Gajaraj Shashikanth, Hu Zhiqiang
Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, United States.
Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, United States.
Chemosphere. 2014 Dec;117:151-7. doi: 10.1016/j.chemosphere.2014.06.013. Epub 2014 Jul 9.
Bioelectrochemical systems are emerging for wastewater treatment, yet little is known about how well they can be integrated with current wastewater treatment processes. In this bench-scale study, the microbial fuel cell (MFC) technique was incorporated into the Modified Ludzack-Ettinger (MLE) process (phase I) and later with the membrane bioreactor (MBR) process (phase II) to evaluate the performance of MFC assisted wastewater treatment systems (i.e., MLE-MFC and MBR-MFC). There was no significant difference in the effluent NH4(+)-N concentration between the systems integrating MFC and the open circuit controls. The average effluent COD concentration was significantly lower in the MLE-MFC, but it did not change much in the MBR-MFC because of the already low COD concentrations in MBR operation. The MLE-MFC and MBR-MFC systems increased the NO3(-)-N removal efficiencies by 31% (±12%) and 20% (±12%), respectively, and reduced sludge production by 11% and 6%, respectively, while generating an average voltage of 0.13 (±0.03) V in both systems. Analysis of the bacterial specific oxygen uptake rate, the sludge volume index, and ammonia-oxidizing bacterial population (dominated by Nitrosomonas through terminal restriction fragment length polymorphism analysis) indicated that there was no significant difference in sludge activity, settling property, and nitrifying community structure between the MFC assisted systems and the open circuit controls. The results suggest that the wastewater treatment systems could achieve higher effluent water quality and lower sludge production if it is integrated well with MFC techniques.
生物电化学系统正逐渐应用于废水处理，但对于它们与当前废水处理工艺的整合效果，人们了解甚少。在这项实验室规模的研究中，微生物燃料电池（MFC）技术被纳入改良的Ludzack-Ettinger（MLE）工艺（第一阶段），随后又与膜生物反应器（MBR）工艺（第二阶段）相结合，以评估MFC辅助废水处理系统（即MLE-MFC和MBR-MFC）的性能。在整合了MFC的系统与开路对照之间，出水NH4(+)-N浓度没有显著差异。MLE-MFC中的平均出水COD浓度显著更低，但由于MBR运行时COD浓度本就较低，MBR-MFC中的该浓度变化不大。MLE-MFC和MBR-MFC系统分别将NO3(-)-N去除效率提高了31%（±12%）和20%（±12%），并分别减少了11%和6%的污泥产量，同时两个系统均产生了平均为0.13（±0.03）V的电压。对细菌比氧摄取率、污泥体积指数和氨氧化细菌种群（通过末端限制性片段长度多态性分析，以亚硝化单胞菌为主）的分析表明，MFC辅助系统与开路对照之间在污泥活性、沉降性能和硝化群落结构方面没有显著差异。结果表明，如果废水处理系统能与MFC技术良好整合，就能实现更高的出水水质和更低的污泥产量。
