Sustainable Phosphate Capture from Urban Wastewater Treatment Plants Towards a Nutrient Recovery and Water Reuse Strategy
Source abstract
Abstract
This study proposes and evaluates a two-step phosphorus (P) recovery strategy that combines chemical precipitation with adsorption to comply with the updated EU Urban Wastewater Treatment Directive (Directive (EU) 2024/3019), which sets stricter limits on nutrient discharge and promotes resource recovery. The objective was to enhance the P removal efficiency beyond that achieved by conventional precipitation. A laboratory-scale design of experiments was conducted using real wastewater with an initial P concentration of 10 mg P/L post-precipitation and was extended to 1 and 40 mg P/L to assess broader applicability. The optimal lab-scale conditions (30 cm bed height and 5 mL/min flow rate) resulted in a saturated bed fraction (FSB) of 0.425 and a breakthrough time of 126 min. The process was successfully scaled up to a column with a height of 60 cm and a diameter of 4 cm, achieving a higher FSB (0.764), improved adsorption capacity (84.1 mg P/kg), and reduced unused bed (40%). The integrated system maintained effluent P levels below 0.5–0.7 mg P/L for over 400 min, demonstrating regulatory compliance and operational reliability. These findings confirmed the feasibility and scalability of combining precipitation with adsorption for enhanced P recovery in wastewater treatment systems.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Phosphorus and nutrient management
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Chemical Engineering, CERES, University of Coimbra, 3030-790 Coimbra, Portugal
Associate Laboratory TERRA, LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Funding
Fundação para a Ciência e Tecnologia (FCT) · FCT · LEAF—Linking Landscape, Environment, Agriculture and Food Research Centre · Associate Laboratory TERRA
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