Electricity generation from Taihu Lake cyanobacteria by sediment microbial fuel cells

BACKGROUND: Cyanobacteria are rich in carbohydrates and proteins as well as other nutrients. In recent years, its efficient treatment and utilization has become an important topic for debate. The feasibility of electricity generation from Taihu Lake cyanobacteria by sediment microbial fuel cell (SMFC) was investigated and its performance evaluated by comparing with glucose-fed and acetate-fed SMFCs. RESULTS: A SMFC using acidic fermentation broth of Taihu Lake cyanobacteria generated a maximum power density of 72 mW m-2 with COD removal of 76.2% and substrate degradation rate (SDR) 0.607 kgCOD m-3 d-1. A power density of 51 mW m-2 with COD removal of 72.0% and SDR of 0.573 kgCOD m-3 d-1 were obtained with an acetate-fed SMFC. The redox peaks in the voltammogram curves of the SMFC fed with acidic fermentation broth of Taihu Lake cyanobacteria suggested mediating compounds existed during its stable operation. The electron transfer was possibly carried out by cell-bound redox components or biofilm formation with electroactive bacteria on the anode surface. CONCLUSIONS: This paper describes a potential method to recover sustainable electricity from Taihu Lake cyanobacteria, and the acidic fermentation of pretreated cybanobacteria could significantly enhance the power output and COD removal. Copyright (c) 2012 Society of Chemical Industry