阴极液及底物浓度对AFB-MFC同步废水处理及产电性能影响

为了提高厌氧流化床微生物燃料电池（AFB-MFC）的性能，并为双室MFC寻找价廉、易得、无污染的阴极液，在曝气量16～24 L/h、温度（35±2）℃、回流量10.2 L/h、阴极底边距阴极室内底部17.3 cm、外电阻250 Ω、水力停留时间（HRT）14.0～14.9 h以及进水pH 7.81～8.37下，研究了阴极液及底物浓度对系统产电及废水处理性能的影响。结果表明，使用缓冲溶液、阳极室出水和自来水作阴极液时，自来水的产电性能最佳，阴极液种类不影响系统有机基质的去除。以自来水为阴极液时，阴极液pH及电导率随运行时间增加而增加，COD去除率为80.11%～89.29%，输出电压及功率密度开始随运行时间增加而增加，之后稳定在440～452 mV和48.40～51.08 mW/m²之间。增加底物浓度对COD去除率影响不大，而输出电压及功率密度随底物浓度增加而下降；底物COD浓度由3 307.09 mg/L增至9 520 mg/L时，COD去除率在85.77%～94.44%之间，输出电压及功率密度则分别由449 mV和50.40 mW/m²下降至406 mV和41.21 mW/m²。自来水作阴极液可避免二次污染及阴极液对阳极室微生物的影响，并得到高的产电能力。

Effects of catholyte and substrate concentration on simultaneous wastewater treatment and electricity production for AFB-MFC

In order to improve the performance of anaerobic fluidized bed microbial fuel cell(AFB-MFC) and look for cheap,easy to get and no pollution catholyte for two chambers’ MFC,the effects of catholyte and substrate concentration on electricity generation and wastewater treatment were studied.The AFB-MFC system was operated under the conditions of aeration rate of 16~24 L/h,35±2℃,distance between the bottom of cathode and the inner bottom of cathode chamber of 17.3 cm,external resistance of 250 Ω,hydraulic retention time(HRT) of 14.0~14.9 h and influent pH of 7.81~8.37.The results showed that the best electricity generation was resulted from using tap water as catholyte among buffer solution,anode effluent and tap water.The removal efficiency of substrate was not affected by catholyte.The pH and conductivity of catholyte increased with operation time when tap water was used as catholyte.And COD removal efficiency was 80.11%~89.29%.Voltage and power density increased with time at the beginning,then they stabilized at 440~452 mV and 48.40~51.08 mW/m2.The COD removal efficiency was not affected by substrate concentration,but voltage and power density decreased with the increase of substrate concentration.When the COD concentration of substrate increased from 3 307.09 mg/L to 9 520 mg/L,the COD removal efficiency was 85.77%~94.44% and the voltage and power density decreased from 449 mV and 50.40 mW/m2 to 406 mV and 41.21 mW/m2.Secondary pollution and effects of catholyte to anodic microorganisms can be avoided and high power output was achieved when tap water was used as catholyte.