Evaluating the opportunities for mainstream P-recovery in anaerobic/anoxic/aerobic systems

Mainstream P-recovery can help wastewater treatment plants (WWTPs) to effectively maintain good enhanced biological phosphorus removal (EBPR) while helping to recover P. In this study, a pilot-scale anaerobic-anoxic-aerobic (AO) process was operated for simultaneous COD/N/P removal and P-recovery un...

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Detalles Bibliográficos
Autores: Cheng, Mengqi, Zhang, Congcong|||0000-0003-3693-4705, Guisasola, Albert|||0000-0002-3012-7964, Baeza, Juan Antonio|||0000-0003-1290-1669
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:287790
Acceso en línea:https://ddd.uab.cat/record/287790
https://dx.doi.org/urn:doi:10.1016/j.scitotenv.2023.168898
Access Level:acceso abierto
Palabra clave:Chemical equilibrium model
Enhanced biological phosphorus removal (EBPR)
Nutrient removal
P recovery
Descripción
Sumario:Mainstream P-recovery can help wastewater treatment plants (WWTPs) to effectively maintain good enhanced biological phosphorus removal (EBPR) while helping to recover P. In this study, a pilot-scale anaerobic-anoxic-aerobic (AO) process was operated for simultaneous COD/N/P removal and P-recovery under different operational conditions. The operation with conventional extraction of waste activated sludge (WAS) from the aerobic reactor was compared to the mainstream P-recovery strategy of WAS extraction from the anaerobic reactor. Successful nutrient removal was obtained for both scenarios, but the anaerobic WAS extraction results improved polyphosphate accumulating organisms (PAOs) activity by increasing almost 27 % P concentration in the anaerobic reactor. WAS fermentation was also evaluated, showing that anaerobic WAS required only 3 days to reach a high P concentration, while the aerobic WAS fermentation required up to 7 days. The fermentation process increased the amount of soluble P available for precipitation from 24.4 % up to 51.6 % in the fermented anaerobic WAS scenario. Results obtained by precipitation modelling of these streams showed the limitations for struvite precipitation due to Ca interference and Mg and NH as limiting species. The optimum precipitation scenario showed that P-recovery could reach up to 51 % of the input P, being 90 % struvite.