Boosting nutrient recovery from AnMBR effluent by means of electrodialysis technology: Operating parameters assessing.

This work describes a comprehensive assessment of operating parameters of a bench-scale electrodialysis (ED) plant for nutrient concentration from an Anaerobic Membrane BioReactor (AnMBR) effluent. The ED bench-scale plant serves a dual purpose. Firstly, to generate a concentrated stream with a high nutrient content, and secondly, to produce high-quality reclaimed water in the diluted stream, both sourced from real wastewater coming from the effluent of an AnMBR. Two sets of experiments were conducted: 1) short-term experiments to study the effect of some parameters such as the applied current and the type of anionic exchange membrane (AEM), among others, and 2) a long-term experiment to verify the feasibility of the process using the selected parameters. The results showed that ED produced concentrated ammonium and phosphate streams using a 10-cell pair stack with 64 cm2 of unitary effective membrane area, working in galvanostatic mode at 0.24 A, and operating with an Acid-100-OT anionic exchange membrane. Concentrations up to 740 mg/L and 50 mg/L for NH 4 –N and PO 4 –P, respectively, were achieved in the concentrated stream along with removal efficiencies of 70% for ammonium and 60% for phosphate in the diluted stream. The average energy consumption was around 0.47 kWh·m−3. [Display omitted] • ED can effectively concentrate NH 4 -N and PO 4 -P from AnMBR real effluent. • Lower current values are preferable when working with real urban wastewater. • Selecting an adequate AEM is crucial due to low PO 4 -P recovery efficiencies. • Increasing the number of cell pairs in the ED stack enhances recovery and removal efficiencies. • Determining the most suitable parameters is critical for reducing energy consumption. [ABSTRACT FROM AUTHOR]