A microbial ecological approach to unravel the sediment remediation mechanism by sediment microbial fuel cells

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K15938
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 41030:Rural environmental engineering and planning-related
• Research Institution: National Institute for Environmental Studies
• Principal Investigator: Takemura Yasuyuki 国立研究開発法人国立環境研究所, 地域環境研究センター, 特別研究員 (10837199)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: 底質改善 / 微生物燃料電池 / メカニズム解析 / 微生物生態

Outline of Final Research Achievements

To investigate the sediment remediation mechanisms by sediment microbial fuel cells (SMFC), lab-scale experiments was conducted for the sediments collected from sea, river, freshwater lakes, and park ponds. Sediment pore water quality of the both closed-circuit conditions (active as SMFC) and open-circuit conditions (OC) were monitored to investigate the relationship between electron transfer and phosphorus concentration. As a result, phosphorus concentration decreased in freshwater SMFCs than that in OCs. We presumed that the phosphorus may have been electrochemically attracted on the anode in the sediments. Furthermore, Methanoperedens, an anaerobic methane oxidation archaeon capable of generating electricity dominates only in freshwater SMFCs. Suggesting that, methane in the sediment may have been oxidized to promote electricity resulting that electrochemically adsorption of phosphorus was enhanced.

Free Research Field

地域環境研究

Academic Significance and Societal Importance of the Research Achievements

富栄養湖沼などの底質改善技術として原位置処理が可能な堆積物微生物燃料電池（SMFC）を提案し、本研究により、電極（アノード）の電気化学的作用でリンが吸着されることによって、底泥からのリン溶出が抑制されるものと推察された。また、SMFCを適用した複数種の淡水系の底泥において、発電能を持つことが知られている嫌気性メタン酸化古細菌（Methanoperedens属）が優占したことから、この微生物の機能と発電や底質改善効果との関係性をより詳細に把握することで技術の効率化に繋げられると考えられた。