Electricity generation from molasses wastewater by an anaerobic baffled stacking microbial fuel cell

Abstract

Abstract BACKGROUND: The conventional treatment of molasses wastewater has many disadvantages including intensive energy requirements, excessive chemicals consumption and large quantities of waste generation. The microbial fuel cell (MFC) is a promising technology for power generation along with wastewater treatment. However, low power output and high construction costs limit the scale‐up and field implementation of MFCs. In this study, a novel anaerobic baffled stacking microbial fuel cell (ABSMFC) composed of four units was constructed and used to treat molasses wastewater. RESULTS: The ABSMFC was operated at three different organic loading rates (OLRs) and the highest average power density of 115.5 ± 2.7 mW m −2 was achieved for the four units at an OLR of 3.20 kg COD m −3 d −1 . Accordingly, 50–70% of total COD removal efficiency was accomplished. Power generation was further improved in terms of voltage or current by connecting units in series or parallel. The low voltage loss (8.1%) during series connection resulted from low parasitic current of adjacent units. CONCLUSION: The ABSMFC is effective for molasses wastewater treatment. It can promote current or voltage output and minimize energy loss during series connection. This is a promising scalable architecture and can be combined with other existing wastewater treatment technologies. Copyright © 2010 Society of Chemical Industry