Nutrient Concentration via Electrodialysis from AnMBR effluent for Subsequent Recovery: Energy Consumption and System Performance Optimization

This study assesses different operating modes of a bench-scale electrodialysis (ED) plant for nutrient concentration from an aerated Anaerobic Membrane Bioreactor (AnMBR) effluent. Long-term and short-term ED tests were conducted to optimize system performance with two aims: generate a concentrated stream with a high nutrient content, and produce high-quality reclaimed water. Operational modes in one stage and two-stages, total membrane area, working/relaxation periods and influent nutrient concentrations were evaluated. Results showed a better ED system performance operating in two-stages, with 30 cell pairs and with higher influent nutrient concentrations. Concentrations up to 1005 mgNH4-N/L and 117 mgPO4-P /L in the concentrated stream and low to 3.5 mgNH4-N/L and 0.7 mgPO4-P /L in the diluted stream were achieved in long-term tests.