Improved the in-situ remediation effect of benthic microbial electrochemical system by optimizing the anode structure.

Six 60-L benthic microbial electrochemical systems (BMESs) were built for the bioremediation of river sediment. Carbon mesh anodes with honeycomb-structure supports were compared with horizontal anodes, and the system was tested using different cover depths and anode densities. The pollutant removal, electricity generation, and electrochemistry of the six BMES with different anodes was examined using the Ashi River (Harbin, China) as a case study. Total organic carbon and total nitrogen removal from sediments in BMES with Honeycomb-structure anodes were 20-30% and 20-33% higher for the other reactors. The maximum power densities of 43.2 mW m-2 was obtained in BMES. The maximum power densities in BMES with honeycomb-structure anodes were 10-40% higher than that of BMESs with horizontal anode reactors.