Xu Lei, Zhao Yaqian, Wang Tongyue, Liu Ranbin, Gao Fei
UCD Dooge Centre for Water Resources Research, School of Civil Engineering, University College Dublin, Belfield, Dublin 4, Ireland E-mail:
Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, Dublin 2, Ireland.
Water Sci Technol. 2017 Jul;76(1-2):28-34. doi: 10.2166/wst.2017.168.
To improve the sustainability of constructed wetlands (CWs), a novel tiered wetland system integrated with a microbial fuel cell (MFC) was developed in this study. Compared to the single stage CW, chemical oxygen demand (COD) removal efficiency was improved from 83.2% to 88.7%. More significantly, this tiered system significantly enhanced total nitrogen removal efficiency (an increase from 53.1% to 75.4%). In terms of MFC integration, a gradually decreased performance in electricity production was observed during its 3 months of operation (the voltage dropped from nearly 600 mV to less than 300 mV), which resulted in a reduction of power density from around 2 W/m to less than 0.5 W/m. The deterioration in performance of the air-cathode is the main reason behind this, since the electrode potential of the cathode under open circuit reduced from 348.5 mV to 49.5 mV while the anode potential kept constant at around -400 mV. However, in spite of its electrical performance reduction, it was proved that MFC integration enhanced COD removal and the nitrification process. Further work is needed to improve the stability and feasibility of this new system.
为提高人工湿地（CWs）的可持续性，本研究开发了一种与微生物燃料电池（MFC）集成的新型分层湿地系统。与单级人工湿地相比，化学需氧量（COD）去除效率从83.2%提高到了88.7%。更显著的是，这种分层系统显著提高了总氮去除效率（从53.1%提高到75.4%）。在MFC集成方面，在其运行的3个月期间观察到发电性能逐渐下降（电压从近600 mV降至低于300 mV），这导致功率密度从约2 W/m降低到低于0.5 W/m。空气阴极性能的恶化是其背后的主要原因，因为开路条件下阴极的电极电位从348.5 mV降至49.5 mV，而阳极电位保持在约-400 mV不变。然而，尽管其电性能有所下降，但事实证明MFC集成提高了COD去除率和硝化过程。需要进一步开展工作以提高这种新系统的稳定性和可行性。
