Bioelectrochemical Treatment of Sulfate-Rich Mining Wastewater Using Microbial Fuel Cell Technology

Abstract

Sulfate-rich mining wastewater generated from mining and metallurgical operations poses significant environmental challenges due to its high sulfate concentration, acidity, and dissolved metal content. This study investigates the bioelectrochemical treatment of sulfate-rich mining wastewater using microbial fuel cell (MFC) technology for simultaneous wastewater remediation and bioelectricity generation. The research focuses on evaluating sulfate reduction efficiency, power production performance, and microbial activity under varying operational conditions. Experimental analyses were conducted to examine the influence of hydraulic retention time, external resistance, electrode material, wastewater composition, pH, and organic substrate concentration on treatment effectiveness and electrochemical behavior. Results demonstrated that the microbial fuel cell system effectively promoted sulfate reduction through the metabolic activity of electroactive and sulfate-reducing microorganisms, resulting in substantial decreases in sulfate concentration and improvement in wastewater quality. Simultaneously, electron transfer processes within the bioelectrochemical system enabled stable electricity generation, indicating the dual-function capability of the technology. The anodic microbial community facilitated oxidation of organic substrates, while cathodic reactions supported sulfate conversion and contaminant removal. Kinetic and electrochemical analyses revealed that electrode conductivity, microbial biofilm formation, and substrate availability strongly influence treatment efficiency and power density output. The system also contributed to reduced sludge generation and lower chemical consumption compared with conventional physicochemical treatment methods. Furthermore, the integrated treatment approach demonstrated potential for sustainable management of mining wastewater through energy recovery and reduced environmental impact. The findings highlight the applicability of microbial fuel cell technology as an innovative and environmentally sustainable solution for treating sulfate-rich industrial effluents and advancing resource-efficient wastewater remediation practices.