Perpustakaan Digital ITB

Waterflooding is one of the most used oil recovery methods and has been used since the late 1800s. The injected water usually contains suspended solids and oil droplets that may damage the areas around the wellbore. It is essential to maintain the water quality to prevent any problems that could happen during the waterflooding process; therefore, a proper monitoring system is required. Researchers quote that the Hall plot has proved to be the most effective method for waterflood surveillance, primarily when it is used with its derivative, the Izgec plot. Detecting early problems in waterflood operations can be beneficial so preventive and restorative actions can be prepared earlier. This paper presents a demonstrative use of the Izgec plot as waterflood surveillance in an actual field. While also offers an automation script for constructing Izgec plot using Python programming language. Based on the study carried out on two injection wells of X Field, both manual and automated calculation provides the same result, the indication of plugging in the early injection period and the indication of fracturing in the late injection period. This paper also highlights the estimated wellhead injection pressure when fracturing happens. It converts that into bottom-hole pressure using single-phase liquid pressure drop correlation to obtain the estimated formation fracturing pressure, which is extremely useful for future references for additional injection wells.