Research
| Title： | Study on pyrrhotite activating peroxydisulfate to enhance anaerobic fermentation of waste activated sludge for short-chain fatty acids production |
|---|---|
| First author： | Yu, Zhou; Wang, Qiang; An, Heng; Ruan, Tianqi; Lu, Xinyi; Wu, Zhenbin; Zhou, Qiaohong; Xiao, Enrong |
| Journal： | CHEMICAL ENGINEERING JOURNAL |
| Years： | 2025 |
| DOI： | 10.1016/j.cej.2025.165340 |
| Abstract： | As an effective resource recovery technology for waste activated sludge (WAS), anaerobic fermentation (AF) is often constrained by the hydrolysis step. This study proposes a novel pretreatment strategy using pyrrhotite (Po)-activated peroxydisulfate (PDS) to address the low hydrolysis efficiency in AF process of WAS. Batch experiments revealed optimal performance at 0.3 g PDS + 1.5 g Po/g VSS, achieving a short-chain fatty acid (SCFAs) yield of 1225.8 +/- 69.0 mg COD/L (75.8% acetic acid) on day 12, representing 4.0- and 1.3-fold enhancements over PDS-only and low-Po (0.1 g/g VSS) systems, respectively. Semi-continuous reactor tests with 0.1 g Po +0.3 g PDS (Po-PDS) demonstrated 78.8% hydrolysis efficiency improvement via SO4- driven extracellular polymeric substance disruption, verified by the 2.85, 1.38 and 2 times relative content of lactate dehydrogenase, alpha-glucosidase and protease compared to PDS controls. Microbial analysis identified Caloramatoraceae (30.3%) and Romboutsia 21.1%) as dominant acidogenic genera, directly correlating with acetic acid accumulation. Recovered Po exhibited retained magnetism (>70% recovery) and structural stability through sulfur-mediated Fe3+/Fe2+ cycling, enabling sustained PDS activation. This work establishes Po-PDS as an efficient and recyclable pretreatment system for sludge resource recovery. Future research should focus on elucidating the Fe3+/Fe2+ redox cycling mechanism governing sustained SO4- generation in the Po-PDS system, coupled with comprehensive parameter optimization to accelerate its engineering application. |
