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Terbatas Suharsiyah

Based on the factors related with Microbial Enhanced Oil Recovery (MEOR), microbial growth is one of the most critical factor that determines the population of microbes, their metabolism and metabolic by-products which may lead to physical alteration in the reservoir, increase oil production, and even reserves. Therefore, microbial growth modelling is necessary in order to forecast the performance of MEOR-implemented well. The objective of this study is to determine the most representative microbial growth model for the microbe used in Field X by fitting existing empirical models (Logistic, Gompertz, and Richards) by using grofit package in R program and analyzing the R-squared (R2) and Residual Sum of Squared (RSS) values. Hence, forecasting future production performance could be performed by employing Darcy equation. Related parameters such as viscosity and skin need to be adjusted since MEOR contributes to oil viscosity reduction and wellbore clean-up. In order to gain the accurate prediction, oil viscosity reduction model over time is constructed using laboratory data. From the microbial population monitoring in Field X (TM-122 and TM-125 well), Gompertz model is considered to describe microbial growth in reservoir. MEOR treatment resulted the reduction of oil viscosity for about 23% and 15% which supported by laboratory data of TM-125 and TM-122. By adjusting some parameters, Darcy equation is suitable to forecast future production performance of MEOR-implemented well with error less than 5%. From this study, the primary mechanisms of MEOR in Field X are viscosity reduction, near wellbore damage removal, and IFT reduction.