Performance evaluation of sodium percarbonate‐activated peroxymonosulfate on enhancing waste activated sludge anaerobic fermentation performance

BACKGROUND To address the limited resource recovery efficiency of waste activated sludge (WAS) under single advanced oxidation processes, this study developed a combined percarbonate (SPC)‐activated peroxymonosulfate (PMS) system to enhance anaerobic fermentation performance, evaluate its applicability, and investigate its underlying mechanisms. RESULTS Results showed that the SPC/PMS system significantly improved the hydrolytic acidification performance, yielding maximum protein, polysaccharide, and short‐chain fatty acids (SCFAs) concentrations of 307.66, 174.75, and 1189.15 mg COD/L, respectively. The enhancement of hydrolytic acidification performance is closely associated with improved sludge disintegration under anaerobic conditions and increased release of soluble organic substrates, thereby promoting the subsequent fermentation process. Analysis of key enzyme activities indicated that SPC‐activated PMS significantly enhanced the activities of several key hydrolytic and acidogenic enzymes, including protease, α‐glucosidase, alkaline phosphatase, acetate kinase, and butyrate kinase, thereby accelerating the conversion of organic matter. Microbial community analysis revealed that SPC/PMS selectively enriched SCFAs‐producing bacteria, particularly Firmicutes and Actinobacteriota , while also increasing the relative abundance of sulfate‐reducing bacteria ( Desulfobacterota ). These microbial shifts were consistent with improved hydrolytic‐acidogenic performance and altered substrate utilization patterns. CONCLUSION Overall, the SPC‐activated PMS system effectively enhances WAS anaerobic fermentation performance and SCFAs production, demonstrating its potential as a promising pretreatment strategy for sludge resource recovery.