Comparison of PPCPs removal on a parallel-operated MBR and AS system and evaluation of effluent post-treatment on vertical flow reed beds

摘要

The presence in the aquatic environment of xenobiotics such as Pharmaceutical and Personal CarenProducts (PPCPs) has emerged as an issue of concern. Upgrading sewage treatment quality withnmodern technologies such as Membrane Bioreactors (MBRs) and/or implementing a further post-ntreatment might mitigate the release of xenobiotics into surface waters. The performance of twonprocesses treating municipal sewage, a MBR and an Activated Sludge (AS) unit, have been comparednin terms of PPCPs removal. Moreover, their effluents were treated using vertical flow reed beds. Bothnsystems were operated under similar conditions, more specifically Hydraulic Retention Time (HRT),nmaintained at 8 hours, and Sludge Retention Time (SRT) set at 6 and 20 days. Pharmaceuticals belongnto therapeutic groups such as antiepileptics (carbamazepine) and analgesics (ibuprofen, naproxen,ndiclofenac), whereas the personal care products are musk fragrances (galaxolide and tonalide).nXenobiotics removals achieved in the MBR showed better results, particularly for the acidic drugsnibuprofen (87% vs. 50%) and naproxen (56% vs. 6%) operating at low SRT. After filtration throughnvertical flow reed-beds, PPCPs content in effluents was decreased, below 1 ppb in most cases,nimproving the effluent quality and confirming reed-beds as an interesting low cost alternative innorder to attenuate xenobiotics contamination.