Chuenchart Wachiranon, Sawaya Christelle, Surendra K C, Smith Adam L, Khanal Samir Kumar
Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, USA; Department of Civil, Environmental and Construction Engineering (CECE), University of Hawai'i at Mānoa, USA; Quasar Energy Group, 2705 Selby Road, Wooster, OH 44691-4096, USA.
Astani Department of Civil and Environmental Engineering, University of Southern California, USA.
Bioresour Technol. 2025 Jul;427:132398. doi: 10.1016/j.biortech.2025.132398. Epub 2025 Mar 15.
Anaerobic co-digestion (AcoD) of sewage sludge (SS) with food waste (FW) is a practical approach in urban areas due to spatio-temporal availability of these co-substrates. While micro-aeration could enhance hydrolysis and control acidification during mono-digestion, the effects of micro-aeration on AcoD remains unclear. This study explored the influence of oxidation-reduction potential (ORP)-based in-situ micro-aeration on AcoD performance of SS and FW. Although mono-digestion of FW failed due to acidification and micro-aeration of SS was unstable due to high solids content and viscosity, micro-aeration improved specific biogas and methane yields by 21.1 % and 13.1 %, respectively, at the FW:SS ratio of 60:40 ((volatile solids (VS) basis). This improvement was observed at an organic loading rate of 2.25 g VS/L·d and alkalinity below 5000 mg CaCO/L. The observed positive effect of micro-aeration was accompanied by changes in relative abundance of Aminicenantes. Functional analysis suggested that AcoD was driven by homoacetogenesis and acetoclastic methanogenesis.
由于这些共底物在时空上的可得性，污水污泥（SS）与食物垃圾（FW）的厌氧共消化（AcoD）是城市地区一种切实可行的方法。虽然微曝气可以在单消化过程中增强水解并控制酸化，但微曝气对AcoD的影响仍不清楚。本研究探讨了基于氧化还原电位（ORP）的原位微曝气对SS和FW的AcoD性能的影响。尽管由于酸化导致FW单消化失败，且由于高固体含量和粘度导致SS微曝气不稳定，但在FW:SS比例为60:40（基于挥发性固体（VS））时，微曝气分别使比沼气产量和甲烷产量提高了21.1%和13.1%。在有机负荷率为2.25 g VS/L·d且碱度低于5000 mg CaCO/L时观察到了这种改善。观察到的微曝气的积极作用伴随着氨基短杆菌属相对丰度的变化。功能分析表明，AcoD是由同型产乙酸和乙酸裂解产甲烷驱动的。
