Monitoring Of Bacterial Community Dynamics Nutrition Biostimulation in Well X South Sumatera Based On Ilumina Sequencing

• Main Author: Nur Afifah - Nim: 10414019 , Lulu
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/28657
• Institution: Institut Teknologi Bandung

Bistimulation is one of microbial enhanced oil recovery (MEOR) methods to improve oil production with injection of nutrition to oil reservoir. Nutrition addition will stimulate indigenous hydrocarbonoclastic microbes and can change microbial community dynamics in oil reservoir. This research was aim to ‘memantau’ microbial dynamics in oil reservoir after biostimulation. Nutrition added are molasses 7.2%, DAP 0.28%, and NPK 0.307%. Microbial extracted from 5-10 L formation water before and after biostimulation in six weeks. Pellets are analyzed by Illumina Hiseq Sequencing to observe the growing microbes because of biostimulation. Hydrocarbon degradation analyzed by column chromatography test. The correlation between physical characteristics with microbial dynamics analyzed statistically by Principal Component Analysis (PCA). <p align="justify">According to QIIME analysis for microbial dynamics, the diversity of reservoir X was high with 12 bacteria phylum and 1 archaea phylum detected. Firmicutes, Proteobacteria, and Bacteroidetes was the dominant phylum observed during the monitoring. Before the injection, dominant bacteria were hydrocarbonoclastic bacteria such as Bacillus, Pseudomonas, and Halomonas. After biostimulation, microbial diversity increased with the addition of fermentative, sintrophy, methanogenic, and sulphate reducing bacteria beside the growth of hydrocarbonoclastic bacteria. Hydrocarbonoclastic bacteria dominated again since week 4. Bacillus was seen in all time of the biostimulation. It known to degraded saturated, aromatic, resin and asphaltene fraction of hydrocarbon. According to column chromatography analysis, saturated, aromaric and resin fraction increased during the monitoring process up to 47%, 17.5% and 55% along with the degradation of asphaltene fraction up to 38.5%. According to PCA analysis, Rhodocyclales, Corynebacterium, Enterococcus, Desulfosporosinus, Marinobacterium was the bacteria that have positive contribution during monitoring. Based on column chromatography analysis, asphaltene degraded 38.5% whereas other fraction such as saturated, aromatic, and resin increased 47%, 17,5%, and 55%. Biostimulation can reduced pH from 9.16 to 6.3, viscosity reduced 18.4% and IFT reduced 32.7%. <p align="justify"> <br />