Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
Catalan Institute for Water Research (ICRA), Emili Grahit Street, 101, H(2)O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain; REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
Water Res. 2015 Mar 15;71:1-10. doi: 10.1016/j.watres.2014.12.032. Epub 2014 Dec 30.
A continuous, on-line quantification of the nitrous oxide (N2O) emissions from a full-scale sequencing batch reactor (SBR) placed in a municipal wastewater treatment plant (WWTP) was performed in this study. In general, N2O emissions from the biological wastewater treatment system were 97.1 ± 6.9 g N2O-N/Kg [Formula: see text] consumed or 6.8% of the influent [Formula: see text] load. In the WWTP of this study, N2O emissions accounted for over 60% of the total carbon footprint of the facility, on average. Different cycle configurations were implemented in the SBR aiming at reaching acceptable effluent values. Each cycle configuration consisted of sequences of aerated and non-aerated phases of different time length being controlled by the ammonium set-point fixed. Cycles with long aerated phases showed the largest N2O emissions, with the consequent increase in carbon footprint. Cycle configurations with intermittent aeration (aerated phases up to 20-30 min followed by short anoxic phases) were proven to effectively reduce N2O emissions, without compromising nitrification performance or increasing electricity consumption. This is the first study in which a successful operational strategy for N2O mitigation is identified at full-scale.
本研究对置于城市污水处理厂（WWTP）中的全规模序批式反应器（SBR）中的氧化亚氮（N2O）排放进行了连续、在线定量。一般来说，生物污水处理系统的 N2O 排放量为 97.1 ± 6.9 g N2O-N/Kg [Formula: see text] 消耗或进水 [Formula: see text] 负荷的 6.8%。在本研究的 WWTP 中，N2O 排放量平均占设施总碳足迹的 60%以上。为了达到可接受的出水值，在 SBR 中实施了不同的循环配置。每种循环配置均由不同时长的曝气和非曝气阶段组成，由固定的氨氮设定点控制。曝气阶段时间较长的循环会产生最大的 N2O 排放，从而增加碳足迹。证明间歇曝气（曝气阶段长达 20-30 分钟，随后是短暂的缺氧阶段）的循环配置可有效减少 N2O 排放，而不会影响硝化性能或增加用电量。这是首次在全规模上确定了成功的 N2O 减排操作策略的研究。
