This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.
Performance of a large-scale wetland treatment system in treating tailwater from a sewage treatment plant
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
© CSIRO 2018