生物产电人工湿地系统对处理生活污水的效能

摘要

Aiming at the low purification rate of pollutants in the constructed wetland system ,a microbial fuel cell‐constructed wetland(MFC‐CW) system was developed to recycle the chemical energy in sewage by the form of electricity energy while dealing with the domestic sewage .A MFC‐CW system with canna planted was started for investigation .The treatment efficiency and electricity generation performance of the MFC‐CW system on normal pollutants in domestic sewage were studied under different hydraulic retention time (HRT ) .Results showed that with the extension of HRT reduction rate of COD and the removal efficiencies of NH+4‐N first increase and then decrease ,and that of suspend solid (SS ) increases gradually .The internal resistance and Columbic efficiency of the MFC‐CW system increase with the extension of HRT ,while the power density decreases gradually .The decrease of dissolved oxygen (DO) of cathodic chamber make cathodic potential decrease .Intermittent aeration mode in cathodic chamber can reduce the system power consumption while the ensuring the steady voltage output .%针对人工湿地系统中污染物净化速率缓慢的问题，构建生物产电人工湿地（M FC‐CW ）系统，在处理生活污水的同时将污水中的化学能以电能的形式回收。启动以美人蕉为湿地植物的M FC‐CW系统，研究不同水力停留时间（HRT ）下该系统对生活污水中常规污染物的处理效果以及产电性能。结果表明：随着水力停留时间的延长， M FC‐CW系统对污水中COD的降低率和N H＋4‐N的去除率呈现先升高后降低的趋势，悬浮物（SS ）的去除效率逐渐提高，系统的内阻逐渐增大，功率密度逐渐减小，库仑效率逐渐增加。阴极溶解氧（DO ）浓度的降低导致阴极电极的电势降低，对阴极采用间歇曝气模式可以在保证电压稳定输出的同时降低系统能耗。