Anaerobic electrochemical digestion (AED) is an effective system for recovering biogas from organic wastes. However, the effects of different anode potentials on anaerobic activated sludge remain unclear. This study confirmed that biofilms exhibited the best electroactivity at −0.2 V (vs. Ag/AgCl) compared to −0.4 V and 0 V. Gas was further regulated, with the highest hydrogen content (47 ± 7 %) observed at −0.2 V. The 0 V system produced the largest amount of methane (70 ± 8 %) and exhibited the greatest presence of hydrogen-utilizing microorganisms. The gas yield at −0.4 V was the lowest, with no hydrogen detected. Excess bioelectrohydrogen at −0.2 V and 0 V caused the co-enrichment of Methanobacterium and Acetoanaerobium, establishing a thermodynamically feasible current-acetate-hydrogen electron cycle to improve electrogenesis. These results provide insights into the regulatory strategies of MEC technology during anaerobic digestion, which play a decisive role in determining the composition of biogas.

中文翻译：

---

阳极电位调节厌氧电化学消化中的气体成分和微生物组


厌氧电化学消化（AED）是从有机废物中回收沼气的有效系统。然而，不同阳极电位对厌氧活性污泥的影响仍不清楚。这项研究证实，与 -0.4 V 和 0 V 相比​​，生物膜在 -0.2 V（相对于 Ag/AgCl）表现出最佳电活性。气体得到进一步调节，在 -0.2 V 时观察到最高氢含量 (47 ± 7 %) 0 V 系统产生最大量的甲烷 (70 ± 8 %)，并表现出最多的利用氢的微生物。 -0.4V时的气体产率最低，没有检测到氢气。 -0.2 V 和 0 V 下的过量生物电氢导致甲烷杆菌和醋酸厌氧菌的共同富集，建立热力学上可行的电流-乙酸盐-氢电子循环以改善电发生。这些结果为MEC技术在厌氧消化过程中的调控策略提供了见解，这在确定沼气的成分方面发挥着决定性作用。