#TITLE_ALTERNATIVE#

• Main Author: FAHD (NIM : 10414030), AZHAR
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/25987
• Institution: Institut Teknologi Bandung

<p align="justify"> Microbial enhanced oil recovery (MEOR) is an oil extraction technology by utilizing microorganisms biomass, biopolymer, biosurfactant, acid, gas, solvent and hydrocarbon degradation to increase oil recovery in less productive oil wells. Previous studies have shown that the combination of molasses, NPK, and (NH4) 2HPO4 can stimulate bacterial growth and also decrease viscosity and interfacial tension of oil in laboratory scale (Astuti and Dewi, 2014). Based on these results, nutrition biostimulation is done at Y oil wells in South Sumatra. This study was conducted to change the quality of petroleum-fluid and bacterial abundance in Y oil wells for three months. Changes in abundance of aerobic, anaerobic and SRB bacteria (sulfate reducing bacteria) were examined using Total Plate Count method, anaerobic bacteria and SRB were cultivated using Hungate technique. Oil chemical and physical characteristics measured with viscosity measurements and interface voltages (IFTs) as well as analysis of oil fraction compounds using GC-MS (Gas Chromatography - Mass Spectometry). The oil fluid sampling is conducted once every three days in the first month and seven times in second and third months. Based on the results of bacterial abundance analysis for 2 months there was an increase of total aerobic bacteria abundance from 7,53 x 102 CFU / ml to 2,3 x 105 CFU / ml with the highest amount reaching 1,17 x 107 CFU / ml, total anaerobic bacteria abundance from 2.75 x 101 CFU / ml to 7.6 x 102 CFU / ml. The increase of bacterial abundance successfully changed the physical-chemical condition of petroleum, there was a decrease of 24,41% viscosity value before and after that from 77,846 cP to 58,841 cP, and IFT value decrease equal to 46,29% from 28,3 dyne / cm to 15.2 dyne / cm. The production performance can be seen from % water cut data wich decreased from the initial value in the range of 99% to remain at 92% range. Also, the MEOR biostimulation process is not able to induce SRB growth which is seen from SRB abundance value which only reach 1.5 x 102 CFU / ml. <p align="justify">