Enhanced Oil Recovery by Methane Fermentation of Petroleum - Verification of the Potential for Creating a CO2-Free Hydrogen Source

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05347
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 31020:Earth resource engineering, Energy sciences-related
• Research Institution: Gifu University
• Principal Investigator: Nakamura Kohei 岐阜大学, 応用生物科学部, 准教授 (40456538)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: メタン発酵 / MEOR / 難培養性微生物 / 嫌気的アルカン分解 / メタゲノム

Outline of Final Research Achievements

A petroleum-degrading methanogenic microbial community was established using a mixed alkane solution and diesel oil. There were three dominant species, an acetate-utilizing methanogenic archaea and two species of alkane-degrading bacteria. These two bacteria may have metabolized alkanes of different chain lengths by using their own alkylsuccinate synthase. Metagenomic analysis and literature reviewing indicated that heterotrophic bacteria may have contributed to methane fermentation by utilizing organic matter in the system, rather than being directly involved in alkane degradation. We were unable to evaluate the effects of petroleum on the methane fermenting microbiota under high-pressure CO2 conditions, suggesting that removal of oxygen in CO2, selection of cultivation vessels for long-term incubation, and measures to shorten incubation time are needed.

Free Research Field

応用微生物学　微生物生態学

Academic Significance and Societal Importance of the Research Achievements

アルカン分解メタン発酵は，油田に残存する石油エネルギーを回収する手法として提唱されている。嫌気性アルカン分解菌のいくつかが分離されているが，メタン生成アーキアと共生できるアルカン分解菌は１株のみである。一方，メタゲノム解析によってアルカン分解菌の性状が明らかになりつつある。本研究の科学的成果は，アルカン分解菌のメタゲノム解析等からアルカン分解に関わるAss遺伝子の多様性を明らかにしただけでなく，アルカン分解細菌に代謝可能なアルカン鎖長スペクトラムが存在することを明らかにしたことである。