Wen Han-Quan, Chen Guan-Lin, Li Yu-Sheng, Tian Tian, Pan Yuan, Yu Han-Qing
CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Technology, University of Science and Technology of China, Hefei 230026, China.
Institute of Advanced Technology, University of Science and Technology of China, Hefei 230000, China.
Water Res X. 2024 Nov 23;26:100286. doi: 10.1016/j.wroa.2024.100286. eCollection 2025 Jan 1.
Iron (hydro)oxides are commonly used to enhance anaerobic digestion due to their cost-effectiveness and versatility. However, the influence of crystalline structure on digestion performance is often overlooked despite their unique characteristics. In this study, we investigated how different crystalline forms of FeOOH affect substrate utilization, sludge activity, and the microbiomes in up-flow anaerobic sludge blanket (UASB) reactors. The crystalline structure of FeOOH impacted reactor performance, with γ-FeOOH, β-FeOOH, and α-FeOOH showing decreasing effectiveness, as reflected in chemical oxygen demand (COD) removal efficiencies of 99.0 %, 98.3 % and 97.1 %, respectively. FeOOH crystals influenced the secretion of extracellular polymeric substances (EPS) and sludge activity by releasing Fe ions at varying rates, leading to Fe accumulation in EPS in the order of β-FeOOH > γ-FeOOH > α-FeOOH. Additionally, γ-FeOOH supported the most stable microbial community structure, as indicated by the highest Alpha diversity index. This stability was associated with increased levels of and , along with the highest coenzyme F activity, which was approximately twice as high as in other groups. These findings underscore the crucial role of the crystalline structure of iron oxides in enhancing anaerobic digestion, emphasizing that biocompatibility should be a priority when optimizing digestion performance.
氢氧化铁由于其成本效益和多功能性而常用于强化厌氧消化。然而，尽管它们具有独特的特性，但晶体结构对消化性能的影响却常常被忽视。在本研究中，我们调查了不同晶型的FeOOH如何影响上流式厌氧污泥床（UASB）反应器中的底物利用、污泥活性和微生物群落。FeOOH的晶体结构影响了反应器性能，γ-FeOOH、β-FeOOH和α-FeOOH的有效性依次降低，化学需氧量（COD）去除效率分别为99.0%、98.3%和97.1%。FeOOH晶体通过以不同速率释放铁离子影响细胞外聚合物（EPS）的分泌和污泥活性，导致EPS中铁的积累顺序为β-FeOOH > γ-FeOOH > α-FeOOH。此外，γ-FeOOH支持最稳定的微生物群落结构，这由最高的Alpha多样性指数表明。这种稳定性与 和 水平的增加以及最高的辅酶F活性相关，辅酶F活性大约是其他组的两倍。这些发现强调了铁氧化物晶体结构在强化厌氧消化中的关键作用，强调在优化消化性能时生物相容性应是优先考虑的因素。
