Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China.
Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China.
Environ Pollut. 2021 Mar 1;272:116030. doi: 10.1016/j.envpol.2020.116030. Epub 2020 Nov 20.
The anaerobic digestion of wastewater rich in volatile fatty acids (VFAs) provides a sustainable approach for methane production whilst reducing environmental pollution. However, the anaerobic digestion of VFAs may not be stable during long-term operation under a short hydraulic retention time. In this study, conductive carbon cloth was supplemented to investigate the impacts on the anaerobic digestion of VFAs in wastewater sourced from dark fermentation. The results demonstrated that the failure of anaerobic digestion could be avoided when carbon cloth was supplemented. In the stable stage, the methane production rate with carbon cloth supplementation was improved by 200-260%, and the chemical oxygen demand (COD) removal efficiency was significantly enhanced compared with that in the control without carbon cloth. The relative abundance of potential exoelectrogens on the carbon cloth was increased by up to 8-fold compared with that in the suspension. Electrotrophic methanogens on the carbon cloth were enriched by 4.2-17.2% compared with those in the suspension. The genera Ercella and Petrimonas along with the methanogenic archaea Methanosaeta and Methanosarcina on the carbon cloth may facilitate direct interspecies electron transfer, thereby enhancing methane production.
富含挥发性脂肪酸（VFAs）的废水的厌氧消化为甲烷生产提供了一种可持续的方法，同时减少了环境污染。然而，在水力停留时间短的情况下，VFAs 的厌氧消化在长期运行中可能不稳定。在这项研究中，补充了导电碳布，以研究其对源自黑暗发酵的废水的 VFAs 厌氧消化的影响。结果表明，补充碳布可以避免厌氧消化的失败。在稳定阶段，补充碳布后甲烷的产率提高了 200-260%，与无碳布的对照相比，化学需氧量（COD）去除效率显著提高。碳布上的潜在外电子供体的相对丰度比悬浮液中的增加了 8 倍。与悬浮液相比，碳布上的电营养产甲烷菌富集了 4.2-17.2%。碳布上的 Ercella 和 Petrimonas 属以及甲烷生成古菌 Methanosaeta 和 Methanosarcina 可能有助于直接种间电子转移，从而提高甲烷产量。
