Development of a Hybrid System for Simultaneous Removal of Nutrients and Heavy Metals from Wastewater

The simultaneous presence of nutrients (nitrogen and phosphorus) and heavy metals in wastewater poses significant environmental challenges, including eutrophication and toxicity. Conventional treatment systems often fail to address these pollutants concurrently due to their differing chemical properties. This study presents a hybrid system integrating constructed wetlands (CWs), microbial fuel cells (MFCs), and biochar-based bio-sorption to achieve efficient removal of nutrients and heavy metals from industrial and municipal wastewater. A pilot-scale system was tested, achieving removal efficiencies of 87% for chemical oxygen demand (COD), 82% for total nitrogen (TN), 90% for total phosphorus (TP), and over 92% for heavy metals (Cu, Zn, Pb, Cd). Metagenomic analysis revealed mi- microbial synergistic interactions, while the MFC component generated bioelectricity, enhancing sustainability. The system’s low cost and robustness make it a promising solution for wastewater treatment in resource-constrained settings.