#TITLE_ALTERNATIVE#

• Main Author: YUNITA HALIM (NIM. 106 03 002), AMALIA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/11789
• Institution: Institut Teknologi Bandung

</i><b>Abstract: </b><i><p align="justify"> Microbial enhanced oil recovery (MEOR) is a tertiary recovery technology which has been established as a cost effective solutions for declining oil production. The MEOR team from Microbiology Laboratorium in SITH-ITB has a lot of hidrocarbonoclastik bacteria culture collection from MEOR dan bioremediation research. This experiment is conducted to test some hidrocarbonoclastik bacteria from the culture collection which has been proven to be potential as indigenous bacteria in MEOR to be applied as non-indigenous bacteria. In this experiment, five culture collection of bacteria which are isolated from Handil Field (<u>Flavimonas oryzihabitans</u>, <u>Amphibacillus xylanus</u>, <u>Bacillus polymyxa</u>, <u>Bacillus macerans</u>, <u>Clostridium butyricum</u>) and also the mix culture of the bacteria are applied to crude oil from Jatibarang reservoir. The first step of this experiment is bacteria subculture and morfological observation to check the purity of the bacteria used. After that the bacteria need to be activated to reduce the lag phase of the bacterial growth. They were activated and adapted on gradually increased temperature (40ºC, 45ºC, 50ºC, 55ºC, 60ºC, 65ºC, 70ºC, 75ºC, 80ºC, 85ºC, 90ºC) in SMSSe medium. Later they were activated and adapted on gradually increased oil concentration (2%, 5%, 10%, 15%, 20%) in recovery medium. The bacterial growth curve was made after the activation and adaptation process to determine the optimum time of the bacteria which can be used as the inoculum. Then the Jatibarang crude oil in recovery medium was injected with bacteria inoculum and incubated for seven days. The measurement of oil’s physical characterization (viscosity, density, interfacial tension and gas production) and oil composition was done after the incubation time. The bacterial growth curve shows that the µ max of <u>F. oryzihabitans</u> is 0,0183 h^-1 which is reach at 12 hours, µ max of <u>A. xylanus</u> is 0,0121 h^-1 which is reach at 18 hours, µ max of <u>B. polymyxa</u> is 0,0204 h^-1 which is reach at 18 hours, µ max of <u>B. mecerans</u> is 0,0186 h^-1 which is reach at 18 hours, µ max of <u>C. butyricum</u> is 0,0183 h^-1 which is reach at 12 hours. The viscosity decrease ranging from 0,042 to 0,407 centi Poise (the best decrease is by <u>A. xylanus</u>). The density decrease ranging from 0,007 to 0,112 gram/mL (the best decrease is by <u>F. oryzihabitants</u>). The interfacial tension decrease ranging from 0,54 to 4,18 dyne/cm (the best decrease is by <u>C. butyricum</u>). Gas production varies from 0,7 to 1,05% (the highest gas production is by <u>B. polymixa</u>). The result of oil composition by Gas Chromatography (GC) method shows that the crude oil has been degradated by bacteria. All of the bacteria and the mix culture of the bacteria can degradate the short and the medium chain of n-alkene (C₃-C₁₈), and several different chain of the long n-alkene. The long n-alkene degradation by <u>F. oryzihabitans</u> is on C₂₂, by <u>A. xylanus</u> is on C_22-23, and C₂₅-C₂₇, by <u>B. polymyxa</u> is on C₂₂ dan C₂₇, by <u>B. macerans</u> is on C₂₈, by <u>C. butyricum</u> is on C₂₆-C₂₇, by mix culture is on C_28-29. This result shows that all of the bacteria from Handil Field are potential to be used as non-indigenous bacteria for Jatibarang crude oil in laboratory scale. Further study of bacterial growth in larger scale (bioreactor) and the composition of bacteria mix culture is needed for field application.</p>