Vibroseismic Stimulation for Bacterial Core Flooding Simulation by Using Handil Oil Isolate Geobacillus toebii R-32639 and R-32653 to Artificial Core

Abstract

This advanced research related to combination of MEOR (Microbial Enhanced Oil Recovery) and vibroseismic stimulation conducts laboratory scale simulation of indigenous bacterial injection into laboratory scale reservoir model by using artificial core. Previous study results two bacterial isolates from Handil Field, identified as Geobacillus toebii R-32639 and R-32653, and could increase recovery factor from 40% to 60%. This research aims to analyze the combination of bacterial injection with vibroseismic stimulation on the recovery factor. Bacterial isolates that used for injection is an 1:1 ratio mixed culture of Geobacillus toebii R-32639 and R-32653 with 10 cells/mL density. Artificial core permeability value that were used for bacterial injection is ranged from 5 mD to 200 mD and porosity ranges from 24% to 49%. Oil saturated artificial core that has been applied with waterflooding were then injected  ith  acteria and observed the recovery factor after incubation for 7 days at 55^oC. The results obtained combined with the incremental recovery  factor from vibroseismic  stimulation.  Photomicrographs investigation by SEM (Scanning Electron Microscope) is performed to  confirm the presence of bacteria in artificial core. Laboratory study resulted that waterflooding process yield a recovery factor between 14.3%-83.3%. Incubation for 7 days after bacterial injection on artificial core with permeability range of 5 mD-15 mD; 15 mD-50  mD; and 50 mD-200 mD are 13.7%-60%, 13.1%-45.7%, and 22.6%-86.6% respectively. Vibroseismic stimulation with 15 Hz frequency and waterflooding on artificial cores from reached 18.6% of additional recovery factor. Artificial core porosity and permeability values increased by 27.4% and 34.5%. Injected bacteria can attach and survive on artificial cores, indicated by the presence of bacteria on the SEM photomicrograph.