Sustainable Treatment of Antibiotic Wastewater Using Combined Process of Microelectrolysis and Struvite Crystallization

The aim of this study was to investigate the synergistic effects of the process of iron-carbon microelectrolysis (ICME) followed by struvite (MAP) crystallization on treating antibiotic wastewater. Characteristics of ICME effluent depended mainly on the iron to carbon mass ratio (Fe/C). The optimum reaction conditions of Fe/C ratio of 2:1 and reaction time of 90 min were observed. The ICME effluent was further treated by MAP crystallization using Na2HPO4 center dot 12H2O and MgCl2 center dot 6H(2)O as precipitation agents. The results showed that, the Mg2+/NH4+-N/PO43--P molar ratio of 1:1:1 and pH 8.5, were suitable for the crystallization process, which could obtain high-quality MAP containing 5.18 % N, 10.23 % Mg, and 13.83 % P. Optimal total removal rate of COD and NH4+-N removal rate achieved 84.6 and 89.9 %, respectively. The economic evaluation of NH4+-N recovery by the synergistic process was also conducted, indicating that the synergistic process had the potential to benefit COD emission reduction and nitrogen recovery.