Abstract Swine wastewater is a typical high-strength animal wastewater. For treatment, it often requires combined processes (i.e., integrated units), such as multiple anaerobic reactors and advanced treatments. Microbial electrolysis cells (MECs) are a promising technology for wastewater treatment and simultaneous hydrogen harvesting. In this study, we constructed a MEC powered by an iron-air battery to treat swine wastewater and produce hydrogen efficiently. The performance of iron-air batteries with different electrolyte concentrations was compared in terms of coagulant production and power generation. The highest coagulation performance was obtained with coagulants generated using a battery with 35 g/L NaCl, which achieved 54% ± 3%, 27% ± 2%, 49% ± 1%, and 34% ± 3% removal of ammonia, chemical oxygen demand (COD), suspended solids (SS) and turbidity, respectively. Powered by the iron-air battery with 35 g/L NaCl, the hydrogen generation rate of MEC reached approximately 6 L/m3·d using raw swine wastewater and 57 L/m3·d using coagulated swine wastewater. The reduction of organics by coagulating helped improve hydrogen production. The total COD removal by the coagulation process integrated with MEC reached 98% ± 0.2%. The iron-air battery–MEC system is a promising method for simultaneous hydrogen production and wastewater treatment without any additional energy input.

中文翻译：

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用于制氢和猪废水处理的微生物电解电池-铁-空气电池组合系统

摘要 猪废水是一种典型的高浓度动物废水。对于处理，通常需要组合工艺（即集成单元），例如多个厌氧反应器和高级处理。微生物电解槽 (MEC) 是一种用于废水处理和同步氢气收集的有前途的技术。在这项研究中，我们构建了一个由铁空气电池供电的 MEC 来处理猪废水并有效地生产氢气。比较了不同电解液浓度的铁-空气电池在混凝剂生产和发电方面的性能。使用含 35 g/L NaCl 的电池产生的混凝剂获得了最高混凝性能，实现了 54% ± 3%、27% ± 2%、49% ± 1% 和 34% ± 3% 的氨、化学物质去除率需氧量（COD），分别为悬浮固体 (SS) 和浊度。由含 35 g/L NaCl 的铁空气电池供电，MEC 的产氢率在使用生猪废水时达到约 6 L/m3·d，使用凝结猪废水时达到 57 L/m3·d。通过凝结减少有机物有助于提高氢气产量。与 MEC 结合的混凝过程的总 COD 去除率达到 98%±0.2%。铁空气电池-MEC系统是一种有前景的同时制氢和废水处理的方法，无需任何额外的能量输入。与 MEC 结合的混凝过程的总 COD 去除率达到 98%±0.2%。铁空气电池-MEC系统是一种有前景的同时制氢和废水处理的方法，无需任何额外的能量输入。与 MEC 结合的混凝过程的总 COD 去除率达到 98%±0.2%。铁空气电池-MEC系统是一种有前景的同时制氢和废水处理的方法，无需任何额外的能量输入。