Bioelectrochemical sulfate reduction enhanced nitrogen removal from industrial wastewater containing ammonia and sulfate

Abstract

Abstract Low organic carbon‐to‐nitrogen ratio and existing sulfate (SO 4 2− ) in industrial wastewater limited nitrogen removal. Coupling SO 4 2− reduction with sulfide autotrophic denitrification provides a novel strategy. Herein, bioelectrochemical sulfate reduction was coupled with heterotrophic sulfate reduction to drive sulfide autotrophic denitrification. In this coupled system, total nitrogen (TN) removal efficiency was increased from ~25% to ~85% by inputting −45 mA electricity. With the help of supplying electrons to denitrification through SO 4 2− reduction, coulomb efficiency was improved to 61.5%. Also, bioelectrochemical sulfate reduction could improve sulfur recovery and thus increase TN removal efficiency. Furthermore, through tuning turnover numbers of SO 4 2− , high TN removal efficiency can be obtained at various concentrations of SO 4 2− . Moreover, main functional bacteria in this system were identified. Finally, ~75% TN removal efficiency was achieved with real wastewater in this system. Overall, this work offered a new approach for efficient nitrogen removal from industrial wastewater containing SO 4 2− .

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Identifiers

DOI

10.1002/aic.17309

Journal

AIChE Journal

Year

2021