Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences

Just Accepted

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Performance of a large-scale wetland treatment system in treating tailwater from a sewage treatment plant

Siyuan Song , Benfa Liu , Wenjuan Zhang , Penghe Wang , Yajun Qiao , Dehua Zhao , Tangwu Yang , Shuqing An , Xin Leng

Abstract

Water quality standards pertaining to effluents from sewage treatment plants (STPs) in China have become more stringent, requiring upgrading of STPs, entailing huge capital expenditures. Wetland treatment systems (WTSs) are a low-cost and high-efficiency approach for deep purification of tailwater from STPs. The Hongze WTS (HZ-WTS), a large-scale surface-flow constructed wetland (SF CW), with a total area of 55.58ha and a treatment capability of 4 × 104m3d-1, was built for the disposal of tailwater from STPs. The objective of this study was to evaluate the performance of HZ-WTP with regards to seasonal variations and comparisons of treatment costs of other STPs. Its intra-annual performance was evaluated in 2013 using online monitoring. HZ-WTS showed significant removal efficiencies for ammonia nitrogen (NH4+-N), chemical oxygen demand (COD) and total phosphorus (TP) levels (56.33 ± 70.44%, 55.64 ± 18.58% and 88.44 ± 22.71%, respectively), while significant seasonal variation was observed in the NH4+-N removal efficiency. In addition, the average treatment cost was 0.17 yuan/m3, significantly lower than the corresponding value for other STPs. Therefore, WTSs are recommended for use with STPs in order to improve wastewater quality in a cost-effective manner.

MF17203  Accepted 04 January 2018

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