基于MFC的UASB厌氧消化过程生物传感器特性研究

摘要

A novel coupled system combining up flow anaerobic sludge blankets (UASB) and microbial fuel cells (MFC) was designed for online monitoring the anaerobic digestion processes of UASB. The start of the UASB-MFC system and the formation of bio-particles were studied, and the correlation between suspension COD concentration and MFC voltage were evaluated. The situation of MFC voltage feedback under imbalance system conditions was studied. The results show that this coupled reactor can achieve quick start in 23 days to produce bio-particles. There exists certain correlation between voltage signal and substrate concentration under influent concentrations of 1000~3000 mgL1, in this stage the treatment efficiency of the UASB is relatively high. The MFC voltage increases slowly under lower influent concentrations, which demonstrates the UASB reactor is under low-load operation. Mean while, high influent concentrations led to MFC voltage decrease and system be acidified, which restrains microbial activity and decreases COD removal efficiency. The operation of MFC is stable during 180 days of operation. These results suggest that the MFC signal can reflect dynamic variation of UASB and can potentially be a valuable tool for monitoring and controlling the bio-processes.%为改善升流式厌氧污泥床(UASB)工艺缺少动态信息和在线监测工具，设计了一套新型的升流式厌氧污泥床微生物燃料电池(UASB-MFC)耦合系统用以在线监测厌氧消化过程。对UASB-MFC反应器启动及生物颗粒形成进行了研究，并考察悬浮液COD浓度与MFC电压之间的关系，以及系统失衡条件下MFC电压反馈情况。结果表明，该耦合反应器23天可快速启动，形成生物颗粒。在进水浓度为1000~3000 mgL1时，电压与基质浓度存在一定的关系，此阶段UASB处理效率较高。当进水浓度较低时，MFC电压上升平缓，此阶段处于低负荷运行；当进水浓度较高时MFC电压下降，系统出现酸化，抑制微生物活性，COD去除率下降。稳定运行180天，MFC 的稳定性良好。上述结果表明MFC电信号能够反映UASB内部的动态过程，将成为一种用来监测和控制生物过程的重要工具。