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[Display omitted] • Magnesite tailings and wastewater were resource utilization by the BMED process. • H+ for Mg leaching and OH– for struvite formation are provided by water splitting. • The P recovery ratios can reach approximately 98% under various conditions. • The nitrogen (NH 4 +-N) was recovered as struvite instead of being released. • The purity of struvite can reach as high as 97.1%. In this study, the feasibility of simultaneously recovering Mg, nitrogen (NH 4 -N) and phosphorus (P) from magnesite tailings and freshwater aquaculture have been confirmed through the bipolar membrane electrodialysis with a processing unit for the first time. The H+ required for Mg2+ leaching and OH– needed for struvite formation can be provided by the BMED system. The results indicate that adding 0.3 mol/L initial HNO 3 could enhance the Mg2+ leaching and reduce the energy consumption (EC). The recovery ratios of P and NH 4 -N reached to about 97.9 % and 52.3 %, respectively, while the EC was about 0.051 kWh/L. Increasing the tailing dosage shortened the required treatment time and reduced the EC. Increasing the current density significantly enhanced nutrient recovery rate, but accompanied by an increase in EC. A longer treatment time is necessary for treating larger volumes of wastewater, while a P recovery ratio of approximately 99 % can be achieved. Calcium is the predominant impurity. The purity of struvite was enhanced through a multi-batch process, achieving a maximum of 97.1 % at the third time. This study provides new insights into the resourceful treatment of tailings and wastewater. [ABSTRACT FROM AUTHOR]