Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano, 77, 38123 Trento, Italy.
Bioresour Technol. 2013 Dec;149:398-405. doi: 10.1016/j.biortech.2013.09.099. Epub 2013 Sep 29.
Vertical subsurface-flow constructed wetlands at pilot-scale have been applied to treat high hydraulic and organic loads by implementing the following configurations: (1) intermittent recirculation of the treated wastewater from the bottom to the top of the bed, (2) intermittent artificial aeration supplied at the bottom of the bed and (3) the combination of both. These configurations were operated with a saturated bottom layer for a 6h-treatment phase, followed by a free drainage phase prior to a new feeding. COD removal efficiency was 85-90% in all the configurations and removed loads were 54-70 gCOD m(-2)d(-1). The aerated and recirculated wetland resulted in a higher total nitrogen removal (8.6 gN m(-2)d(-1)) due to simultaneous nitrification/denitrification, even in the presence of intermittent aeration (6.8 Nm(3)m(-2)d(-1)). The extra investment needed for implementing aeration/recirculation would be compensated for by a reduction of the surface area per population equivalent, which decreased to 1.5m(2)/PE.
（1）从床底部到顶部间歇性回流处理后的废水，（2）在床底部间歇性人工曝气，以及（3）两者结合。这些配置采用饱和底层进行 6 小时处理阶段，然后在新进料前进行自由排水阶段。所有配置的 COD 去除效率均为 85-90%，去除负荷为 54-70 gCOD m(-2)d(-1)。由于同时硝化/反硝化作用，充气和再循环湿地的总氮去除率更高（8.6 gN m(-2)d(-1)），即使存在间歇性曝气（6.8 Nm(3)m(-2)d(-1)）也是如此。实施曝气/再循环所需的额外投资将通过减少每个人口当量的表面积来补偿，表面积减少到 1.5m(2)/PE。
