Abstract: Microbial fuel cell(MFC) coupled with struvite crystallization can simultaneously recover the abundant nutrients such as nitrogen and phosphorus from waste activated sludge(WAS) in municipal sewage treatment plants, thereby presenting promising application prospects in the WAS resource utilization. In this study, the effects of different cathodic electron acceptors on the electricity production performance of MFC were investigated. Through Box-Behnken based response surface methodology, the maximum power output of MFC under different initial pH values, temperatures and sludge inoculation ratios in the anolyte was simulated and predicted, and the optimal anode operating conditions were also obtained. Meanwhile, the recovery efficiency of nitrogen and phosphorus from the sludge supernatant after MFC operation by struvite crystallization and the properties of crystallization products were discussed. The results show that when potassium ferricyanide( $ K_{3}[Fe(CN)_{6}] $) is used as cathodic electron acceptor, the output voltage and maximum power density of MFC are 0.64 V and 2.66 W/m $ ^{3} $, respectively, which are 3.0 and 2.5 times higher than that of MFC with oxygen as cathodic electron acceptor. The optimal anode operating conditions are 55 °C, initial pH value of 9.8, and sludge inoculation ratio of 0.37, under which MFC achieves a maximum power density of 6.82 W/m $ ^{3} $. After MFC operation, the removal rate of phosphorus from the sludge supernatant by struvite crystal-
Keywords: waste activated sludge(WAS); microbial fuel cell(MFC); cathodic electron acceptor; Box-Behnken model; struvite crystallization
合肥工业大学学报自科版