Phycoremediation of municipal wastewater: Removal of nutrients and contaminants of emerging concern

Highlights: • A pilot-scale high-rate algal pond was used to treat municipal wastewater. • Nutrients removal was 76% for total nitrogen and 41% for total phosphorus. • CEC removal ranged from 51% to 92%. • CEC treatment efficiency comparable to activated sludge High-rate algal ponds (HRAP) are an alternative to conventional wastewater treatment that could contribute to the circular economy by valorising reclaimed water and algal biomass. This short communication presents the removal of nutrients and contaminants of emerging concern (CEC) in a pilot-scale HRAP treating primary municipal wastewater. Average removal of total organic carbon, total nitrogen, NH₄-N, total phosphorus and PO₄-P, was 67%, 76%, 87%, 41% and 46%, respectively. In addition, 12 CECs were detected in the influent and five in the effluent. Removals were as follows: naproxen 60%, ibuprofen 51%, methylparaben 92%, 2,4-dihydroxybenzophenone 76% and oxybenzone 80%, and are comparable with literature data for conventional wastewater treatment and other HRAPs. In conclusion, studies of nature-based solutions such as HRAPs show encouraging results but need further research to understand the risks and requirements of safe wastewater and biomass reuse.