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ABSTRAK Ariel Delano Massie
PUBLIC Suharsiyah

2021 TA PP ARIEL DELANO MASSIE 1.pdf?
Terbatas  Suharsiyah
» Gedung UPT Perpustakaan

The inability of primary and secondary recovery methods in fully extracting recoverable oil from the existing fields and the lack of new major reserve discoveries have been the two main issues in the oil and gas industry worldwide these days. The best solution to solve both problems is by performing Enhance Oil Recovery (EOR). One of the EOR methods that have become the center of attention for many researchers in the past few decades is Low Salinity Water Injection (LSWI). This emerging EOR method could give a significant increase in oil recovery compared to conventional waterflooding. Recent studies on LSWI have found that it can be combined with another EOR method to get even better results. One of the promising combinations is LSWI and Water Alternating Gas (WAG) Injection, which is called Low Salinity Water Alternating Gas (LSWAG) Injection. In the LSWAG Injection, the type of injection gas that is preferred to be used is hydrocarbon gas. Compared to other gases, hydrocarbon gas is easy to obtain, resistant to operational problems like corrosion, and good for the environment when is injected back to the reservoir. This study is conducted to design the low salinity water alternating hydrocarbon gas injection at "B" Structure in "S" Field, Indonesia. The “B†Structure is identified as a sandstone reservoir with mix-wet wettability which makes it suitable for LSWAG Injection. In addition, hydrocarbon gases produced from the reservoir can be utilized as injection gas. Based on the MMP value that has been calculated, the gas flooding part in this LSWAG Injection is indicated to be immiscible. Injected water salinity, water injection rate, and gas injection rate are the parameters that become the focus of this study. Reservoir simulation and sensitivity study using a compositional simulator, CMG GEMTM, were performed to study the impact of those parameters on oil recovery and the optimum values of the parameters. The results of this study conclude that the optimum design for LSWAG Injection in this reservoir is by using 1,800 ppm of injected water salinity, 1,500 BWPD of water injection rate, and 1 MMSCFD of gas injection rate. This optimum case could deliver 7.81% incremental of oil recovery factor or additional 0.56 million barrels of oil cumulative compared to the base case. Therefore, low salinity water alternating hydrocarbon gas injection is highly suggested to be implemented in this reservoir.