Electroactive bacterial community augmentation enhances the performance of a pilot scale constructed wetland microbial fuel cell for treatment of textile dye wastewater

This study evaluated the effect of bioaugmentation of a newly enriched electroactive bacterial community DC5 on the performance of a pilot scale sequential two-step Horizontal Sub-surface flow Constructed WetlandMicrobial Fuel Cell (HSCW-MFC) system treating textile dye wastewater. The system consisted of CW-MFC-1 planted with Fimbristylis ferruginea and CW-MFC-2 planted with consortium of Fimbristylis ferruginea and Elymus repens plant species. Before bioaugmentation, HSCW-MFC system showed 62 ? 2% Chemical Oxygen Demand (COD) and 90 ? 1.5% American Dye Manufacturer?s Institute (ADMI) removal and 177.3 mW/m2 maximum power density (CW-MFC-1). After bioaugmentation of DC5 into the HSCW-MFC, COD and ADMI removal was enhanced to 74.10 ? 1.75% and 97.32 ? 1.90% with maximum power density of 197.94 mW/m2 (CW-MFC-1). The genera Exiguobacterium, Desulfovibrio and Macellibacteroides of DC5 were significantly enriched at the electrodes of HSCW-MFC after bioaugmentation. These results demonstrate that the performance of the CW-MFC treating textile dye wastewater can be improved by bioaugmentation of electroactive bacterial community.

Automated summary

This study demonstrated that bioaugmentation with a newly enriched electroactive bacterial community DC5 significantly improved the performance of the HSCW-MFC system treating textile dye wastewater, resulting in enhanced COD and ADMI removal rates as well as an increased maximum power density. Genera such as Exiguobacterium, Desulfovibrio, and Macellibacteroides played significant roles in the improved efficiency of the system.