FIRST SUCCESSFUL APPLICATION OF MICROBIAL ENHANCEMENT OF OIL RECOVERY IN VIETNAM

摘要

Over hundred samples were taken and analysed from injection, production wells and sea water of Vung Tau oil field (Southern Vietnam). Among the isolated microorganisms, we screened three bacteria strains of high temperature tolerant and long chain hydrocarbon-utilizing: D.107T°, NBT°, BE3T°and 6 gas-forming bacteria: C122, C124, C138, C1107, C114, C164. Bacteria were identified by API 20NE, API 50CHB, API 50CHL, API 20A and morphological observation. They were capable of reducing oil viscosity and increasing gas-forming in stratum modelling tests (100atm-110℃; 100atm-130℃; 260atm- 110℃). The field tested show that bacteria impacted positively on gas, oil yield. CH4 gas increased 10- 12%. Water/oil ratio fell from 62% to 50%. The oil yield of well 24 stabled at 20-23 tones/day during 10 months. The oil yield of well 38 gained 20 tones/day incomparision with 8 tones/day at the beginning.