Anaerobic digestion (AD) is an effective and applicable technology for treating organic wastes to recover bioenergy, but it is limited by various drawbacks, such as long start-up time for establishing a stable process, the toxicity of accumulated volatile fatty acids and ammonia nitrogen to methanogens resulting in extremely low biogas productivities, and a large amount of impurities in biogas for upgrading thereafter with high cost. Microbial electrolysis cell (MEC) is a device developed for electrosynthesis from organic wastes by electroactive microorganisms, but MEC alone is not practical for production at large scales. When AD is integrated with MEC, not only can biogas production be enhanced substantially, but also upgrading of the biogas product performed in situ. In this critical review, the state-of-the-art progress in developing AD-MEC systems is commented, and fundamentals underlying methanogenesis and bioelectrochemical reactions, technological innovations with electrode materials and configurations, designs and applications of AD-MEC systems, and strategies for their enhancement, such as driving the MEC device by electricity that is generated by burning the biogas to improve their energy efficiencies, are specifically addressed. Moreover, perspectives and challenges for the scale up of AD-MEC systems are highlighted for in-depth studies in the future to further improve their performance.

中文翻译：

---

厌氧消化与微生物电解池相结合，提高沼气产量和原位升级


厌氧消化（AD）是一种有效且适用的处理有机废物以回收生物能的技术，但它受到各种缺点的限制，例如建立稳定工艺的启动时间长、积累的挥发性脂肪酸和氨氮的毒性产甲烷菌导致沼气产率极低，且沼气中含有大量杂质，后续提质成本较高。微生物电解池（MEC）是一种通过电活性微生物对有机废物进行电合成而开发的装置，但仅MEC并不适合大规模生产。当AD与MEC集成时，不仅可以大幅提高沼气产量，还可以就地进行沼气产品的升级。在这篇批判性评论中，评论了 AD-MEC 系统开发的最新进展，以及产甲烷和生物电化学反应的基础知识、电极材料和配置的技术创新、AD-MEC 系统的设计和应用以及策略针对它们的增强，例如通过燃烧沼气产生的电力来驱动 MEC 设备以提高其能源效率，都得到了专门解决。此外，还强调了 AD-MEC 系统规模化的前景和挑战，以便将来进行深入研究，以进一步提高其性能。