoir have naturally very low reservoir pressure thus limiting possibility for further stimulation. Finding the production solution for this field would require technology that is not limited by pressure, which ultimately leads Medco to explore the opportunity of oil mining. Oil mining has been done for producing the shallow depth oil sand and has proven effective with high recovery factor. Since this is novel in Indonesia, preliminary studies were conducted. The studies conducted in laboratory use conventional core with the objective of selecting optimum extraction method and parameters. High recovery factor of > 94% was achieved by means of selecting solvent extraction method and parameters such as solvent type, ore to solvent ratio and ore size. The high recovery factor result concluded that oil-mining method is highly feasible and interesting for development. For the next step of this journey, larger scale of study is planned which includes real excavation result and further study of economic analysis. The positive result could be the solution for optimally produce the shallow heavy oil potential.