Publications

A number of water shut-off jobs had been implemented in Walio mature oil field in Salawati basin, Papua as efforts to reduce water production while gaining oil and importantly to minimize the operating cost for water treatment. The excessive withdrawal rates beyond the well critical rate due to implementation of Electrical Submersible Pump (ESP) as artificial lift in the early field life could have activated the water coning that was observed by abrupt increase of water production in the field. The field consists of stacked carbonate reservoirs with large permeability contrast that could be responsible for multi-layer water channeling. In order to apply the desirable water production controlling technique (either mechanical or chemical water shut-off), a screening method was applied in the field whereupon the execution is prioritized on wells that could give economical oil gain while reducing water production. After implementing the method of Simulation Opportunity Index (SOI) within the history matching result of the dynamic model, the recent Hydrocarbon Pore Volume (HCPV) generated from the dynamic model is mapped to see the water-flooded wells that still holding potential. Additional production diagnosing techniques such as Chan plot are performed to investigate the water production problem in the wells. Several candidates were selected whereas the mechanical water shut-off dominates the treatment due to inexpensive cost and easy operation. Several achievements are notified that the water-cut in a lot of wells are manageably reduced after the treatment for a period of time with oil gain. The integrated approach between reservoir and wells production has generated a streamlined method to seek the potential wells for water shut-off treatment. The understanding of specific water production problem in the wells is also critical to increase the success ratio of the treatment.