College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
Yangtze Eco-Environment Engineering Research Center, China Three Gorges Corporation, Beijing 100038, China; Yangtze River Eco-Environmental Engineering Research Center, Shanghai Investigation, Design and Research Institute Co., LTD, Shanghai 200092, China.
J Environ Sci (China). 2025 Feb;148:321-335. doi: 10.1016/j.jes.2023.08.022. Epub 2023 Aug 28.
Sewage sludge in cities of Yangzi River Belt, China, generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system, which caused low bioenergy recovery and carbon emission benefits in conventional anaerobic digestion (CAD). Therefore, this paper is on a pilot scale, a bio-thermophilic pretreatment anaerobic digestion (BTPAD) for low organic sludge (volatile solids (VS) of 4%) was operated with a long-term continuous flow of 200 days. The VS degradation rate and CH yield of BTPAD increased by 19.93% and 53.33%, respectively, compared to those of CAD. The analysis of organic compositions in sludge revealed that BTPAD mainly improved the hydrolysis of proteins in sludge. Further analysis of microbial community proportions by high-throughput sequencing revealed that the short-term bio-thermophilic pretreatment was enriched in Clostridiales, Coprothermobacter and Gelria, was capable of hydrolyzing acidified proteins, and provided more volatile fatty acid (VFA) for the subsequent reaction. Biome combined with fluorescence quantitative polymerase chain reaction (PCR) analysis showed that the number of bacteria with high methanogenic capacity in BTPAD was much higher than that in CAD during the medium temperature digestion stage, indicating that short-term bio-thermophilic pretreatment could provide better methanogenic conditions for BTPAD. Furthermore, the greenhouse gas emission footprint analysis showed that short-term bio-thermophilic pretreatment could reduce the carbon emission of sludge anaerobic digestion system by 19.18%.
中国长江流域城市的污水污泥由于排水系统泄漏，通常表现出较低的有机含量和较高的淤泥含量，这导致传统厌氧消化（CAD）中的生物能源回收和碳排放量效益较低。因此，本文在中试规模上，对低有机污泥（挥发性固体（VS）为 4%）进行了生物高温预处理厌氧消化（BTPAD），连续运行 200 天。与 CAD 相比，BTPAD 的 VS 降解率和 CH 产率分别提高了 19.93%和 53.33%。污泥中有机成分的分析表明，BTPAD 主要改善了污泥中蛋白质的水解。通过高通量测序进一步分析微生物群落比例表明，短期生物高温预处理富集了梭菌目、梭状芽孢杆菌属和格尔里亚菌属，能够水解酸化的蛋白质，并为后续反应提供更多的挥发性脂肪酸（VFA）。生物量结合荧光定量聚合酶链反应（PCR）分析表明，BTPAD 中具有高产甲烷能力的细菌数量在中温消化阶段远高于 CAD，表明短期生物高温预处理可为 BTPAD 提供更好的产甲烷条件。此外，温室气体排放足迹分析表明，短期生物高温预处理可使污泥厌氧消化系统的碳排放量减少 19.18%。
