Abstract Most microbial desalination cells (MDCs) in previous research were constructed of three chambers fed with municipal wastewater as anolyte. In the present study, a unique design of MDC, named… Click to show full abstract
Abstract Most microbial desalination cells (MDCs) in previous research were constructed of three chambers fed with municipal wastewater as anolyte. In the present study, a unique design of MDC, named quadripartite microbial desalination cell (QMDC), was designed and fabricated to demonstrate the feasibility of a 9-chamber MDC for co-treatment of septage (septic tank sludge) and municipal wastewater. It was found that maximum power density, COD removal in anode chamber, and desalination rate at the COD concentration of 4911.6 ± 71 mg L−1 (mixing ratio of 1:10) were 8.16 W m−3, 58.4%, and 72.8% over a short-term operation; corresponding data in QMDC containing lower COD concentration (mixing ratio of 1:100) decreased to 7.2 W m−3, 49.8%, and 69.7%, respectively. In addition, longer operation of QMDCs showed a significant drop in the performance of QMDC fed with higher fraction of septage (mixing ratio of 1:10). Regarding COD removal, transferring treated anolyte solution from anode to cathode chamber improved total COD removal by 91.1%. It was found that although QMDC performance in electricity production and salt removal was relatively better in mixing ratio of 1:10, the use of higher mixing ratio (1:100) is firmly suggested because of higher stability of the process under long-term operation.
               
Click one of the above tabs to view related content.