Dynamics, mechanisms and countermeasures of nitrous oxide emission at a full scale sewage treatment plant

2015 Fiscal Year Final Research Report

• Project/Area Number: 25289173
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Civil and environmental engineering
• Research Institution: Kochi University
• Principal Investigator: FUJIWARA TAKU 高知大学, 自然科学系, 教授 (10314981)
• Co-Investigator(Kenkyū-buntansha): TSUTSUI HIROFUMI 東京工科大学, 応用生物学部, 助教 (70620649) ; NISHIMURA FUMITAKE 京都大学, 大学院工学研究科, 准教授 (60283636) ; TERADA AKIHIKO 東京農工大学, 大学院工学研究院, 准教授 (30434327)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 亜酸化窒素 / 実下水処理施設

Outline of Final Research Achievements

Nitrous oxide (N2O) emission at a full scale wastewater treatment plant (WWTP) was investigated, in which the same influent sewage was treated by three different activated sludge systems in parallel, to clarify dynamics, mechanisms and countermeasures of the emission. Lower dissolved (D-) N2O concentrations were observed in an anoxic/oxic process with three-step feeding, while higher concentrations were detected at third oxic tank in an anoxic/oxic process. It was also found that sudden decrease of dissolved oxygen concentration induced N2O production in the tank. Evaluation of functional genes associated with N2O production and decomposition indicated that almost no N2O reduction occurred in the oxic tank and dynamics of N2O producing bacteria should be studied more in detail. In conclusion, aeration management is important to mitigate N2O emission from a full scale WWTP.

Free Research Field

用排水システム