Publications

Waterflooding was started in the unconsolidated oil reservoir of the Yakin Central area, offshore Balikpapan, East Kalimantan in 1991. A thick channel sandstone bar type deposits within a small areal size of 28-acre was selected to improve oil recovery. The shallow reservoir depth for the Yakin water injection is at datum level of 2040 ft. The production history showed that primary recovery for this sand would be 30.6 percent due to lack of adequate aquifer support and that a secondary recovely scheme would have to be implemented.A study in 1989 recommended that 3,000 BWPD water could be injected into the existing watered out well on the flank. Three irregular-producers were available to monitor the pilot response.The use of sea water as an injection fluid for the reservoir is one of the successful factors in the pilot project. A single modular water treatment facility comprise several types of filtration and process for oxygen control. Monitoring Program for this project was planned to facilitate the design basis evaluation, as well as to conform the reservoir geology. The project has been proved successful in maintaining water quality for injection life at a minimum cost.Since a constant 3000 BWPD injected water was established in the year 1994, the reservoir has responded favorably to the water injection. Project area pressure increased and response in oil production of more than 80% from the baseline primary recovery was observed.